Patent Publication Number: US-2023147179-A1

Title: Wireless power transmission device

Description:
TECHNICAL FIELD 
     The present disclosure relates to a wireless power transmission device to transmit electric power wirelessly to a movable body by radio waves. 
     BACKGROUND ART 
     A system in which a direction of a transmitted microwave beam for the power transmission is controlled by controlling the microwaves radiated from a plurality of element antennas is developed (see NPL 1). This system is developed for the purpose of the remote power transmission using the radio waves in a frequency band such as a microwave. In this system, an amplitude mono-pulse method and a rotating element electric field vector (REV) method (REV method) are adopted for beam control. High-efficient wireless power transmission using microwaves is provided by adopting the amplitude mono-pulse method and the REV method. A pilot signal guiding a transmission direction of a power transmission microwave is transmitted from the power-receiving side, each power transmission panel detects an arrival direction of the pilot signal using the amplitude mono-pulse method, and microwave is radiated in the arrival direction of the pilot signal. An optical path length difference corresponding to a level difference between the power transmission panels is detected and corrected by the REV method. A monitor antenna is attached to an XY scanner movable in two dimensions, thereby measuring a beam direction or a radiation pattern of the microwave with which the power is transmitted. 
     A wireless power transmission system is proposed which transmits power wirelessly to a movable body such as a drone using a phased array antenna as a power transmission antenna. In a wireless power transmission device using a phased array antenna, the phase of a radio wave radiated by each element antenna included in the power transmission antenna is controlled to form a power transmission beam in the direction in which a power reception device included in the movable body is present. In a state in which the phase references of element antennas are not equalized, a beam is unable to be formed in the transmission direction. In order to equalize the phase references of element antennas included in the phased array antenna before power is transmitted to a movable body, measurement is performed by the REV method based on the electric power received by a movable body hovering in the air (see PTL 1). The method of equalizing the phase references of element antennas by the REV method is a well-known technique (see PTL 2). 
     CITATION LIST 
     Patent Literature 
     
         
         PTL 1: Japanese Patent Laying-Open No. 2019-75984 
         PTL 2: Japanese Examined Patent Application Publication No. H1-37882 
       
    
     Non Patent Literature 
     
         
         NPL 1: Katsumi Makino et al. “Development and Demonstration of the High-Precision Beam Steering Controller for Microwave Power Transmission, which takes account of applying to SSPS (Space Solar Power Systems)”, the Institute of Electronics, Information and Communication Engineers (IEICE) Technical Report, SANE 2015-22, pp. 37-42, June 2015. 
       
    
     SUMMARY OF INVENTION 
     Technical Problem 
     In the wireless power transmission device in which radio waves are radiated from a power transmission antenna being a phased array antenna to transmit electric power wirelessly, the phase of a radio wave radiated by each element antenna deviates due to various reasons, leading to deterioration in power transmission efficiency. When the power transmission efficiency is deteriorated, the REV method is executed to equalize the phase references of radio waves radiated by element antennas. In the REV method, the phase references of radio waves radiated by element antennas are equalized based on the received power strength obtained by measuring radio waves received by a measurement antenna having a fixed position. When a moving movable body is equipped with a measurement antenna, the measurement antenna measures the received power strength, including deterioration in received power strength due to movement of the movable body. This deteriorates the accuracy of executing the REV method. Despite executing the REV method, the phase references of radio waves radiated by the element antennas sometimes fail to be equalized. 
     The present disclosure is made to solve the problem described above and an object of the present disclosure is to obtain a wireless power transmission device that can execute the REV method more accurately than by the conventional method when the REV method is executed for a moving movable body. 
     Solution to Problem 
     A wireless power transmission device according to the present disclosure includes: a power transmission antenna to transmit electric power by radiating a radio wave and being capable of changing a radiation direction being a direction in which the radio wave is radiated, the power transmission antenna being a phased array antenna including a plurality of element antennas to radiate the radio wave and a plurality of element modules each provided for a predetermined number of the element antennas, each of the plurality of element modules including a phase shifter to change a phase of a transmission signal radiated as the radio wave and an amplifier to amplify the transmission signal, the power transmission antenna; a transmission signal generator to generate the transmission signal radiated from the power transmission antenna as the radio wave; a presence direction determiner to determine a presence direction being a direction in which a movable body is present, the movable body being equipped with a power reception device to receive the radio wave, a measurement antenna to receive the radio wave, a radio wave measurer to measure received radio wave data including an electric field strength being an amplitude of the radio wave received by the measurement antenna, and a movable body communication device; a radiation direction changer to direct the radiation direction of the power transmission antenna to the presence direction by controlling a phase shift amount being an amount by which the phase shifter changes the phase of the transmission signal; an REV method phase controller to change the phase of the transmission signal by the phase shift amount obtained by adding an operation phase shift amount being the phase shift amount defined by a phase operating pattern and a direction change phase shift amount being the phase shift amount changed by the radiation direction changer, for an operating phase shifter being part of the phase shifters, based on an REV method scenario, the operation phase shift amount being the phase shift amount defined by a phase operating pattern, the phase operating pattern being defined by the REV method scenario and describing operation of changing the phase shift amount of the operating phase shifter, the operation being repeated while changing the operating phase shifter, and being performed in a state in which at least some of the element antennas radiate the radio wave; a phase reference adjuster to equalize phase references of the transmission signals outputted by the element modules, based on element electric field phases, each of the element electric field phases being a phase of an element electric field vector detected by the measurement antenna receiving the radio wave radiated by the element antenna supplied with the transmission signal outputted by one element module, the element electric field phase being calculated based on electric field change data generated based on REV method run-time radio wave data being the received radio wave data received by the movable body, in a state in which the REV method phase controller changes the phase shift amount of the operating phase shifter based on the REV method scenario; and a power transmitting-side communication device to communicate with the movable body communication device. 
     A wireless power transmission device includes: a power transmission antenna to transmit electric power by radiating a radio wave and being capable of changing a radiation target position being a range of position in three-dimensional space set to be a target for radiating the radio wave, the power transmission antenna being a phased array antenna including a plurality of element antennas to radiate the radio wave and a plurality of element modules each provided for a predetermined number of the element antennas, each of the plurality of element modules including a phase shifter to change a phase of a transmission signal radiated as the radio wave and an amplifier to amplify the transmission signal; a transmission signal generator to generate the transmission signal radiated from the power transmission antenna as the radio wave; a presence direction determiner to determine a presence direction being a direction in which a movable body is present, the movable body being equipped with a power reception device to receive the radio wave, a measurement antenna to receive the radio wave, a radio wave measurer to measure received radio wave data including an electric field strength being an amplitude of the radio wave received by the measurement antenna, and a movable body communication device; a movable body distance measurer to measure a movable body distance being a distance from the power transmission antenna to the movable body; a radiation target position determiner to determine the radiation target position as a relative position to a power transmission antenna position being a position of the power transmission antenna, and including a movable body position being a position in three-dimensional space determined by the presence direction and the movable body distance; a radiation target position changer to radiate the radio waves such that phases are matched at the radiation target position by controlling phase shift amounts, each of the phase shift amounts being an amount by which the phase shifter changes the phase of the transmission signal; an REV method phase controller to change the phase of the transmission signal by the phase shift amount obtained by adding an operation phase shift amount and a target position change phase shift amount being the phase shift amount changed by the radiation target position changer, for an operating phase shifter being part of the phase shifters, based on an REV method scenario, the operation phase shift amount being the phase shift amount defined by a phase operating pattern, the phase operating pattern being defined by the REV method scenario and describing operation of changing the phase shift amount of the operating phase shifter, the operation being repeated while changing the operating phase shifter, and being performed in a state in which at least some of the element antennas radiate the radio wave; a phase reference adjuster to equalize phase references of the transmission signals outputted by the element modules, based on element electric field phases, each of the element electric phases being a phase of an element electric field vector detected by the measurement antenna receiving the radio wave radiated by the element antenna supplied with the transmission signal outputted by one element module, the element electric field phase being calculated based on electric field change data generated based on REV method run-time radio wave data being the received radio wave data received by the movable body, in a state in which the REV method phase controller changes the operation phase shift amount of the operating phase shifter based on the REV method scenario; and a power transmitting-side communication device to communicate with the movable body communication device. 
     Advantageous Effects of Invention 
     The wireless power transmission device according to the present disclosure can execute the REV method more accurately than by the conventional method when the REV method is executed for a moving movable body. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a first embodiment. 
         FIG.  2    is a diagram illustrating an overall configuration of the wireless power transmission system for a movable body using the wireless power transmission device according to the first embodiment. 
         FIG.  3    is a diagram for explaining the operation in which a power transmission beam does not track a movable body when the REV method is executed for a moving movable body. 
         FIG.  4    is a diagram for explaining the operation in which a power transmission beam tracks a movable body when the REV method is executed for a moving movable body. 
         FIG.  5    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the first embodiment. 
         FIG.  6    is a graph illustrating change of an amplitude attenuation ratio γ to change of a deviation angle δ in a phased array antenna included in the wireless power transmission device according to the first embodiment. 
         FIG.  7    is a diagram illustrating variables representing the positional relation between the movable body and the wireless power transmission device. 
         FIG.  8    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the first embodiment. 
         FIG.  9    is a flowchart illustrating the procedure of calculating an element electric field vector of a radio wave radiated by each element antenna by the REV method in the wireless power transmission device according to the first embodiment. 
         FIG.  10    is a diagram illustrating the loci of an electric field vector during execution of the REV method obtained in the wireless power transmission device according to the first embodiment in an operation example. 
         FIG.  11    is a diagram illustrating temporal change of the amplitude and phase of the electric field vector during execution of the REV method obtained in the wireless power transmission device according to the first embodiment in the operation example. 
         FIG.  12    is a diagram illustrating the loci of the electric field vector during execution of the REV method obtained when the movable body is not tracked during execution of the REV method as a comparative example. 
         FIG.  13    is a diagram illustrating temporal change of the amplitude and phase of the electric field vector during execution of the REV method obtained in the comparative example in the operation example. 
         FIG.  14    is a diagram comparing temporal change of the amplitude of the electric field vector during execution of the REV method obtained in the wireless power transmission device according to the first embodiment and the comparative example in the operation example. 
         FIG.  15    is a diagram illustrating a phase offset value and a phase error remaining after correction obtained in the wireless power transmission device according to the first embodiment and the comparative example, in the operation example. 
         FIG.  16    is a diagram comparing the absolute values of the amplitude of the electric field vector after correction in the wireless power transmission device according to the first embodiment and the comparative example in the operation example. 
         FIG.  17    is a diagram illustrating the pattern of phase errors used to analyze the influence of the pattern of phase errors in the wireless power transmission device according to the first embodiment and the comparative example. 
         FIG.  18    is a diagram illustrating changes of the amplitude of the electric field vector and the power value after correction to change of the moving speed of the movable body in the wireless power transmission device according to the first embodiment and the comparative example, comparing for three patterns of phase errors. 
         FIG.  19    is a diagram illustrating the patterns of phase errors used to analyze the influence of the magnitude of phase error in the wireless power transmission device according to the first embodiment and the comparative example. 
         FIG.  20    is a diagram illustrating changes of the amplitude of the electric field vector and the power value after correction to change of the moving speed of the movable body in the wireless power transmission device according to the first embodiment and the comparative example, comparing for the magnitudes of phase error. 
         FIG.  21    is a diagram illustrating changes of the amplitude of the electric field vector and the power value after correction to change of the moving speed of the movable body in the wireless power transmission device according to the first embodiment and the comparative example, comparing for the directions in which the movable body is present at the start of the REV method. 
         FIG.  22    is a diagram illustrating changes of the amplitude of the electric field vector and the power value after correction to change of the moving speed of the movable body in the wireless power transmission device according to the first embodiment and the comparative example, comparing for the angle differences between the direction in which the movable body is present at the start of the REV method and the moving direction of the movable body. 
         FIG.  23    is a diagram illustrating an overall configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a second embodiment. 
         FIG.  24    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the second embodiment. 
         FIG.  25    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the second embodiment. 
         FIG.  26    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a third embodiment. 
         FIG.  27    is a diagram illustrating an overall configuration of the wireless power transmission system for a movable body using a wireless power transmission device according to the third embodiment. 
         FIG.  28    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the third embodiment. 
         FIG.  29    is a graph illustrating change of an amplitude attenuation ratio γ to change of a deviation angle δ in the phased array antenna included in the wireless power transmission device according to the third embodiment. 
         FIG.  30    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the third embodiment. 
         FIG.  31    is a flowchart illustrating a procedure for restoring a power transmission direction to a proper angle range in the power transmission procedure to a movable body by the wireless power transmission device according to the third embodiment. 
         FIG.  32    is a diagram illustrating an overall configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a fourth embodiment. 
         FIG.  33    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the fourth embodiment. 
         FIG.  34    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the fourth embodiment. 
         FIG.  35    is a flowchart illustrating the procedure of calculating an element electric field vector of a radio wave radiated by each element antenna by the REV method in the wireless power transmission device according to the fourth embodiment. 
         FIG.  36    is a diagram illustrating an overall configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a fifth embodiment. 
         FIG.  37    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the fifth embodiment. 
         FIG.  38    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a sixth embodiment. 
         FIG.  39    is a diagram illustrating an overall configuration of the wireless power transmission system for a movable body using a wireless power transmission device according to the sixth embodiment. 
         FIG.  40    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the sixth embodiment. 
         FIG.  41    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the sixth embodiment. 
         FIG.  42    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a seventh embodiment. 
         FIG.  43    is a diagram illustrating an overall configuration of the wireless power transmission system for a movable body using a wireless power transmission device according to the seventh embodiment. 
         FIG.  44    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the seventh embodiment. 
         FIG.  45    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the seventh embodiment. 
         FIG.  46    is a block diagram illustrating a functional configuration of a wireless power transmission device and a movable body according to an eighth embodiment. 
         FIG.  47    is a flowchart illustrating a procedure of calculating an element electric field vector of a radio wave radiated by each element antenna by the REV method in the wireless power transmission device according to the eighth embodiment. 
         FIG.  48    is a block diagram illustrating a functional configuration of a wireless power transmission device and a movable body according to a ninth embodiment. 
         FIG.  49    is a flowchart illustrating a procedure of calculating an element electric field vector of a radio wave radiated by each element antenna by the REV method in the wireless power transmission device according to the ninth embodiment. 
         FIG.  50    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a tenth embodiment. 
         FIG.  51    is a diagram illustrating an overall configuration of the wireless power transmission system for a movable body using a wireless power transmission device according to the tenth embodiment. 
         FIG.  52    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the tenth embodiment. 
         FIG.  53    is a diagram illustrating an example of the state in which there is a difference between distance Gp from element antenna  8   p  to radiation target position P T  and distance G from power transmission device position P S  to radiation target position P T  in the wireless power transmission device and the movable body according to the tenth embodiment. 
         FIG.  54    is a graph illustrating change of an amplitude attenuation ratio γ to change of a deviation angle δ in the phased array antenna (L=1800 mm) of the wireless power transmission device according to the tenth embodiment. 
         FIG.  55    is a graph illustrating change of an amplitude attenuation ratio γ to change of a deviation distance G in the phased array antenna (L=1800 mm) of the wireless power transmission device according to the tenth embodiment. 
         FIG.  56    is a graph illustrating change of an amplitude attenuation ratio γ to change of a deviation angle δ in the phased array antenna (L=600 mm) of the wireless power transmission device according to the tenth embodiment. 
         FIG.  57    is a graph illustrating change of an amplitude attenuation ratio γ to change of a deviation distance G in the phased array antenna (L=600 mm) of the wireless power transmission device according to the tenth embodiment. 
         FIG.  58    is a diagram illustrating an example in which the wireless power transmission device in the tenth embodiment sets a radiation target position in accordance with the position of the moving movable body. 
         FIG.  59    is a diagram illustrating another example in which the wireless power transmission device in the tenth embodiment sets a radiation target position in accordance with the position of the moving movable body. 
         FIG.  60    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the tenth embodiment. 
         FIG.  61    is a flowchart illustrating the procedure of calculating an element electric field vector of a radio wave radiated by each element antenna by the REV method in the wireless power transmission device according to the tenth embodiment. 
         FIG.  62    is a diagram illustrating a phase offset value and a phase error remaining after correction obtained in the wireless power transmission device according to the tenth embodiment and comparative examples, in an operation example in which L=1800 mm is satisfied. 
         FIG.  63    is a diagram comparing the absolute values of the amplitude of the electric field vector after correction in the wireless power transmission device according to the tenth embodiment and the comparative example, in the operation example in which L=1800 mm is satisfied. 
         FIG.  64    is a diagram illustrating a phase offset value and a phase error remaining after correction obtained in the wireless power transmission device according to the tenth embodiment and comparative examples, in an operation example in which L=600 mm is satisfied. 
         FIG.  65    is a diagram comparing the absolute values of the amplitude of the electric field vector after correction in the wireless power transmission device according to the tenth embodiment and the comparative example in the operation example in which L=600 mm is satisfied. 
         FIG.  66    is a diagram illustrating the absolute values of the amplitude of the electric field vector after correction to change in element antenna distance L in the wireless power transmission device according to the tenth embodiment and the comparative example in the operation example, for several power transmission directions ψ 0 . 
         FIG.  67    is a diagram illustrating the absolute values of the amplitude of the electric field vector after correction to change in element antenna distance L in the wireless power transmission device according to the tenth embodiment and the comparative example in the operation example, for several moving speeds v 0  of the movable body. 
         FIG.  68    is a diagram illustrating the absolute values of the amplitude of the electric field vector after correction to change in element antenna distance L in the wireless power transmission device according to the tenth embodiment and the comparative example in the operation example, for several moving speeds v 0  of the movable body. 
         FIG.  69    is a diagram illustrating the absolute values of the amplitude of the electric field vector after correction to change in element antenna distance L in the wireless power transmission device according to the tenth embodiment and the comparative example in the operation example, for several moving directions ξ 0  of the movable body. 
         FIG.  70    is a diagram illustrating the absolute values of the amplitude of the electric field vector after correction to change in element antenna distance L in the wireless power transmission device according to the tenth embodiment and the comparative example in the operation example, for several moving directions ξ 0  of the movable body. 
         FIG.  71    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to an eleventh embodiment. 
         FIG.  72    is a diagram illustrating an overall configuration of the wireless power transmission system for a movable body using a wireless power transmission device according to the eleventh embodiment. 
         FIG.  73    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the eleventh embodiment. 
         FIG.  74    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the eleventh embodiment. 
         FIG.  75    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a twelfth embodiment. 
         FIG.  76    is a diagram illustrating an overall configuration of the wireless power transmission system for a movable body using a wireless power transmission device according to the twelfth embodiment. 
         FIG.  77    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the twelfth embodiment. 
         FIG.  78    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the twelfth embodiment. 
         FIG.  79    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a thirteenth embodiment. 
         FIG.  80    is a diagram illustrating an overall configuration of the wireless power transmission system for a movable body using a wireless power transmission device according to the thirteenth embodiment. 
         FIG.  81    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the thirteenth embodiment. 
         FIG.  82    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the thirteenth embodiment. 
         FIG.  83    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a fourteenth embodiment. 
         FIG.  84    is a diagram illustrating an overall configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to the fourteenth embodiment. 
         FIG.  85    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the fourteenth embodiment. 
         FIG.  86    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the fourteenth embodiment. 
         FIG.  87    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a fifteenth embodiment. 
         FIG.  88    is a diagram illustrating an overall configuration of the wireless power transmission system for a movable body using a wireless power transmission device according to the fifteenth embodiment. 
         FIG.  89    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the fifteenth embodiment. 
         FIG.  90    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the fifteenth embodiment. 
         FIG.  91    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a sixteenth embodiment. 
         FIG.  92    is a diagram illustrating an overall configuration of the wireless power transmission system for a movable body using a wireless power transmission device according to the sixteenth embodiment. 
         FIG.  93    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the sixteenth embodiment. 
         FIG.  94    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the sixteenth embodiment. 
         FIG.  95    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a seventeenth embodiment. 
         FIG.  96    is a diagram illustrating an overall configuration of the wireless power transmission system for a movable body using a wireless power transmission device according to the seventeenth embodiment. 
         FIG.  97    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the seventeenth embodiment. 
         FIG.  98    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the seventeenth embodiment. 
         FIG.  99    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to an eighteenth embodiment. 
         FIG.  100    is a diagram illustrating an overall configuration of the wireless power transmission system for a movable body using a wireless power transmission device according to the eighteenth embodiment. 
         FIG.  101    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the eighteenth embodiment. 
         FIG.  102    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the eighteenth embodiment. 
         FIG.  103    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a sixteenth embodiment. 
         FIG.  104    is a diagram illustrating an overall configuration of the wireless power transmission system for a movable body using a wireless power transmission device according to the nineteenth embodiment. 
         FIG.  105    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the nineteenth embodiment. 
         FIG.  106    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the nineteenth embodiment. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     First Embodiment 
       FIG.  1    is a schematic diagram illustrating a configuration of a wireless power transmission system to a movable body using a wireless power transmission device according to the present disclosure. A wireless power transmission device  1  supplies (transmits) electric power wirelessly to a movable body  60  (for example, drones, other unmanned movable bodies moving in the air, etc.) by a power transmission radio wave  2  such as microwave. Wireless power transmission device  1  includes a power transmission antenna  50  to radiate power transmission radio wave  2  and a control device  10 . Power transmission antenna  50  is a phased array antenna. Control device  10  controls power transmission antenna  50 . Movable body  60  has a power reception device  3  on its lower surface. Power reception device  3  receives power transmission radio wave  2  and converts the received power transmission radio wave  2  into electric power. The electric power transmitted by power transmission radio wave  2  is consumed by movable body  60 . Movable body  60  has a pilot transmitter  5  to transmit a pilot signal  4 . Pilot signal  5  is transmitted to notify wireless power transmission device  1  of the direction in which movable body  60  (strictly speaking, power reception device  3 ) is present. Wireless power transmission device  1  includes a pilot antenna  6  to receive pilot signal  5  and an arrival direction detecting device  7  (depicted in  FIG.  2   ) to determine the arrival direction in which pilot signal  4  arrives. Wireless power transmission device  1  radiates power transmission radio wave  2  in the direction toward the arrival direction. In order to perform communication necessary for executing the REV method, movable body  60  includes a movable body communication device  20 , and wireless power transmission device  1  includes a communication device  30 . A pilot antenna  6  is installed, for example, at the center of an opening area of power transmission antenna  50 . The arrival direction is also the presence direction that is the direction in which movable body  60  is present viewed from wireless power transmission device  1 . Arrival direction detecting device  7  is a presence direction determiner that detects the presence direction. Movable body communication device  20  and communication device  30  communicate by radio waves. Radio waves used for communication are called communication radio waves. 
     Referring to  FIG.  2   , a configuration of wireless power transmission device  1  and movable body  60  is described.  FIG.  2    is a diagram illustrating a configuration of a wireless power transmission system to a movable body using the wireless power transmission device according to a first embodiment. 
     Wireless power transmission device  1  radiates power transmission radio wave  2  toward movable body  60  by power transmission antenna  50 . Power transmission antenna  50  that is a phased array antenna includes a plurality of element antennas  8 , element modules  9  provided for corresponding element antennas  8 , a transmission signal generator  11 , and a distribution circuit  12 . Each of element antennas  8  radiate an element radio wave  2 E (not illustrated) having phase and amplitude adjusted. Element antennas  8  are arranged in a two-dimensional grid pattern at predetermined distances. Each element antenna  8  radiates element radio wave  2 E having a phase difference in accordance with the distance between adjacent element antennas  8 . Power transmission antenna  50  as a whole radiates power transmission radio wave  2  (also called power transmission beam) in a power transmission direction. Element radio wave  2 E radiated by element antenna  8  is a part of power transmission radio wave  2 . Element antenna  8  radiates power transmission radio wave  2 . 
     The power transmission direction is a radiation direction in which a power transmission beam is radiated from power transmission antenna  50 . The power transmission direction is determined in a direction toward the direction in which movable body  60  is present (presence direction). Element module  9  adjusts the phase and amplitude of an element transmission signal supplied to element antenna  8 . Transmission signal generator  11  generates a transmission signal having a predetermined frequency to be radiated by each element antenna  8   p  as element radio wave  2 E v . Distribution circuit  12  distributes a transmission signal generated by transmission signal generator  11  and inputs a distributed transmission signal to each element module  9 . Wireless power transmission device  1  includes control device  10  to control each element module  9 . 
     Each element module  9  includes a phase shifter  13  and an amplifier  14 . Phase shifter  13  changes the phase of a transmission signal by a command value. Phase shifter  13  changes the phase discretely at predetermined intervals. The intervals at which the phase is changed, that is, the resolution of the phase is determined by the number of bits that can be used by phase shifter  13  to represent a phase value. It is assumed that phase shifter  13  is a seven-bit phase shifter. Phase shifter  13  rotates the phase at intervals of 360°/2 7 =360°/128=2.8125°. Phase shifter  13  may change the phase continuously. Amplifier  14  amplifies a transmission signal at an instructed amplification factor. Control device  10  has a time device  15 , and movable body  60  has a time device  16 . Time device  15  and time device  16  are synchronized in time with required accuracy. For example, GPS receivers can be used as time device  15  and time device  16 . 
     Movable body  60  includes power reception device  3 , pilot transmitter  5 , a monitor antenna  17 , a detector  18 , an on-board control device  19 , a data storage device  21 , and movable body communication device  20 . Monitor antenna  17  is an antenna for measuring the amplitude and the like of power transmission radio wave  2 . Monitor antenna  17  is a measurement antenna that receives a radio wave radiated by power transmission device  1 . Detector  18  detects a radio wave received by monitor antenna  17  and measures the phase and amplitude of the radio wave. Detector  18  generates detection data  71 . Detection data  71  is data representing the phase and amplitude of a radio wave received by monitor antenna  17 . Detection data  71  is associated with the time of measurement. The time of measurement is time data  72  outputted by time device  16  at the time when measurement is performed. On-board control device  19  controls detector  18  and manages the measured detection data  71 . Data storage device  21  is a storage device to store detection data  71  and the like. Movable body communication device  20  is a communication device that communicates with control device  10 . 
     Wireless power transmission device  1  includes pilot antenna  6  and arrival direction detecting device  7  in order to receive pilot signal  4  and to determine an arrival direction. Pilot antenna  6  receives pilot signal  4  and generates a pilot reception signal. Pilot antenna  6  has directivity. 
     Arrival direction detecting device  7  includes a pilot antenna mount  22 , a pilot antenna controller  23 , and a pilot receiver  24 . Pilot antenna mount  22  supports pilot antenna  6  such that the orientation direction of pilot antenna  6  is changeable. Pilot antenna controller  23  controls pilot antenna mount  22  such that the orientation direction of pilot antenna  6  is oriented in the arrival direction of pilot signal  4 . Pilot receiver  24  receives a pilot reception signal. Pilot receiver  24  processes a pilot reception signal by mono-pulse angle measurement and outputs a mono-pulse error signal representing the difference between the arrival direction of pilot signal  4  and the orientation direction of pilot antenna  6 . Pilot antenna controller  23  determines a command value of the orientation direction of pilot antenna  6  such that the mono-pulse error signal approaches zero. Pilot antenna controller  23  controls pilot antenna mount  22  such that the difference between the command value and the actual orientation direction of pilot antenna  6  approaches zero. The command value of the orientation direction of pilot antenna  6  is parallel to the arrival direction of pilot signal  4  or has a minute difference with the arrival direction. Pilot antenna controller  23  therefore notifies control device  10  of the command value of the orientation direction of pilot antenna  6  as the arrival direction of pilot signal  4 . Control device  10  performs control such that wireless power transmission device  1  radiates power transmission radio wave  2  in a direction toward the arrival direction. Since pilot signal  4  arrives from the direction in which movable body  60  is present, the arrival direction of pilot signal  4  is the presence direction of movable body  60 . Arrival direction detecting device  7  is a presence direction determiner that determines the presence direction that is the direction in which a movable body is present. 
     The common REV method is executed in a state in which the position of a measurement antenna receiving a radio wave radiated by a power transmission antenna is fixed. Thus, the phase shift amount of the part of phase shifters is changed in a state in which a power transmission beam is fixed in the direction in which the measurement antenna is present. Conventionally, the REV method is executed with a fixed direction of a power transmission beam even when the REV method is executed while movable body  60  is moving. When the REV method is executed with a fixed direction of a power transmission beam, the electric power received by the measurement antenna is changed due to the movement of movable body  60  to deteriorate the accuracy of the REV method. 
     Referring to  FIG.  3    and  FIG.  4   , the operation with a power transmission beam tracking a movable body and not tracking a movable body when the REV method is executed for a moving movable body is described. In  FIG.  3   , a power transmission beam does not track a movable body, and in  FIG.  4   , a power transmission beam tracks a movable body. In  FIG.  3    and  FIG.  4   , the temporal change of the direction in which the movable body is present (abbreviated as movable body direction) and the power transmission direction (the direction in which a power transmission beam is radiated) is illustrated on the upper side, and the temporal change of received power strength measured by the measurement antenna is illustrated on the lower side.  FIG.  3    is explained. A phase error of each element is changed as time elapsed after the previous execution of the REV method, and an error is generated in beam formation of a power transmission radio wave to decrease the received power strength. When the received power strength becomes smaller than a threshold, the REV method is executed again. The threshold may be determined in relation to the received power strength obtained by executing the REV method or may be set to a fixed value not depending on the received power strength. The period denoted by reference sign  90  is a period while the REV method is being executed. 
     Movable body direction  91  is changed smoothly with time. In a period while the REV method is not being executed, power transmission direction  92  is controlled such that the difference between power transmission direction  92  and movable body direction  91  is minute. Since phase shifter  13  changes the phase discretely, power transmission direction  92  is changed stepwise. In  FIG.  3   , in period  90  while the REV method is being executed, power transmission direction  92  is fixed to the movable body direction at the start of the REV method. Power transmission direction  92  in period  90  while the REV method is being executed may be fixed to a direction different from the movable body direction at the start of the REV method. In  FIG.  4    in which the power transmission beam tracks the movable body during execution of the REV method, power transmission direction  92 A is changed stepwise such that the difference from movable body direction  91  is reduced also in period  90  while the REV method is being executed. 
     In the REV method, the phase is changed in element radio waves  2 E radiated by some of element antennas  8 . Therefore, received power strength  93  measured by the measurement antenna varies in period  90  while the REV method is being executed. When period  90  while the REV method is being executed ends, the phase error of element radio wave  2 E p  radiated by each element antenna  8   p  is decreased, so that received power strength  93  becomes a value greater than the value before period  90 . 
     In  FIG.  3   , the moving average of received power strength  93  is decreased while varying in period  90  while the REV method is being executed. This is because power transmission direction  93  does not follow movable body direction  91  and therefore power transmission direction  93  deviates from movable body direction  91 . Thus, received power strength  93  is decreased in period  90  while the REV method is being executed. 
     By comparison, in  FIG.  4   , power transmission direction  92 A tracks movable body direction  91 , so that the moving average of received power strength  93 A is not decreased in period  90  while the REV method is being executed. Since the accuracy of adjusting the phase error in the REV method is improved, received power strength  93 A obtained by executing the REV method is greater than received power strength  93 . 
     In  FIG.  3    in which the power transmission direction is fixed during execution of the REV method, since the accuracy of adjusting the phase error in the REV method is low, received power strength  93  obtained by executing the REV method is smaller than received power strength  93 A in  FIG.  4   . Thus, the period until the received power strength reaches the threshold or lower is shorter than when the power transmission direction tracks movable body  60  during execution of the REV method. The cycle of executing the REV method is therefore shorter. Since the power transmission ability is decreased during execution of the REV method, the frequent execution of the REV method causes the deterioration of the power transmission efficiency. 
     In wireless power transmission device  1 , the power transmission beam tracks movable body  60  during execution of the REV method as illustrated in  FIG.  4   . Referring to  FIG.  5   , a functional configuration of wireless power transmission device  1  and movable body  60  is described.  FIG.  5    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the first embodiment. Control device  10  generates a data acquisition command  73  to be sent to movable body  60 . Data acquisition command  73  is a command for instructing on-board control device  19  to acquire electric field change data. The electric field change data is data representing change of the electric field vector measured by monitor antenna  17  that is obtained by executing the REV method. The electric field vector is a vector representing the amplitude and phase of power transmission radio wave  2 . Data acquisition command  73  is transmitted from control device  10  to on-board control device  19  mounted on movable body  60 . Upon receiving data acquisition command  73 , on-board control device  19  sets a measurement period specified by data acquisition command  73 . The measurement period is set in a period in which an REV method scenario  74  (described later) is scheduled to be executed. The measurement period may be one period or may be a plurality of separate periods. Detector  18  measures the electric field vector of a radio wave received by monitor antenna  17  in a period at least including a measurement period. The electric field vector may be measured as a vector represented by amplitude and phase, or only the amplitude of the electric field vector may be measured. The amplitude of the electric field vector is called electric field strength. Data acquisition command  73  may be sent, for example, in each measurement period. 
     REV method scenario  74  is data that defines a pattern of the amount by which the phase is changed (phase shift amount) for each phase shifter  13  in order to execute the REV method. REV method scenario  74  may change the phase shift amounts of phase shifters  13  one by one or may change the phases by the same phase shift amount for a plurality of phase shifters  13 . In REV method scenario  74 , element radio waves  2 E may be radiated from all of element antennas  8  or element radio waves  2 E may be radiated from some of element antennas  8 . Any REV method scenario  74  can be used as long as it defines a phase operating pattern. The phase operating pattern is a pattern that describes operation of changing the phase shift amount of the part of phase shifters  13 . The operation of changing the phase shift amount of the part of phase shifters  13  is repeated while changing the part of phase shifters  13 , and is performed in a state in which at least some element antennas  8  radiate element radio waves  2 E. Phase shifter  13  of which phase shift amount is changed is called operating phase shifter. 
     In wireless power transmission device  1 , the phases of radio waves radiated by the part of element antennas  8  for execution of the REV method are changed while the moving movable body  60  is tracked and the radiation direction is changed to the direction in which movable body  60  is present. The sum of the phase operating amount (direction change phase shift amount) for changing the radiation direction toward the moving movable body  60  and the phase shift amount (operation phase shift amount) defined by REV method scenario  74  is the phase command value of each phase shifter  13 . Control device  10  performs control by giving a command value to each element module  9 , that is, each phase shifter  13  and each amplifier  14 . 
     On-board control device  19  generates detection data  71  by adding time data  72  at a point of time when the electric field vector is measured by detector  18 . Detection data  71  measured by detector  18  during execution of REV method scenario  74  is called REV method run-time radio wave data. Detection data  71  represents change of the electric field vector measured by monitor antenna  17 . Detection data  71  measured at least in a measurement period is stored in data storage device  21 . Detection data  71  measured during execution of REV method scenario  74  is transmitted from on-board control device  19  to control device  10 . Data transmitted from movable body  60  to obtain an element electric field vector by control device  10  is electric field change data. In the first embodiment, detection data  71  that is the REV method run-time radio wave data is electric field change data. 
     In the REV method, in order to equalize (calibrate) the phase references of element modules  9 , monitor antenna  17  measures change of the electric field vector repeatedly while changing the phase shift amount of the part of phase shifters  13  in a state in which at least some element antennas  8  radiate element radio waves  2 E. The phase shift amount is the amount of changing the phase of a signal outputted by phase shifter  13  from the phase of an input signal. The element electric field vector is calculated for each element antenna  8 , from change of the electric field vector. The element electric field vector is an electric field vector generated at the position of monitor antenna  17  by element radio wave  2 E radiated by element antenna  8  supplied with a transmission signal outputted by one element module  9 . Monitor antenna  17  receives element radio wave  2 E to detect the element electric field vector. Element radio wave  2 E p  radiated by each element antenna  p   8  is received by monitor antenna  17  whereby the element electric field vector is detected. 
     Control device  10  calculates a phase shift offset value  77  for equalizing the phase references of phase shifters  13 , from the phase of the element electric field vector for each element antenna  8 . The calculated phase shift offset value  77  is set in each phase shifter  13 . The amplification factor of each amplifier  14  may be adjusted from the amplitude ratio of the element electric field vector for each element antenna  8  such that the amplitude of the element electric field vector is also matched. Only the element electric field phase that is the phase of the element electric field vector may be calculated, instead of the element electric field vector. 
     Control device  10  includes time device  15 , a data storage  25 , an REV method necessary or unnecessary determiner  26 , an REV method executor  27 , a data acquisition command generator  28 , an element electric field calculator  29 , communication device  30 , a phase offset value calculator  31 , a phase offset value setter  32 , a radiation direction determiner  33 , and a radio wave radiation controller  34 . Element electric field calculator  29  includes a measurement data analyzer  35 , an operation phase shift amount acquirer  36 , and an element electric field vector calculator  37 . 
     Data storage  25  stores data necessary for executing the REV method and data necessary for control device  10  to transmit power to movable body  60 . REV method necessary or unnecessary determiner  26  determines whether execution of the REV method is necessary or not. REV method executor  27  controls each element module  9  during execution of the REV method. Data acquisition command generator  28  generates data acquisition command  73  to notify movable body  60  of the start of execution of the REV method. Communication device  30  communicates with movable body communication device  20  included in movable body  60 . Element electric field calculator  29  calculates the element electric field vector generated by element radio wave  2 E p  radiated by each element antenna  8   p  by the REV method. Phase offset value calculator  31  calculates a phase offset value to be set in each phase shifter  13  from the element electric field vector. Radiation direction determiner  33  determines a radiation direction from the arrival direction of pilot signal  4 . Radio wave radiation controller  34  controls each module  9  such that power transmission radio wave  2  is radiated in the radiation direction. The arrival direction is the presence direction that is the direction in which movable body  60  is present. 
     The phase offset value is a value to be subtracted from a phase command value given to phase shifter  1 . Phase shifter  13  changes the phase by the amount obtained by subtracting the phase offset value from the phase command value. Thus, the amount of change of phase in a transmission signal outputted by phase shifter  13  actually is a value obtained by subtracting the phase offset value from the phase command value. The phase offset value is subtracted from the phase command value whereby each element antenna  8   p  can radiate element radio wave  2 E p  having the same phase when the same phase command value is given to each element module  9 . 
     The phase difference between element electric field vectors generated by element radio waves  2 E p  radiated by element antennas  8   p  is measured by the REV method. In the REV method, the phase of element radio wave  2 E radiated by any one of element antennas  8  is changed so that change in amplitude (electric field strength) of the electric field vector of the radio wave received by monitor antenna  17  is measured. Detection data  71  at least including the measured electric field strength is sent to control device  10  by movable body communication device  20 . Time data  72  representing the time of measurement is added to detection data  71 . 
     Control device  10  calculates the phase difference between the element electric field vector of a radio wave radiated by element antenna  8  corresponding to each element module  9  and the electric field vector (composite electric field vector) of power transmission radio wave  2  obtained by synthesizing element radio waves  2 E radiated by all element antennas  8 , from the change of the electric field vector conveyed by the received detection data  71 . Control device  10  calculates a phase offset value to be set in each phase shifter  13 , from the phase difference between the element electric field vector and the composite electric field vector. 
     The phase difference between element electric field vectors generated by element radio waves  2 E p  radiated by element antennas  8   p  is caused by a difference in path length in the inside of wireless power transmission device  1 , a difference in distance between each element antenna  8  and monitor antenna  17 , change in surrounding environment of wireless power transmission device  1 , and the like. The phase difference caused by a difference in path length in the inside of wireless power transmission device  1  is obtained and corrected before wireless power transmission device  1  is used. A phase difference is changed with the temperature of wireless power transmission device  1  because a circuit for radio wave frequency includes phase error components having such as a difference in temperature characteristics, in addition to the path length difference. The change in surrounding environment of wireless power transmission device  1  is, for example, the influence of structures existing in the surroundings of wireless power transmission device  1  or change in state of the air through which power transmission radio wave  2  is transmitted. A phase difference caused by the change in surrounding environment of wireless power transmission device  1  deteriorates the power transmission efficiency. When the power transmission efficiency is deteriorated, the REV method is executed to obtain and correct the phase difference. By doing so, the power transmission efficiency of wireless power transmission device  1  can be recovered to the original value. 
     Data storage  25  stores REV method scenario  74 , detection data  71 , phase operation data  75 , element electric field vector  76 , phase offset value  77 , arrival direction data  78 , radiation direction data  79 , and radiation command value  80 . 
     REV method scenario  74  defines the order of phase shifters  13  for which the phase shift amount is changed for executing the REV method and a phase operating pattern that is a pattern representing temporal change in which the phase shift amount is changed for each phase shifter  13 . The sum of the direction change phase shift amount for transmitting power in the power transmission direction and the operation phase shift amount determined from REV method scenario  74  is the phase command value of each phase shifter  13 . 
     The phase operating pattern defines a sequence of changing the phase shift amount of each phase shifter  13  by a relative time from the start of REV method scenario  74 . Change of the phase shift amount of each phase shifter  13  may be represented, for each phase shifter  13 , by a relative time from the start of a period in which the phase shift amount is changed in phase shifter  13 . In general, in REV method scenario  74 , the phase operating pattern is represented by one or more reference events with a designated time and a non-reference event in which the time is represented by a relative time from any one reference event. In the REV method scenario, a phase operating pattern may be represented with a higher degree of freedom, for example, by defining only the order of events as a phase operating pattern. In REV method scenario  74  used in the present embodiment, the start is a reference event and other events are non-reference events. 
     Data acquisition command  73  is a command to notify on-board control device  19  of a measurement period that is a period in which detector  18  mounted on movable body  60  measures detection data  71 . Data acquisition command  73  represents the measurement period, for example, by the start time and the elapsed time from the start time. The measurement period may be represented by the start time and the end time. Data acquisition command  73  may be a command sent at the timings of the start and the end of the measurement period. 
     Detection data  71  is data representing the electric field vector generated by detector  18  with the time. Detection data  71  is measured at predetermined time intervals. Phase operation data  75  is data representing the operation phase shift amount in each time interval of phase shifter  13  that is changed in accordance with REV method scenario  74 . 
     Element electric field vector  76  is data representing the electric field vector generated by element radio wave  2 E p  radiated by element antenna  8   p  at the position where monitor antenna  17  is present. As is described later, element electric field calculator  29  calculates an element electric field phase that is the phase of the element electric field vector and an element electric field amplitude that is the amplitude of the element electric field vector. The element electric field calculator may calculate only an element electric field phase. 
     Phase offset value  77  is the phase shift amount, that is, a numerical value subtracted from the phase command value. Phase shift offset value  77  is set in each phase shifter  13 . Each phase shifter  13  changes the phase by the phase shift amount obtained by subtracting phase offset value  77  from the phase command value. By doing so, when the same phase command value is given to each phase shifter  13 , the phase of element electric field vector  27  generated by element radio wave  2 E p  radiated by each element antenna  8   p  becomes equal. Phase offset value  77  is calculated as a difference of the element electric field phase for each element module  9 . Phase offset value  77  is data for equalizing the phase references of element modules  9  that are obtained based on the element electric field phases for element modules  9 . To calculate phase offset value  77 , it is necessary to calculate the element electric filed phase. When the element electric field phase can be calculated, phase offset value  77  can be calculated. 
     In order to equalize the phase references of element modules  9 , a method different from the method of setting a phase offset value in phase shifter  13  may be used. This is applicable to the other embodiments. 
     Arrival direction data  78  is data representing the direction in which pilot signal  4  arrives. Arrival direction data  78  is obtained by arrival direction detecting device  7  from the pilot reception signal by the mono-pulse angle measurement method. Radiation direction data  79  is data that specifies the direction of a radio wave radiated from power transmission antenna  50 . Radiation command value  80  is data representing a command value to instruct each phase shifter  13  and each amplifier  14  so that a radio wave can be radiated in the direction indicated by radiation direction data  79 . Radiation command value  80  is sent as a power transmission control signal to wireless power transmission device  1 . 
     REV method necessary or unnecessary determiner  26  determines whether execution of the REV method is necessary or not, from detection data  71  sent from movable body  60  periodically. Detection data  71  includes a received power value that is the value of electric power received by movable body  60 . REV method necessary or unnecessary determiner  26  determines that execution of the REV method is necessary when the received power value at the same distance to movable body  60  is decreased to a value smaller than a predetermined threshold. It is determined that execution of the REV method is necessary also when a predetermined time has elapsed since the previous execution of the REV method. Whether execution of the REV method is necessary or not may be determined by either decrease of the received power value to a value less than a threshold or the elapse of time. 
     REV method executor  27  changes the operation phase shift amount of phase shifter  13  specified by REV method scenario  74  and generates phase operation data  75  that is a record of the result of change of the operation phase shift amount. REV method executor  27  is a REV method phase controller that changes the phase of a transmission signal with the phase shift amount obtained by adding the operation phase shift amount to the direction change phase shift amount for the operating phase shifter, based on the REV method scenario. REV method executor  27  is also a phase operation recorder that generates phase operation data  75  to record temporal change of the operation phase shift amount of phase shifter  13  that changes based on the REV method scenario. REV method scenario  74  may be written in a program that implements REV method executor  27 , instead of being stored in data storage  25 . 
     Data acquisition command generator  28  generates data acquisition command  73 . Communication device  30  sends data acquisition command  73  to on-board control device  19  and receives detection data  71  sent from on-board control device  19 . Movable body communication device  20  included in movable body  60  receives data acquisition command  73  sent by control device  10  and sends detection data  71  to control device  10 . 
     Element electric field calculator  29  calculates element electric field vector  76  of each phase shifter  13 , based on REV method scenario  74 , phase operation data  75 , and detection data  71 . The method of calculating element electric field vector  76  is a conventional technique. For example, this technique is described in PTL 2. For example, the element electric field vector is calculated from the operation phase shift amount recorded in phase operation data  75  at the point of time when the amplitude of the electric field vector recorded in detection data  71  is largest or smallest and the ratio between the maximum value and the minimum value of the amplitude of the electric field vector. Element electric field calculator  29  is an REV method analyzer that obtains the element electric field phase for each element module  9 . The internal configuration of element electric field calculator  29  is described later. Phase operation data  75  is generated based on REV method scenario  74 . Element electric field calculator  29  therefore calculates element electric field vector  76  of each phase shifter  13 , based on REV method scenario  74  and detection data  71 . 
     Phase offset value calculator  31  calculates phase offset value  77  for each phase shifter  13  from element electric field vector  76  of each phase shifter  13 . Phase offset value setter  32  sets phase offset value  77  for each phase shifter  13 . Phase offset value calculator  31  and phase offset value setter  32  constitute a phase reference adjuster that equalizes the phase references of transmission signals outputted by element modules  9  based on the element electric field phases. 
     Radiation direction determiner  33  obtains a radiation direction based on arrival direction data  78  and sets the radiation direction in radiation direction data  79 . Radio wave radiation controller  34  generates radiation command value  80  based on radiation direction data  79 . When the radiation direction is not determined, that is, when radiation direction data  79  is not set, radio wave radiation controller  34  does not generate radiation command value  80 . Radio wave radiation controller  34  is a radiation direction changer that directs the radiation direction of power transmission antenna  50  to the presence direction. 
     As illustrated in  FIG.  5   , data storage device  21  mounted on movable body  60  stores measurement period data  70  and detection data  71 . Measurement period data  70  is data representing a period in which detection data  71  is recorded. Measurement period data  70  is specified by data acquisition command  73  sent from control device  10 . Detection data  71  is data representing the electric field vector measured by monitor antenna  17  in a measurement period specified by measurement period data  70  and associated with time data  72  at the point of time when the electric field vector is measured. 
     On-board control device  19  includes time device  16 , a detector controller  61 , a detection data time adder  62 , a data acquisition command interpreter  63 , and a transmission data generator  64 . Detection data time adder  62  adds time data  72  of the time when on-board control device  19  receives detection data  71  to detection data  71  outputted by detector  18 . 
     Data acquisition command interpreter  63  extracts measurement period data  70  from data acquisition command  73  and stores the extracted measurement period data  70  into data storage device  21 . Detector controller  61  controls detector  18  such that detection data  71  is generated in the measurement period specified by measurement period data  70 . Detection data  71  is stored in data storage device  21 . 
     Transmission data generator  64  generates detection data  71  to be sent by compressing detection data  71  in the measurement period defined by measurement period data  70 . Movable body communication device  20  receives data acquisition command  73  and sends detection data  71  generated by transmission data generator  64  to control device  10 . 
     Element electric field calculator  29  includes measurement data analyzer  35 , operation phase shift amount acquirer  36 , and element electric field vector calculator  37 . Measurement data analyzer  35  analyzes detection data  71  sent from on-board control device  19  and detects the time when the electric field strength is largest, the time when the electric field strength is smallest, and the maximum value and the minimum value of the electric field strength, for each measurement period. Operation phase shift amount acquirer  36  refers to phase operation data  75  by the times when the electric field strength is largest or smallest to obtain the operation phase shift amount of the operating phase shifter for each measurement period. The time when the electric field strength is largest or smallest is the time to obtain the operation phase shift amount and is therefore also called the phase shift amount detection time. 
     Element electric field vector calculator  37  calculates the element electric field vector for each element module  9  based on the operation phase shift amount of each phase shifter  13 . When the operation phase shift amount for a single phase shifters  13  is changed in REV method scenario  74 , the element electric field vector can be calculated from the operation phase shift amount of each phase shifter  13  and the ratio between the maximum value and the minimum value of the electric field strength. When the operation phase shift amounts are measured by changing simultaneously the operation phase shift amounts for a plurality of phase shifters  13 , the element electric field vector for each element module  9  can be calculated, for example, by solving simultaneous equations. 
     In order to obtain the operation phase shift amount of phase shifter  13  from the phase shift amount detection time, REV method scenario  74  may be referred to, although referring to phase operation data  75  is more accurate. In this case, the relative time is obtained by subtracting the start time of REV method scenario  74  from the phase shift amount detection time. The change pattern of the operation phase shift amount of each phase shifter  13  defined by the relative time from the start of REV method scenario  74  is referred to by the relative time to obtain the operation phase shift amount of phase shifter  13  at the phase shift amount detection time. The relative time written in REV method scenario  74  may be converted into the absolute time (time), and the REV method scenario converted in the absolute time may be referred to by the phase shift amount detection time. 
     How the electric power received by power reception device  3  mounted on movable body  60  is changed with the movement of movable body  60  is studied. The following is assumed. 
     (A) Power transmission antenna  50  has element antennas  8  arranged linearly in one dimension. 
     (B) Electric power transmitted by power transmission antenna  50  is calculated with a distance at which a far field is established. 
     (C) Change in power transmission direction in a plane including the direction in which element antennas  8  are arranged and the front direction of power transmission antenna  50  is studied. When the power transmission direction is matched with the front direction of power transmission antenna  50 , the angle of the power transmission direction is zero degrees. 
     (D) Assuming that change in distance between wireless power transmission device  1  and power reception device  3  is small, change in electric power received by power reception device  3  for the change in distance is not taken into consideration. 
     Since the distance between wireless power transmission device  1  and power reception device  3  is a distance at which a far field is established, change in distance between wireless power transmission device  1  and power reception device  3  is generated similarly in all element antennas  8 . Thus, change in distance between wireless power transmission device  1  and power reception device  3  does not change the phase difference of element radio wave  2 E p  radiated by each element antenna  8   p . 
     The following variables are defined as variables representing the characteristics of power transmission antenna  50 . 
     N: the number of element antennas  8  included in power transmission antenna  50 . 
     Nm: the middle number of N. Nm=(N+1)/2. 
     f: the frequency of power transmission radio wave  2  transmitted. 
     λ: the wavelength of power transmission radio wave  2  transmitted. λ=c/(2π*f). c is speed of light. 
     L: the distance between element antennas  8 . 
     nd: the number of phases that can be changed by phase shifter  13 . 
     θd: the interval at which the phase is changed by phase shifter  13 . θd=2π/nd [rad] 
     p: the subscript for element antenna  8 . Adjacent element antennas  8  are set to have numbers p in series. 
     φp: the phase error of element radio wave  2 E p  radiated by element antenna  8   p  numbered p. The adjustment target in the REV method. 
     ψ: the power transmission direction of power transmission antenna  50 . 
     θ p : the direction change phase shift amount for element antenna  8  numbered p at the time of power transmission direction ψ. 
     k p : the phase shift amount for phase shifter  13  numbered p for the direction change phase shift amount θ p . 
     δ: deviation angle from power transmission direction ψ. 
     ε: the phase difference between the element electric field vectors generated by element radio waves  2 E radiated by adjacent element antennas  8  that is detected in the direction at deviation angle S. 
     γ: the ratio of the amplitude of the electric field vector detected in the direction at deviation angle δ to the amplitude of the electric field vector detected in the power transmission direction ψ. Called the amplitude attenuation ratio. 
     When power is transmitted in the power transmission direction ψ, the direction change phase shift amount θ p  of element radio wave  2 E p  radiated by each element antenna  8   p  is determined as follows. For each phase shifter  13   p , the phase error φp=0 is assumed. 
       θ p (2*π)*( p−Nm )*( L /λ)*sin(ψ) p= 1, . . . , N   (1)
 
     Since the phase is changed every θd in phase shifter  13 , kp is determined as follows such that |θ p −k p *θd|≤(θd/2) is satisfied. Here, int(X) is a function that returns the maximum integer equal to or smaller than a real number X. 
         k   p =int((θ p   /θd )+0.5)  (2)
 
     The phase difference ε between the element electric field vectors generated by element radio waves  2 E radiated by adjacent element antennas  8  that is detected in a direction (ψ+δ) deviated from power transmission direction ψ by angle δ is determined as follows. 
       ε=(2*π)*( L /λ)*(sin(ψ+δ)−sin(ψ))  (3)
 
     Equation (3) is approximated by sin(δ)≈δ and cos(δ)≈1 as follows, assuming that δ is minute. 
       ε=(2*π)*( L /λ)*cos(ψ)*δ  (4)
 
     The amplitude attenuation ratio γ, which is the value obtained by dividing the amplitude of the electric field vector detected in the direction (ψ+δ) by the amplitude of the electric field vector detected in the power transmission direction ψ, can be calculated as follows. It is assumed that deterioration in power transmission efficiency caused by changing the phase every θd in phase shifter  13  is zero in the power transmission direction ψ. 
       γ=(1/ N )*Σexp( j *( p−Nm )*ε)  (5)
 
     In equation (5) and the like, Σ means summation with p=1, . . . , N. In equation (5), (p−Nm)*ε is set instead of p*ε in order to prevent the phase of the composite electric field vector from changing with the phase difference ε. Based on equation (5), the absolute value |γ| of γ can be calculated as follows. 
       |γ|=(1/ N )*√((Σ cos(( P−Nm )*ε)) 2 +(Σ sin(( p−Nm )*ε)) 2 )  (6)
 
     A case where power transmission antenna  50  is a phased array antenna with N=10, f=5 GHz, X=60 mm, L=60 mm, nd=128, and θd=2.8125 degrees is studied.  FIG.  6    illustrates graphs representing change of the amplitude attenuation ratio γ to change of deviation angle δ when the power transmission direction ψ is set to be 0 degrees, 30 degrees, and 60 degrees. The graph satisfying ψ=0 degrees is depicted by a solid line, the graph satisfying ψ=30 degrees is depicted by a broken line, and the graph satisfying ψ=60 degrees is depicted by a long and short dashed line. When ψ is set to be 0 degrees, the half-width (full width at half maximum) in which the amplitude attenuates to half is approximately 6.8 degrees. As ψ is increased, the half-width is increased. When ψ is set to be 30 degrees, the half-width is approximately 8.0 degrees. When ψ is set to be 60 degrees, the half-width is approximately 14.1 degrees. When ψ is set to exceed 30 degrees, the degree of increase of half-width to the increase of ψ is increased. The width of the power transmission beam is larger on the side where deviation angle δ&gt;0 is satisfied than on the side where δ&lt;0 is satisfied. The side satisfying δ&gt;0 is the side on which the angle with respect to the front direction is larger. 
     The following variables are defined in order to describe the conditions in which power is transmitted to the moving movable body  60 . It is assumed that power transmission antenna  50  is installed such that the front direction is directed to the zenith. 
     ψ: the direction from wireless power transmission device  1  toward movable body  60 . ψ=0 degrees when directed to the zenith. When ψ&gt;0, movable body  60  is present in front of wireless power transmission device  1 . ψ is called the altitude angle. 
     ψ 0 : the power transmission direction ψ at the start of the REV method. 
     G: the distance from wireless power transmission device  1  to movable body  60 . 
     G 0 : the distance G at the start of the REV method. 
     V 0 : the speed of movable body  60 . Constant value. 
     ξ 0 : the angle difference between the moving direction of movable body  60  and the direction toward the zenith. Constant value. ξ 0 =0 degrees when directed to the zenith. 
     t: the elapsed time from the start of the REV method. 
     P t : the position of movable body  60  at time t. The position of wireless power transmission device  1  is used as a reference. 
     P 0 : the position of movable body  60  at the start of the REV method (t=0). 
     The following is satisfied for the distance to movable body  60  and the direction.  FIG.  7    illustrates variables representing the positional relation between the movable body and the wireless power transmission device. In  FIG.  7   , the direction toward the zenith is depicted by a long and short dashed line. Equation (7) is an equation for the height of movable body  60 , and Equation (8) is an equation for the distance in the horizontal direction of movable body  60 . 
         G   0 *sin(ψ 0 )+ V   0   *t *sin(ξ 0 )= G *sin(ψ)  (7)
 
         G   0 *cos(ψ 0 )+ V   0   *t *cos(ξ 0 )= G *cos(ψ)  (8)
 
     Based on equation (7) and equation (8), G and ψ can be calculated by the following equations. 
         G =√( G   0   2 +2* G   0   *V   0   *t *cos(ξ 0 −ψ 0 )+( V   0   *t ) 2 )  (9)
 
       ψ=sin −1 (( G   0 *sin(ψ 0 )+ V   0   *t *sin(ξ 0 ))/ G )  (10)
 
     The variables used for explaining the process of the REV method are defined as follows. 
     Td: the length of time in which element radio wave  2 E radiated by element antenna  8  has the specified operation phase shift amount specified during execution of the REV method. 
     m: the cumulative number of times the operation phase shift amount is changed in each element module  9  since the start of the REV method.
         t is m*Td.       

     θ rp : the phase command value for phase shifter  13  numbered q during execution of the REV method. 
     q: the number of element antenna  8  in which the phase is to be changed in the REV method. 
     r: the number that specifies the phase to be changed in element antenna  8  numbered q in the REV method. 
     E 0 : the amplitude of the element electric field vector generated by element radio wave  2 E radiated by one element antenna  8 . 
     E p : the element electric field vector at the position of power reception device  3  that is generated by element radio wave  2 E p  radiated by element antenna  8   p  numbered p. 
     Esum: the electric field vector at the position of power reception device  3  that is generated by element radio waves  2 E radiated by all element antennas  8 . 
     θ sum : the phase of electric field vector Esum. 
     In the REV method, the phase is changed by r*θd in the order of r=1, nd every time Td in element antenna  8   q  numbered q in the order of q=1, . . . , N. Furthermore, the phase of element radio wave  2 E p  radiated by each element antenna  8   p  is controlled such that element radio wave  2 E p  can be radiated toward the power transmission direction ψ. The phase command value θ m  for each phase shifter  13  at time t=m*Td is determined as follows. k p *θd indicated in equation (11-1) and equation (11-2) is the direction change phase shift amount, and r*θd is the operation phase shift amount. k p  can be calculated from equation (2) and equation (1). ψ can be calculated from equation (10) and equation (9). 
       When  p≠q, θ   rp   =k   p   *θd   (11-1)
 
       When  p=q, θ   rp =( k   p   +r )*θ d   (11-2)
 
     Here, q and r have the following relation with m. mod(X, Y) is a function that returns the remainder when a natural number X is divided by a natural number Y. q is incremented by one every time m is increased by nd. r is incremented by one every time m is increased by one. When r=nd, r=1 is set. 
         q =int(( m− 1)/ nd )+1  (12)
 
         r =mod(( m− 1), nd )+1  (13)
 
     Here, a simulation is conducted in a case where the direction change phase shift amount is updated every 10 msec. 
     The phase of element radio wave  2 E p  radiated by element antenna  8   p  numbered p has the following three kinds of differences with respect to the direction change phase shift amount θ p . 
     (A) the phase error φp of element radio wave  2 E p  radiated by element antenna  8   p  numbered p. 
     (B) the error of approximating θp by an integer multiple of θd. 
     (C) the operation phase shift amount r*θd in executing the REV method. 
     The element electric field vectors E p  and Esum therefore can be calculated as follows. 
         E   p   =E   0 *exp( j (φ p+θ   rp −θ p ))  (14)
 
         E sum=Σ E   p   =E   0 *Σexp( j (φ p+θ   rp −θ p )  (15)
 
       | E sum|=√/((Σ cos(φ p+θ   rp −θ p )) 2 +(Σ sin(φ p+θ   rp −θ p )) 2 )  (16)
 
       θsum=sin −1 (Σ sin(φ p+θ   rp −θ p )/| E sum|)  (17)
 
     A comparative example in which movable body  60  is not tracked during execution of the REV method is studied. The following variables are defined. 
     θ 0p : the direction change phase shift amount for element antenna  8  numbered p at the time of power transmission direction ψ 0 . 
     k 0p : the phase shift amount for phase shifter  13  numbered p for the direction change phase shift amount θ 0p . 
     ε2: the phase difference between the element electric field vectors generated by element radio waves  2 E p  radiated by adjacent element antennas  8   p  that is detected in the power transmission direction ψ. 
     E2 p : the element electric field vector generated by element radio wave  2 E p  radiated by element antenna  8   p  numbered p when movable body  60  is not tracked during execution of the REV method. 
     E2sum: the electric field vectors generated by element radio waves  2 E radiated by all element antennas  8  when movable body  60  is not tracked during execution of the REV method. 
     θ2sum: the phase of electric field vector E2sum. 
     θ 0p , k 0p , and ε 2  can be calculated as follows. 
       θ 0p =(2*π)*( p−Nm )*( L /λ)*sin(ψ 0 ) p= 1, . . . , N   (18)
 
         k   0p =int((θ 0p   /θd )+0.5)  (19)
 
       ε2=(2*π)*( L /λ)*(sin(ψ)−sin(ψ 0 ))  (20)
 
     Equation (7) is substituted into equation (20) as follows. 
       ε2=(2*π)*( L /λ)*(1/ G )*(( G   0   −G )*sin(ψ 0 )+ V   0   *m*Td *sin(ξ 0 ))  (21)
 
     When movable body  60  is not tracked during execution of the REV method, the phase command value θ rp  for each phase shifter  13  at time t=m*Td is determined as follows. 
       When  p≠q, θ   rp   =k   0p   *θd   (22-1)
 
       When  p=q, θ   rp =( k   0p   +r )*θ d   (22-2)
 
     E2 p  and E2sum can be calculated by the following equations. 
     
       
         
           
             
               
                 
                   
                     E 
                     ⁢ 
                     
                       2 
                       P 
                     
                   
                   = 
                   
                     
                       E 
                       0 
                     
                     * 
                     exp 
                     ⁢ 
                        
                     
                       ( 
                       
                         j 
                         ⁢ 
                         
                           ( 
                           
                             
                               φ 
                               ⁢ 
                               p 
                             
                             + 
                             
                               θ 
                               rp 
                             
                             - 
                             
                               θ 
                               
                                 0 
                                 ⁢ 
                                 p 
                               
                             
                             + 
                             
                               
                                 ( 
                                 
                                   p 
                                   - 
                                   Nm 
                                 
                                 ) 
                               
                               * 
                               ε2 
                             
                           
                           ) 
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   23 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   
                     
                       
                         
                           E 
                           ⁢ 
                           2 
                           ⁢ 
                              
                           sum 
                         
                         = 
                           
                         
                           Σ 
                           ⁢ 
                           E 
                           ⁢ 
                           
                             2 
                             p 
                           
                         
                       
                     
                   
                   
                     
                       
                         = 
                           
                         
                           
                             E 
                             0 
                           
                           * 
                           Σ 
                           ⁢ 
                              
                           exp 
                           ⁢ 
                              
                           
                             ( 
                             
                               j 
                               ⁡ 
                               ( 
                               
                                 
                                   φ 
                                   ⁢ 
                                   p 
                                 
                                 + 
                                 
                                   θ 
                                   rp 
                                 
                                 - 
                                 
                                   θ 
                                   
                                     0 
                                     ⁢ 
                                     p 
                                   
                                 
                                 + 
                                 
                                   
                                     ( 
                                     
                                       p 
                                       - 
                                       Nm 
                                     
                                     ) 
                                   
                                   * 
                                   ε2 
                                 
                               
                               ) 
                             
                           
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   24 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   
                     
                       
                         
                           
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                             ⁢ 
                             2 
                             ⁢ 
                               
                             sum 
                           
                           
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                         = 
                           
                         
                           
                             ( 
                             
                               
                                 ( 
                                 
                                   Σ 
                                   ⁢ 
                                      
                                   cos 
                                   ⁢ 
                                      
                                   
                                     ( 
                                     
                                       
                                         φ 
                                         ⁢ 
                                         p 
                                       
                                       + 
                                       
                                         θ 
                                         rp 
                                       
                                       - 
                                       
                                         θ 
                                         
                                           0 
                                           ⁢ 
                                           p 
                                         
                                       
                                       + 
                                       
                                         
                                           ( 
                                           
                                             p 
                                             - 
                                             Nm 
                                           
                                           ) 
                                         
                                         * 
                                         ε 
                                         ⁢ 
                                         2 
                                       
                                     
                                     ) 
                                   
                                 
                                 ) 
                               
                               2 
                             
                           
                         
                       
                     
                   
                   
                     
                       
                         
                           + 
                             
                           
                             
                               ( 
                               
                                 Σ 
                                 ⁢ 
                                    
                                 sin 
                                 ⁢ 
                                    
                                 
                                   ( 
                                   
                                     
                                       φ 
                                       ⁢ 
                                       p 
                                     
                                     + 
                                     
                                       θ 
                                       rp 
                                     
                                     - 
                                     
                                       θ 
                                       
                                         0 
                                         ⁢ 
                                         p 
                                       
                                     
                                     + 
                                     
                                       
                                         ( 
                                         
                                           p 
                                           - 
                                           Nm 
                                         
                                         ) 
                                       
                                       * 
                                       ε 
                                       ⁢ 
                                       2 
                                     
                                   
                                   ) 
                                 
                               
                               ) 
                             
                             2 
                           
                         
                         ) 
                       
                     
                   
                 
               
               
                 
                   ( 
                   25 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   
                     θ2 
                     ⁢ 
                        
                     sum 
                   
                   = 
                   
                     
                       sin 
                       
                         - 
                         1 
                       
                     
                     ( 
                     
                       Σ 
                       ⁢ 
                          
                       sin 
                       ⁢ 
                          
                       
                         
                           ( 
                           
                             
                               φ 
                               ⁢ 
                               p 
                             
                             + 
                             
                               θ 
                               rp 
                             
                             - 
                             
                               θ 
                               
                                 0 
                                 ⁢ 
                                 p 
                               
                             
                             + 
                             
                               
                                 ( 
                                 
                                   p 
                                   - 
                                   Nm 
                                 
                                 ) 
                               
                               * 
                               ε 
                               ⁢ 
                               2 
                             
                           
                           ) 
                         
                         / 
                         
                           
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                             ⁢ 
                                
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                     ) 
                   
                 
               
               
                 
                   ( 
                   26 
                   ) 
                 
               
             
           
         
       
     
     Power transmission antenna  50  has element antennas  8  arranged in two dimensions. A case where the direction of arrangement of element antennas  8  and the locus of movable body  60  are not on a single plane is studied. Here, it is assumed that the directions in which element antennas  8  are arranged in power transmission antenna  50  being matched with a south-north direction and an east-west direction. The following variables are defined. Movable body  60  moves on a straight line extending in a predetermined direction. 
     ψ AZ : the azimuth angle component of the direction from wireless power transmission device  1  toward movable body  60 . ψ AZ =0 when directed to the north. ψ AZ &gt;0 clockwise. Called azimuth angle. 
     ψ EL : the elevation angle component of the direction from wireless power transmission device  1  toward movable body  60 . ψ EL =0 when directed to the zenith. Called altitude angle. 
     ψ AZ0 : the azimuth angle component of the direction from wireless power transmission device  1  toward movable body  60  at the start of the REV method. 
     ψ EL0 : the altitude angle of the direction from wireless power transmission device  1  toward movable body  60  at the start of the REV method. 
     V 0 : the speed of movable body  60 . Constant value. 
     ξ AZ0 : the angle difference between the moving direction of movable body  60  and the south-north direction. 
     ξ EL0 : the angle difference between the moving direction of movable body  60  and the direction toward the zenith. 
     The following is satisfied for the distance to movable body  60  and the direction. For the position of movable body  60  in the south-north direction, equation (27) is satisfied. 
     
       
         
           
             
               
                 
                   
                     
                       
                         
                           G 
                           0 
                         
                         * 
                         sin 
                         ⁢ 
                            
                         
                           ( 
                           
                             ψ 
                             
                               EL 
                               ⁢ 
                               0 
                             
                           
                           ) 
                         
                         * 
                           
                         cos 
                         ⁢ 
                            
                         
                           ( 
                           
                             ψ 
                             
                               AZ 
                               ⁢ 
                               0 
                             
                           
                           ) 
                         
                       
                     
                   
                   
                     
                       
                         
                           + 
                           
                             V 
                             0 
                           
                         
                         * 
                         t 
                         * 
                         sin 
                         ⁢ 
                            
                         
                           ( 
                           
                             ξ 
                             
                               EL 
                               ⁢ 
                               0 
                             
                           
                           ) 
                         
                         * 
                         cos 
                         ⁢ 
                         
                           ( 
                           
                             ξ 
                             
                               AZ 
                               ⁢ 
                               0 
                             
                           
                           ) 
                         
                       
                     
                   
                   
                     
                       
                         = 
                         
                           G 
                           * 
                           sin 
                           ⁢ 
                              
                           
                             ( 
                             
                               ψ 
                               EL 
                             
                             ) 
                           
                           * 
                           cos 
                           ⁢ 
                              
                           
                             ( 
                             
                               ψ 
                               AZ 
                             
                             ) 
                           
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   27 
                   ) 
                 
               
             
           
         
       
     
     For the position of movable body  60  in the east-west direction, equation (28) is satisfied. 
     
       
         
           
             
               
                 
                   
                     
                       
                         
                           G 
                           0 
                         
                         * 
                         sin 
                         ⁢ 
                            
                         
                           ( 
                           
                             ψ 
                             
                               EL 
                               ⁢ 
                               0 
                             
                           
                           ) 
                         
                         * 
                           
                         sin 
                         ⁢ 
                         
                           ( 
                           
                             ψ 
                             
                               AZ 
                               ⁢ 
                               0 
                             
                           
                           ) 
                         
                       
                     
                   
                   
                     
                       
                         
                           + 
                           
                             V 
                             0 
                           
                         
                         * 
                         t 
                         * 
                         sin 
                         ⁢ 
                            
                         
                           ( 
                           
                             ξ 
                             
                               EL 
                               ⁢ 
                               0 
                             
                           
                           ) 
                         
                         * 
                         sin 
                         ⁢ 
                            
                         
                           ( 
                           
                             ξ 
                             
                               AZ 
                               ⁢ 
                               0 
                             
                           
                           ) 
                         
                       
                     
                   
                   
                     
                       
                         = 
                         
                           G 
                           * 
                           sin 
                           ⁢ 
                              
                           
                             ( 
                             
                               ψ 
                               EL 
                             
                             ) 
                           
                           * 
                           sin 
                           ⁢ 
                              
                           
                             ( 
                             
                               ψ 
                               AZ 
                             
                             ) 
                           
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   28 
                   ) 
                 
               
             
           
         
       
     
     For the altitude where movable body  60  is present, equation (29) is satisfied. 
         G   0 *cos(ψ EL0 )+ V   0   *t *cos(ξ EL0 )= G *cos(ψ EL )  (29)
 
     The following is obtained from equations (27) to (29). 
     
       
         
           
             
               
                 
                   
                     
                       
                         G 
                         = 
                           
                         
                           
                             ( 
                             
                               
                                 G 
                                 0 
                                 2 
                               
                               + 
                               
                                 
                                   ( 
                                   
                                     
                                       V 
                                       0 
                                     
                                     * 
                                     t 
                                   
                                   ) 
                                 
                                 2 
                               
                             
                           
                         
                       
                     
                   
                   
                     
                       
                         
                           + 
                             
                           2 
                         
                         * 
                         
                           G 
                           0 
                         
                         * 
                         
                           V 
                           0 
                         
                         * 
                         t 
                       
                     
                   
                   
                     
                       
                         * 
                           
                         
                           ( 
                           
                             sin 
                             ⁢ 
                                
                             
                               ( 
                               
                                 ψ 
                                 
                                   EL 
                                   ⁢ 
                                   0 
                                 
                               
                               ) 
                             
                             * 
                             sin 
                             ⁢ 
                                
                             
                               ( 
                               
                                 ξ 
                                 
                                   EL 
                                   ⁢ 
                                   0 
                                 
                               
                               ) 
                             
                             * 
                             cos 
                             ⁢ 
                                
                             
                               ( 
                               
                                 
                                   ψ 
                                   
                                     AZ 
                                     ⁢ 
                                     0 
                                   
                                 
                                 - 
                                 
                                   ξ 
                                   
                                     AZ 
                                     ⁢ 
                                     0 
                                   
                                 
                               
                               ) 
                             
                           
                         
                       
                     
                   
                   
                     
                       
                         
                           
                             
                               + 
                                 
                               cos 
                             
                             ⁢ 
                                
                             
                               ( 
                               
                                 ψ 
                                 
                                   EL 
                                   ⁢ 
                                   0 
                                 
                               
                               ) 
                             
                             * 
                             cos 
                             ⁢ 
                             
                               ( 
                               
                                 ξ 
                                 
                                   EL 
                                   ⁢ 
                                   0 
                                 
                               
                               ) 
                             
                           
                           ) 
                         
                         ) 
                       
                     
                   
                 
               
               
                 
                   ( 
                   30 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   
                     
                       
                         
                           ψ 
                           EL 
                         
                         = 
                           
                         
                           
                             sin 
                             
                               - 
                               1 
                             
                           
                           ( 
                           
                             
                               ( 
                               
                                 ( 
                                 
                                   
                                     G 
                                     2 
                                   
                                   - 
                                   
                                     ( 
                                     
                                       
                                         G 
                                         0 
                                       
                                       * 
                                       cos 
                                       ⁢ 
                                          
                                       
                                         ( 
                                         
                                           ψ 
                                           
                                             EL 
                                             ⁢ 
                                             0 
                                           
                                         
                                         ) 
                                       
                                     
                                   
                                 
                               
                             
                           
                         
                       
                     
                   
                   
                     
                       
                         
                           
                             
                               
                                   
                                 
                                   
                                     + 
                                     
                                       V 
                                       0 
                                     
                                   
                                   * 
                                   t 
                                   * 
                                   cos 
                                   ⁢ 
                                      
                                   
                                     ( 
                                     
                                       ξ 
                                       
                                         EL 
                                         ⁢ 
                                         0 
                                       
                                     
                                     ) 
                                   
                                 
                                 ) 
                               
                               2 
                             
                             ) 
                           
                           / 
                           G 
                         
                         ) 
                       
                     
                   
                 
               
               
                 
                   ( 
                   31 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   
                     
                       
                         
                           ψ 
                           AZ 
                         
                         = 
                           
                         
                           
                             sin 
                             
                               - 
                               1 
                             
                           
                           ( 
                           
                             
                               ( 
                               
                                 ( 
                                 
                                   
                                     G 
                                     0 
                                   
                                   * 
                                   sin 
                                   ⁢ 
                                      
                                   
                                     ( 
                                     
                                       ψ 
                                       
                                         EL 
                                         ⁢ 
                                         0 
                                       
                                     
                                     ) 
                                   
                                   * 
                                   
                                     sin 
                                     ⁡ 
                                     ( 
                                     
                                       ψ 
                                       
                                         AZ 
                                         ⁢ 
                                         0 
                                       
                                     
                                     ) 
                                   
                                 
                               
                             
                           
                         
                       
                     
                   
                   
                     
                       
                           
                         
                           
                             + 
                             
                               V 
                               0 
                             
                           
                           * 
                           t 
                           * 
                           sin 
                           ⁢ 
                              
                           
                             ( 
                             
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     In power transmission antenna  50 , N 2  element antennas  8  are arranged in N rows and N columns. The distance between element antennas  8  is L, which is the same in the vertical direction and the horizontal direction. In order to radiate power transmission radio wave  2  in a power transmission direction (ψ AZ , ψ EL ), the following variables are defined to discuss the phase shift amount given to each element antenna  8 . 
     xp: subscript in the horizontal direction (east-west direction) of element antenna  8 . 
     yp: subscript in the vertical direction (south-north direction) of element antenna  8 . 
     θ xp,yp : the direction change phase shift amount for element antenna  8  numbered (xp, yp) at the time of a power transmission direction (ψ AZ , ψ EL ). 
     k xp,yp : the phase shift amount for phase shifter  13  numbered (xp, yp) for the direction change phase shift amount θ xp,yp . 
     θ xp,yp  and k xp,yp  can be calculated by the following equations. 
       θ xp,yp =(2*π)*( L /λ)*sin(ψ EL )*(( xp−Nm )*sin(ψ AZ )+( yp−Nm )*cos(ψ AZ ))  (33)
 
         k   xp,yp =int((θ xp,yp   /θd )+0.5)  (34)
 
     The operation is described.  FIG.  8    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the first embodiment. At step S 01 , wireless power transmission device  1  radiates power transmission radio wave  2  in a power transmission direction (ψ AZ , ψ EL ). Power reception device  3  included in movable body  60  receives power transmission radio wave  2 . 
     The process of power transmission by power transmission radio wave  2  is described more specifically. Control device  10  calculates a command value of the phase and amplitude for each element module  9 . The command value of the phase and amplitude for each element module  9  is calculated such that the radiation direction of power transmission antenna  50  is directed in the power transmission direction. A power transmission control signal is the command value of the phase and amplitude for each element module. Each element module  9  generates an element transmission signal with the phase and amplitude adjusted in accordance with the power transmission control signal and radiates the element transmission signal as element radio wave  2 E p  from the corresponding element antenna  8   p . Element antenna  8   p  supplied with a transmission signal from each element module  9  radiates element radio wave  2 E p  with the phase adjusted in accordance with the power transmission direction, whereby power transmission radio wave  2  radiated in the power transmission direction is enhanced. Furthermore, adjusting the amplitude of element radio wave  2 E p  radiated by each element antenna  8   p  can make a more desirable beam form. Thus, wireless power transmission device  1  can transmit power in the power transmission direction with high efficiency. 
     At step S 02 , power transmission radio wave  2  received by power reception device  3  is converted into electric power, which is consumed, for example, as power for movable body  60  to move. The transmission and reception of electric power between wireless power transmission device  1  and movable body  60  (S 01 ) and the consumption of the received electric power in movable body  60  (S 02 ) are performed concurrently. Since the electric power transmitted by wireless power transmission device  1  at a point in time is processed with S 01  and S 02  in this order, S 02  is depicted after S 01  in the illustration of the flowchart. 
     Concurrently with S 01  and S 02 , at step S 03 , whether it is a timing for movable body  60  to send a received power value to wireless power transmission device  1 . The received power value received by movable body  60  is sent to wireless power transmission device  1 , for example, every 30 seconds. When it is not a timing to send a received power value (NO at S 03 ), the process returns to S 03 . 
     When it is a timing to send a received power value (YES at S 03 ), at step S 04 , movable body  60  sends a received power value to control device  10 , and control device  10  receives the received power value. At step S 05 , control device  10  determines whether execution of the REV method is necessary or not, from temporal transition of the received power value. When it is determined that execution of the REV method is not necessary (NO at S 05 ), the process returns to S 03 . 
     REV method necessary or unnecessary determiner  26  has a table of thresholds of received power values to the distance to movable body  60 . REV method necessary or unnecessary determiner  26  searches the table by a current distance G to movable body  60  and acquires a threshold. Then, whether the current received power value is smaller than the threshold is checked. When the current received power value becomes smaller than the threshold, REV method necessary or unnecessary determiner  26  determines that execution of the REV method is necessary. It is determined that execution of the REV method is necessary also when a predetermined time has elapsed since the previous execution of the REV method. Whether execution of the REV method is necessary or not may be determined in the movable body to which power is transmitted wirelessly. 
     When it is determined that execution of the REV method is necessary (YES at S 05 ), at step S 06 , the REV method is executed. By performing the REV method, the phase difference between element electric field vectors by element radio waves  2 E p  radiated by element antennas  8   p  is calculated, and a phase offset value for compensating for the phase difference is calculated. At step S 07 , the phase offset value obtained by the REV method is set in each phase shifter  13 . After S 07  is performed, the process returns to S 03 . 
     Concurrently with S 01  to S 02  and S 03  to S 07 , the process at steps S 11  to S 13  is performed. At S 11 , pilot transmitter  5  included in movable body  60  transmits pilot signal  4 . Pilot antenna  6  included in wireless power transmission device  1  receives pilot signal  4  and generates a pilot reception signal. At step S 12 , arrival direction detecting device  7  detects arrival direction  78  of pilot signal  4  by mono-pulse angle measurement for the pilot reception signal. At step S 13 , radiation direction determiner  33  determines a power transmission direction (ψ AZ , ψ EL ) based on arrival direction  78 . It is assumed that the power transmission direction is a direction opposite to the arrival direction. The position of movable body  60  after the elapse of a predetermined time may be predicted based on the arrival direction and the moving speed of movable body  60 , and the direction toward the predicted direction may be set as a power transmission direction. Power transmission antenna  50  radiates power transmission radio wave  2  at S 01  in the power transmission direction (ψ AZ , ψ EL ) determined at S 13 . 
     After S 13  is performed, the process returns to S 11 . The process at S 11  to S 13  is performed periodically in predetermined cycles. The length of one cycle is determined such that the difference between the arrival direction calculated last time and the current arrival direction is within an acceptable range even when movable body  60  moves at the possible maximum moving speed. 
     Since pilot signal  4  is transmitted from movable body  60  and wireless power transmission device  1  radiates power transmission radio wave  2  in the direction in which pilot signal  4  arrives, power reception device  3  included in movable body  60  can receive power transmission radio wave  2  efficiently. 
     The procedure of executing the REV method is described referring to  FIG.  9   .  FIG.  9    is a flowchart illustrating the procedure of calculating an element electric field vector of a radio wave radiated by each element antenna by the REV method in the wireless power transmission device according to the first embodiment. 
     First of all, at step S 31 , control device  10  sends data acquisition command  73  to on-board control device  19 . 
     At step S 32 , data acquisition command interpreter  63  interprets data acquisition command  73  and stores a predetermined number of pieces of measurement period data  70  specifying the time to start and end of the measurement into data storage device  21 . The pth measurement period is represented by a variable Tp. At step S 33 , p=0 is set, and REV method executor  27  sets only the direction change phase shift amount in the phase shift amount of each phase shifter  13 . The measurement period Tp is a period including one REV method unit period. In the flowchart illustrated in  FIG.  9   , all measurement periods Tp required are set in one data acquisition command  73 . At least one measurement period Tp may be set in one data acquisition command  73 . 
     At step S 34 , p=p+1 is set, and REV method executor  27  selects one phase shifter  13  in the order specified by REV method scenario  74 . The selected phase shifter  13  is denoted as phase shifter  13   p . Phase shifter  13   p  is an operating phase shifter that is part of phase shifters of which phase shift amount is changed. At step S 35 , REV method executor  27  changes the operation phase shift amount of phase shifter  13   p  in measurement period Tp based on REV method scenario  74  and records phase operation data  75 . Upon completion of a sequence of changing the operation phase shift amount of phase shifter  13   p , the phase shift amount of phase shifter  13   p  is set to be only the direction change phase shift amount. In measurement period Tp, step S 36  is performed as a process performed concurrently with S 35 . At S 36 , monitor antenna  17  receives a radio wave and measures an electric field strength Cp that is detection data  71  in measurement period Tp. 
     At step S 37 , movable body communication device  20  sends electric field strength Cp in measurement period Tp from movable body  60  to control device  10 . Electric field strength Cp is compressed by transmission data generator  64  before being sent so that the same content can be sent with a smaller data volume. The process of sending electric field strength Cp at S 37  may be performed before the process of measuring electric field strength Cp is completed at S 36 . Electric field strength Cp in measurement period Tp is electric field change data that represents change in electric field in measurement period Tp. 
     At step S 38 , communication device  30  receives electric field strength Cp. 
     At step S 39 , measurement data analyzer  35  determines time tpmax when electric field strength Cp measured in measurement period Tp takes maximum value Cpmax and time tpmin when it takes minimum value Cpmin. S 39  may be performed after all of the electric field strengths Cp in measurement period Tp are input, or time tpmax and time tpmin may be detected by element electric field calculator  29  every time electric field strength Cp is input. Time tpmax and time tpmin are the phase shift amount detection time of phase shifter  13   p  that is the operating phase shifter. Electric field strength Cp in measurement period Tp is operating phase shifter-corresponding radio wave data that is a set of detection data  71  detected for each of the operation phase shift amounts for phase shifter  13   p  in an REV method unit period. 
     At step S 40 , operation phase shift amount acquirer  36  refers to phase operation data  75  and detects the operation phase shift amount spmax of phase shifter  13   p  at time tpmax and the operation phase shift amount spmin of phase shifter  13   p  at time tpmin. 
     At step S 41 , element electric field vector calculator  37  calculates the phase and amplitude of element electric field vector Ep from the operation phase shift amount spmax and the operation phase shift amount spmin and maximum value Cpmax and minimum value Cpmin of electric field strength Cp. 
     Here, the ratio of maximum value Cpmax to minimum value Cpmin of electric field strength Cp is defined as r 2 , and the operation phase shift amount spmax or the operation phase shift amount spmin or the average value is defined as Δ 0 . Δ 0  is the operation phase shift amount. The ratio of maximum value Cpmax to minimum value Cpmin is called electric field strength change ratio. In the method indicated in PTL 2, a value k obtained by dividing the phase offset value X and the amplitude of the element electric field vector by the amplitude of the composite electric field vector can be calculated as follows. r, p, and k are consistent with the variables in PTL 2. In other sections of the present description, r, p, and k are used in a different meaning. 
         k=p /√(1+2*cos Δ 0   +p   2 )  (35)
 
         X =tan −1 (sin Δ 0 /(cos Δ 0   +p )  (36)
 
     Here, r, p, and AO are determined as follows. 
         r   2   =|Cp max|/| Cp min|  (37)
 
         p =( r− 1)/( r+ 1)  (38)
 
     Δ 0  is determined by any one of the following three equations. Any equation yields Δ 0  in a range of 0≤Δ 0 &lt;180. 
       Δ 0   =sp max−180*int( sp max/180)  (39-1)
 
       Δ 0   =sp min−180*int( sp min/180)  (39-2)
 
       Δ 0 =( sp max−180*int( sp max/180)+ sp min−180*int( sp min/180))/2  (39-3)
 
     The phase offset value X may be calculated in an abbreviated way by the following equation. The phase offset value X is calculated at least based on Δ 0 . 
         X=Δ   0   (40)
 
     At step S 42 , it is checked whether there is any phase shifter  13  not yet processed. When there exists phase shifter  13  not yet processed (YES at S 42 ), the process returns to step S 34 . 
     When there exists no phase shifter  13  not yet processed (NO at S 42 ), the process ends. 
     By executing the REV method, phase offset value  77  is calculated and set in phase shifter  13  included in each element module. The phase reference of each element module can be equalized (matched) by phase offset value  77 . 
     The effect obtained by the power transmission beam tracking movable body  60  during execution of the REV method is explained with an operation example. Td=1.00 msec is set as a parameter of the REV method. The time required for one cycle of the REV method is N*nd*Td=10*128*1.00=1280 msec. 
     The parameters for movable body  60  are G 0 =1000 m, ψ 0 =0 degrees, V 0 =−30 msec, and ξ 0 =90 degrees. This is a case where movable body  60  moves horizontally at 30 m per second in the sky 1000 m just above wireless power transmission device  1 . When ψ 0 &gt;0 degrees is satisfied, movable body  60  moves in the lifting direction. 
     It is assumed that the phase error φ p  has the following pattern 1. The unit of phase error is denoted by degrees. The phase error φ p  is a target to be calculated by the REV method. 
       (φ 1 ,φ 2 ,φ 3 ,φ 4 ,φ 5 ,φ 6 ,φ 7 ,φ 8 ,φ 9 ,φ 10 )=(−45,51,−36,39,−27,27,−18,15,−9,3)  (Pattern 1 of Phase Error)
 
       FIG.  10    illustrates the loci of the composite electric field vector Esum in wireless power transmission device  1 , in which the power transmission direction tracks a movable body during execution of the REV method in an operation example.  FIG.  11    illustrates temporal change of the amplitude |Esum| and the phase θsum of the composite electric field vector in wireless power transmission device  1  in the operation example. In  FIG.  11   , the time is expressed using a time period (128 msec) of changing the operation phase shift amount in one element module  9  as a unit. The time period in which the operation phase shift amount is changed in one element module  9  is called REV method unit period. In  FIG.  10   , the locus of the composite electric field vector in an odd-numbered REV method unit period is depicted by a solid line, and an even-numbered REV method unit period is depicted by a broken line. The starting point and the end point of the REV method and the time points of 0.25 and 0.75 in each REV method unit period are marked by rhombuses. In  FIG.  11   , the change of amplitude is depicted by a solid line, and the change of phase is depicted by a broken line. In  FIG.  11   , the amplitude |Esum0| and the phase θsum0 obtained when the REV method is not executed, that is, the phase shift amount of each phase shifter  13  is set only to be the direction change phase shift amount are also depicted by a thin solid line or broken line. The REV method unit period is the operating phase shifter-corresponding period that is a time period in which the operating phase shifter takes all of operation phase shift amounts. 
     The loci illustrated in  FIG.  10    have a portion in which the amplitude of the composite electric field vector is changed sharply because the direction change phase shift amount is changed every 10 msec. When the phase error φp is not zero, the composite electric field vector Esum in one REV method unit period has an oval shape centered on a position deviating from the real axis. The center of the locus of the composite electric field vector Esum in one REV method unit period is called unit locus center. In an REV method unit period with a positive phase error φp, the imaginary part Y of the unit locus center is positive. In an REV method unit period with a negative phase error φp, the imaginary part Y of the unit locus center is negative. As the absolute value of the phase error φp is greater, the unit locus center is farther from the real axis (the straight line with Y=0). In each REV method unit period, the position where the oval locus intersects the real axis is substantially the same position. The composite electric field vector locus is changed significantly with the phase error φp of phase shifter  13   p  serving as the operating phase shifter in each REV method unit period. In  FIG.  11   , when the REV method unit period is changed, the state of change of the amplitude |Esum| and the phase θsum is changed significantly. When the movable body is tracked, the amplitude |Esum| of the composite electric field vector has a shape in which change by the operation phase shift amount is added to a substantially constant value. 
       FIG.  12    illustrates the loci of the composite electric field vector E2sum in the wireless power transmission device when the power transmission direction does not track a movable body during execution of the REV method in a comparative example.  FIG.  13    illustrates temporal change of the amplitude |E2sum| and the phase θ2sum of the composite electric field vector in the wireless power transmission device in a comparative example. In  FIG.  13   , the amplitude |E2sum0| and the phase θ2sum0 without variation by the operation phase shift amount are also depicted by a thin solid line or broken line. In the comparative example in which the power transmission direction does not track the movable body, the amplitude |E2sum0| of the composite electric field vector without variation by the operation phase shift amount is decreased gradually, and the locus of E2sum is moved to the left side in  FIG.  12    with lapse of time. 
     As illustrated in  FIG.  13   , the amplitude |E2sum| of the composite electric field vector in the wireless power transmission device in the comparative example is increased or decreased, because the operation phase shift amount of the operating phase shifter is changed by the REV method, but is decreased gradually. The phase θ2sum of the composite electric field vector in the comparative example is increased gradually while varying. 
       FIG.  14    is an enlarged diagram of temporal changes of the amplitude |Esum| of the composite electric field vector in wireless power transmission device  1  in the operation example and the amplitude |E2sum| of the composite electric field vector in the comparative example. |Esum| and |E2sum| differ in time when they take the maximum value or the minimum value. Therefore, the wireless power transmission device  1  and the comparative example differ in element electric field vector obtained by the REV method. 
       FIG.  15    is a diagram illustrating a phase offset value and a phase error remaining after correction obtained in the wireless power transmission device according to the first embodiment and the comparative example, in the operation example.  FIG.  15 (A)  illustrates the set phase error and the phase offset value, and  FIG.  15 (B)  illustrates the remaining phase error. The setting value of the phase error is depicted by a thin solid line, the phase offset value obtained when the power transmission direction tracks the movable body during execution of the REV method is depicted by a thick solid line, and the phase offset value obtained when the power transmission direction does not track the movable body (without movement correction) is depicted by a thick broken line.  FIG.  15 (B)  illustrates the remaining phase error obtained by subtracting the phase offset value from the set phase error. In  FIG.  15   , the average value of the phase offset value for each phase shifter  13   p  and the average value of the remaining phase error are zero. 
     The phase offset value with movement correction is calculated such that the difference from the set phase error φp is approximately 5 degrees or less. In the phase offset value without movement correction, the difference between the phase offset value obtained by calculation and the set phase error φp is increased after the sixth REV method unit period. In the example illustrated in the drawing, an error of approximately −35 degrees is generated in the sixth REV method unit period, and an error of approximately +55 degrees is generated in the tenth REV method unit period. 
       FIG.  16    is a diagram comparing the absolute values of the amplitude of the composite electric field vector after correction in the wireless power transmission device according to the first embodiment and the comparative example in the operation example. When the phase of element radio wave  2 E p  radiated by each element antenna  8   p  is matched, |Esum|=10 is satisfied. In the pattern 1 of the phase error illustrated in  FIG.  15   , |Esum| is decreased to 8.6 before execution of the REV method. In the REV method with movement correction, |Esum| is 9.95 after correction. In the REV method without movement correction, |E2sum| is 9.33 after correction. It can be understood that the power transmission direction tracks the movable body during execution of the REV method whereby the phase error can be eliminated accurately by the REV method. When the power transmission direction does not track the movable body during execution of the REV method, the amplitude of the composite electric field vector recovers only to the amplitude approximately 7% smaller than the original amplitude, after execution of the REV method. When the power transmission direction does not track the movable body during execution of the REV method, the accuracy of the REV method is not sufficient and the effect of the REV method is not sufficient, either. 
     When the REV method is executed actually, the phase error φp is unknown before execution of the REV method. The difference in accuracy of the REV method with the patterns of phase error φp is described referring to  FIG.  17    to  FIG.  20   .  FIG.  17    is a diagram illustrating the patterns of phase error used to analyze the influence of the pattern of phase error in the wireless power transmission device according to the first embodiment and the comparative example.  FIG.  18    is a diagram illustrating changes of the amplitude of the electric field vector and the power value after correction to change of the moving speed of the movable body in the wireless power transmission device according to the first embodiment and the comparative example, comparing for three patterns.  FIG.  19    is a diagram illustrating the patterns of phase error used to analyze the influence of the magnitude of phase error in the wireless power transmission device according to the first embodiment and the comparative example.  FIG.  20    is a diagram illustrating changes of the amplitude of the electric field vector and the power value after correction to change of the moving speed of the movable body in the wireless power transmission device according to the first embodiment and the comparative example, comparing for the magnitudes of phase error. 
     The patterns of phase error φp illustrated in  FIG.  17    are the pattern 1 described above and two patterns described below. In  FIG.  17    to  FIG.  20   , the pattern 1 is denoted by a reference sign PT 1 , the pattern 2 is denoted by a reference sign PT 2 , and the pattern 3 is denoted by a reference sign PT 3 . In  FIG.  17   , the pattern 1 is depicted by a solid line, the pattern 2 is depicted by a broken line, and the pattern 3 is depicted by a long and short dashed line. 
       (φ 1 ,φ 2 ,φ 3 ,φ 4 ,φ 5 ,φ 6 ,φ 7 ,φ 8 ,φ 9 ,φ 10 )=(−45,51,−9,3,−36,39,−18,15,−27,27)  (Pattern 2 of Phase Error)
 
       (φ 1 ,φ 2 ,φ 3 ,φ 4 ,φ 5 ,φ 6 ,φ 7 ,φ 8 ,φ 9 ,φ 10 )=(3,−9,15,−18,27,−27,39,−36,51,−45)  (Pattern 3 of Phase Error)
 
     The conditions for the movable body are G 0 =1000 m, ψ 0 =0 degrees, and ξ 0 =90 degrees, and the moving speed V 0  of the movable body is changed in a range of 60 to −60 (m/sec). In  FIG.  18   , |Esum| and |Esum| 2  with movement correction are depicted by solid lines, and those before the REV method are depicted by broken lines. For |E2sum| and |E2sum| 2  without movement correction, the pattern 1 is depicted by a solid line, the pattern 2 is depicted by a broken line, and the pattern 3 is depicted by a long and short dashed line. |Esum| with movement correction is calculated such that |Esum|≥9.88 is satisfied in each pattern and at moving speed |V 0 |≤60. |E2sum| without movement correction is decreased when |V 0 | is large. The range in which |E2sum| is equal to or greater than |Esum| before execution of the REV method is the range of 40&gt;V 0 &gt;40 in the pattern 1, 40&gt;V 0 &gt;40 in the pattern 2, and 50&gt;V 0 &gt;50 in the pattern 3. 
     In the range of |V 0 |≤35, the difference in |E2sum| due to the difference in pattern is approximately equal to or less than 0.14. The patterns with the largest |E2sum| and the patterns with the smallest |E2sum| change with the value of V 0 . In the range of |V 0 |≥40, the difference in |E2sum| due to the difference in pattern increase and the difference at most 1 is generated depending on the patterns. In the range of |V 0 |≥40, the patterns with the largest |E2sum| and the patterns with the smallest |E2sum| change. 
     The influence of the magnitude of phase error φp in the same pattern is illustrated in  FIG.  19    and  FIG.  20   . A pattern in which the amplitude in the pattern 2 is set to ⅔ is called pattern 4, and a pattern in which the amplitude in the pattern 2 is set to ⅓ is called pattern 5. In  FIG.  19    and  FIG.  20   , the pattern 4 is denoted by a reference sign PT 4 , and the pattern 5 is denoted by a reference sign PT 5 . In  FIG.  19   , the pattern 2 is depicted by a solid line, the pattern 4 is depicted by a broken line, and the pattern 5 is depicted by a long and short dashed line. In  FIG.  20   , |Esum| and |Esum| 2  before execution of the REV method for the pattern 2, the pattern 4, and the pattern 5 are depicted by broken lines. 
       (φ 1 ,φ 2 ,φ 3 ,φ 4 ,φ 5 ,φ 6 ,φ 7 ,φ 8 ,φ 9 ,φ 10 )=(−30,34,−6,2,−24,26,−12,10,−18,18)  (Pattern 4 of Phase Error)
 
       (φ 1 ,φ 2 ,φ 3 ,φ 4 ,φ 5 ,φ 6 ,φ 7 ,φ 8 ,φ 9 ,φ 10 )=(−15,17,−3,1,−12,13,−6,5,−9,9)  (Pattern 5 of Phase Error)
 
     In  FIG.  20   , |Esum| with movement correction can be calculated such that |Esum|≥9.92 is satisfied in each pattern and the moving speed |V 0 |≤60. The difference between patterns of |E2sum| without movement correction is approximately 0.19 or less in a range where V 0 ≤30 is satisfied. In a range where V 0 ≥30 is satisfied, the difference between patterns is increased and the magnitude of difference varies. In the case without movement correction, the correction accuracy of phase error is not good not depending on the magnitude of phase error φp. When the moving speed |V 0 | is large, execution of the REV method makes the power transmission efficiency lower than before the REV method, in the case without movement correction. 
     Referring to  FIG.  21   , the influence of the presence direction of the movable body, that is, the power transmission direction ψ 0  at the start of the REV method is studied.  FIG.  21    is a diagram illustrating changes of the amplitude of the electric field vector and the power value after correction to change of the moving speed of the movable body in the wireless power transmission device according to the first embodiment and the comparative example, comparing for the directions in which the movable body is present at the start of the REV method. In  FIG.  21   , the phase error φp is the pattern 3, and G 0  is 1000 m. The moving direction ξ 0  of the movable body is orthogonal to the power transmission direction ψ 0 . The moving speed V 0  is changed in a range of 60 to −60 (m/sec) in the following three cases. 
     Case 1: (ψ 0 , ξ 0 )=(0 degrees, 90 degrees) 
     Case 2: (ψ 0 , ξ 0 )=(15 degrees, 105 degrees) 
     Case 3: (ψ 0 , ξ 0 )=(30 degrees, 120 degrees) 
     In  FIG.  21   , Case 1 is indicated by ψ 0 =0 degrees, Case 2 is indicated by ψ 0 =15 degrees, and Case 3 is indicated by ψ 0 =30 degrees. In  FIG.  21   , |Esum| and |Esum| 2  with movement correction are indicated by solid lines, and those before the REV method are indicated by broken lines. For |E2sum| and |E2sum| 2  without movement correction, the graph satisfying ψ 0 =0 degrees is depicted by a solid line, the graph satisfying ψ 0 =15 degrees is depicted by a broken line, and the graph satisfying ψ 0 =30 degrees is indicated by a long and short dashed line. 
     In  FIG.  21   , |Esum| with movement correction can be calculated such that |Esum|≥9.94 is satisfied in each angle of the power transmission direction ψ 0  of the movable body and the moving speed |V 0 |≤60. |E2sum| without movement correction is greater when ψ 0 =30 degrees is satisfied than when ψ 0 =0 degrees is satisfied and when ψ 0 =15 degrees is satisfied in the whole speed range. At V 0 =−35 degrees and V 0 =−40 degrees, |E2sum| when ψ 0 =15 degrees is satisfied is smaller than |E2sum| when ψ 0 =0 degrees is satisfied. At the other speeds, |E2sum| when ψ 0 =15 degrees is satisfied is greater than |E2sum| when ψ 0 =0 degrees is satisfied. It can be thought that the amount of decrease of |E2sum| without phase correction compared with |Esum| is greater as |ψ 0 | is smaller. The effect obtained by the power transmission beam tracking the movable body during execution of the REV method is greater as |ψ 0 | is smaller. 
     Referring to  FIG.  22   , the influence of the angle difference between the power transmission direction ψ 0  to the movable body and the moving direction of the movable body at the start of the REV method is studied.  FIG.  22    is a diagram illustrating changes of the amplitude of the electric field vector and the power value after correction to change of the moving speed of the movable body in the wireless power transmission device according to the first embodiment and the comparative example, comparing for the angle differences between the direction in which the movable body is present at the start of the REV method and the moving direction of the movable body. In  FIG.  22   , the phase error φp is the pattern 3, G 0 =1000 m, and ψ 0 =0 degrees. The moving speed V 0  is changed in a range from 60 to −60 (m/sec) with three moving directions ξ 0  of movable body: ξ 0 =90 degrees, ξ 0 =75 degrees, and ξ 0 =60 degrees. In  FIG.  22   , |Esum| and |Esum| 2  with movement correction are depicted by solid lines, and those before the REV method are depicted by broken lines. For |E2sum| and |E2sum| 2  without movement correction, the graph satisfying ξ 0 =90 degrees is depicted by a solid line, the graph satisfying ξ 0 =75 degrees is depicted by a broken line, and the graph satisfying ξ 0 =60 degrees is depicted by a long and short dashed line. 
     In  FIG.  22   , |Esum| with movement correction can be calculated such that |Esum|≥9.94 is satisfied in each angle of moving direction ξ 0  and the moving speed |V 0 |≤60. |E2sum| without movement correction is substantially the same when ξ 0 =90 degrees is satisfied and when ξ 0 =75 degrees is satisfied, in V0≤15 is satisfied. The difference is approximately 0.07 or less. When ξ 0 =60 degrees is satisfied, it is greater than when ξ 0 =90 degrees is satisfied and when ξ 0 =75 degrees is satisfied, except when V 0 =60 is satisfied. 
     As illustrated in  FIG.  18    and  FIG.  20    to  FIG.  22   , the power transmission beam tracks the movable body during execution of the REV method, whereby the phase reference of each phase shifter  13   p  can be equalized by the REV method, not depending on the pattern of phase error φp, the power transmission direction ψ 0  to the movable body at the start of the REV method, the moving direction ξ 0  of the movable body, and the speed V 0  of the movable body. As a result, the amplitude |Esum| of the composite electric field vector obtained by executing the REV method can be set to be the theoretically possible largest value. 
     The power transmission direction of power transmission radio wave  2  is controlled such that it is directed in the direction of movable body  60  during execution of the REV method. Thus, the REV method can be executed accurately and power transmission radio wave  2  can be radiated accurately in the radiation direction during power transmission to the movable body. Further, since time data  72  is included in detection data  71  used in executing the REV method, the correspondence between the phase shift amount and the detection data  71  can be determined by the time data correctly, enabling the REV method to be executed accurately. 
     The power transmission direction of power transmission radio wave  2  is controlled such that it is pointed in the direction of movable body  60  during execution of the REV method. By doing so, the following effects can be expected. 
     (1) The influence on the reception strength during execution of the REV method due to a deviation of the power transmission direction from movable body  60  is reduced, and the accuracy of the REV method executed for the moving movable body is improved. The power transmission beam formed after execution of the REV method attains a more ideal form, thereby improving the power transmission efficiency. 
     (2) With improvement in accuracy of the result of the REV method, a beam closer to an ideal beam is formed, and radiation of a power transmission radio wave in an unnecessary direction is avoided. As a result, the influence of interference with others is reduced. 
     (3) Since the power transmission efficiency after execution of the REV method is increased, the period until the received power strength is decreased to such a degree that execution of REV method is necessary next time can be prolonged. With a longer interval of execution of the REV method, the proportion of the period for executing the REV method to the whole period in which power transmission is required to be performed is reduced. The power transmission efficiency is decreased during execution of the REV method. With a lower proportion of the period for executing the REV method to the whole period in which power transmission is required to be performed, the power transmission efficiency is improved. 
     The simulation results are described assuming that the distance from the wireless power transmission device to the power reception device is a distance at which a far field is established. Even when the distance is shorter than a distance at which a far field is established (near field), the power transmission direction of power transmission radio wave  2  is controlled to be directed in the direction of movable body  60  during execution of the REV method, whereby the accuracy of the REV method is improved compared with when the power transmission direction of power transmission radio wave  2  is not changed during execution of the REV method. When the distance from the wireless power transmission device to the power reception device is a distance at which a near field is established, the calculation of the phase difference of element radio wave  2 E p  radiated by each element antenna  8  that is received by the power reception device and the calculation in the REV method are done by calculation formulae for a near field. 
     Pilot signal  4  may be pulse-modulated so that detection data  71  is sent from movable body  60  by pilot signal  4 . The communication between movable body  60  and control device  10  may be in any form that enables communication at a required speed. 
     Since pilot signal  4  is transmitted from movable body  60  and wireless power transmission device  1  radiates power transmission radio wave  2  in the direction in which pilot signal  4  arrives, power reception device  3  included in movable body  60  can receive power transmission radio wave  2  efficiently. 
     Electric field change data generated based on detection data  71  may be sent as electric field change data from on-board control device  19 , instead of sending detection data  71  during execution of the REV method. By doing so, the data volume sent from the on-board control device to the wireless power transmission device can be reduced. The on-board control device may be equipped with an element electric field calculator to calculate the element electric field vector in the on-board control device. Detection data  71  itself is also included in the electric field change data generated based on detection data  71 . 
     The power transmission antenna may have a mechanism that changes the radiation direction by mechanical driving. By combining mechanical driving with changing the radiation direction electrically to change the radiation direction, power can be transmitted to the movable body even when the movable body moves more largely. 
     The element module is provided for each element antenna, but one element module may be provided every two or more element antennas. The element module may be provided every predetermined number of element antennas. 
     These are applicable to the other embodiments. 
     Second Embodiment 
     In a wireless power transmission device according to a second embodiment, the power transmission antenna has a plurality of power transmission antenna units.  FIG.  23    is a diagram illustrating an overall configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to the second embodiment. A wireless power transmission device  1 A includes a power transmission antenna  50 A. Power transmission antenna  50 A includes four power transmission antenna units  51 . Four power transmission antenna units  51  are arranged in two rows and two columns close to each other. Four power transmission antenna units  51  constitute one power transmission antenna  50 A. The power transmission antenna may be configured with two, three, or five or more power transmission antenna units. 
     Power transmission antenna units  51  each include two kinds of element modules  9 , namely, a first-stage element module  9 P and a second-stage element module  9 S. Power transmission antenna unit  51  includes one transmission signal generator  11 , one first-stage element module  9 P, one distribution circuit  12 , and second-stage element modules  9 S as many as element antennas  8 . First-stage element module  9 P and second-stage element modules  9 S have the same structure and each includes phase shifter  13  and amplifier  14 . A transmission signal outputted by transmission signal generator  11  is inputted to first-stage element module  9 P. A transmission signal outputted by first-stage element module  9 P is distributed by distribution circuit  12  and inputted to each second-stage element module  9 S. A transmission signal outputted by each second-stage element module  9 S is inputted to the corresponding one element antenna  8 . 
     A control device  10 A is also modified so that power is transmitted by power transmission antenna  50 A having first-stage element modules  9 P and second-stage element modules  9 S and the REV method is executed.  FIG.  24    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the second embodiment. In control device  10 A, an REV method executor  27 A, a data storage  25 A, and a radio wave radiation controller  34 A are modified. REV method executor  27 A executes the REV method in two stages: the REV method for second-stage element modules  9 S and the REV method for first-stage element modules  9 P. REV method scenario  74 A enables execution of the REV method for second-stage element modules  9 S and the REV method for first-stage element modules  9 P. Data storage  25 A stores REV method scenario  74 A. Radio wave radiation controller  34 A set the phase shift amount for radiating power transmission radio wave  2  in the power transmission direction separately for first-stage element modules  9 P and second-stage element modules  9 S. 
     The operation is described.  FIG.  25    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the second embodiment. In  FIG.  25   , points different from  FIG.  8    in the first embodiment are described. 
     When it is determined that execution of the REV method is necessary (YES at S 05 ), at step S 06 A, the REV method is executed for second-stage element module  9 S. By executing the REV method, the phase difference between element electric field vectors by element radio waves  2 E p  radiated by element antennas  8   p  is calculated, and a phase offset value of second-stage element module  9 S for compensating for the phase difference is calculated. At step S 07 A, the phase offset value obtained by the REV method is set in phase shifter  13  included in each second-stage element module  9 S. At step S 08 , the REV method is executed for first-stage element module  9 P. By executing the REV method, the phase difference between electric field vectors by radio waves radiated by power transmission antenna units  51  is calculated, and a phase offset value of first-stage element module  9 P for compensating for the phase difference is calculated. At step S 09 , the phase offset value obtained by the REV method is set in phase shifter  13  included in each first-stage element module  9 P. After S 09  is performed, the process returns to S 03 . 
     The procedure of executing the REV method at S 06 A and S 08  is similar to that in  FIG.  9    in the first embodiment. 
     Wireless power transmission device  1 A operates similarly to wireless power transmission device  1  and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. 
     Third Embodiment 
     In a third embodiment, the first embodiment is modified such that the power transmission antenna is moved mechanically so that the power transmission direction can be changed.  FIG.  26    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to the third embodiment. In  FIG.  26   , points different from  FIG.  1    in the first embodiment are described. A power transmission antenna  50 B is installed on an azimuth rotating mount  52  capable of changing the azimuth angle such that its opening area is inclined. Power transmission antenna  50 B is installed on azimuth rotating mount  52  such that the opening area forms an angle of 30 degrees, for example, relative to the horizontal plane. In  FIG.  26   , arrival direction detecting device  7  and control device  10 B are also installed on azimuth rotating mount  52 . Arrival direction detecting device  7  and control device  10 B are not necessarily installed on azimuth rotating mount  52 . 
       FIG.  27    is a diagram illustrating an overall configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to the third embodiment. In  FIG.  27   , points different from  FIG.  2    in the first embodiment are described. A wireless power transmission device  1 B includes azimuth rotating mount  52 . Azimuth rotating mount  52  can rotate around the vertical azimuth rotation axis. Azimuth rotating mount  52  can rotate infinitely clockwise and counterclockwise. Power transmission antenna  50 B (including pilot antenna  6 ) is installed on azimuth rotating mount  52 . When azimuth rotating mount  52  rotates, power transmission antenna  50 B and pilot antenna  6  rotate in the same way. Control device  10 B also controls azimuth rotating mount  52 . Pilot antenna  6  may be installed separately from power transmission antenna  50 B. 
     Azimuth rotating mount  52  is a power transmission antenna driving device that moves power transmission antenna  50 B mechanically to change the radiation direction. Azimuth rotating mount  52  supports power transmission antenna  50 B such that power transmission antenna  50 B is inclined relative to a reference plane, where the horizontal plane is the reference plane. Azimuth rotating mount  52  rotates power transmission antenna  50 B around the azimuth rotation axis that is the rotation axis vertical to the reference plane. 
       FIG.  28    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the third embodiment. In  FIG.  28   , points different from  FIG.  5    in the first embodiment are described. Control device  10 B also includes a mount controller  38  to control azimuth rotating mount  52 . A radiation direction determiner  33 B is modified. 
     The following variables are defined for explaining the operation of radiation direction determiner  33 B and mount controller  38 . 
     ψ AZM : the azimuth angle in which azimuth rotating mount  52  is directed. 
     ψ AZE : the azimuth angle component of the power transmission direction relative to the front direction of power transmission antenna  50 B. 
       ψ AZE =ψ AZ −ψ AZM   (41)
 
     ψ ELM : the inclination angle of azimuth rotating mount  52 . The angle between the horizontal plane and the opening area of power transmission antenna  50 B. Here, ψ ELM =30 degrees. 
     ψ ELE : the altitude angle of the power transmission direction relative to the front direction of power transmission antenna  50 B. The altitude angle is the angle between the power transmission direction and the direction toward the zenith. 
       ψ ELE =ψ EL −ψ ELM   (42)
 
     ψ AZmax : the upper limit value for |ψ AZE |. For example, 45 degrees. 
     ψ ELmax : the upper limit value for the altitude angle ψ ELE . For example, 45 degrees. 
     ψ ELmin : the lower limit value for the altitude angle γ ELE . For example, −45 degrees. 
     In wireless power transmission device  1 B, pilot antenna  6  and arrival direction detecting device  7  detect the arrival direction with respect to the direction of the opening area of power transmission antenna SOB. Arrival direction detecting device  7  detects the arrival direction (ψ AZE , ψ ELE ). Thus, the direction toward the arrival direction (ψ AZE , ψ ELE ) is set as the radiation direction (ψ AZE , ψ ELE ) of power transmission radio wave  2 . When the presence direction (ψ AZ , ψ EL ) of the movable body is detected without using a pilot signal, the presence direction (ψ AZ , ψ EL ) is converted into the direction (ψ AZE , ψ ELE ) by equation (41) and equation (42). The direction toward the direction (ψ AZE , ψ ELE ) is set as the radiation direction of power transmission radio wave  2 . 
     Mount controller  38  controls the direction ψ AZM  in which azimuth rotating mount  52  is directed such that ψ AZE  and WELL satisfy all of the following equation (43) and equation (44). The range of the power transmission direction (ψ AZE , ψ ELE ) that satisfies all of equation (43) and equation (44) is called proper angle range. 
       |ψ AZE |≤ψ AZmax   (43)
 
       ψ ELmin ≤φ ELE ≤ψ ELmax   (44)
 
     Equation (41) is substituted into equation (43) as follows. 
       |ψ AZ −φ AZM |≤ψ AZmax   (45)
 
     Equation (42) is substituted into equation (44) as follows. 
       ψ ELmin +ψ ELM ≤ψ EL ≤ψ ELmax +ψ ELM   (46)
 
     The power transmission direction (ψ AZ , ψ EL ) may be monitored to determine whether equation (45) and equation (46) are satisfied, instead of monitoring the power transmission direction (ψ AZE , ψ ELE ). 
     There are some possible methods for mount controller  38  to control azimuth rotating mount  52 . Here, the azimuth angle of azimuth rotating mount  52  is changed only when the power transmission direction (ψ AZE , ψ ELE ) gets out of the proper angle range. The radiation direction can be changed faster by changing the power transmission direction (ψ AZE , ψ ELE ) electrically than by rotating azimuth rotating mount  52 . Azimuth rotating mount  52  may be rotated slowly such that ψ AZE  approaches zero after ψ AZE  significantly varies. 
     Mount controller  38  monitors ψ AZE  and ψ ELE  and checks whether equation (43) and equation (44) are satisfied. When equation (43) is not satisfied, azimuth rotating mount  52  is rotated so that equation (43) is satisfied. When ψ AZE &lt;−ψ AZmax  is satisfied, azimuth rotating mount  52  is rotated counterclockwise. When war ψ AZE &gt;ψ AZmax  is satisfied, azimuth rotating mount  52  is rotated clockwise. Azimuth rotating mount  52  is rotated until ψ AZE =0 degrees. During rotation of azimuth rotating mount  52 , ψ AZE  and ψ ELE  are controlled such that the power transmission direction is directed to the presence direction of movable body  60 . 
     When ψ ELE &gt;ψ ELmax  is satisfied, that is, equation (44) is not satisfied, it means that movable body  60  is at a low elevation angle (the altitude angle ψ EL  is large). The only way to satisfy equation (44) is that movable body  60  moves to a position at a higher elevation angle. When satisfying ψ ELE &gt;ψ ELmax  is detected, power transmission to movable body  60  is stopped. When satisfying ψ ELE ≤ψ ELmax  is detected, power transmission to movable body  60  is resumed. 
     When ψ ELE &lt;ψ ELmin  is satisfied, that is, equation (44) is not satisfied, azimuth rotating mount  52  is rotated. When azimuth rotating mount  52  rotates 180 degrees, ψ EL &lt;0 is changed to −ψ EL &gt;0 and ψ ELE =−ψ EL −ψ ELM &gt;ψ ELM &gt;ψ ELmin  are satisfied, then equation (44) is satisfied. 
     When mount controller  38  detects ψ ELE &lt;ψ ELmin  is satisfied, azimuth rotating mount  52  is rotated so that ψ AZE =0, ψ ELE &gt;ψ ELmin  are satisfied. The rotation direction of azimuth rotating mount  52  is determined such that the rotation angle of azimuth rotating mount  52  to satisfy ψ AZE =0, ψ ELF ≥ψ ELmin  is small. When ψ AZE ≥0 is satisfied, azimuth rotating mount  52  is rotated counterclockwise. When ψ AZE &lt;0 is satisfied, azimuth rotating mount  52  is rotated clockwise. There is a period in which |ψ AZE |&gt;ψ AZmax  is satisfied before ψ AZE =0, ψ ELE ≥ψ ELmin  are satisfied. In a period in which |ψ AZE |&gt;ψ AZmax  is satisfied, radiation of power transmission radio wave  2  is stopped and azimuth rotating mount  52  is rotated at highest speed. Rotating azimuth rotating mount  52  at highest speed can minimize the period in which radiation of power transmission radio wave  2  is stopped. While |ψ AZE |≤ψ AZmax  is satisfied, ψ AZE  and ψ ELE  are controlled such that the power transmission direction is directed to the presence direction of movable body  60 . 
     Power transmission antenna  50 B can form a power transmission beam with a smaller half-width smaller than power transmission antenna  50  at a low elevation angle.  FIG.  29    is a graph illustrating change of an amplitude attenuation ratio γ to change of deviation angle δ in the phased array antenna included in the wireless power transmission device according to the third embodiment.  FIG.  29    illustrates graphs representing change of amplitude attenuation ratio γ to change of deviation angle δ when ψ AZE =0 degrees is satisfied and either ψ EL =0 degrees, 30 degrees, or 60 degrees is satisfied. The graph satisfying ψ EL =0 degrees is depicted by a solid line, the graph satisfying ψ EL =30 degrees is depicted by a broken line, and the graph satisfying ψ=60 degrees is depicted by a long and short dashed line. When ψ EL =0 degrees is satisfied, the half-width is approximately 8.0 degrees. When ψ EL =30 degrees is satisfied, the half-width is approximately 6.8 degrees. When ψ EL =60 degrees is satisfied, the half-width is approximately 8.0 degrees. Compared with  FIG.  6   , the half-width when ψ EL =60 degrees is smaller. 
     The operation is described.  FIG.  30    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the third embodiment. In  FIG.  30   , points different from  FIG.  8    in the first embodiment are described. Steps S 14  to S 16  are added after S 13  in which the power transmission direction (ψ AZ , ψ EL ) is determined. At S 14 , the power transmission direction (ψ AZE , ψ ELE ) of power transmission antenna  50 B is determined from power transmission direction (ψ AZ , ψ EL ). The power transmission direction (ψ AZ , ψ EL ) and the power transmission direction (ψ AZE , ψ ELE ) have the relation of equation (41) and equation (42). 
     At step S 15 , it is checked whether the power transmission direction (ψ AZE , ψ ELE ) of power transmission antenna  50 B is within the proper angle range. When it is within the proper angle range (YES at S 15 ), the process returns to S 11 . When it is not within the proper angle range (NO at S 15 ), at step S 16 , azimuth rotating mount  52  is rotated such that the power transmission direction (ψ AZE , ψ ELE ) becomes within the proper angle range. After S 16  is performed, the process returns to S 11 . 
     The procedure of restoring the power transmission direction (ψ AZE , ψ ELE ) out of the proper angle range to the proper angle range at S 16  is described referring to  FIG.  31   . At step S 61 , it is checked whether ψ ELE &gt;ψ ELmax  is satisfied or not. When ψ ELE &gt;ψ ELmax  is satisfied (YES at S 61 ), at step S 62 , radiation of power transmission radio wave  2  is stopped. At step S 63 , it is checked whether ψ ELE &lt;ψ ELmax  is satisfied or not. When ψ ELE ≤ψ ELmax  is satisfied (YES at S 63 ), at step S 64 , radiation of power transmission radio wave  2  is resumed. After S 64  is performed, the process ends. When not ψ ELE ≤ψ ELmax  is satisfied (NO at S 63 ), S 63  is performed repeatedly in predetermined cycles. 
     When ψ ELE &gt;ψ ELmax  is not satisfied (NO at S 61 ), at step S 65 , it is checked whether ψ ELE &lt;ψ ELmin  is satisfied or not. When ψ ELE &lt;ψ ELmin  (YES at S 65 ) is satisfied, at step S 66 , the rotation direction of azimuth rotating mount  62  is determined. when ψ AZE ≥0 is satisfied, the rotation direction is determined to be counterclockwise, and when ψ AZE &lt;0 is satisfied, it is determined to be clockwise. At step S 67 , azimuth rotating mount  62  is rotated. At step S 68 , it is checked whether |ψ AZE |≤ψ AZmax  is satisfied or not. When |ψ AZE |≤ψ AZmax  is satisfied (YES at S 68 ), at step S 69 , ψ AZE  and ψ ELE  are controlled such that the power transmission direction is directed to the presence direction of movable body  60 . After S 69  is performed, the process returns to S 68 . 
     When |ψ AZE |≤ψ AZmax  is not satisfied (NO at S 68 ), at step S 70 , radiation of power transmission radio wave  2  is stopped and the rotation speed of azimuth rotating mount  62  is set to the maximum. At step S 71 , it is checked whether |ψ AZE |≤ψ AZmax . When |ψ AZE |≤ψ AZmax  is satisfied (YES at S 71 ), at step S 72 , radiation of power transmission radio wave  2  is resumed and the rotation speed of azimuth rotating mount  62  is set to a normal speed. At step S 73 , ψ AZE  and ψ ELE  are controlled such that the power transmission direction is directed to the presence direction of movable body  60 . At step S 74 , it is checked whether ψ AZE =0 degrees. When ψ AZE =0 degrees is not satisfied (YES at S 74 ), S 74  is performed repeatedly in predetermined cycles. When ψ AZE =0 degrees is satisfied (YES at S 74 ), at step S 75 , the rotation of azimuth rotating mount  62  is stopped. After S 75  is performed, the process ends. 
     When ψ ELE &lt;ψ ELmin  (NO at S 65 ) is not satisfied, at step S 76 , it is checked whether |ψ AZE |&gt;ψ AZmax  is satisfied or not. When |ψ AZE |&gt;ψ AZmax  is not satisfied (NO at S 76 ), the process ends. When |ψ AZE &gt;ψ AZmax  is satisfied (YES at S 76 ), at step S 77 , the rotation direction of azimuth rotating mount  62  is determined. When ψ AZE ≥0 is satisfied, the rotation direction is determined to be counterclockwise, and when ψ AZE &lt;0 is satisfied, it is determined to be clockwise. At step S 78 , azimuth rotating mount  62  is rotated. At step S 79 , it is checked whether |ψ AZE |≤ψ AZmax . When |ψ AZE |≤ψ AZmax  is not satisfied (NO at S 79 ), S 79  is performed repeatedly in predetermined cycles. When |ψ AZE |≤ψ AZmax  is satisfied (YES at S 79 ), the process proceeds to S 73 . 
     In wireless power transmission device  1 B, the azimuth angle of power transmission antenna  50 B can be changed by azimuth rotating mount  52  and power transmission antenna  50 B is installed such that it is inclined relative to the horizontal plane. Thus, wireless power transmission device  1 B can transmit power to movable body  60  in a wider range of azimuth angle and elevation angle than wireless power transmission device  1 . Wireless power transmission device  1 B can form a power transmission beam with a narrower half-width than wireless power transmission device  1  at a low elevation angle. 
     The elevation angle of the direction in which the opening area of the power transmission antenna is directed may be changeable mechanically. The power transmission antenna can change the radiation direction by mechanically and electrically changing the radiation direction in combination. 
     Fourth Embodiment 
     In the first embodiment, mono-pulse tracking of a pilot signal transmitted by the receiving side on the power transmitting side is used as means for tracking a movable body. In a fourth embodiment, the pilot signal is tracked by step track method. In step track method, the orientation direction of the pilot antenna receiving a pilot signal is searched for while being changed by trial and error, and the power transmission direction of the power transmission radio wave is changed to the direction in which the reception strength of the pilot signal is increased. Although the orientation direction of the pilot antenna is also changed to the direction in which the reception strength is decreased, the power transmission direction of the power transmission radio wave tracks only the direction in which the reception strength is increased. 
     Referring to  FIG.  32    and  FIG.  33   , the structure of a wireless power transmission device  1 C and movable body  60  is described.  FIG.  32    is a diagram illustrating an overall configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to a fourth embodiment. In  FIG.  32   , points different from  FIG.  2    in the first embodiment are described. An arrival direction detecting device  7 C and a control device  10 C are modified. Arrival direction detecting device  7 C includes a signal strength meter  39  instead of pilot receiver  24 . Signal strength meter  39  measures the signal strength of a pilot reception signal. A pilot antenna controller  23 C is modified. Pilot antenna controller  23 C controls pilot antenna mount  22  by step track method 
       FIG.  33    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the fourth embodiment. In  FIG.  33   , points different from  FIG.  5    in the first embodiment are described. Control device  10 C sends a data acquisition command  73 C for each one period in which phase shifter  13  specified by REV method scenario  74 C takes the specified phase shift amount, and acquires one piece of detection data  71 C. Data storage  25 C stores REV method scenario  74 C. 
     The signal strength of the pilot reception signal measured by signal strength meter  39  is called pilot signal strength. Pilot antenna controller  23 C changes the orientation direction of pilot antenna  6  by a predetermined angle temporarily in a plurality of directions, using the orientation direction of pilot antenna  6  in the previous cycle as a reference direction. Signal strength meter  39  measures the pilot signal strength in a state in which the orientation direction of pilot antenna  6  is directed in the direction changed from the reference direction. Pilot antenna controller  23 C sets the direction in which the pilot signal strength is largest among the directions changed temporarily, as a new reference direction of the orientation direction of pilot antenna  6 . Pilot antenna controller  23 C repeats such a process to change the reference direction of the orientation direction of pilot antenna  6 . Pilot antenna controller  23 C notifies control device  10 C of the reference direction of the orientation direction of pilot antenna  6  as the arrival direction. In arrival direction detecting device  7 C, the cycle of detecting the arrival direction is longer than in arrival direction detecting device  7 . 
     In control device  10 C, a data acquisition command generator  28 C and a radiation direction determiner  33 C are modified. Radiation direction determiner  33 C updates radiation direction data  81 C in a cycle shorter than the cycle in which arrival direction data  79  is updated. Radiation direction determiner  33 C interpolates the points of time without arrival direction data  79  to generate radiation direction data  81 C. Specifically, radiation direction determiner  33 C estimates the rate of change of arrival direction data  79  and estimates arrival direction data  79  based on the estimated rate to update radiation direction data  81 C. 
     Data acquisition command  73 C is generated for each one measurement period Tp r , r=1, . . . nd in which phase shifter  13   p  specified by REV method scenario  74 C takes the specified operation phase shift amount (r*θd). 
     One piece of measurement period data  70 C is data indicating the start time and the end time of measurement period Tp r , r=1, . . . , nd. Every time data acquisition command  73 C is received, one piece of measurement period data  70 C is set. Data command generator  28 C of control device  10 C generates data acquisition command  73 C every measurement period Tp r . On-board control device  19 C generates detection data  71  by calculating the average of electric field strength in the measurement period specified by data acquisition command  73 C. On-board control device  19 C sends detection data  71  in each measurement period Tp r  to control device  10 C. Measurement period Tp r  is a period in which phase shifter  13   p  that is the operating phase shifter takes one operation phase shift amount. 
     The operation is described.  FIG.  34    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the fourth embodiment. In  FIG.  34   , points different from  FIG.  8    in the first embodiment are described. Steps S 06 C, S 12 C, and S 13 C are modified. 
     At S 06 C, data acquisition command  73 C and detection data  71  are sent and received for each one measurement period Tp r , r=1, . . . , nd, and the REV method is executed. At S 12 C, arrival direction detecting device  7 C tracks pilot signal  4  by step track method to determine the arrival direction of pilot signal  4 . At S 13 C, the rate of change of arrival direction data  79  of pilot signal  4  is estimated, and radiation direction data  81 C is estimated and updated in a cycle shorter than the updating cycle of arrival direction data  79 . 
     The procedure of executing the REV method in the fourth embodiment is described referring to  FIG.  35   . In  FIG.  35   , points different from  FIG.  9    in the first embodiment are described. S 31  and S 32  are removed, and at step S 33 , p=0 is set, and REV method executor  27  sets the phase shift amount of each phase shifter  13  only to the direction change phase shift amount. At S 34 C, p=p+1, r=0, and one phase shifter  13   p  is selected in the order specified by the REV method scenario. Subsequently to S 34 C, at step S 43 , r=r+1 is set. At step S 44 , control device  10 C sends data acquisition command  73 C to on-board control device  19 C every measurement period Tp r . At step S 45 , data acquisition command interpreter  63 C interprets data acquisition command  73 C and stores one piece of measurement period data  70 C specifying the time to start and end the measurement of the reception electric field strength into data storage device  21 C in association with Tp r . 
     Subsequently to S 45 , at step S 35 C, REV method executor  27 C causes phase shifter  13   p  to take operation phase shift amount sp r  in measurement period Tp r  based on REV method scenario  74 C and records phase operation data  75 . Concurrently with S 35 C, at step S 36 C, monitor antenna  17  receives a radio wave and measures electric field strength Cp r  that is detection data  71  in measurement period Tp r . The average value of electric field strength Cp r  in measurement period Tp r  is calculated. 
     At step S 37 C, movable body communication device  20  sends the average value of electric field strength Cp r  in measurement period Tp r  from movable body  60  to control device  10 C. Electric field strength Cp r  in measurement period Tp r  is electric field change data that represents change of electric field in measurement period Tp r . At step S 38 C, communication device  30  receives electric field strength Cp r . 
     Subsequently to S 38 C, at step S 46 , whether r=nd is satisfied or not is checked. When r=nd is satisfied, it means that all of operation phase shift amounts sp r  are taken by one phase shifter  13 . When r=nd is satisfied (YES at S 46 ), the process proceeds to S 39 . When r=nd is not satisfied (NO at S 46 ), the process returns to S 43 . 
     Wireless power transmission device  1 C operates similarly to wireless power transmission device  1  and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. Since signal strength meter  39  that outputs the reception signal strength is used, the configuration of the arrival direction detecting device is simplified. This leads to size reduction of the arrival direction detecting device. 
     Fifth Embodiment 
     In a fifth embodiment, the movable body tracking method is changed from that of the fourth embodiment. In the fourth embodiment, a pilot signal transmitted by the receiving side is tracked by step track method on the power transmitting side, as means for tracking a movable body. In the fifth embodiment, the orientation direction of the pilot antenna is changed in the neighborhood of the arrival direction of the pilot signal and the received power strength is measured. An error in the arrival direction is estimated from the orientation direction changed intentionally and the change in received power strength, and the most probable arrival direction is estimated from the estimated error. The tracking method in the fifth embodiment is called neighborhood search tracking. Control device  10 C is notified of the most probable arrival direction. Control device  10 C is similar to that in the fourth embodiment. 
       FIG.  36    is a diagram illustrating an overall configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to the fifth embodiment. In  FIG.  36   , points different from  FIG.  32    in the fourth embodiment are described. In an arrival direction detecting device  7 D, a pilot antenna controller  23 D is modified. Pilot antenna controller  23 D changes the orientation direction of pilot antenna  26  such that neighborhood search tracking is performed. 
     The operation is described.  FIG.  37    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the fifth embodiment. In  FIG.  37   , points different from  FIG.  34    in the fourth embodiment are described. At step S 12 D, arrival direction detecting device  7 D detects the arrival direction of pilot signal  4  by neighborhood search tracking. 
     Wireless power transmission device  1 D operates similarly to wireless power transmission device  1  and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. Also in the fifth embodiment, the configuration of the arrival direction detecting device can be simplified, leading to size reduction of the arrival direction detecting device. 
     Sixth Embodiment 
     In a sixth embodiment, the movable body measures its position and attitude and notifies the wireless power transmission device, and the wireless power transmission device determines the power transmission direction based on the position and the attitude of the movable body. The sixth embodiment is a modification to the first embodiment. The modification may be made based on the second to fifth and other embodiments. 
     Referring to  FIG.  38    to  FIG.  40   , the structure of a wireless power transmission device  1 E and a movable body  60 E is described.  FIG.  38    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to the sixth embodiment.  FIG.  39    is a diagram illustrating an overall configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to the sixth embodiment.  FIG.  40    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the sixth embodiment. In the sixth embodiment, pilot transmitter  5  and the arrival direction detecting device are unnecessary. A movable body  60 E does not include pilot transmitter  5 . Movable body  60 E includes a positioning sensor  65 , an attitude sensor  66 , and a movable body position sender  67 . Positioning sensor  65  measures the position of movable body  60 E. Positioning sensor  65  is also used as a time device  16 . Positioning sensor  65  is, for example, a GPS receiver. Instead of a GPS receiver, any device that can measure the position in three-dimensional space of movable body  60 E can be used as positioning sensor  65 . Attitude sensor  66  measures the attitude of movable body  60 E. Movable body position sender  67  performs a process of sending periodically movable body position  81  measured by positioning sensor  65  and attitude data  82  measured by attitude sensor  66  to control device  10 E. When the movable body position measured by positioning sensor  65  is not close to the position of power reception device  3 , control device  10 E corrects the movable body position using the attitude measured by attitude sensor  66  and structure data representing the structure of movable body  60 E and determines the position of power reception device  3 . When movable body  60 E is small and the position in three-dimensional space of movable body  60 E is considered as the position of power reception device  3 , attitude sensor  66  is not necessarily provided. 
     In movable body  60 E, a data storage device  21 E is modified. Data storage device  21 E also stores movable body position  81  and attitude data  82 . Movable body position  81  is a three-dimensional position of movable body  60 E measured by positioning sensor  65 . Attitude data  82  is data representing the attitude of movable body  60 E measured by attitude sensor  66 . 
     Control device  10 E includes a positioning sensor  40  and a movable body position determiner  41 . Positioning sensor  40  measures the position of wireless power transmission device  1 E. Positioning sensor  40  is also used as a time device  15 . Movable body position determiner  41  determines the position of movable body  60 E from the movable body position and the attitude data of movable body  60 E sent from movable body  60 E. Once the position of movable body  60 E is determined, the presence direction that is the direction in which movable body  60 E is present viewed from the position of power transmission antenna  50  is also determined. Movable body position determiner  41  is a presence direction determiner that determines the presence direction. Positioning sensor  40  is, for example, a GPS receiver. Instead of a GPS receiver, any device that can measure the position in three-dimensional space of wireless power transmission device  1 E can be used as positioning sensor  40 . When wireless power transmission device  1 E is not moved, positioning sensor  40  may not be equipped. 
     In control device  10 E, a data storage  25 E, a radiation direction determiner  33 E, and a radio wave radiation controller  34 E are modified. Data storage  25 E includes movable body structure data  83 , power transmission device position  84 , movable body position  81 , attitude data  82 , and power reception device position  85 . In movable body position  81 , the position data of movable body  60 E measured by positioning sensor  65  and sent from movable body  60 E is recorded. In attitude data  82 , the attitude data of movable body  60 E measured by attitude sensor  66  and sent from movable body  60 E is recorded. Attitude data  82  is, for example, the direction in which movable body  60 E is directed (nose direction). In power reception device position  85 , the position of power reception device  3  determined by movable body position determiner  41  is recorded. In movable body structure data  83 , data representing the structure of movable body  60 E is recorded, which is used when power reception device position  85  is obtained from movable body position  81  and attitude data  82 . Movable body structure data  83  is, for example, data representing that the position of power reception device  3  is 10 m to the back of the position of positioning sensor  65  in the nose direction. Data storage  25 E is a movable body data storage that stores the movable body structure data. 
     Movable body position determiner  41  is a power reception device position determiner that determines power reception device position  85  using movable body structure data  83 , movable body position  81 , and attitude data  82 . When attitude data  82  is, for example, the nose direction of movable body  60 E, the position in the positional relation specified by movable body structure data  83  in the direction indicated by attitude data  82  with respect to movable body position  81  is power reception device position  85 . Power transmission device position  84  is the position of wireless power transmission device  1 E (strictly speaking, power transmission antenna  50 ) measured by positioning sensor  40 . The movable body position determiner may determine the movable body position measured by positioning sensor  65 . Power transmission device position  84  is a power transmission antenna position that is the position of power transmission antenna  50 . 
     Radiation direction determiner  33 E determines the radiation direction of power transmission radio wave  2  toward power reception device  3  (power transmission direction), based on power reception device position  85  and power transmission device position  84 . Radio wave radiation controller  34 E determines the phase and amplitude of element radio wave  2 E p  radiated by each element antenna  8   p , also using the distance (power transmission distance) between wireless power transmission device  1 E and power reception device  3 , and controls each element module  9  such that the determined phase and amplitude is obtained. In the case of a far field, the power transmission distance is not necessary. When the power transmission distance is not considered as a far field, it is necessary to determine the phase and amplitude of element radio wave  2 E p  radiated by each element antenna  8   p  also in consideration of the power transmission distance. 
     The operation is described.  FIG.  41    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the sixth embodiment. In  FIG.  41   , points different from  FIG.  8    in the first embodiment are described. The process includes steps S 21  to S 26  instead of S 11  to S 13 . At step S 21 , positioning sensor  65  included in movable body  60 E measures movable body position  81  that is the position of movable body  60 E, and attitude sensor  66  measures attitude data  82 . At step S 22 , movable body  60 E sends movable body position  81  and attitude data  82 , which are received by control device  10 E. At step S 23 , movable body position determiner  41  determines power reception device position  85 , using movable body structure data  83 , movable body position  81 , and attitude data  82 . At step S 24 , the presence direction that is the direction in which power reception device position  85  is present viewed from power transmission device position  84  is determined based on power reception device position  85  and power transmission device position  84 . At step S 25 , radiation direction determiner  33 E determines the power transmission direction (ψ AZ , ψ EL ) toward power reception device  3 . At step S 26 , radio wave radiation controller  34 E determines the phase and amplitude of element radio wave  2 E p  radiated by each element antenna  8   p , using the power transmission direction (ψ AZ , ψ EL ) and the power transmission distance, and determines the phase shift amount and the amplification factor of each element module  9  such that the determined phase and amplitude is obtained. Wireless power transmission device  1 E radiates power transmission radio wave  2  in the power transmission direction at S 01 , with the phase shift amount and amplification factor determined at S 26 . After S 26  is performed, the process returns to S 21 . Control device  10 E performs the process at S 21  to S 26  repeatedly in predetermined cycles. 
     Wireless power transmission device  1 E operates similarly to wireless power transmission device  1  and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. 
     Since the position of movable body  60 E is measured, the pilot transmitter, the pilot antenna, and the arrival direction detecting device are unnecessary. When movable body  60  is large, the position of power reception device  3  is determined also in consideration of the attitude of movable body  60 E measured by attitude sensor  65 , and therefore power can be transmitted to power reception device  3  accurately and efficiently. When movable body  60  is small, the direction toward the movable body position measured by positioning sensor  66  is set as the presence direction. 
     The use of the distance between movable body  60 E and wireless power transmission device  1 E can improve the accuracy of the REV method and enables more accurate power transmission to the position of power reception device  3  during power transmission. 
     Seventh Embodiment 
     In a seventh embodiment, the first embodiment is modified such that the position of the movable body is measured on the ground. The movable body and the wireless power transmission device are modified. 
     Referring to  FIG.  42    to  FIG.  44   , the structure of a wireless power transmission device  1 F and a movable body  60 F is described.  FIG.  42    is a schematic diagram illustrating a configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to the seventh embodiment.  FIG.  43    is a diagram illustrating an overall configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to the seventh embodiment.  FIG.  44    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the seventh embodiment. Movable body  60 F does not include pilot transmitter  5 . Movable body  60 F does not include the positioning sensor and the like. A laser positioning device  42  is installed in the neighborhood of wireless power transmission device  1 F. Laser positioning device  42  measures the position of power reception device  3  included in movable body  60 F. Power reception device position  85 F representing the position of power reception device  3  measured by laser positioning device  42  is inputted to a control device  10 F in predetermined cycles during power transmission to movable body  60 F. Laser positioning device  42  is a movable body position measuring device that measures the movable body position. 
     Laser positioning device  42  transmits a laser beam  43  in each direction and receives reflected laser beam  44  reflected by movable body  60 F that is a positioning target. The direction in which movable body  60 F is present is determined from the direction of reflected laser beam  44 , and the distance to movable body  60 F is determined from the time until reflected laser beam  44  is received since laser beam  43  is emitted. When movable body  60 F is large and measurement is performed with a wide range of reflected laser beam  44 , power reception device position  85 F that is the position of power reception device  3  is also determined. Laser positioning device  42  has data representing a pattern of reflection from movable body  60 F. The reflection pattern also includes data indicating the power reception device position in the reflection pattern. Laser positioning device  42  matches the obtained reflected laser beam  43  actually with a pattern to determine power reception device position  85 F. Reflection patterns of movable body  60 F in which movable body  60 F is viewed from several directions are prepared. The positioning device that measures the position of power reception device  3  may use radio waves or acoustic waves instead of laser beams. 
     In control device  10 F, a data storage  25 F and a radiation direction determiner  33 E are modified. Data storage  25 F includes power reception device position  85 F instead of arrival direction data  78 . Power reception device position  85 F of power reception device  3  inputted from laser positioning device  42  is set in power reception device position  85 F. 
     Radiation direction determiner  33 E has a configuration similar to that included in control device  10 E and operates similarly. 
     The operation is described.  FIG.  45    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the seventh embodiment. In  FIG.  45   , points different from  FIG.  37    in the sixth embodiment are described. S 21 F and S 22 F are modified, and S 23  is deleted. At step S 21 F, laser positioning device  42  measures power reception device position  85 F. At step S 22 F, power reception device position  85 F detected by laser positioning device  42  is inputted to control device  10 F. S 24  to S 26  are similar to those in  FIG.  37    in the sixth embodiment. After S 26  is performed, the process returns to S 21 F. Control device  10 F performs the process at S 21 F to S 26  repeatedly in predetermined cycles. 
     Wireless power transmission device  1 F operates similarly to wireless power transmission device  1  and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. 
     The movable body is required to have neither the positioning sensor nor the pilot transmitter. Even when the movable body is small and has a limitation in a device to be installed, wireless power transmission device  1 F can transmit power to the movable body accurately and efficiently. 
     The movable body position measuring device that measures the movable body position may radiate distance-measurement waves such as laser light, non-laser light, radio waves, ultrasonic waves, or the like and receive distance-measurement reflected waves reflected by the movable body. The distance to the movable body may be measured based on the elapsed time from transmission of a distance-measurement wave to reception of a distance-measurement reflected wave, and the movable body position may be measured from the measured distance and the direction in which the distance-measurement reflected wave arrives. 
     Eighth Embodiment 
     In an eighth embodiment, the first embodiment is modified such that a part of the process of calculating the element electric field vector by the REV method is executed in a movable body so that the volume of data transmitted from the movable body to the control device is reduced. In the eighth embodiment, compared with the first embodiment, a control device  10 G, an on-board control device  19 G, and a data storage device  21 G are modified. A configuration of the power transmission system for the movable body by the wireless power transmission device according to the eighth embodiment is described referring to  FIG.  46   .  FIG.  46    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the eighth embodiment. In  FIG.  46   , points different from  FIG.  5    in the first embodiment are described. 
     Measurement periods Tp are a plurality of periods given by the data acquisition command. Each measurement period corresponds to a period in which the operating phase shifter changes the phase shift amount. Data storage device  21 G mounted on movable body  60 G also stores maximum/minimum time  86  and maximum/minimum amplitude value  87 . Maximum/minimum time  86  is time Tpmax when electric field strength Cp(t) detected actually in measurement period Tp is largest and time Tpmin when electric field strength Cp(t) is smallest. Maximum/minimum amplitude value  87  is maximum value Cpmax and minimum value Cpmin of electric field strength Cp(t) in measurement period Tp. Maximum/minimum time  86  and maximum/minimum amplitude value  87  are sent from on-board control device  19 G to control device  10 G as a reply to data acquisition command  73 G. Maximum/minimum time  86  and maximum/minimum amplitude value  87  are electric field change data that represents change in electric field in measurement period Tp. Only maximum/minimum time  86  may be sent as electric field change data. 
     On-board control device  19 G does not include transmission data generator  64  and includes a measurement data analyzer  35 G. Measurement data analyzer  35 G detects time Tpmax and time Tpmin from electric field strength Cp(t) measured actually in measurement period Tp. Maximum value Cpmax and minimum value Cpmin of electric field strength Cp(t) also are detected. Measurement period Tp is an analysis period in which electric field strength Cp(t) measured in this period is analyzed. Time Tpmax and time Tpmin stored as maximum/minimum time  86  in data storage device  21 G are the phase shift amount detection time obtained by analyzing electric field strength Cp(t) measured in each analysis period. Measurement data analyzer  35 G detects the phase shift amount detection time for each analysis period. 
     Movable body communication device  20  sends maximum/minimum time  86  and maximum/minimum amplitude value  87  to control device  10 G. Movable body communication device  20  does not send electric field strength Cp measured in measurement period Tp, that is, detection data  71  to control device  10 G. 
     Data storage  25 G included in control device  10 G stores maximum/minimum time  86  and maximum/minimum amplitude value  87  sent from movable body  60 G. Since detection data  71  is not sent from movable body  60 G, detection data  71  is not stored in data storage  25 G. 
     Element electric field calculator  29 G does not include measurement data analyzer  35 . Operation phase shift amount acquirer  36  obtains the operation phase shift amount of phase shifter  13   p  recorded in phase operation data  75  at time Tpmax and time Tpmin that are maximum/minimum time  86 . Element electric field vector calculator  37  calculates the phase of element electric field vector  76  (element electric field phase) generated by element antenna  8  corresponding to phase shifter  13   p  to change the phase, and the amplitude of element electric field vector  76 . Element antenna  8  corresponding to phase shifter  13   p  is element antenna  8  receiving an element transmission signal outputted by phase shifter  13   p . Element electric field vector calculator  37  calculates the phase and amplitude of element electric field vector  76  from the operation phase shift amount of phase shifter  13   p  that is recorded in phase operation data  75  at time Tpmax and time Tpmin, and maximum value Cpmax and minimum value Cpmin of electric field strength Cp(t). Phase offset value calculator  31  calculates phase offset value  77  for each phase shifter  13  from the phase of element electric field vector  76  of each phase shifter  13 . Phase offset value setter  32  sets phase offset value  77  in each phase shifter  13 . 
     The operation is described.  FIG.  47    is a flowchart illustrating the procedure of calculating the element electric field vector of a radio wave radiated by each element antenna by the REV method in the wireless power transmission device according to the eighth embodiment. 
     In  FIG.  47   , points different from  FIG.  9    in the first embodiment are described. S 37  is changed to S 37 G, and S 38  is changed to S 38 G. Step S 47  is added before step S 37 G. At S 47 , measurement data analyzer  35 G included in movable body  60 G detects maximum value Cpmax of electric field strength Cp in measurement period Tp and time Tpmax that is the time when maximum value Cpmax is taken. Further, minimum value Cpmin of electric field strength Cp in measurement period Tp and time Tpmin that is the time when minimum value Cpmin is taken are detected. 
     The process at S 47  corresponds to the process at S 39  in  FIG.  40   . In  FIG.  47   , therefore, S 39  does not exist. 
     At step S 37 G, movable body communication device  20  included in movable body  60 G sends time Tpmax and time Tpmin as maximum/minimum time  86  together with maximum value Cpmax and minimum value Cpmin as maximum/minimum amplitude value  87  to communication device  30  included in control device  10 G. 
     At step S 38 G, communication device  30  receives time Tpmax and time Tpmin together with maximum value Cpmax and minimum value Cpmin. 
     Subsequently to S 38 G, S 40  is performed. The subsequent process is similar to that in  FIG.  40   . 
     In the power transmission system for the movable body in the eighth embodiment, in addition to the effect obtained by the first embodiment, the volume of data sent from movable body  60 G to execute the REV method can be reduced. 
     Ninth Embodiment 
     In a ninth embodiment, the first embodiment is modified such that the process of calculating the element electric field vector by the REV method is executed in the movable body so that the volume of data sent from the movable body to the control device is reduced. In the REV method scenario, the operation phase shift amount of each phase shifter is discrete and the time to be constant taking each of operation phase shift amounts is set to an appropriate length of time. By doing so, an error can be reduced when the operation phase shift amount is obtained from the time using the REV method scenario instead of the record of actual change in operation phase shift amount of the phase shifter. 
     In a wireless power transmission device  1 H, compared with wireless power transmission device  1 , a control device  10 H, an on-board control device  19 H, and a data storage device  21 H are modified. A configuration of the power transmission system to the movable body by the wireless power transmission device according to the ninth embodiment is described referring to  FIG.  48   .  FIG.  48    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the ninth embodiment. In  FIG.  48   , points different from  FIG.  46    in the eighth embodiment are described. 
     Data acquisition command  73 H is a command to instruct on-board control device  19 H to calculate an element electric field vector. Data acquisition command  73 H is sent from control device  10 H to on-board control device  19 H. On-board control device  19 H generates detection data  71 . On-board control device  19 H calculates element electric field vector  76  of each element module based on detection data  71  and REV method scenario  74 . On-board control device  19 H sends element electric field vector  76  to control device  10 H. 
     Control device  10 H does not include element electric field calculator  29 . A data acquisition command generator  28 H is modified. Data storage  25 H does not store maximum/minimum time  86  and maximum/minimum amplitude value  87 . Data storage  25 H stores REV method scenario  74 H. REV method scenario  74 H is modified from REV method scenario  74  so that element electric field vector  76  is calculated easily also in on-board control device  19 H. REV method scenario  74 H is described later. 
     In control device  10 H, data acquisition command generator  28 H is modified to generate data acquisition command  73 H. Data acquisition command  73 H is passed by movable body communication device  20  to on-board control device  19 H. Data acquisition command  73 H includes the REV method start time. REV method start time  88  is the time when REV method executor  27 H included in control device  10 H starts execution of REV method scenario  74 H. In REV method scenario  74 H, the execution start is a reference event, and other events are non-reference events in which the time is expressed by a relative time from the execution start. 
     For example, when the REV method scenario is defined to have a plurality of reference events, data acquisition command  73 H may be sent multiple times, or a command to indicate the time of a reference event may be sent one or more times and data acquisition command  73 H may be sent once. 
     On-board control device  19 H includes a data acquisition command interpreter  63 H and an element electric field calculator  29 H. Data storage device  21 H stores REV method scenario  74 H, REV method start time  88 , measurement period data  70 , detection data  71 , maximum/minimum time  86 , maximum/minimum amplitude value  87 , and element electric field vector  76 . REV method scenario  74 H is stored into data storage device  21 H before movable body  60 H takes off. 
     REV method scenario  74 H stored in data storage device  21 H may be identical to that included in control device  10 H or may include only data necessary for element electric field calculator  29 H. Maximum/minimum time  86  and maximum/minimum amplitude value  87  are data to be used for element electric field calculator  29 H to obtain element electric field vector  76  and therefore they may be internal data of element electric field calculator  29 H and is not necessarily stored in data storage device  21 H. 
     Upon receiving data acquisition command  73 H, data acquisition command interpreter  63 H extracts REV method start time  88  from data acquisition command  73 H and stores the extracted REV method start time  88  into data storage device  21 H. REV method scenario  74 H is referred to set measurement period data  70  that is measurement period Tp for each operating phase shifter. In measurement period data  70 , the relative time is replaced by the time, using REV method start time  88 . Setting a plurality of measurement periods Tp based on REV method start time  88  and REV method scenario  74 H may be given to the eighth embodiment and the like in which time Tpmax and time Tpmin that are the phase shift amount detection time are obtained in the movable body. 
     Detector controller  61  generates detection data  71  in a measurement period specified by measurement period data  70 . Detection data time adder  62  adds time data  72  representing the time of measurement to detection data  71 . Detection data  71  is stored into data storage device  21 H. 
     Element electric field calculator  29 H calculates element electric field vector  76 , based on detection data  71  measured in the period specified by measurement period data  70 , and REV method scenario  74 H. Phase operation data  75  is not sent from control device  10 H to on-board control device  19 H. Element electric field calculator  29 H therefore refers to REV method scenario  74 H instead of phase operation data  75 . 
     Element electric field calculator  29 H includes measurement data analyzer  35 G, an operation phase shift amount acquirer  36 H, and an element electric field vector calculator  37 H. Measurement data analyzer  35 G detects time Tpmax and time Tpmin when electric field strength Cp(t) measured actually in measurement period Tp is largest or smallest, in the same way as in the eighth embodiment. Instead of obtaining the time of maximum or minimum strictly, the time in the vicinity of the center of a period in which electric field strength Cp(t) takes a value close to the maximum or the minimum, excluding fluctuations due to noise, is detected as time Tpmax and time Tpmin. Maximum value Cpmax and minimum value Cpmin of electric field strength Cp(t) also are detected. Time Tpmax and time Tpmin are stored as maximum/minimum time  86  into data storage device  21 H. Maximum value Cpmax and minimum value Cpmin are stored as maximum/minimum amplitude value  87  into data storage device  21 H. 
     Operation phase shift amount acquirer  36 H converts time Tpmax and time Tpmin into relative times by subtracting REV method start time  88 . The operation phase shift amount spmax at time Tpmax and the operation phase shift amount sprain at time Tpmin are obtained by referring to REV method scenario  74 H by time Tpmax and time Tpmin converted into relative times. The relative time in REV method scenario  74 H may be converted into the time by adding REV method start time  88 , and REV method scenario  74 H may be referred to by time Tpmax and time Tpmin. 
     Element electric field vector calculator  37 H calculates the element electric field vector of each element module from operation phase shift amount spmax and operation phase shift amount spmin, and maximum value Cpmax and minimum value Cpmin. 
     REV method scenario  74 H is modified so that the operation phase shift amount is acquired reliably even when element electric field calculator  29 H does not refer to phase operation data  75 . In REV method scenario  74 H, the operation phase shift amount of each phase shifter  13  is changed discretely. The period in which phase shifter  13  keeps constant with the specified operation phase shift amount is set to be equal to or longer than a predetermined length. That is, in REV method scenario  74 H, the phase operating pattern is defined such that the time in which the operating phase shifter (phase shifter  13  for which the phase shift amount is operated) takes each of different operation phase shift amounts is equal to or longer than a predetermined duration time. 
     When REV method executor  27 H controls phase shifter  13  in accordance with REV method scenario  74 H, an error may be generated in the timing for changing the operation phase shift amount actually. Even when an error is generated, since the period in which the operation phase shift amount is constant is equal to or longer than a predetermined length, REV method scenario  74 H can be referred to acquire operation phase shift amount spmax and operation phase shift amount spmin at time Tpmax and time Tpmin with a reduced error. The length of period in which the operation phase shift amount is constant is determined as appropriate in consideration of the magnitude of error of fluctuating execution time. 
     The operation is described.  FIG.  49    is a flowchart illustrating the procedure of calculating an element electric field vector of a radio wave radiated by each element antenna by the REV method in the wireless power transmission device according to the ninth embodiment. 
     In  FIG.  49   , points different from  FIG.  47    in the eighth embodiment are described. S 37 G and S 38 G are removed and steps S 48  to S 51  are added. S 47  to S 50  are the process performed in movable body  60 H. At S 47 , measurement data analyzer  35 G detects time Tpmax and time Tpmin in the same way as in the eighth embodiment. Subsequently to step S 47 , at step S 48 , operation phase shift amount acquirer  36 H refers to REV method scenario  74 H to detect the operation phase shift amount spmax of phase shifter  13   p  at time Tpmax. The operation phase shift amount spmin of phase shifter  13   p  at time Tpmin is also detected. 
     At step S 49 , element electric field vector calculator  37 H calculates the phase and amplitude of element electric field vector Ep from operation phase shift amount spmax, operation phase shift amount spmin, and maximum value Cpmax and minimum value Cpmin of electric field strength Cp. The phase of element electric field vector Ep is calculated based on the average of the phase calculated from operation phase shift amount spmax and the phase calculated from operation phase shift amount spmin and the electric field strength change ratio (|Cpmax|/|Cpmin|). 
     At step S 50 , movable body communication device  20  mounted on movable body  60 H sends element electric field vector Ep to communication device  30  included in control device  10 G. At step S 51 , communication device  30  receives element electric field vector Ep. 
     Subsequently to S 51 , at S 42 , it is checked whether there is any phase shifter  13  not yet processed. 
     In the ninth embodiment, in addition to the effect obtained by the first embodiment, the volume of data sent from movable body  60 G can be reduced because the REV method is executed in the movable body. Furthermore, it is not necessary for control device  10 H to calculate element electric field vector Ep by the REV method. 
     The on-board control device may carry out up to the process of obtaining operation phase shift amount spmax and operation phase shift amount spmin of the operating phase shifter, and the process of calculating element electric field vector Ep from operation phase shift amount spmax and operation phase shift amount spmin may be executed in the control device. In this case, operation phase shift amount spmax and operation phase shift amount spmin are sent from the on-board control device to the control device. 
     Tenth Embodiment 
     In a tenth embodiment, not only the presence direction of the movable body but also a three-dimensional position of the movable body (called movable body position) is measured, and the wireless power transmission device radiates a power transmission radio wave (power transmission beam) so that the maximum electric power can be received at the movable body position. The tenth embodiment is an embodiment that can handle a case where a power transmission antenna is increased in scale or power is transmitted to a movable body in a near field and therefore the distance to a movable body is not a far field. In the tenth embodiment, the movable body position is measured during execution of the REV method and a power transmission beam tracks the changing movable body position. Referring to  FIG.  50   , a configuration of a wireless power transmission system for a movable body according to the tenth embodiment is described. A wireless power transmission device  1 J and a movable body  60 J are modified. 
     Wireless power transmission device  1 J can send a pulse-modulated power transmission radio wave  2 J. Movable body  60 J can send a pulse-modulated pilot signal  4 J. In wireless power transmission device  1 J, a distance G between power transmission antenna  50 J and movable body  60 J is measured based on the time until the pulse-modulated pilot signal  4 J is received since the pulse-modulated power transmission radio wave  2 J is transmitted. 
     Wireless power transmission device  1 J differs from wireless power transmission device  1  in that power transmission antenna  50 J and a control device  10 J are modified. Power transmission antenna  50 J transmits pulse-modulated power transmission radio wave  2 J. Movable body  60 J returns pulse-modulated pilot signal  4 J for power transmission radio wave  2 J. Control device  10 J controls power transmission antenna  50 J such that pulse-modulated power transmission radio wave  2 J can be transmitted. Control device  10 J measures distance G. 
     Referring to  FIG.  51   , a configuration of wireless power transmission device  1 J and movable body  60 J is described.  FIG.  51    is a diagram illustrating an overall configuration of a wireless power transmission system for a movable body using a wireless power transmission device according to the tenth embodiment. In  FIG.  51   , points different from  FIG.  2    in the first embodiment are described. 
     In wireless power transmission device  1 J, power transmission antenna  50 J, arrival direction detecting device  7 J, and control device  10 J are modified. In power transmission antenna  50 J, an element module  9 J is modified. Element module  9 J includes a pulse modulation switch  45  for pulse-modulating power transmission radio wave  2 J. Pulse modulation switch  45  is controlled by control device  10 J to switch between radiation and non-radiation of power transmission radio wave  2 J. Pulse modulation switch  45  is turned on and off in predetermined cycles so that power transmission radio wave  2 J can be pulse-modulated. When pulse modulation switch  45  is kept on, power transmission radio wave  2 J not pulse-modulated is radiated. Control device  10 J controls on and off of pulse modulation switch  45  in a predetermined length of time TO so that pulse-modulated power transmission radio wave  2 J is radiated from power transmission antenna  50 J. Pulse modulation switch  45  is usually kept on state and does not pulse-modulate power transmission radio wave  2 J. 
     In arrival direction detecting device  7 J, a pilot receiver  24 J is modified. Pilot receiver  24 J receives pulse-modulated pilot signal  4 J and detects the starting part and the end part of pulse modulation to notify control device  10 J. The signal given is called a pulse modulation detection signal  89  (illustrated in  FIG.  52   ). Control device  10 J receiving pulse modulation detection signal  89  records the reception time of pilot signal  4 J. The modification made in control device  10 J is described referring to  FIG.  52   . 
     In movable body  60 J, a pilot transmitter  5 J, a detector  181 , and an on-board control device  19 J are modified. Pilot transmitter  5 J transmits pulse-modulated pilot signal  4 J. Although not illustrated in the drawings, pilot transmitter  5 J contains a switch to switch between transmission and non-transmission of pilot signal  41 . The switch is controlled by on-board control device  19 J. In a period in which the switch is turned on and off in predetermined cycles, pilot transmitter  5 J transmits pulse-modulated pilot signal  4 J. In a period in which the switch is kept on, pilot transmitter  5 J transmits pilot signal  4 J not pulse-modulated. 
     Detector  18 J receives pulse-modulated power transmission radio wave  2 J and detects the starting part and the end part of pulse modulation to notify on-board control device  19 J. On-board control device  19 J receiving the notification records the reception time of power transmission radio wave  2 J and performs control such that pilot communication device  5 J starts and ends pulse modulation. Pilot communication device  51  starts transmission of pulse-modulated pilot signal  4 J after elapse of a predetermined time T 1  since pulse-modulated power transmission radio wave  2 J is received by detector  18 J. The modification made in on-board control device  19 J is described referring to  FIG.  52   . 
     Referring to  FIG.  52   , a functional configuration of wireless power transmission device  1 J and movable body  60 J is described.  FIG.  52    is a block diagram illustrating a functional configuration of the wireless power transmission device and the movable body according to the tenth embodiment. In  FIG.  52   , points different from  FIG.  5    in the first embodiment are described. 
     On-board control device  19 J includes a pulse modulation manager  68  additionally. Pulse modulation manager  68  receives a detection signal indicating the starting part and the end part of pulse modulation of power transmission radio wave  2 J sent from detector  18 J and controls whether to make pilot transmitter  5 J to perform pulse modulation or not. Upon receiving a notification that pulse modulation of power transmission radio wave  2 J is started, pulse modulation manager  68  acquires the reception time of notification (start notification time). Pilot transmitter  5 J is controlled to start pulse modulation of pilot signal  4 J at the time when time T 1  has elapsed since the start notification time. Upon receiving a notification that pulse modulation of power transmission radio wave  2 J is ended, pulse modulation manager  68  acquires the reception time of notification (end notification time). Pilot transmitter  5 J is controlled end pulse modulation of pilot signal  4 J at the time when a predetermined time T 1  has elapsed since the end notification time. 
     Control device  10 J does not include radiation direction determiner  33  and includes a distance meter  46  and a radiation target position determiner  47 . In control device  10 J, a data storage  25 J and a radio wave radiation controller  34 J are modified. Radiation target position determiner  47  determines a radiation target position determined by the radiation direction and the distance from power transmission antenna  50 J. The radiation target position is a range of position in three-dimensional space set to be a target to radiate a radio wave by power transmission antenna  50 J. Power transmission antenna  50 J can change the radiation target position and radiate a radio wave to the changed radiation target position. 
     Distance meter  46  measures the distance from power transmission antenna  50 J to movable body  60 J (strictly speaking, power reception device  3 ). The distance from power transmission antenna  50 J to movable body  60 J is called movable body distance. Distance meter  46  obtains a movable body distance from the time until pilot signal  4 J is received since power transmission radio wave  2 J is transmitted. Distance meter  46  is a movable body distance measurer that measures the movable body distance based on the elapsed time from transmission of a power transmission radio wave to the movable body to reception of a pilot signal transmitted in response to the power transmission radio wave by the wireless power transmission device. 
     Movable body  60 J is present at a position at the movable body distance in the presence direction when viewed from power transmission antenna  50 J. The position in three-dimensional space in which movable body  60 J is present is the movable body position. Arrival direction detecting device  7  and distance meter  46  constitute a movable body position determiner that determines the movable body position from the presence direction and the movable body distance. The movable body position determiner that determines the movable body position that is the position where the movable body is present may determine the movable body position by any other method. 
     Distance meter  46  records the measured movable body distance as target position distance data  97  in data storage  25 J so that power transmission radio wave  2 J can be radiated using the movable body position as the radiation target position. Radio wave radiation controller  34 J controls element modules  9  such that power transmission antennas  50 J radiate power transmission radio waves  2 J with the phases matched at the radiation target position. 
     In wireless power transmission device  1 J, the radiation target position is set to a single point in three-dimensional space. Setting the radiation target position to a single point is an example of the radiation target position that is a range of position in three-dimensional space. The radiation target position may be a range of position instead of the position of a single point. The size of the range of the radiation target position may be determined based on the measurement accuracy of the arrival direction and the movable body distance. The size of the range of the radiation target position may be determined depending on the characteristics of the power transmission beam radiated by the wireless power transmission device. The size of the range of the radiation target position may be fixed or may be changed according to the situation. 
     The target position distance is the distance to a point included in the radiation target position. For example, the distance to a position that is the center of the radiation target position may be set as the target position distance. Alternatively, for example, the distance to a point at a predetermined position on the boundary of the radiation target position may be set. In wireless power transmission device  1 J, the radiation target position is determined to include the movable body position so that power can be transmitted to the movable body. 
     Data storage  25 J has radiation target position data  94  instead of radiation direction data  79 . Data storage  25 J also has pulse transmission time  95 , pulse reception time  96 , and target position distance data  97 . Radiation target position data  94  is data representing a radiation target position that is the position at a predetermined distance (target position distance) in a predetermined direction (radiation direction) from power transmission antenna  50 J. The radiation direction is a direction determined based on arrival direction data  78 . Target position distance data  97  is data representing a target position distance. Pulse transmission time  95  is data representing the time related to the time when power transmission radio wave  2 J is sent. Pulse reception time  96  is data representing the time related to the time when pilot signal  4 J is received. Distance meter  46  sets pulse transmission time  95  and pulse reception time  96 , measures the movable body distance based on pulse transmission time  95  and pulse reception time  96 , and sets the measured movable body distance as target position distance data  97  in data storage  25 J. 
     Distance meter  46  controls on and off of pulse modulation switch  45  to pulse-modulate power transmission radio wave  2 J. Distance meter  46  records the time when pulse modulation of power transmission radio wave  2 J is started and ended as pulse transmission time  95 . Distance meter  46  sets the time when pulse modulation detection signal  89  for the start and the end of pulse modulation of pilot signal  4 J is received, as pulse reception time  96 . Distance meter  46  obtains the average T 2  of the time difference between pulse reception time  96  and pulse transmission time  95  for the start and the time difference between pulse reception time  96  and pulse transmission time  95  for the end. Furthermore, time T 3 =T 2 −T 1  is obtained by subtracting T 1  from T 2 . T 3  is the time required for power transmission radio wave  2 J and pilot signal  4 J going to movable body  60 J and returning. Distance meter  46  obtains the target position distance based on T 3 . The target position distance is a distance obtained by correcting the distance calculated from T 3  in consideration of the positional relation between pilot transmitter  5 J and power reception device  3  and the like. Distance meter  46  sets the obtained target position distance as target position distance data  97 . 
     Radiation target position determiner  47  determines the radiation target position based on arrival direction data  78  and target position distance data  97  and sets the determined radiation target position as radiation target position data  94 . Radiation target position determiner  47  sets the direction opposite to the direction represented by arrival direction data  78  as the radiation direction and determines the position of the distance represented by target position distance data  97  in the radiation direction from power transmission antenna  50 J as the radiation target position. 
     The moving speed of movable body  60 J may be estimated based on the temporal transition of arrival direction data  78  and target position distance data  97 , and the radiation target position may be determined so as to include the estimated position where movable body  60 J is present after a predetermined time in consideration of the moving speed. The position determined by arrival direction data  78  and target position distance data  97  at each point of time may be stored as the movable body position, the position of the movable body after a predetermined time may be predicted based on the temporal transition of the stored movable body position, and the radiation target position may be determined so as to include the predicted position of the movable body. 
     Radiation target position determiner  47  determines the radiation target position as a relative position to the power transmission antenna so as to include the movable body position by controlling the phase shift amount that is the amount by which phase shifter  13  changes the phase of a transmission signal. 
     Radio wave radiation controller  34 J generates radiation command values  80  such that power transmission antennas  50 J radiate power transmission radio waves  2 J with the phases matched at the radiation target position stored in radiation target position data  95 . Radiation command value  80  is sent as a power transmission control signal to wireless power transmission device  1 . Each element module  9 J is controlled such that the corresponding element antenna  8  radiates element radio wave  2 E p  having the phase and amplitude specified by radiation command value  80 . Radio wave radiation controller  34 J is a radiation target position changer that radiates power transmission radio wave  2 J to the radiation target position by controlling the phase shift amount of phase shifter  13  included in each element module  9 J. The phase shift amount changed by radio wave radiation controller  34 J is called radiation target position change phase shift amount. Since the radiation target position is determined by the radiation direction and the distance, radio wave radiation controller  34 J can also be recognized as a radiation direction changer. 
     Power transmission radio waves  2 J having the phases matched at the radiation target position mean that the maximum value of the phase difference at the radiation target position of the phase of element radio wave  2 E p  radiated by each element antenna  8   p  is equal to or less than a predetermined upper limit value. When the radiation target position is a single point, it is preferable to perform control such that the phase difference between element radio waves  2 E p  at the radiation target position is zero. When the radiation target position has a range, the phase difference between element radio waves  2 E p  is controlled to be equal to or less than the upper limit value at each point in the range. The phase difference between element radio waves  2 E p  may be controlled to be zero at a point in the range of radiation target position. The sum of phase differences between element radio waves  2 E p  at the points in the range of radiation target position can be controlled to be minimized. Alternatively, the following method may be possible. Among the points included in the ranged defined by the radiation target position, a point at which the distance to the position of each element antenna  8   p  is largest (maximum distance point), a point at which the distance is smallest (minimum distance point), and a midpoint of the line connecting the maximum distance point and the minimum distance point (median distance point) are obtained. The phases of element radio waves  2 E p  radiated by element antennas  8   p  are controlled to be the same at the median distance point of element antennas p . 
     In the tenth embodiment, power transmission radio wave  2 J, power transmission antenna  50 J, element module  9 J, movable body  60 J, and the like are modified in order to obtain distance G between wireless power transmission device  1 J and movable body  60 J. These modifications have nothing to do with wireless power transmission by wireless power transmission device  1 J. In a description as to how radio wave radiation controller  34 J determines radiation command value  80 , power transmission radio wave  2 , power transmission antenna  50 , element module  9 , movable body  60 , and the like are used. 
     How to determine a command value of the phase to each element module  9  such that the phase of element radio wave  2 E p  radiated by each element antenna  8  is matched at the radiation target position is described. For this, the following is assumed. 
     (A) Power transmission antenna  50  has element antennas  8  arranged linearly in one dimension. 
     (B2) The distance of movable body  60  from power transmission antenna  50  is shorter than the distance at which a far field is established. 
     (C) Change in power transmission direction in a plane having the direction in which element antennas  8  are arranged and the front direction of power transmission antenna  50  is studied. When the power transmission direction is matched with the front direction of power transmission antenna  50 , the angle of the power transmission direction is zero degrees. 
     (D2) Change in distance between wireless power transmission device  1 J and power reception device  3  is also taken into consideration. 
     The following variables are defined for explanation. Variables whose meaning is changed are also described. 
     P S : the position of wireless power transmission device  1 . The position at the center of power transmission antenna  50  (the position Nm). Called power transmission device position or power transmission antenna position. 
     P T : the radiation target position. The relative position of power reception device  3  to power transmission device position P S . 
     ψ: the power transmission direction. The angle between the direction from power transmission device position P S  toward radiation target position P T  and the front direction of power transmission antenna  50 . 
     G: the radiation target position distance. The distance from power transmission device position P S  to radiation target position P T . 
     Gp: the distance from element antenna  8   p  to radiation target position P T . 
     Δp: the difference between Gp and G. Δp=Gp−G. 
     θ G   p : the target position change phase shift amount that is the amount by which element antenna  8  numbered p is changed the phase when power is transmitted to radiation target position P T  having power transmission direction ψ and at distance G. The phase difference between element radio wave  2 E p  radiated by element antenna  8   p  and element radio wave  2 E radiated from power transmission device position P S . 
     k G   p : the phase shift amount for phase shifter  13  numbered p for target position change phase shift amount θ G   p . 
     P E : deviation position. The position different from radiation target position P T . 
     δ: deviation angle. The angle difference between the direction toward deviation position P E  and power transmission direction ψ toward radiation target position P T . The direction toward deviation position P E  is (ψ+δ). 
     D: the deviation position distance. The distance between deviation position P E  and power transmission device position P S . 
     Dp: the deviation position distance. The distance from element antenna  8   p  to deviation position P E . 
     ε G   p : the phase difference between element radio wave  2 E p  radiated by element antenna  8   p  that is detected at deviation position P E  and element radio wave  2 E radiated from power transmission device position P S , in a state of radiation toward radiation target position P T . 
     γ G : the ratio of the amplitude of the electric field vector detected at deviation position P E  to the amplitude of the electric field vector detected at radiation target position P T . Called amplitude attenuation ratio. 
     Distance difference Δp from distance Gp in power transmission direction ψ can be calculated by the following equations. 
     
       
         
           
             
               
                 
                   
                     
                       
                                          
                         
                           GP 
                           = 
                             
                           
                             
                               ( 
                               
                                 
                                   
                                     ( 
                                     
                                       G 
                                       + 
                                       
                                         
                                           ( 
                                           
                                             p 
                                             - 
                                             Nm 
                                           
                                           ) 
                                         
                                         * 
                                         L 
                                         * 
                                         sin 
                                         ⁢ 
                                            
                                         
                                           ( 
                                           ψ 
                                           ) 
                                         
                                       
                                     
                                     ) 
                                   
                                   2 
                                 
                                 + 
                                 
                                   
                                     ( 
                                     
                                       p 
                                       - 
                                       Nm 
                                     
                                     ) 
                                   
                                   * 
                                   L 
                                   * 
                                   
                                     
                                       cos 
                                       ⁡ 
                                       ( 
                                       ψ 
                                       ) 
                                     
                                     2 
                                   
                                 
                               
                               ) 
                             
                           
                         
                       
                     
                   
                   
                     
                       
                         = 
                           
                         
                           
                             ( 
                             
                               
                                 G 
                                 2 
                               
                               + 
                               
                                 2 
                                 * 
                                 G 
                                 * 
                                 sin 
                                 ⁢ 
                                    
                                 
                                   ( 
                                   ψ 
                                   ) 
                                 
                                 * 
                                 
                                   ( 
                                   
                                     p 
                                     - 
                                     Nm 
                                   
                                   ) 
                                 
                                 * 
                                 L 
                               
                               + 
                               
                                 
                                   ( 
                                   
                                     
                                       ( 
                                       
                                         p 
                                         - 
                                         Nm 
                                       
                                       ) 
                                     
                                     * 
                                     L 
                                   
                                   ) 
                                 
                                 2 
                               
                             
                             ) 
                           
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   47 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   
                     
                       
                         
                           Δ 
                           ⁢ 
                           p 
                         
                         = 
                           
                         
                           
                             
                               ( 
                               
                                 
                                   G 
                                   2 
                                 
                                 + 
                                 
                                   2 
                                   * 
                                   G 
                                   * 
                                   sin 
                                   ⁢ 
                                      
                                   
                                     ( 
                                     ψ 
                                     ) 
                                   
                                   * 
                                   
                                     ( 
                                     
                                       p 
                                       - 
                                       Nm 
                                     
                                     ) 
                                   
                                   * 
                                   L 
                                 
                                 + 
                                 
                                   
                                     ( 
                                     
                                       
                                         ( 
                                         
                                           p 
                                           - 
                                           Nm 
                                         
                                         ) 
                                       
                                       * 
                                       L 
                                     
                                     ) 
                                   
                                   2 
                                 
                               
                               ) 
                             
                             - 
                             G 
                           
                         
                       
                     
                   
                   
                     
                       
                         = 
                           
                         
                           
                             
                               ( 
                               
                                 p 
                                 - 
                                 Nm 
                               
                               ) 
                             
                             * 
                             L 
                             * 
                             
                               
                                 ( 
                                 
                                   
                                     2 
                                     * 
                                     G 
                                     * 
                                     sin 
                                     ⁢ 
                                        
                                     
                                       ( 
                                       ψ 
                                       ) 
                                     
                                   
                                   + 
                                   
                                     
                                       ( 
                                       
                                         p 
                                         - 
                                         Nm 
                                       
                                       ) 
                                     
                                     * 
                                     L 
                                   
                                 
                                 ) 
                               
                               / 
                               
                                 ( 
                                 
                                   
                                     G 
                                     ⁢ 
                                     p 
                                   
                                   + 
                                   G 
                                 
                                 ) 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   48 
                   ) 
                 
               
             
           
         
       
     
     According to equation (47), when G is larger to such an extent that (p−Nm)*L can be ignored (G&gt;&gt;(p−Nm)*L), then Gp/G=1 is satisfied, and equation (48) is changed to equation (1). 
     Phase difference θ G   p  can be calculated by the following equation. 
     
       
         
           
             
               
                 
                   
                     
                       
                         
                           θ 
                           p 
                           G 
                         
                         = 
                           
                         
                           
                             ( 
                             
                               2 
                               * 
                               π 
                             
                             ) 
                           
                           * 
                           
                             ( 
                             
                               Δ 
                               ⁢ 
                               
                                 p 
                                 / 
                                 λ 
                               
                             
                             ) 
                           
                         
                       
                     
                   
                   
                     
                       
                         = 
                           
                         
                           
                             ( 
                             
                               2 
                               * 
                               π 
                             
                             ) 
                           
                           * 
                           
                             ( 
                             
                               L 
                               / 
                               λ 
                             
                             ) 
                           
                           * 
                           
                             ( 
                             
                               p 
                               - 
                               Nm 
                             
                             ) 
                           
                         
                       
                     
                   
                   
                     
                       
                           
                         
                           
                             
                               
                                 * 
                                 
                                   
                                     ( 
                                     
                                       
                                         2 
                                         * 
                                         G 
                                         * 
                                         sin 
                                         ⁢ 
                                            
                                         
                                           ( 
                                           ψ 
                                           ) 
                                         
                                       
                                       + 
                                       
                                         
                                           ( 
                                           
                                             p 
                                             - 
                                             Nm 
                                           
                                           ) 
                                         
                                         * 
                                         L 
                                       
                                     
                                     ) 
                                   
                                   / 
                                   
                                     ( 
                                     
                                       
                                         G 
                                         ⁢ 
                                         p 
                                       
                                       + 
                                       G 
                                     
                                     ) 
                                   
                                 
                               
                             
                             
                               
                                 
                                   p 
                                   = 
                                   1 
                                 
                                 , 
                                 … 
                                    
                                 , 
                                 N 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   49 
                   ) 
                 
               
             
           
         
       
     
     Since the phase is changed every θd in phase shifter  13 , k G   p  is determined as follows such that |θ G   p −k G   p *θd|≤(θd/2) is satisfied. 
         k   G   p =int((θ G   p   /θd )+0.5)  (50)
 
       FIG.  53    illustrates an example of the state in which there is a difference between distance Gp from element antenna  8   p  to radiation target position P T  and distance G from power transmission device position P S  to radiation target position P T . Here, N is set to satisfy N=10, and distances G 1 , G 10  from element antennas  8   1 ,  8   10  to radiation target position P T  and distance differences Δ 1 , Δ 10  are illustrated. Power transmission antenna  50  radiates power transmission radio wave  2  from power transmission device position P S  to radiation target position P T . When element antenna  8  is present at power transmission device position P S , element radio wave  2 E Nm  is radiated similarly to power transmission radio wave  2 . Element radio wave  2 E p  radiated by element antenna  8   p  is radiated with the phase adjusted so as to have a phase difference k G   p *θd corresponding to distance difference Δ n  in comparison to power transmission radio wave  2 . By doing so, the phase difference between element radio waves  2 E p  radiated by element antennas  8   p  at radiation target position P T  is equal to or less than (θd/2). 
     The phase difference ε G   p  between element radio wave  2 E p  radiated by element antenna  8   p  and element radio wave  2 E radiated from power transmission device position P S  as detected at deviation position P E  is determined as follows. 
     
       
         
           
             
               
                 
                   
                     
                       
                         
                           ε 
                           p 
                           G 
                         
                         = 
                           
                         
                           
                             
                               ( 
                               
                                 2 
                                 * 
                                 π 
                               
                               ) 
                             
                             * 
                             
                               ( 
                               
                                 
                                   ( 
                                   
                                     
                                       D 
                                       ⁢ 
                                       p 
                                     
                                     - 
                                     D 
                                   
                                   ) 
                                 
                                 / 
                                 λ 
                               
                               ) 
                             
                           
                           - 
                           
                             
                               k 
                               G 
                             
                             ⁢ 
                             p 
                             * 
                             θ 
                             ⁢ 
                             d 
                           
                         
                       
                     
                   
                   
                     
                       
                         = 
                           
                         
                           
                             ( 
                             
                               2 
                               * 
                               π 
                             
                             ) 
                           
                           * 
                           
                             ( 
                             
                               L 
                               / 
                               λ 
                             
                             ) 
                           
                           * 
                           
                             ( 
                             
                               p 
                               - 
                               
                                 N 
                                 ⁢ 
                                 m 
                               
                             
                             ) 
                           
                         
                       
                     
                   
                   
                     
                       
                           
                         
                           
                             * 
                             
                               
                                 ( 
                                 
                                   
                                     2 
                                     * 
                                     D 
                                     * 
                                        
                                     sin 
                                     ⁢ 
                                        
                                     
                                       ( 
                                       
                                         ψ 
                                         + 
                                         δ 
                                       
                                       ) 
                                     
                                   
                                   + 
                                   
                                     
                                       ( 
                                       
                                         p 
                                         - 
                                         Nm 
                                       
                                       ) 
                                     
                                     * 
                                     L 
                                   
                                 
                                 ) 
                               
                               / 
                               
                                 ( 
                                 
                                   
                                     D 
                                     ⁢ 
                                     p 
                                   
                                   + 
                                   D 
                                 
                                 ) 
                               
                             
                           
                           - 
                           
                             
                               k 
                               G 
                             
                             ⁢ 
                             p 
                             * 
                             θ 
                             ⁢ 
                             d 
                           
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   51 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   Dp 
                   = 
                   
                     
                       ( 
                       
                         
                           D 
                           2 
                         
                         + 
                         
                           2 
                           * 
                           D 
                           * 
                           sin 
                           ⁢ 
                              
                           
                             ( 
                             
                               ψ 
                               + 
                               δ 
                             
                             ) 
                           
                           * 
                           
                             ( 
                             
                               p 
                               - 
                               Nm 
                             
                             ) 
                           
                           * 
                           L 
                         
                         + 
                         
                           
                             ( 
                             
                               
                                 ( 
                                 
                                   p 
                                   - 
                                   Nm 
                                 
                                 ) 
                               
                               * 
                               L 
                             
                             ) 
                           
                           2 
                         
                       
                       ) 
                     
                   
                 
               
               
                 
                   ( 
                   52 
                   ) 
                 
               
             
           
         
       
     
     Assuming that δ is minute, equations (51) and (52) are approximated by sin(δ)≈δ and cos(δ)≈1 as follows. 
     
       
         
           
             
               
                 
                   
                     
                       
                         
                           ε 
                           p 
                           G 
                         
                         = 
                           
                         
                           
                             ( 
                             
                               2 
                               * 
                               π 
                             
                             ) 
                           
                           * 
                           
                             ( 
                             
                               L 
                               / 
                               λ 
                             
                             ) 
                           
                           * 
                           
                             ( 
                             
                               p 
                               - 
                               
                                 N 
                                 ⁢ 
                                 m 
                               
                             
                             ) 
                           
                         
                       
                     
                   
                   
                     
                       
                           
                         
                           * 
                           
                             
                               ( 
                               
                                 
                                   2 
                                   * 
                                   D 
                                   * 
                                   δ 
                                   * 
                                   cos 
                                   ⁢ 
                                      
                                   
                                     ( 
                                     ψ 
                                     ) 
                                   
                                 
                                 + 
                                 
                                   
                                     ( 
                                     
                                       p 
                                       - 
                                       Nm 
                                     
                                     ) 
                                   
                                   * 
                                   L 
                                 
                               
                               ) 
                             
                             / 
                             
                               ( 
                               
                                 
                                   D 
                                   ⁢ 
                                   p 
                                 
                                 + 
                                 D 
                               
                               ) 
                             
                           
                         
                       
                     
                   
                   
                     
                       
                           
                         
                           
                             - 
                             
                               k 
                               G 
                             
                           
                           ⁢ 
                           p 
                           * 
                           θ 
                           ⁢ 
                           d 
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   53 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   Dp 
                   = 
                   
                     ( 
                     
                       
                         D 
                         2 
                       
                       + 
                       
                         2 
                         * 
                         D 
                         * 
                         δ 
                         * 
                         cos 
                         ⁢ 
                            
                         
                           ( 
                           ψ 
                           ) 
                         
                         * 
                         
                           ( 
                           
                             p 
                             - 
                             Nm 
                           
                           ) 
                         
                         * 
                         L 
                       
                       + 
                       
                         
                           ( 
                           
                             
                               ( 
                               
                                 p 
                                 - 
                                 Nm 
                               
                               ) 
                             
                             * 
                             L 
                           
                           ) 
                         
                         2 
                       
                     
                     ) 
                   
                 
               
               
                 
                   ( 
                   54 
                   ) 
                 
               
             
           
         
       
     
     The amplitude attenuation ratio γ G , which is a value obtained by diving the amplitude of the electric field vector detected at deviation position P E  by the amplitude of the electric field vector detected at radiation target position P T  can be calculated as follows. The deterioration of power transmission efficiency caused by changing the phase every θd in phase shifter  13  is ignored at radiation target position P T . 
       γ G =(1/ N )*Σexp( j*ε   G   p )  (55)
 
     In equation (55) and the like, Σ means summation with p=1, . . . , N. Based on equation (55), the absolute value |γ G | of γ G  can be calculated as follows. 
       |γ G |=(1/ N )*√(Σ cos(ε G   p )) 2 +(Σ sin(ε G   p )) 2 )  (56)
 
     A case where power transmission antenna  50  is a phased array antenna where N=10, f=5 GHz, λ=60 mm, L=1800 mm=1.8 m, nd=128, and θd=2.8125 degrees are satisfied is studied.  FIG.  54    illustrates graphs representing change of amplitude attenuation ratio γ to change of deviation angle δ while satisfying G=1000 m, in a case where the positions in power transmission directions ψ=0 degrees, 30 degrees, and 60 degrees are the radiation target position satisfying G=1000 m.  FIG.  54 (A)  illustrates δ in the range from 10 degrees to −10 degrees, and  FIG.  54 (B)  illustrates a magnification of δ in the range from 5 degrees to −5 degrees.  FIG.  55    illustrates graphs representing change of amplitude attenuation ratio γ when distance G is changed while ψ=0 degrees, 30 degrees, or 60 degrees is satisfied. In  FIG.  55   , the horizontal axis is indicated by log 10 (D/G). When D=G is satisfied, log 10 (D/G) is zero. In  FIG.  54    and  FIG.  55   , the graph for ψ=0 degrees is satisfied is depicted by a solid line, the graph satisfying ψ=30 degrees is depicted by a broken line, and the graph satisfying ψ=60 degrees is depicted by a long and short dashed line. 
     When ψ=0 degrees is satisfied in  FIG.  54   , the half-width (full width at half maximum) at which the amplitude of the electric field vector attenuates to half is approximately 0.24 degrees. In the case of  FIG.  6    in which a far field is established, the half-width is approximately 6.8 degrees. When a power transmission radio wave is radiated when ψ=0 degrees is satisfied, the half-width of the power transmission beam is reduced to approximately 1/28 in  FIG.  54   , compared with  FIG.  6   . The half-width of the power transmission beam becomes narrower substantially in proportion to the size of power transmission antenna  50 J approximately 30 times larger. The half-width when ψ=30 degrees is satisfied is substantially the same as when ψ=0 degrees is satisfied. When ψ=60 degrees is satisfied, the half-width is approximately 0.47 degrees. When ψ=0 degrees is satisfied, the amplitude of the electric field vector takes peaks at intervals of about 1.9 degrees, and when ψ=30 degrees is satisfied, peaks are taken at intervals of approximately 2.2 degrees. When ψ=60 degrees is satisfied, peaks are taken approximately at 3.6 degrees in the amplitude of the electric vector on the side where deviation angle δ&lt;0 is satisfied and at approximately 4.0 degrees on the side where deviation angle δ&gt;0 is satisfied. 
     When the phase of a power transmission beam is controlled also in consideration of the radiation target position, the variation of amplitude attenuation ratio γ is large relative to the variation of deviation distance D. When ψ=0 degrees is satisfied in  FIG.  55   , amplitude attenuation ratio γ is decreased 3 dB at log 10 (D/G)≈0.28, that is, D≈0.53*G. On the increasing side of deviation distance D, γ is decreased 3 dB at log 10 (D/G)≈1.03, that is, D≈10.7*G. When ψ=30 degrees is satisfied, γ is decreased 3 dB at log 10 (D/G)≈−0.34, that is, D≈0.45*G. When ψ=60 degrees is satisfied, γ is decreased 3 dB at log 10 (D/G)≈−0.67, that is, D≈0.21*G. On the increasing side of deviation distance D, when ψ=30 degrees is satisfied, γ is decreased approximately 1.8 dB at log 10 (D/G)≈, that is, D≈10*G. When ψ=60 degrees is satisfied, γ is decreased approximately 0.2 dB at log 10 (D/G)=, that is, D=10*G. When the beam width is large, the degree of decrease of γ to variation of the distance is small. 
       FIG.  56    and  FIG.  57    illustrate graphs of amplitude attenuation ratio γ when only L is changed to L=600 mm as a comparative example.  FIG.  56    illustrates graphs representing change of amplitude attenuation ratio γ to change of deviation angle δ for a transmission antenna satisfying L=600 mm.  FIG.  57    illustrates graphs representing change of amplitude attenuation ratio γ to change of deviation distance D for a transmission antenna satisfying L=600 mm. In  FIG.  56   , the half-width satisfying ψ=0 degrees is approximately 0.71 degrees. When ψ=30 degrees is satisfied, the half-width is approximately 0.82 degrees, and when ψ=30 degrees is satisfied, the half-width is approximately 1.4 degrees. Since the size of power transmission antenna  50  is ⅓ times smaller, the half-width is approximately three times larger. The interval between peaks is larger for each angle of ψ. When ψ=0 degrees is satisfied, peaks are taken at an interval of approximately 5.7 degrees, and when ψ=30 degrees is satisfied, peaks are taken at an interval of approximately 6.4 degrees. When ψ=60 degrees is satisfied, peaks are taken at approximately 10 degrees on the side where deviation angle δ&lt;0 is satisfied, and the interval of peaks is greater than 10 degrees on the side where δ&gt;0 is satisfied. 
     In the change of amplitude attenuation ratio γ to change of deviation distance D illustrated in  FIG.  57   , decrease of γ is less than 0.4 dB with any angle ψ in the range of log 10 (D/G)&gt;−0.5, that is, D&gt;0.32*G. It can be thought that for power transmission antenna  50  satisfying L=600 min, power transmission distance G=1000 m is the distance at which a far field is established. When ψ=0 degrees is satisfied, γ is decreased 3 dB at log 10 (D/G)≈−0.96, that is, D≈0.11*G. When ψ=30 degrees is satisfied, log 10 (D/G)=−1.07, that is, D≈0.085*G. When ψ=60 degrees is satisfied, at log 10 (D/G)=−1.25, that is, D≈0.056*G, the decrease of γ is approximately 0.8 dB. 
       FIG.  57    can be considered as the graphs illustrating how much the power transmission efficiency is decreased at a closer distance in wireless power transmission device  1  controlling such that the phase of each element radio wave  2 E is matched at a distance of a far field. From  FIG.  57   , it can be understood that the power transmission efficiency is decreased in wireless power transmission device  1  when movable body  60  is present at a nearer position. In wireless power transmission device  1 J, the phase of each element radio wave  2 E p  is controlled such that the amplitude of power transmission radio wave  2  is maximized at the radiation target position also in consideration of distance G to the movable body, whereby the amplitude of the power transmission radio wave can be maintained at the maximum for any value of distance G. Even when the movable body such as a drone equipped with the power reception device moves in the depth direction viewed from the wireless power transmission device, the phase of a radio wave radiated by each element antenna included in the phased array antenna can be set to the optimum value, thereby improving the power transmission efficiency. 
     The effect of the power transmission beam tracking movable body  60  using the position of movable body  60  as radiation target position P T  during execution of the REV method is studied. For distance G to movable body  60  and power transmission direction ψ, the values calculated by equation (9) and equation (10) is measured. The variables used for explaining the process of the REV method are defined as follows. The variables already defined are also used. 
     P T   t : the position of movable body  60  at elapsed time t since the start of the REV method. 
     θ G   rp : the phase command value for phase shifter  13  numbered q during execution of the REV method. 
     E G   p : the element electric field vector at radiation target position P T  generated by element radio wave  2 E p  radiated by element antenna  8   p  numbered p. 
     E G sum: the electric field vector at radiation target position P T  generated by element radio waves  2 E radiated by all element antennas  8 . 
     θ G sum: the phase of electric field vector E G sum. 
     In the REV method, the phase is changed by r*θd every time Td in the order of r=1, . . . nd in element antenna  8  numbered q in the order of q=1, . . . , N. Further, the phase of element radio wave  2 E p  radiated by each element antenna  8   p  is controlled so that element radio wave  2 E can be radiated toward radiation target position P T . Phase command value θ G   rp  for each phase shifter  13  at time t=m*Td is determined as follows. k G   p *θd in equation (57-1) and equation (57-2) is the target position change phase shift amount, and r*θd is the operation phase shift amount. k G   p  can be calculated from equation (50) and equation (49). 
       For  p  satisfying  p≠q, θ   G   rp   =k   G   p   *θd   (57-1)
 
       For  p  satisfying  p=q, θ   G   rp =( k   G   p   +r )*θ d   (57-2)
 
     Here, the relation of q and r with m is written by equations (12) and (13). 
     The phase of element radio wave  2 E p  radiated by element antenna  8   p  numbered p has the following three kinds of differences with respect to target position change phase shift amount θ G   p . 
     (A) the phase error φp of element radio wave  2 E p  radiated by element antenna  8   p  numbered p. 
     (B) the error of approximating θ G p by an integer multiple of θd. 
     (C) the operation phase shift amount r* 0   d  in executing the REV method. 
     The element electric field vectors E G   p  and E G sum therefore can be calculated as follows. 
     
       
         
           
             
               
                 
                   
                     E 
                     p 
                     G 
                   
                   = 
                   
                     
                       E 
                       0 
                     
                     * 
                     exp 
                     ⁢ 
                        
                     
                       ( 
                       
                         j 
                         ⁡ 
                         ( 
                         
                           
                             φ 
                             ⁢ 
                             p 
                           
                           + 
                           
                             θ 
                             rp 
                             G 
                           
                           - 
                           
                             θ 
                             p 
                             G 
                           
                         
                         ) 
                       
                       ) 
                     
                   
                 
               
               
                 
                   ( 
                   58 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   
                     
                       E 
                       G 
                     
                     ⁢ 
                        
                     sum 
                   
                   = 
                   
                     
                       Σ 
                       ⁢ 
                       
                         E 
                         p 
                         G 
                       
                     
                     = 
                     
                       
                         E 
                         0 
                       
                       * 
                       Σ 
                       ⁢ 
                          
                       exp 
                       ⁢ 
                          
                       
                         ( 
                         
                           j 
                           ⁡ 
                           ( 
                           
                             
                               φ 
                               ⁢ 
                               p 
                             
                             + 
                             
                               θ 
                               rp 
                               G 
                             
                             - 
                             
                               θ 
                               p 
                               G 
                             
                           
                           ) 
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   59 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   
                     
                       
                         
                           
                             ❘ 
                             &#34;\[LeftBracketingBar]&#34; 
                           
                           
                             
                               E 
                               G 
                             
                             ⁢ 
                                
                             sum 
                           
                           
                             ❘ 
                             &#34;\[RightBracketingBar]&#34; 
                           
                         
                         = 
                           
                         
                           
                             ( 
                             
                               
                                 ( 
                                 
                                   Σ 
                                   ⁢ 
                                      
                                   cos 
                                   ⁢ 
                                      
                                   
                                     ( 
                                     
                                       
                                         φ 
                                         ⁢ 
                                         p 
                                       
                                       + 
                                       
                                         θ 
                                         
                                           r 
                                           ⁢ 
                                           p 
                                         
                                         G 
                                       
                                       - 
                                       
                                         θ 
                                         p 
                                         G 
                                       
                                     
                                     ) 
                                   
                                 
                                 ) 
                               
                               2 
                             
                           
                         
                       
                     
                   
                   
                     
                       
                         
                           + 
                             
                           
                             
                               ( 
                               
                                 Σ 
                                 ⁢ 
                                    
                                 sin 
                                 ⁢ 
                                    
                                 
                                   ( 
                                   
                                     
                                       φ 
                                       ⁢ 
                                       p 
                                     
                                     + 
                                     
                                       θ 
                                       rp 
                                       G 
                                     
                                     - 
                                     
                                       θ 
                                       p 
                                       G 
                                     
                                   
                                   ) 
                                 
                               
                               ) 
                             
                             2 
                           
                         
                         ) 
                       
                     
                   
                 
               
               
                 
                   ( 
                   60 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   
                     
                       θ 
                       G 
                     
                     ⁢ 
                        
                     sum 
                   
                   = 
                   
                     
                       sin 
                       
                         - 
                         1 
                       
                     
                     ( 
                     
                       Σ 
                       ⁢ 
                          
                       sin 
                       ⁢ 
                          
                       
                         
                           ( 
                           
                             
                               φ 
                               ⁢ 
                               p 
                             
                             + 
                             
                               θ 
                               rp 
                               G 
                             
                             - 
                             
                               θ 
                               p 
                               G 
                             
                           
                           ) 
                         
                         / 
                         
                           
                             ❘ 
                             &#34;\[LeftBracketingBar]&#34; 
                           
                           
                             
                               E 
                               G 
                             
                             ⁢ 
                                
                             sum 
                           
                           
                             ❘ 
                             &#34;\[RightBracketingBar]&#34; 
                           
                         
                       
                     
                     ) 
                   
                 
               
               
                 
                   ( 
                   61 
                   ) 
                 
               
             
           
         
       
     
     A comparative example in which movable body  60  is not tracked during execution of the REV method is studied. The following variables are defined. 
     P T   0 : the position of movable body  60  at the start of the REV method (t=0). 
     ψ 0 : the radiation direction at the start of the REV method. The angle between the direction from power transmission device position P S  toward radiation target position P T   0  and the front direction of power transmission antenna  50 . 
     G 0 : the radiation target position distance at the start of the REV method. The distance from power transmission device position P S  to radiation target position P T   0 . 
     G 0p : the distance from element antenna  8   p  to radiation target position P T   0  at the start of the REV method. 
     Δ 0p : the difference between G 0p  and G 0 . Δ 0p =G 0p −G 0 . 
     θ G   0p : the target position change phase shift amount for element antenna  8  numbered p when element radio wave  2 E p  is radiated toward radiation target position P T   0  at the start of the REV method. 
     k G   0p : the phase shift amount for phase shifter  13  numbered p for target position change phase shift amount θ G   0p . 
     ε2 G   p : the phase difference between element radio wave  2 E p  radiated by element antenna  8   p  detected at P T  (corresponding to the deviation position) of movable body  60  and element radio wave  2 E radiated from power transmission device position P S , in a state of radiation toward radiation target position P T   0  during execution of the REV method. 
     E2 G   p : the element electric field vector generated by element radio wave  2 E p  radiated by element antenna  8   p  numbered p at position P T  of movable body  60 , in a state of radiation toward radiation target position P T   0  during execution of the REV method. 
     E2 G sum: the electric field vector generated by element radio waves  2 E radiated by all element antennas  8  at position P T  of movable body  60 , in a state of radiation toward radiation target position P T   0  during execution of the REV method. 
     θ2 G sum: the phase of electric field vector E2 G sum. 
     θ G   0p , k G   0p , and ε2 G   p  can be calculated as follows. 
       θ G   0p =(2*π)*( L /λ)*( p−Nm )*(2* G   0 *sin(ψ 0 )+( p−Nm )* L )/( G   0p   +G   0 )  (62)
 
         k   G   0p =int((θ G   0p   /θd )+0.5)  (63)
 
       ε2 G   p =(2*π)*(( Gp−G )/λ)− k   G   0   p*θd =(2*π)*( L /λ)*( p−Nm )*(2* G *sin(ψ)+( p−Nm )* L )/( Gp+G )− k   6   0   p*θd   (64)
 
     Equation (7) is substituted into equation (64) as follows. 
       ε2 G   p =(2*π)*( L /λ)*( p−Nm )/( Gp+G )*(2*( G   0 *sin(ψ 0 )+ V   0   *m*Td *sin(ξ 0 ))+( p−Nm )* L )− k   G   0   p*θd   (65)
 
     When movable body  60  is not tracked during execution of the REV method, the phase command value θ G   rp  for each phase shifter  13  at time t=m*Td is determined as follows. 
       For  p  satisfying  p≠q, θ   G   rp   =k   G   0p   *θd   (66-1)
 
       For  p  satisfying  p=q, θ   G   rp =( k   G   0p   +r )*θ d   (66-2)
 
     E2 G   p  and E2 G sum can be calculated by the following equations. 
     
       
         
           
             
               
                 
                   
                     E 
                     ⁢ 
                     
                       2 
                       p 
                       G 
                     
                   
                   = 
                   
                     
                       E 
                       0 
                     
                     * 
                     exp 
                     ⁢ 
                        
                     
                       ( 
                       
                         j 
                         ⁡ 
                         ( 
                         
                           
                             φ 
                             ⁢ 
                             p 
                           
                           + 
                           
                             θ 
                             rp 
                             G 
                           
                           - 
                           
                             θ 
                             
                               0 
                               ⁢ 
                               p 
                             
                             G 
                           
                           + 
                           
                             ε2 
                             p 
                             G 
                           
                         
                         ) 
                       
                     
                   
                 
               
               
                 
                   ( 
                   67 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   
                     
                       
                         
                           E 
                           ⁢ 
                           2 
                           ⁢ 
                              
                           sum 
                         
                         = 
                           
                         
                           Σ 
                           ⁢ 
                           
                             E2 
                             p 
                           
                         
                       
                     
                   
                   
                     
                       
                         = 
                           
                         
                           
                             E 
                             0 
                           
                           * 
                           Σ 
                           ⁢ 
                              
                           exp 
                           ⁢ 
                              
                           
                             ( 
                             
                               j 
                               ⁡ 
                               ( 
                               
                                 
                                   φ 
                                   ⁢ 
                                   p 
                                 
                                 + 
                                 
                                   θ 
                                   rp 
                                   G 
                                 
                                 - 
                                 
                                   θ 
                                   
                                     0 
                                     ⁢ 
                                     p 
                                   
                                   G 
                                 
                                 + 
                                 
                                   ε2 
                                   p 
                                   G 
                                 
                               
                               ) 
                             
                           
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   68 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   
                     
                       
                         
                           
                             ❘ 
                             &#34;\[LeftBracketingBar]&#34; 
                           
                           
                             E 
                             ⁢ 
                             2 
                             ⁢ 
                                
                             sum 
                           
                           
                             ❘ 
                             &#34;\[RightBracketingBar]&#34; 
                           
                         
                         = 
                           
                         
                           
                             ( 
                             
                               
                                 ( 
                                 
                                   Σ 
                                   ⁢ 
                                      
                                   cos 
                                   ⁢ 
                                      
                                   
                                     ( 
                                     
                                       
                                         φ 
                                         ⁢ 
                                         p 
                                       
                                       + 
                                       
                                         θ 
                                         
                                           r 
                                           ⁢ 
                                           p 
                                         
                                         G 
                                       
                                       - 
                                       
                                         θ 
                                         
                                           0 
                                           ⁢ 
                                           p 
                                         
                                         G 
                                       
                                       + 
                                       
                                         ε2 
                                         p 
                                         G 
                                       
                                     
                                     ) 
                                   
                                 
                                 ) 
                               
                               2 
                             
                           
                         
                       
                     
                   
                   
                     
                       
                           
                         
                           + 
                           
                             
                               ( 
                               
                                 Σ 
                                 ⁢ 
                                    
                                 sin 
                                 ⁢ 
                                    
                                 
                                   ( 
                                   
                                     
                                       φ 
                                       ⁢ 
                                       p 
                                     
                                     + 
                                     
                                       θ 
                                       rp 
                                       G 
                                     
                                     - 
                                     
                                       θ 
                                       
                                         0 
                                         ⁢ 
                                         p 
                                       
                                       G 
                                     
                                     + 
                                     
                                       ε2 
                                       p 
                                       G 
                                     
                                   
                                   ) 
                                 
                               
                               ) 
                             
                             2 
                           
                         
                         ) 
                       
                     
                   
                 
               
               
                 
                   ( 
                   69 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   
                     
                       
                         
                           θ2 
                           ⁢ 
                              
                           sum 
                         
                         = 
                           
                         
                           
                             sin 
                             
                               - 
                               1 
                             
                           
                           ( 
                           
                             Σ 
                             ⁢ 
                                
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     As another comparative example, a case where phase θp of each phase shifter  13   p  is controlled such that only the radiation direction of radio wave  2  is changed as in wireless power transmission device  1  and the power transmission beam tracks movable body  60  during execution of the REV method is studied. Direction change phase shift amount θ p  can be calculated by the above equation (1). k p  that discretizes θ p  can be calculated by equation (2). Phase command value θ rp  for each phase shifter  13  during execution of the REV method can be calculated by the above equation (11-1) and equation (11-2). 
     In phase shifter  13   p , although phase difference θ G   p  calculated by equation (49) should be generated, direction change phase shift amount θ p  calculated in equation (1) is set. Therefore, element electric field vector E p  is determined as follows. θ p  is used for calculating θ rp . 
         E   p   =E   0 *exp( j (φ p+θ   rp −θ G   p ))  (71)
 
     Esum and θ sum  can be calculated as follows. 
         E sum=Σ E   p   =E   0 *Σexp( j (φ p+θ   rp −θ G   p )  (72)
 
       | E sum|=√((Σ cos(φ p+θ   rp −θ G   p )) 2 +(Σ sin(φ p+θ   rp −θ G   p )) 2 )  (73)
 
       θsum=sin −1 (Σ sin(φ p+θ   rp −θ G   p )/| E sum|)  (74)
 
     Equation (31) to equation (32) for distance G and the orientation direction (ψ AZ , ψ EL ) for the power transmission antenna having element antennas  8  arranged in two dimensions to track movable body  60  are satisfied similarly in the tenth embodiment. 
     The following variables are defined to represent the target position change phase shift amount in the power transmission antenna having element antennas  8  arranged in dimensions. 
     θ G   xp,yp : the target position change phase shift amount for element antenna  8  numbered (xp, yp) when power transmission radio wave  2  is radiated toward the radiation target position at distance G and in the power transmission direction (ψ AZ , ψ EL ). 
     k G   xp,yp : the phase shift amount for phase shifter  13  numbered (xp, yp) for target position change phase shift amount θ G   xp,yp . 
     θ G   xp,yp  and k G   xp,yp  can be calculated by the following equations. 
     
       
         
           
             
               
                 
                   
                     
                       
                         
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       FIG.  58    and  FIG.  59    illustrate an example in which wireless power transmission device  1 J sets radiation target position P T  in accordance with the position of moving movable body  60 . In  FIG.  58   , movable body  60  moves such that the arrival direction is changed mainly. In  FIG.  59   , movable body  60  moves such that the distance from wireless power transmission device  1 J is changed mainly. No matter how movable body  60  moves, wireless power transmission device  1 J obtains the position of movable body  60  and sets radiation target position P T  such that the obtained position is included. Wireless power transmission device  1 J controls each element module  9  to radiate power transmission radio wave  2  such that the maximum power at radiation target position P T  can be transmitted. 
     The operation is described.  FIG.  60    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the tenth embodiment. In  FIG.  60   , points different from  FIG.  8    in the first embodiment are described. 
     At step S 01 J, wireless power transmission device  1 J radiates power transmission radio wave  2 J, using the position at distance G and in the power transmission direction (ψ AZ , ψ EL ) where movable body  60 J is present as the radiation target position. Power reception device  3  included in movable body  60 J receives power transmission radio wave  2 J. The process of executing the REV method at S 06 J is also changed slightly. 
     The process of determining a power transmission direction at S 11  to S 13  is changed to the process of determining a radiation target position at steps S 81  to S 85 . At step S 81 , distance meter  46  starts pulse modulation of power transmission radio wave  2 J and records pulse transmission time  95 . The length of period TO of pulse modulation is predetermined, and distance meter  46  records the start time and the end time of the period of pulse modulation as pulse transmission time  95 . At step S 82 , movable body  60 J receives pulse-modulated power transmission radio wave  2 J and pulse-modulates pilot signal  4 J at a time when T 1  elapses from the reception of pulse-modulated power transmission radio wave  2 J. When reception of pulse-modulated power transmission radio wave  2 J is stopped, pilot signal  4 J is not pulse-modulated at a time when T 1  elapses. 
     At step S 83 , pilot antenna  6  receives pilot signal  4 J, and arrival direction detecting device  7 J detects the arrival direction of pilot signal  4 J by mono-pulse angle measurement. Arrival direction detecting device  7 J checks whether pilot signal  4 J is pulse-modulated and sends pulse modulation detection signal  89  to control device  10 J at the moment when pulse modulation is detected and at the moment when the end of pulse modulation is detected. 
     At step S 84 , when control device  10 J receives pulse modulation detection signal  89  for the start, distance meter  46  sets the time of that moment in pulse reception time  96 . When pulse modulation detection signal  89  for the end is received, distance meter  46  also sets the time of that moment in pulse reception time  96 . Distance meter  46  determines target position distance G from time difference T 3  between pulse reception time  96  and pulse transmission time  95  to set target position distance data  97 . The arrival direction detected by arrival direction detecting device  7 J is set in arrival direction data  78 . 
     At step S 85 , radiation target position determiner  47  determines the radiation target position based on arrival direction data  78  and target position distance data  97  and sets the determined radiation target position in radiation target position data  94 . At S 01 J, wireless power transmission device  1 J radiates power transmission radio wave  2 J toward the position specified by radiation target position data  95  set at S 85 . 
     After S 85  is performed, the process returns to S 81 . The process at S 81  to S 85  is performed periodically in predetermined cycles. The length of one cycle is determined such that the difference between the radiation target position calculated last time and the current radiation target position is within an acceptable range even when movable body  60 J moves at the possible maximum moving speed. 
     Referring to  FIG.  61   , the procedure of executing the REV method at S 06 J is described.  FIG.  61    is a flowchart illustrating the procedure of calculating an element electric field vector of a radio wave radiated by each element antenna by the REV method in the wireless power transmission device according to the tenth embodiment. In  FIG.  61   , points different from  FIG.  9    in the first embodiment are described. 
     At S 33 J, only the target position change phase shift amount is set as the phase shift amount of phase shifter  13 , instead of the direction change phase shift amount. 
     The effect of a power transmission beam tracking movable body  60 J during execution of the REV method by wireless power transmission device  1 J is explained with an operation example. A case where the parameters of the power transmission antenna and the REV method are N=10, f=5 GHz, λ=60 mm. L=1800 mm=1.8 m, nd=128, θd=2.8125 degrees is studied. The parameters for movable body  60 J are G 0 =1000 m, ψ 0 =30 degrees, V 0 =−30 m/sec, and ξ 0 =90 degrees. Compared with the first embodiment, L=1800 mm and ψ 0 =30 degrees are changed. 
       FIG.  62    is a diagram illustrating phase offset values and phase errors remaining after correction obtained in the wireless power transmission device according to the tenth embodiment and comparative examples, in the operation example in which L=1800 mm is satisfied. The comparative examples include a case where the power transmission beam does not track the movable body (without movement correction) during execution of the REV method and a case where the movable body is tracked (with direction correction) during execution of the REV method in wireless power transmission device  1  radiating a power transmission radio wave toward the power transmission direction.  FIG.  62 (A)  illustrates the set phase error and the phase offset value obtained by executing the REV method, and  FIG.  62 (B)  illustrates the remaining phase error. The setting value of the phase error is depicted by a thin solid line, the phase offset value obtained when the radiation target position tracks the movable body (with movement correction) during execution of the REV method is depicted by a thick solid line, the phase offset value obtained when the radiation target position does not track the movable body (without movement correction) is depicted by a thick broken line, and the phase offset value obtained when the power transmission direction tracks the movable body (with direction correction) is depicted by a thin broken line.  FIG.  62 (B)  illustrates the remaining phase error obtained by subtracting the phase offset value from the set phase error. In  FIG.  62   , the average value of the phase offset value for each phase shifter  13   p  and the average value of the remaining phase error are zero. 
     The phase offset value with movement correction is calculated such that the absolute value of the difference from the set phase error φp is approximately 9 degrees at maximum and approximately 5 degrees on average. The absolute value of the difference of phase offset value without movement correction from φp is approximately 128 degrees at maximum and approximately 56 degrees on average. The difference of the phase offset value with direction correction from φp is larger at p=1 and p=10 at both ends of power transmission antenna  50 . The absolute value of the difference from φp is approximately 89 degrees at maximum and approximately 48 degrees on average. 
       FIG.  63    is a diagram comparing the absolute values of the amplitude of the composite electric field vector after correction in the wireless power transmission device according to the first embodiment and the comparative example in an operation example in which L=1800 mm is satisfied. When the phase of element radio wave  2 E p  radiated by each element antenna  8   p  is matched, |E 6 sum|=10 is obtained. |E G sum| is decreased to |E G sum|=8.6 before execution of the REV method. In the REV method with movement correction, |E G sum|=9.95 is obtained after correction. In the REV method without movement correction, |E2 G sum|=4.8 is obtained after correction. In the REV method with direction correction, |Esum|=6.2 is obtained after correction. Without movement correction and with direction correction, the amplitude of the composite electric field vector after correction is smaller than before execution of the REV method. 
     It can be understood that the power transmission direction tracks the movable body during execution of the REV method whereby the phase error can be eliminated accurately by the REV method. When the radiation target position does not track the movable body during execution of the REV method, the REV method fails to correct the phase error. It can be thought that in a case in which L=1800 mm and G=1000 m are satisfied, the radio wave radiated by power transmission antenna  50  is unable to be calculated by the formula for a far field. With the distance at which the electric field is unable to be calculated by the formula for a far field, the REV method fails to correct the phase error when only the power transmission direction to the movable body is changed. 
       FIG.  64    and  FIG.  65    illustrate the result obtained when the REV method is executed in another example in which L=600 m is satisfied. The phase offset value with movement correction is calculated such that the absolute value of the difference from the set phase error φp is approximately 7.4 degrees at maximum and approximately 4.1 degrees on average. The absolute value of the difference of the phase offset value with direction correction from φp is approximately 9.8 degrees at maximum and approximately 5.2 degrees on average. As illustrated in  FIG.  65   , in a case satisfying L=600 mm, the amplitude of the composite electric field vector |Esum| is 9.97 with direction correction. When L=600 mm at which G=1000 m is thought to be a far field, the REV method can correct the phase error even when the REV method to correct only the direction is executed. 
     Wireless power transmission device  1 J operates similarly to wireless power transmission device  1  and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. Since the phase of element radio wave  2 E p  radiated by each element antenna  8   p  is controlled also in consideration of the distance to movable body  60 , the power transmission efficiency can be higher than when the phase is controlled such that only the radiation direction tracks the movable body when power transmission antenna  50  is large or the distance to movable body  60  is small. 
       FIG.  62    to  FIG.  65    illustrate an example of phase error φp. Although not illustrated in the drawings, wireless power transmission device  1 J can execute REV method accurately even when phase error φp has any other pattern, similarly to wireless power transmission device  1 . 
     Referring to  FIG.  66   , the amplitude of the composite electric field vector obtained by executing the REV method is studied, where distance L between element antennas  8  which is an indicator of the size of power transmission antenna  50  is changed satisfying G=1000 m, with several power transmission directions ψ 0 .  FIG.  66    illustrates graphs indicating the amplitude of the composite electric field vector |E G sum| obtained by executing the REV method obtained by executing the REV method with changing L when the power transmission direction ψ 0  is one of 30 degrees, 0 degrees, and 90 degrees at the start of the REV method. Here, the basic pattern of parameters for movement of movable body  60 J are G 0 =1000 m, ψ 0 =30 degrees, V 0 =−30 m/sec, and ξ 0 =90 degrees. The parameters that are not changed in the drawings take the values of the basic pattern. The horizontal axis in the graph in  FIG.  66    and the like shows a value (log 10 (L/λ)) represented by the common logarithm of the rate of L to wavelength λ. 
     The amplitude of the composite electric field vector |E G   sum | obtained by performing the REV method with the radiation target position tracking movable body  60  is depicted by a thick solid line. The amplitude of the composite electric field vector |E2 G   sum | obtained by executing the REV method with a power transmission beam fixed at the position of movable body  60  at the start of the REV method as the radiation target position is depicted by a broken line. The amplitude of the composite electric field vector |E sum | obtained by performing the REV method with only the radiation direction of a power transmission beam tracking the movable body is depicted by a long and short dashed line. These depictions are similar in other graphs. 
     |E2 G   sum | obtained when ψ 0 =30 degrees is satisfied is depicted by a thick broken line, |E2 G   sum | obtained when ψ 0 =0 degrees is satisfied is depicted by a broken line with an intermediate thickness, and |E2 G   sum | obtained when ψ 0 =60 degrees is satisfied is depicted by a thin broken line. |E sum | obtained when ψ 0 =30 degrees is satisfied is depicted by a thick long and short dashed line, |E sum | obtained when ψ 0 =0 degrees is satisfied is depicted by a long and short dashed line with an intermediate thickness, and |E sum | obtained when ψ 0 =60 degrees is satisfied is depicted by a thin long and short dashed line. 
     As for |E G   sum | obtained when the REV method is performed by tracking movable body  60 , |E G   sum |≥9.995 is satisfied for any L when either ψ 0 =30 degrees, ψ 0 =0 degrees, or ψ 0 =60 degrees is satisfied. It can be thought that whatever value power transmission direction ψ 0  takes and whatever value L takes, |E G   sum |≥9.995 is satisfied. 
     When ψ 0 =30 degrees is satisfied, |E2 G   sum | obtained when the power transmission beam is fixed to the position of movable body  60  at the start of the REV method starts decreasing at the vicinity of log 10 (L/λ)=−0.25, that is, L=0.56*λ=33 mm and is decreased to |E2 G sum|=9 at log 10 (L/λ)=0.2, that is, L=1.59*λ=96 mm. When ψ 0 =0 degrees is satisfied, L at which the decrease starts is smaller than when ψ 0 =30 degrees is satisfied. When ψ 0 =0 degrees is satisfied, the decrease starts from the vicinity of log 10 (L/λ)=−0.4, that is, L=0.4*λ=24 mm and |E2 G   sum | is decreased to 9 at log 10 (L/λ)=0.08, that is, L=1.19*λ=72 mm. When ψ 0 =60 degrees is satisfied, L at which the decrease starts is larger than when ψ 0 =30 degrees. When ψ 0 =60 degrees is satisfied, the decrease starts from the vicinity of log 10 (L/λ)=0.15, that is, L=1.4*λ=84 mm and |E2 G   sum | is decreased to 9 at log 10 (L/λ)=0.65, that is, L=1.19*λ=72 mm. When |E2 G   sum | is decreased to about less than 6, |E2 G   sum | becomes higher or lower at random with respect to increase of L. The pattern of |E2 G   sum | becoming higher or lower with respect to increase of L can be thought to vary depending on phase error φp. 
     When L is small relative to λ (for example, L&lt;λ), change of the phase of power transmission radio wave  4  due to movement of the radiation target position is small, and the REV method can be executed accurately even when the power transmission beam is fixed to the position at the start of the REV method. This is satisfied for any power transmission direction ψ 0  to the position of movable body  60  at the start of the REV method. 
     The reasons why |E2 G   sum |≥9 can be maintained up to a larger L for larger ψ 0  are the following two reasons. 
     (A) When ψ 0  is larger, the beam width of the power transmission beam is larger. 
     (B) Since ξ 0 =90 degrees is satisfied, as wo is larger, the amount of change of the presence direction caused by movement of movable body  60  is smaller. 
     When ψ 0 =30 degrees is satisfied, the amplitude of composite electric field vector |E sum | obtained by performing the REV method with only the radiation direction of the power transmission beam tracking the movable body starts decreasing at the vicinity of log 10 (L/λ)=1.05, that is, L=11.2*λ=672 mm and is decreased to |E sum |=9 at log 10 (L/λ)=1.31, that is, L=23.2*λ=1392 mm. When ψ 0 =0 degrees is satisfied, L at which the decrease starts is smaller than when ψ 0 =30 degrees is satisfied. When ψ 0 =0 degrees is satisfied, the decrease starts at the vicinity of log 10 (L/λ)=1.0 that is, L=10.0*λ=600 mm and |E sum | is decreased to 9 at log 10 (L/λ)=1.25, that is, L=17.8*λ=1068 mm. When ψ 0 =60 degrees is satisfied, L at which the decrease starts is larger than when ψ 0 =30 degrees is satisfied. When ψ 0 =60 degrees is satisfied, the decrease starts at the vicinity of log 10 (L/λ)=1.33, that is, L=21.4*λ=1284 mm and |E sum | is decreased to 9 at log 10 (L/λ)=1.51, that is, L=32.4*λ=1944 mm. When |E sum | is decreased to less than approximately 6, |E2 G   sum | thereafter becomes higher or lower with respect to increase of L. 
     In the operation example described here, in any radiation direction ψ 0 , when L≤600 mm is satisfied, at the distance of G=1000 m, power transmission radio wave  2  can be calculated by the formula for a far field. The reasons why |E sum |≥9 can be maintained up to a larger L when ψ 0  is large are (A) and (B) explained above. 
     Referring to  FIG.  67    and  FIG.  68   , the amplitude of the composite electric field vector obtained by executing the REV method is studied, where distance L between element antennas  8  is changed satisfying G=1000 m, with several moving speeds v 0  of movable body  60 . For visibility of illustration, in  FIG.  67   , the graphs representing |E2 G   sum | when moving speed v 0  is either v 0 =−30 (m/sec), v 0 =−60 (m/sec), or v 0 =−15 (m/sec) is satisfied are depicted, and the graph representing |E sum | only when v 0 =−30 (m/sec) is satisfied is depicted. In  FIG.  68   , the graph representing |E2 G   sum |only when moving speed v 0  is v 0 =−30 (m/sec) is depicted, and the graphs representing |E sum | when v 0  is either v 0 =−30 (m/sec), v 0 =−60 (m/sec), or v 0 =−15 (m/sec) are depicted. In  FIG.  67    and  FIG.  68   , the graph representing |E2 6   sum | obtained when v 0 =−30 (m/sec) is satisfied is depicted by a thick broken line, the graph representing |E2 G   sum | obtained when v 0 =−60 (m/sec) is satisfied is depicted by a broken line with an intermediate thickness, and the graph representing |E2 G   sum | obtained when is satisfied v 0 =−15 (m/sec) is depicted by a thin broken line. The graph representing |E sum | obtained when v 0 =−30 (m/sec) is satisfied is depicted by a thick long and short dashed line, the graph representing |E sum | obtained when v 0 =−60 (m/sec) is satisfied is depicted by a long and short dashed line with an intermediate thickness, and the graph representing |E sum | obtained when v 0 =−15 (m/sec) is satisfied is depicted by a thin long and short dashed line. 
     As for |E G   sum | obtained when the REV method is performed by tracking movable body  60 , |E G   sum |≥9.995 is satisfied for any L when v 0  is either v 0 =−30 (m/sec), v 0 =−60 (in/sec), or v 0 =−15 (m/sec) is satisfied. It can be thought that whatever value moving speed v 0  takes and whatever value L takes, |E G   sum |≥9.995 is satisfied. 
     In  FIG.  67    and  FIG.  68   , the graph of |E2 G   sum | obtained when v 0 =−30 (m/sec) is satisfied with the power transmission beam fixed to the position of movable body  60  at the start of the REV method is the same as the graph of |E2 G   sum | obtained when ψ 0 =30 degrees is satisfied in  FIG.  66   . As illustrated in  FIG.  67   , |E2 G   sum | obtained when v 0 =−60 (m/sec) is satisfied starts decreasing at L smaller than that obtained when v 0 =−30 (m/sec) is satisfied. When v 0 =−60 (m/sec) is satisfied, the decrease starts at the vicinity of log 10 (L/λ)=−0.7, that is, L=0.2*λ=12 mm, and |E2 G   sum | is decreased to 9 at log 10 (L/λ)=−0.06, that is, L=0.88*λ=53 mm. When v 0 =−15 (m/sec) is satisfied, L at which the decrease starts is larger than when v 0 =−30 (m/sec) is satisfied. When v 0 =−15 (m/sec) is satisfied, the decrease starts at the vicinity of log 10 (L/λ)=0.15, that is, L=1.4*λ=84 mm, and |E2 G   sum | is decreased to 9 at log 10 (L/λ)=0.49, that is, L=3.09*λ=185 mm. When |E 2   G   sum | is decreased to about less than 6, |E2 G   sum | thereafter becomes higher or lower at random with respect to increase of L. 
     When L is small relative to λ (for example, L&lt;λ), change of the phase of power transmission radio wave  4  due to movement of the radiation target position is small, and the REV method can be executed accurately even when the power transmission beam is fixed to the position at the start of the REV method. This is satisfied for any moving speed v 0  of movable body  60 . 
     |E2 G   sum |≥9 can be maintained up to a larger L when moving speed v 0  is small for the following reason. 
     (C) When moving speed v 0  is small, the amount of change of the moving distance and the presence direction of movable body  60  during a period in which the REV method is executed is small. 
     In  FIG.  67    and  FIG.  68   , the graph of the amplitude of composite electric field vector |E sum | obtained when v 0 =−30 (m/sec) is satisfied and the REV method is performed with only the radiation direction of the power transmission beam tracking the movable body is the same as the graph of |E sum | obtained when ψ 0 =30 degrees is satisfied in  FIG.  66   . As illustrated in  FIG.  68   , the graphs of |E sum | obtained when v 0 =−60 (m/sec) is satisfied or when v 0 =−15 (m/sec) is satisfied are substantially the same as the graph when v 0 =−30 (in/sec) is satisfied. L at which |E sum | is decreased to 9 in the range of v 0 =−15 to −60 (m/sec) is in the range of log 10 (L/λ)=1.27 to 1.32, that is, L=18.8*λ to 20.7*λ=1130 to 1240 mm. 
     In the operation example described here, when L≤600 mm is satisfied and moving speed v 0  takes any value, at the distance of G=1000 m, power transmission radio wave  2  can be calculated by the formula for a far field. 
     Referring to  FIG.  69    and  FIG.  70   , the amplitude of the composite electric field vector obtained by executing the REV method is studied, where distance L between element antennas  8  is changed satisfying G=1000 m, with several moving directions ξ 0  of movable body  60 . For visibility of illustration, in  FIG.  69   , the graphs representing |E2 G   sum | obtained when moving direction ξ 0  is either ξ 0 =90 degrees, ξ 0 =120 degrees, or ξ 0 =60 degrees is satisfied are depicted, and the graph representing |E sum | only obtained when ξ 0 =90 degrees is satisfied is depicted. In  FIG.  70   , the graph representing |E2 G   sum | only when moving direction ξ 0  is ξ 0 =90 degrees is satisfied is depicted, and the graphs representing |E sum | obtained when either ξ 0 =90 degrees, ξ 0 =120 degrees, or ξ 0 =60 degrees is satisfied are depicted. In  FIG.  69    and  FIG.  70   , the graph representing |E2 G   sum | obtained when ξ 0 =90 degrees is satisfied is depicted by a thick broken line, the graph representing |E2 G   sum | obtained when ξ 0 =120 degrees is satisfied is depicted by a broken line with an intermediate thickness, and the graph representing |E2 G   sum | obtained when ξ 0 =60 degrees is satisfied is depicted by a thin broken line. The graph representing |E sum | obtained when ξ 0 =90 degrees is satisfied is depicted by a thick long and short dashed line, the graph representing |E sum | obtained when ξ 0 =120 degrees is satisfied is depicted by a long and short dashed line with an intermediate thickness, and the graph representing |E sum | obtained when ξ 0 =60 degrees is satisfied is depicted by a thin long and short dashed line. 
     As for |E G   sum | obtained when the REV method is performed by tracking movable body  60 , |E G sum|≥9.995 is satisfied for any L when either ξ 0 =90 degrees, ξ 0 =120 degrees, or ξ 0 =60 degrees is satisfied. It can be thought that whatever value moving direction ξ 0  takes and whatever value L takes, |E G sum|≥9.995 is satisfied. 
     In  FIG.  69    and  FIG.  70   , the graph of |E2 G   sum | obtained when ξ 0 =90 degrees is satisfied with the power transmission beam fixed to the position of movable body  60  at the start of the REV method is the same as the graph of |E2 G   sum | obtained when ψ 0 =30 degrees is satisfied in  FIG.  66   . As illustrated in  FIG.  69   , |E2 G   sum | obtained when ξ 0 =120 degrees is satisfied starts decreasing at L smaller than when ξ 0 =90 degrees is satisfied. When ξ 0 =120 degrees is satisfied, the decrease starts from the vicinity of log 10 (L/λ)=−0.35, that is, L=0.45*λ=27 mm and |E2 G   sum | is decreased to 9 at log 10 (L/λ)=0.13, that is, L=1.36*λ=81 mm. When ξ 0 =60 degrees is satisfied, L at which the decrease starts is larger than when ξ 0 =90 degrees is satisfied. When ξ 0 =60 degrees is satisfied, the decrease starts from the vicinity of log 10 (L/λ)=−0.1, that is, L=0.79*λ=47 mm and |E2 G   sum | is decreased to 9 at log 10 (L/λ)=0.41, that is, L=2.58*λ=155 mm. When |E2 G   sum | is decreased to about less than 6, |E2 G   sum | thereafter becomes higher or lower at random with respect to increase of L. 
     When L is small relative to λ (for example, L&lt;λ), change of the phase of power transmission radio wave  4  due to movement of the radiation target position is small, and the REV method can be executed accurately even when the power transmission beam is fixed to the position at the start of the REV method. This is satisfied for any moving direction ξ 0  of movable body  60 . 
     The reason why |E2 G   sum |≥9 can be maintained up to a larger L for smaller moving direction ξ 0  is the following reason. 
     (D) Since power transmission direction ψ 0 =30 degrees is satisfied, as ξ 0  is smaller, the amount of change of the presence direction caused by movement of movable body  60  is smaller. 
     In  FIG.  69    and  FIG.  70   , the graph of the amplitude of composite electric field vector |E sum | obtained when ξ 0 =90 degrees is satisfied and the REV method is performed with only the radiation direction of the power transmission beam tracking the movable body is the same as the graph of |E sum | obtained when ψ 0 =30 degrees is satisfied in  FIG.  66   . As illustrated in  FIG.  68   , the graphs of |E sum | obtained when ξ 0 =120 degrees is satisfied or when ξ 0 =60 degrees is satisfied are substantially the same as the graph when ξ 0 =90 degrees is satisfied. L at which |E sum | is decreased to 9 in the range of ξ 0 =60 to 120 degrees is in the range of log 10 (L/λ)=1.26 to 1.32, that is, L=18.1*λ to 20.7*λ=1090 to 1240 mm. 
     In the operation example described here, when L≤600 mm is satisfied and moving direction ξ 0  takes any value, at the distance of G=1000 m, power transmission radio wave  2  can be calculated by the formula for a far field. 
     In the wireless power transmission device in which the position of movable body  60  is recognized by direction and distance and the phases of power transmission radio waves are controlled to be matched at the position where movable body  60  is present, the REV method is executed by tracking the movable body during execution of the REV method, whereby the REV method can be executed accurately not depending on distance L between element antennas  8  that determines the size of the power transmission antenna, power transmission direction ψ, distance G to the movable body, and moving speed v 0  and moving direction ξ 0  of the movable body. Further, after execution of the REV method, wireless power transmission to the radiation target position determined by power transmission direction ψ and distance G can be performed efficiently, not depending on distance L between antennas  8 , power transmission direction ψ, distance G, moving speed v 0 , and moving direction ξ 0 . 
     In the wireless power transmission device in which the direction in which the movable body is present is set as the radiation direction of a power transmission radio wave, and the phases of power transmission radio waves are controlled to be matched at a distance of a far field at which element radio wave  2 E p  for each element antenna  8   p  travels parallel, REV method is executed by tracking the movable body during execution of the REV method in a state in which the movable body is present at a position at which wavelength λ of the power transmission radio wave, distance L between antennas  8 , and distance G to the movable body are a far field, whereby the REV method can be executed accurately not depending on transmission direction ψ, distance G to the movable body, moving speed v 0  and moving direction of the movable body. Further, after execution of the REV method, in a state in which the movable body is present at distance G that is a far field determined by wavelength λ and distance L between antennas  8 , wireless power transmission in power transmission direction ψ can be performed accurately, not depending on power transmission direction ψ, distance G, moving speed v 0 , and moving direction ξ 0 . 
     A modulated wave in which not only whether the power transmission radio wave is to be pulse-modulated but also timing information is included as a digital signal in a power transmission radio wave radiated by the power transmitter may be sent. The movable body may demodulate the power transmission radio wave and send the demodulated information by a pilot signal. When some process is performed in the movable body, the time required to perform the process in the movable body is set constant, so that the time to go back and forth between the wireless power transmission device and the movable body can be measured by subtracting the constant time. 
     The movable body distance may be measured based on the propagation time that is the time taken for a communication radio wave used for communication between the wireless power transmission device and the movable body to propagate both ways or one way between communication device  30  and movable body communication device  20 . 
     The distance measuring instrument that measures the distance from the position of the power transmission antenna to the position of the movable body may radiate distance-measurement waves such as laser light, non-laser light, radio waves, ultrasonic waves, or the like and receive distance-measurement reflected waves reflected by the movable body. The distance to the movable body may be measured based on the elapsed time from transmission of a distance-measurement wave to reception of a distance-measurement reflected wave. The distance is measured based on the measured elapsed time and the speed of the radiated distance-measurement wave. Instead of only being reflected by the movable body, the received signal may be amplified by the movable body and the amplified signal may be radiated in the direction of the wireless power transmission device. 
     The arrival time to the movable body may be measured in the movable body and the distance may be measured in the movable body, instead of measuring the time difference between both ways to the movable body. The movable body may radiate a radio wave and the like, and the wireless power transmission device may measure the time taken for the radio wave to reach the wireless power transmission device and measure the distance to the movable body. The movable body may radiate a radio wave and the like, and the movable body may measure the distance based on the time required for going to the wireless power transmission device and returning. The distance measured by the movable body may be sent by the movable body communication device or may be sent by modulating the pilot signal. 
     A radio wave or the like may be processed with spread spectrum by pseudo random number codes and the like, and the propagation time of the radio wave may be measured based on the code position subjected to reverse spread. 
     Not only the presence direction of the movable body but also the movable body position that is the position where the movable body is present may be measured, and the movable body position may be set as the radiation target position. 
     These are applicable to the other embodiments. 
     Eleventh Embodiment 
     In an eleventh embodiment, the tenth embodiment is modified such that the movable body position is measured using at least two pilot antennas for mono-pulse angle measurement. Referring to  FIG.  71    to  FIG.  73   , a configuration of the wireless power transmission system for a movable body according to the eleventh embodiment is described. In the eleventh embodiment, the movable body is not modified. Only the wireless power transmission device is modified. 
     In  FIG.  71   , points different from  FIG.  1    in the first embodiment are described. In  FIG.  72   , points different from  FIG.  2    in the first embodiment are described. In a wireless power transmission device  1 K, a control device  10 K is modified. Wireless power transmission device  1 K includes, in addition to pilot antenna  6  arranged at the center of power transmission antenna  50 , a pilot antenna  6 , and another arrival direction detecting device  7   2  (illustrated in  FIG.  72   ) at a distance from power transmission antenna  50 . Pilot antennas  6  and  6   2  are installed at different locations. Pilot antenna  6 , is similar to pilot antenna  6 . Pilot antenna  6   2  receives pilot signal  4  and generates a pilot reception signal. Arrival direction detecting device  7   2  has the same configuration as arrival direction detecting device  7 . Arrival direction detecting device  7   2  performs mono-pulse angle measurement on the pilot reception signal from pilot antenna  6   2  to determine arrival direction data  78   2  and outputs the same to control device  10 K. 
     In  FIG.  73   , points different from  FIG.  5    in the first embodiment are described. Control device  10 K does not include radiation direction determiner  33  and includes a radiation target position determiner  47 K. Radiation target position determiner  47 K determines a radiation target position determined by the radiation direction and the distance from power transmission antenna  50 . In control device  10 K, a data storage  25 K and a radio wave radiation controller  34 J are modified. Radio wave radiation controller  34 J is similar to that included in control device  10 J. 
     Data storage  25 K has radiation target position data  94  instead of radiation direction data  79 . Radiation target position data  94  is data representing the radiation target position set to be a target to radiate a radio wave by power transmission antenna  50 . Radiation target position data  94  is identical to that stored in data storage  25 J. Data storage  25 K also has arrival direction data  78   2  and pilot antenna position  98 . Arrival direction data  78   2  is the arrival direction of pilot signal  4  at the position of pilot antenna  6   2  that is detected by arrival direction detecting device  7   2 . Pilot antenna position  98  is data representing the positions of pilot antennas  6  and  6   2  with respect to power transmission antenna  50 . 
     Pilot antenna position  98  is pilot antenna installation location data that is data representing pilot antenna installation locations that are the locations where pilot antennas  6  and  6   2  are installed. Data storage  25 K is an installation location data storage that stores the pilot antenna installation location data. 
     Radiation target position determiner  47 K determines the position of movable body  60  (movable body position) by triangulation using arrival direction data  78  and  78   2  and pilot antenna position  98 . Radiation target position determiner  47 K determines the movable body position with respect to pilot antenna  6  as the radiation target position. Radiation target position determiner  47 K sets the determined radiation target position as radiation target position data  94  in data storage  25 K. Here, assuming that pilot transmitter  5  and power reception device  3  are near to each other in movable body  60 , the position of pilot transmitter  5  is set as the radiation target position. 
     The method by which radiation target position determiner  47 K determines the position of pilot transmitter  5  from arrival direction data  78  and  78   2  and pilot antenna position  98  is described. 
     The following variables are defined. 
     Point PA 1 : the position of pilot antenna  6  set in pilot antenna position  98 . 
     Point PA 2 : the position of pilot antenna  6   2  set in pilot antenna position  98 . 
     VA 1 : the directional vector represented by arrival direction data  78 . 
     VA 2 : the directional vector represented by arrival direction data  78 . 
     Point P 0 : the assumed position of pilot transmitter  5 . 
     VB 1 : the directional vector from point PA 1  toward point P 0 . 
     VB 2 : the directional vector from point PA 2  toward point P 0 . 
     EV(P 0 ): the evaluation function of an error in the directional vector determined from point P 0 . 
     Here, it is assumed that the magnitudes of all directional vectors VA 1 , VA 2 , VB 1 , and VB 2  are the same. That is, the following equation is satisfied. 
       | VA   1   |=|VA   2   |=|VB   1   |=|VB   2 |  (77)
 
     EV(P 0 ) is defined as follows. 
         EV ( P   0 )=| VA   1   −VB   1 | 2   +|VA   2   −VB   2 | 2   (78)
 
     Position P 0  of pilot transmitter  5  is determined such that EV(P 0 ) calculated by equation (78) is minimized. 
     When there are three or more Na pilot antennas  6 , EV(P 0 ) is changed as follows. 
         EV ( P   0 )=Σ| VA   k   −VB   k | 2   (79)
 
     In equation (79), Σ means summation for k=1, 2, . . . , Na. Such position P 0  that minimizes equation (79) is set as the position of pilot communication device  5 . 
     Radiation target position determiner  47 K is a movable body position determiner that determines the movable body position based on at least two arrival directions and the pilot antenna installation location data. Radiation target position determiner  47 K is a presence direction determiner that determines the presence direction based on the power transmission antenna position and the movable body position. Radiation target position determiner  47 K is a movable body distance measurer that measures the movable body distance based on the power transmission antenna position and the movable body position. 
     The operation is described.  FIG.  74    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the eleventh embodiment. In  FIG.  74   , points different from  FIG.  8    in the first embodiment are described. 
     In wireless power transmission device  1 K, SW and S 06 J are modified as in wireless power transmission device  1 J. At step S 01 J, wireless power transmission device  1 K radiates power transmission radio wave  2 , using the position at distance G and in the power transmission direction (ψ AZ , ψ EL ) where movable body  60  is present as the radiation target position. Power reception device  3  included in movable body  60  receives power transmission radio wave  2 . The process of executing the REV method at S 06 J is illustrated in  FIG.  61   , as in wireless power transmission device  1 J. 
     Steps S 11 K to S 13 K are modified. At S 11 K, pilot transmitter  5  included in movable body  60  transmits pilot signal  4 . Pilot antennas  6  and  6   2  included in wireless power transmission device  1  receive pilot signal  4  and generate a pilot reception signal. At step S 12 K, arrival direction detecting devices  7  and  7   2  each detect the arrival direction of pilot signal  4  by mono-pulse angle measurement for the pilot reception signal. At step S 13 K, radiation target position determiner  47 K determines the movable body position based on arrival direction data  78  and  78   2 . Further, the movable body position is converted into a relative position with respect to pilot antenna  2  and radiation target position  84  is determined. The radiation target position is a single point in which the power transmission direction (ψ AZ , ψ EL ) and distance G are determined. The power transmission direction is the direction from pilot antenna  6  toward the radiation target position. The pilot antenna  6  is installed at the center of the opening area of power transmission antenna  50 . The position of movable body  60  after the elapse of a predetermined time may be predicted based on the radiation target position and the moving speed of movable body  60 , and the predicted position may be set as the radiation target position. Power transmission antenna  50  radiates power transmission radio wave  2  at S 01 J to the radiation target position determined at S 13 K. 
     After S 13 K is performed, the process returns to S 11 K. The process at S 11 K to S 13 K is performed periodically in predetermined cycles. The length of one cycle is determined such that the difference between the radiation target position calculated last time and the current radiation target position is within an acceptable range even when movable body  60  moves at the possible maximum moving speed. 
     Wireless power transmission device  1 K operates similarly to wireless power transmission device  1 J and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. 
     Twelfth Embodiment 
     In a twelfth embodiment, the tenth embodiment is modified such that the movable body position is measured using three or more optical distance measuring instruments installed at different positions. In the twelfth embodiment, a movable body that does not include a pilot transmitter is used as in the seventh embodiment. The wireless power transmission device is modified. Referring to  FIG.  75    to  FIG.  77   , a configuration of a wireless power transmission system for a movable body, and the structure of a wireless power transmission device and a movable body according to the twelfth embodiment is described. 
     In  FIG.  75   , points different from  FIG.  1    in the first embodiment are described. In  FIG.  76   , points different from  FIG.  2    in the first embodiment are described. A movable body  60 F does not include pilot transmitter  5  and does not transmit pilot signal  4 . Movable body  60 F is not equipped with a position sensor and the like. A wireless power transmission device  1 L does not include pilot antenna  6 . 
     Wireless power transmission device  1 L includes three laser distance measuring instruments  48   1 ,  48   2 , and  48   3 . Laser distance measuring instruments  48   1 ,  48   2 , and  48   3  each are a distance measuring instrument that measures the distance from its position to movable body  60 F. Laser distance measuring instruments  48   1 ,  48   2 , and  48   3  radiate laser beams  43   1 ,  43   2 , and  43   3 , respectively. Laser beams  43   1 ,  43   2 , and  43   3  are reflected by movable body  60 F into reflected laser beams  44   1 ,  44   2 , and  44   3 , respectively. Laser distance measuring instruments  48   1 ,  48   2 , and  48   3  measure the time from emission of laser beams  43   1 ,  43   2 , and  43   3  to reception of reflected laser beams  44   1 ,  44   2 , and  44   3 , respectively. Laser distance measuring instruments  48   1 ,  48   2 , and  48   3  obtain distances GA 1 , GA 2 , and GA 3  from their positions to movable body  60 F based on the measured time. Laser distance measuring instruments  48   1 ,  48   2 , and  48   3  send the measured distances GA 1 , GA 2 , and GA 3  to control device  10 L. 
     Control device  10 L determines the position of movable body  60  from distances GA 1 , GA 2 , and GA 3  and data of the installation locations of laser distance measuring instruments  48   1 ,  48   2 , and  48   3 . Here, the point at distances GA 1 , GA 2 , and GA 3  from the installation locations of laser distance measuring instruments  48   1 ,  48   2 , and  48   3  is determined uniquely, and this point is the position of movable body  60 . In order to obtain the position of movable body  60  accurately, it is preferable that the installation locations of laser distance measuring instruments  48   1 ,  48   2 , and  48   3  are sufficiently distant from each other. 
     In  FIG.  77   , points different from  FIG.  5    in the first embodiment are described. Control device  10 L does not include radiation direction determiner  33  and includes a radiation target position determiner  47 L. Control device  10 L includes positioning sensor  40 . Radiation target position determiner  47 L determines the movable body position that is the position of movable body  60  using the distance to movable body  60 F measured by laser distance measuring instruments  48   1 ,  48   2 , and  48   3 . Laser distance measuring instruments  48   1 ,  48   2 , and  48   3  and radiation target position determiner  47 L constitute a movable body position measurer that measures the movable body position. Radiation target position determiner  47 L converts the movable body position into a radiation target position that is a relative position to the position of the power transmission antenna. The radiation target position is represented by the radiation direction and the distance to the radiation target position. 
     In control device  10 L, a data storage  25 L and radio wave radiation controller  34 J are modified. Radio wave radiation controller  34 J is similar to that included in control device  10 J. 
     Data storage  25 L has radiation target position data  94  instead of radiation direction data  79 . Data storage  25 L also has power transmission device position  84 , target position distance data  97   1 ,  97   2 , and  97   2 , and distance measuring instrument position  99 . Power transmission device position  84  is the position of power transmission antenna  50 J measured by positioning sensor  40 . Target position distance data  97   1 ,  97   2 , and  97   2  are distances GA 1 , GA 2 , and GA 3  measured by laser distance measuring instruments  48   1 ,  48   2 , and  48   3 . Distance measuring instrument position  99  is data representing the installation locations of laser distance measuring instruments  48   1 ,  48   2 , and  48   3 . 
     Distance measuring instrument position  99  is distance measuring instrument installation location data that is data representing the installation locations of laser distance measuring instruments  48   1 ,  48   2 , and  48   3 . Data storage  25 L is an installation location data storage that stores the distance measuring instrument installation location data. 
     Radiation target position determiner  47 L determines the position of movable body  60 F (movable body position) by trilateration using target position distance data  97   1 ,  97   2 , and  97   2  and distance measuring instrument position  99 . The position in three-dimensional space is determined uniquely when the distances from three points at known positions are determined. Since the positions of laser distance measuring instruments  48   1 ,  48   2 , and  48   3  are known and distances GA 1 , GA 2 , and GA 3  from laser distance measuring instruments  48   1 ,  48   2 , and  48   3  are determined, the position of movable body  60 F is determined. Radiation target position determiner  47 L subtracts power transmission device position  84  from the movable body position. The position obtained by subtraction is stored as radiation target position data  94  in data storage  25 K. 
     When there are four or more laser distance measuring instruments  48   k , the position of movable body  60 F is assumed, the distance from each laser distance measuring instrument  48   k  is calculated, and the position where, for example, the square sum of the difference from the measured distance actually is smallest is set as the position of movable body  60 F. 
     Radiation target position determiner  47 L is a movable body position determiner that determines the movable body position based on the distance measured by at least three distance measuring instruments and the distance measuring instrument installation location data. Radiation target position determiner  47 L is a presence direction determiner that determines the presence direction based on the power transmission antenna position and the movable body position. Radiation target position determiner  47 L is a movable body distance measurer that measures the movable body distance based on the power transmission antenna position and the movable body position. 
     The operation is described.  FIG.  78    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the thirteenth embodiment. In  FIG.  78   , points different from  FIG.  74    in the eleventh embodiment are described. 
     Steps S 91  to S 92  are performed instead of S 11 K to S 13 K. At S 91 , laser distance measuring instruments  48   1 ,  48   2 , and  48   3  each measure the distance from its position to movable body  60 F. At S 92 , radiation target position determiner  47 L determines the movable body position and the radiation target position by trilateration using target position distance data  97   1 ,  97   2 , and  97   2  and distance measuring instrument position  99 . 
     Wireless power transmission device  1 L operates similarly to wireless power transmission device  1 J and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. 
     The distance measuring instruments may be those that radiate non-laser light, radio waves, ultrasonic waves, or the like. 
     Thirteenth Embodiment 
     In a thirteenth embodiment, the eleventh embodiment is modified such that the movable body includes an attitude sensor and the position of power reception device  3  is obtained from the position of the pilot transmitter based on attitude data of the movable body. The thirteenth embodiment is an embodiment suitable for a case where the movable body is large and the pilot transmitter and the power reception device are not close to each other. Referring to  FIG.  79    to  FIG.  81   , a configuration of a wireless power transmission system for a movable body, and the structure of a wireless power transmission device and a movable body according to the thirteenth embodiment is described. 
     In  FIG.  79   , points different from  FIG.  71    in the eleventh embodiment are described.  FIG.  80   , points different from  FIG.  72    in the eleventh embodiment are described. In  FIG.  81   , points different from  FIG.  73    in the eleventh embodiment are described. A wireless power transmission device  1 M and a movable body  60 M are modified. Movable body  60 M includes attitude sensor  66  and an attitude data sender  69 . Attitude sensor  66  measures the attitude of movable body  60 M. Attitude data sender  69  performs the process of sending attitude data  82  measured by attitude sensor  66  to control device  10 M periodically. When the movable body position measured by positioning sensor  65  is not close to the position of power reception device  3 , control device  10 M corrects the movable body position using the attitude measured by attitude sensor  66  and structure data representing the structure of movable body  60 M and determines the position of power reception device  3 . 
     In movable body  60 M, a data storage device  21 M is modified. Data storage device  21 M also stores attitude data  82 . Attitude data  82  is data representing the attitude of movable body  60 E measured by attitude sensor  66 . Attitude data  82  is, for example, data representing that the nose direction is horizontal and the north-east direction. 
     In wireless power transmission device  1 M, control device  10 M is modified. In control device  10 M, a radiation target position determiner  47 M and a data storage  25 M are modified. Data storage  25 M also stores power reception device position  85 , movable body structure data  83 , and attitude data  82 . Power reception device position  85  is the position of power reception device  3 . Movable body structure data  83  is data representing the position of power reception device  3  with respect to pilot transmitter  5  in movable body  60 M. Movable body structure data  83  is, for example, data representing that the position of power reception device  3  is 10 m to the front of pilot transmitter  5  in the nose direction. Attitude data  82  is data sent from movable body  60 M. Data storage  25 M is a movable body data storage that stores the movable body structure data. 
     Radiation target position determiner  47 M determines the position of pilot transmitter  5  from arrival direction data  78  and  78   2  and pilot antenna position  98 , similarly to radiation target position determiner  47 K. Radiation target position determiner  47 M further refers to movable body structure data  83  and attitude data  82  to determine power reception device position  85  with respect to the position of pilot transmitter  5 . Radiation target position determiner  47 M sets power reception device position  85  as the movable body position. Radiation target position determiner  47 M sets the movable body position with respect to pilot antenna  6  as the radiation target position. Radiation target position determiner  47 M sets the radiation target position as radiation target position data  94  in data storage  25 M. 
     Radiation target position determiner  47 M is a movable body position determiner that determines the movable body position based on at least two arrival directions and the pilot antenna installation location data. Radiation target position determiner  47 M is a presence direction determiner that determines the presence direction based on the power transmission antenna position and the movable body position. Radiation target position determiner  47 M is a movable body distance measurer that measures the movable body distance based on the power transmission antenna position and the movable body position. Radiation target position determiner  47 M is a power reception device position determiner that determines power reception device position  85  using movable body structure data  83  and attitude data  82 . 
     The operation is described.  FIG.  81    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the thirteenth embodiment. In  FIG.  81   , points different from  FIG.  74    in the first embodiment are described. 
     In wireless power transmission device  1 M, step S 13 M is modified and step S 17  is added after S 13 M. At S 13 M, radiation target position determiner  47 M determines the position of pilot transmitter  5  as the movable body position from arrival directions  78  and  78   2 . At S 17 , radiation target position determiner  47 M determines power reception device position  85  based on the position of pilot transmitter  5 , using attitude data  82  and movable body structure data  83 . Power reception device position  85  is set as the movable body position and the radiation target position. The movable body position with respect to pilot antenna  6  is the radiation target position. Radiation target position determiner  47 M sets the determined radiation target position as radiation target position data  94  in data storage  25 M. 
     Using attitude data  82  and movable body structure data  83 , power reception device position  85  can be determined as the radiation target position. Wireless power transmission device  1 M can perform wireless power transmission efficiently using power reception device position  85  as a radiation target when movable body  60  is large and pilot transmitter  5  and power reception device  3  are not close to each other. 
     Wireless power transmission device  1 M operates similarly to wireless power transmission device  1 J and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. 
     Fourteenth Embodiment 
     In a fourteenth embodiment, the sixth embodiment is modified such that the wireless power transmission device radiates a power transmission radio wave (power transmission beam) so that the maximum electric power can be received at the movable body position. Referring to  FIG.  83    to  FIG.  85   , a configuration of a wireless power transmission system for a movable body, and the structure of a wireless power transmission device and a movable body according to the fourteenth embodiment is described. In the sixth embodiment, the movable body is equipped with a positioning sensor to measure its position. The wireless power transmission device determines the presence direction that is the direction in which the movable body is present, based on the movable body position sent from the movable body. In this fourteenth embodiment, the radiation target position is determined based on the movable body position sent from the movable body, and the phase of each element radio wave  2 E p  is controlled such that the phase of each element radio wave  2 E p  is matched at the radiation target position. 
     In  FIG.  83   , points different from  FIG.  38    in the sixth embodiment are described. In  FIG.  84   , points different from  FIG.  39    in the sixth embodiment are described. In  FIG.  85   , points different from  FIG.  40    in the sixth embodiment are described. A wireless power transmission device  1 N is modified. Movable body  60 E is not modified. Movable body  60 E includes positioning sensor  65  and attitude sensor  66 . 
     In wireless power transmission device  1 N, a control device  10 N is modified. In control device  10 N, a data storage  25 N and radiation controller  34 J are modified. Radio wave radiation controller  34 J is similar to that included in control device  10 J. Control device  10 N does not include radiation direction determiner  33 E and includes a radiation target position determiner  47 N. Data storage  25 N does not have radiation direction data  79  and has radiation target position data  94 . Radiation target position determiner  47 N sets radiation target position data  94  obtained by converting power reception device position  85  into a relative position to power transmission device position  84 , based on movable body position  81  and power transmission device position  84 . Radio wave radiation controller  34 J generates radiation command values  80  such that power transmission antennas  50  radiate power transmission radio waves  2  with the phases matched at the radiation target position stored in radiation target position data  95 . 
     The operation is described.  FIG.  86    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the fourteenth embodiment. In  FIG.  86   , points different from  FIG.  41    in the sixth embodiment are described. 
     In wireless power transmission device  1 N, step S 01 J and step S 24 N are modified. S 01 J is similar to that in the tenth embodiment. At step S 01 J, wireless power transmission device  1 N radiates power transmission radio wave  2 , using the position at distance G and in the power transmission direction (ψ AZ , ψ EL ) where movable body  60 E is present as the radiation target position. Power reception device  3  included in movable body  60 E receives power transmission radio wave  2 . S 01 J includes a process similar to the process at S 26  in  FIG.  41   . 
     At step S 24 N, radiation target position determiner  47 N determines radiation target position data  94  by converting power reception device position  85  into a relative position to power transmission device position  84 , based on movable body position  81  and power transmission device position  84 . 
     Wireless power transmission device  1 N operates similarly to wireless power transmission device  1 J and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. 
     Fifteenth Embodiment 
     In a fifteenth embodiment, the seventh embodiment is modified such that the wireless power transmission device radiates a power transmission radio wave (power transmission beam) so that the maximum electric power can be received at the movable body position. Referring to  FIG.  87    to  FIG.  89   , a configuration of a wireless power transmission system for a movable body, and the structure of a wireless power transmission device and a movable body according to the fifteenth embodiment is described. In the seventh embodiment, the wireless power transmission device includes a movable body position measuring device that measures the position of the movable body. 
     In  FIG.  87   , points different from  FIG.  42    in the seventh embodiment are described. In  FIG.  88   , points different from  FIG.  43    in the seventh embodiment are described. In  FIG.  89   , points different from  FIG.  44    in the seventh embodiment are described. A wireless power transmission device  1 N is modified. Movable body  60 F is not modified. The modification in the fifteenth embodiment from the seventh embodiment is similar to the modification in the fourteenth embodiment from the sixth embodiment. 
     In a wireless power transmission device  1 P, a control device  10 P is modified. In control device  10 P, a data storage  25 P and radiation controller  34 J are modified. Radio wave radiation controller  34 J is similar to that included in control device  10 J. Control device  10 P does not include radiation direction determiner  33  and includes radiation target position determiner  47 N. Data storage  25 N does not have radiation direction data  79  and has radiation target position data  94 . 
       FIG.  89    differs from  FIG.  85    in the fourteenth embodiment in that wireless power transmission device  1 P includes laser positioning device  42  and control device  10 P is modified. Movable body  60 E is changed to movable body  60 F that does not include positioning sensor  65  and attitude sensor  66 . Control device  10 P differs from control device  10 N in that it does not include movable body position determiner  41  and data storage  25 P has power reception device position  85 F instead of power reception device position  85 . Power reception device position  85 F is data measured by laser positioning device  42 . 
     The operation is described.  FIG.  90    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the fifteenth embodiment. In wireless power transmission device  1 P, compared with  FIG.  45    in the seventh embodiment, step S 01 J and step S 24 N are modified similarly to wireless power transmission device  1 N.  FIG.  90    differs from  FIG.  86    in the fourteenth embodiment in S 21 F and S 22 F. S 21 F and S 22 F are the process in which the laser positioning device measures the power reception device position and inputs the measured power reception device position to the control device. At S 24 N, radiation target position determiner  47 N determines radiation target position data  94  by converting power reception device position  85  into a relative position to power transmission device position  84 , based on movable body position  81  and power transmission device position  84 . 
     Wireless power transmission device  1 P operates similarly to wireless power transmission device  1 J and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. 
     Sixteenth Embodiment 
     In a sixteenth embodiment, the tenth embodiment is modified such that the distance to the movable body is measured by a communication radio wave used for communication. Referring to  FIG.  91    to  FIG.  93   , a configuration of a wireless power transmission system for a movable body, and the structure of a wireless power transmission device and a movable body according to the sixteenth embodiment is described. 
     In  FIG.  91   , points different from  FIG.  50    in the tenth embodiment are described. In  FIG.  92   , points different from  FIG.  51    in the tenth embodiment are described. In  FIG.  93   , points different from  FIG.  52    in the tenth embodiment are described. A wireless power transmission device  1 Q and a movable body  60 Q are modified. 
     Communication for measuring the distance is performed between wireless power transmission device  1 Q and movable body  60 Q, and the distance between power transmission antenna  50  and movable body  60 Q is measured based on the time required for communication. Wireless power transmission device  1 Q includes power transmission antenna  50  similar to that included in wireless power transmission device  1 . Power transmission radio wave  2  and pilot signal  4  are not pulse-modulated. 
     In wireless power transmission device  1 Q, arrival direction detecting device  7  and a control device  10 Q are modified. Unlike arrival direction detecting device  7 J, arrival direction detecting device  7  has only the function of detecting the arrival direction of pilot signal  4 . In control device  10 Q, a data storage  25 Q and a distance meter  46 Q are modified. Data storage  25 Q does not have pulse transmission time  95  and pulse reception time  96  and has distance measurement transmission time  95 Q and distance measurement reception time  96 Q instead of them. 
     Movable body  60 Q includes pilot transmitter  5  and detector  18  similar to those of movable body  60 . In movable body  60 Q, an on-board control device  19 Q is modified. On-board control device  19 Q does not include pulse modulation manager  68  and includes a distance measurement communicator  68 Q, instead. When receiving a distance measurement signal  53  sent by wireless power transmission device  1 Q, distance measurement communicator  68 Q sends a distance measurement response signal  54  to wireless power transmission device  1 Q when a predetermined time T 1 Q has elapsed since the time when distance measurement signal  53  is received. 
     Distance meter  46 Q sends distance measurement signal  53  to movable body  60 Q and receives distance measurement response signal  54  sent by movable body  60 Q. Distance meter  46 Q stores the time when distance measurement signal  53  is sent as distance measurement transmission time  95 Q into data storage  25 Q. Distance meter  46 Q stores the time when distance measurement response signal  54  is received as distance measurement reception time  96 Q into data storage  25 Q. Distance meter  46 Q measures time T 2 Q from transmission of distance measurement signal  53  to reception of distance measurement response signal  54 . Distance meter  46 Q calculates time T 3 Q=T 2 Q−T 1 Q by subtracting T 1 Q from T 2 Q. Distance meter  46 Q measures the distance between power transmission antenna  50  and movable body  60 Q based on T 3 Q. Distance meter  46 Q stores the measured distance as target position distance data  97  into data storage  25 Q. 
     When the distance between communication device  30  and power transmission antenna  50  cannot be ignored, target position distance data  97  is determined by correcting the distance calculated from T 2 Q based on data representing the positional relation between communication device  30  and power transmission antenna  50 . 
     When the distance between movable body communication device  20  and power reception device  3  cannot be ignored, attitude data  82  is sent from movable body  60 , and the power reception device position is obtained based on attitude data  82  and movable body structure data  83 . Arrival direction data  78  and target position distance data  97  may be corrected based on the power reception device position. 
     The operation is described.  FIG.  94    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the sixteenth embodiment. In  FIG.  94   , points different from  FIG.  52    in the tenth embodiment are described. 
     Steps S 81 Q to S 84 Q are modified. At S 81 Q, distance meter  46 Q sends distance measurement signal  53  and records distance measurement transmission time  95 Q. At S 82 Q, movable body  60 Q receives distance measurement signal  53  and sends distance measurement response signal  54  at a time when T 1 Q elapses from the reception. At S 83 Q, pilot antenna  6  receives pilot signal  4 , and arrival direction detecting device  7  detects the arrival direction of pilot signal  4 J by mono-pulse angle measurement. At S 84 Q, when distance meter  46 Q receives distance measurement response signal  54 , the time at that moment is set in distance measurement reception time  96 Q. Distance meter  46 Q determines target position distance G based on time difference T 3 Q between distance measurement reception time  96 Q and distance measurement transmission time  95 Q and sets target position distance data  97 . 
     Wireless power transmission device  1 Q operates similarly to wireless power transmission device  1 J and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. 
     Seventeenth Embodiment 
     In a seventeenth embodiment, the fourteenth embodiment is modified such that the position of the movable body is predicted and the radiation target position is determined such that the radiation target position includes the predicted position of the movable body. Another embodiment may be modified. Referring to  FIG.  95    to  FIG.  97   , a configuration of a wireless power transmission system for a movable body, and the structure of a wireless power transmission device and a movable body according to the seventeenth embodiment is described. In the fourteenth embodiment, the movable body includes a positioning sensor and an attitude sensor and the radiation target position is determined such that the radiation target position includes the power reception device position. 
     In  FIG.  95   , points different from  FIG.  86    in the fourteenth embodiment are described. In  FIG.  96   , points different from  FIG.  84    in the fourteenth embodiment are described. In  FIG.  97   , points different from  FIG.  85    in the fourteenth embodiment are described. A wireless power transmission device  1 R is modified. Movable body  60 E is not modified. 
     In wireless power transmission device  1 R, only a control device  10 R is modified. Control device  10 R includes a movable body position predictor  49  to predict the position of movable body  60 E. In control device  10 R, a data storage  25 R, a movable body position determiner  41 R, and a radiation target position determiner  47 R are modified. 
     In data storage  25 R, movable body position  81 R and attitude data  82 R are modified and data storage  25 R includes predicted movable body position  55 . Data storage  25 R has predicted power reception device position  85 R instead of power reception device position  85 . Movable body position  81 R is data representing the movable body position measured in an immediate period having a predetermined length TR (for example, a few seconds). Attitude data  82 R is attitude data measured in an immediate period having length TR. Predicted movable body position  55  is data representing the movable body position and the attitude data predicted by movable body position predictor  49 . Predicted power reception device position  85 R is data representing the power reception device position determined by movable body position determiner  41 R based on predicted movable body position  55 . 
     Movable body position predictor  49  predicts the movable body position and the attitude data after a prediction time TS. Prediction time TS is determined as appropriate in accordance with the processing time in wireless power transmission device  1 J and the distance to movable body  60 . Predicting the movable body position enables efficient power transmission to movable body  60  even the process of detecting the position of movable body  60  or the computation for obtaining a phase correction value takes time. Movable body position predictor  49  predicts the movable body position after prediction time TS by approximating the movable body position in a period having length TR stored as movable body position  81 R by a linear or quadratic equation with respect to time. The predicted movable body position is stored as predicted movable body position  55 . Movable body position predictor  49  predicts the attitude data after prediction time TS by approximating the attitude data in a period having length TR stored as attitude data  82 R by a linear or quadratic equation with respect to time. When the attitude data is represented by, for example, yaw angle, pitch angle, and roll angle, the attitude data is predicted for each of yaw angle, pitch angle, and roll angle. The predicted attitude data is stored as predicted movable body position  55 . In order to reduce noise effects, the moving averages of the movable body position and the attitude data may be obtained, and linear or quadratic approximate equations of the moving average value with respect to time may be obtained. 
     Movable body position determiner  41 R predicts a power reception device position based on predicted movable body position  55  (including the predicted attitude data) and movable body structure data  83 . The predicted power reception device position is stored as predicted power reception device position  85 R in data storage  25 R. 
     Radiation target position determiner  47 R determines radiation target position data  94  such that radiation target position data  94  includes predicted power reception device position  85 R. When the movable body is small, the power reception device position is not necessarily predicted and radiation target position data  94  may be determined such that radiation target position data  94  includes the predicted movable body position. 
     Data storage  25 R is a movable body position history storage that stores movable body position  81 R that is data representing the movable body position measured in an immediate period having length TR. Data storage  25 R is also an attitude data history storage that stores attitude data  82 R that is data representing the attitude data measured in an immediate period having length TR. An immediate period having length TR is a predetermined range of time. The range of time may be determined such that, for example, the time when the latest arrival direction is measured is not included. 
     Movable body position predictor  49  is a movable body position predictor that predicts a movable body position. Movable body position predictor  49  predicts a movable body position based on movable body position  81 R stored in data storage  25 R. Predicted movable body position  55  is a movable body position predicted by movable body position predictor  49 . 
     Movable body position predictor  49  is also a power reception device position predictor that predicts a power reception device position. Movable body position predictor  49  predicts a power reception device position based on movable body position  81 R and attitude data  82 R stored in data storage  25 R. Predicted power reception device position  85 R is a power reception device position predicted by movable body position predictor  49 . 
     The operation is described.  FIG.  98    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the seventeenth embodiment. In  FIG.  98   , points different from  FIG.  86    in the fourteenth embodiment are described. S 23  is changed to S 23 R. S 27  is added before S 23 R. 
     At S 27 R, a movable body position and attitude data are predicted based on movable body position  81 R and attitude data  82 R in the immediate past (period having length TR). The predicted movable body position and attitude data are stored as predicted movable body position  55  in data storage  25 R. 
     At S 23 R, movable body position determiner  41 R determines a power reception device position based on predicted movable body position  55  (including the predicted attitude data) and movable body structure data  83 . The determined power reception device position is stored as predicted power reception device position  85 R in data storage  25 R. 
     At S 24 R, a radiation target position is determined such that the radiation target position includes the predicted power reception device position. Power transmission radio waves  2  are radiated at S 01 J and S 06 J such that the phase of power transmission radio waves  2  are matched at the radiation target position. 
     Wireless power transmission device  1 R operates similarly to wireless power transmission device  1 J and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. Since the phase of element radio wave  2 E p  radiated by each element antenna  8   p  is controlled also in consideration of the distance to movable body  60 , the power transmission efficiency can be made higher than when the phase is controlled such that only the radiation direction tracks the movable body when power transmission antenna  50  is large or the distance to movable body  60  is small. 
     The position and the attitude of the movable body are predicted, and the position of the power reception device is predicted based on the predicted position and attitude of the movable body. Since the radiation target position is determined such that the radiation target position includes the predicted position of the power reception device, power can be transmitted to the power reception device more efficiently even when the process of detecting the positions of the movable body and the power reception device or the computation for obtaining a phase correction value takes time. The position of the movable body may be predicted, and the radiation target position may be determined such that the radiation target position includes the predicted position of the movable body. 
     The presence direction may be predicted based on the predicted power reception device position and the power transmission antenna position. The position of the power reception device may be predicted, and the direction from the power transmission antenna position toward the predicted power reception device may be predicted as the presence direction. The radiation direction changer may direct the radiation direction in the predicted presence direction that is the presence direction predicted. 
     The method of predicting a movable body position may be the method in the tenth embodiment and other embodiments or may be a method not mentioned in the present description. 
     These are applicable to the other embodiments. 
     Eighteenth Embodiment 
     In an eighteenth embodiment, the sixth embodiment is modified such that the position of the movable body is predicted and the radiation direction is determined such that the predicted position of the movable body is directed at. Another embodiment may be modified. Referring to  FIG.  99    to  FIG.  101   , a configuration of a wireless power transmission system for a movable body, and the structure of a wireless power transmission device and a movable body according to the eighteenth embodiment is described. In the sixth embodiment, the movable body position measuring device is installed near the wireless power transmission device, and the wireless power transmission device directs the radiation direction of a power transmission beam in the power reception device position measured by the movable body position measuring device. 
     In  FIG.  99   , points different from  FIG.  42    in the sixth embodiment are described. In  FIG.  100   , points different from  FIG.  43    in the sixth embodiment are described. In  FIG.  101   , points different from  FIG.  44    in the sixth embodiment are described. A wireless power transmission device  1 S is modified. Movable body  60 F is not modified. 
     In wireless power transmission device  1 S, a control device  10 S and a laser positioning device  42 S are modified. Laser positioning device  42 S measures not only power reception device position  85 F but also movable body position  81 F. Laser positioning device  42 S is a movable body position measuring device that measures the movable body position and the power reception device position. Movable body position  81 F is the position of the center of gravity of a spatial range in which movable body  60 F is present that is measured by laser positioning device  42 S. Instead of the center of gravity, the position of the center in the range of each of the horizontal direction, the vertical direction, and the depth direction of a spatial range in which movable body  60 F is present may be set as the movable body position. Movable body position  81 F may be determined to be any position included in a spatial range in which movable body  60 F is present. Power reception device position  85 F and movable body position  81 F measured by laser positioning device  42 S are inputted to control device  10 S. Power reception device position  85 F is converted in a relative position to movable body position  81 F. 
     Control device  10 S includes a movable body position predictor  49 S that predicts the positions of movable body  60 F and power reception device  3 . In control device  10 S, a data storage  25 S and a radiation direction determiner  33 S are modified. In data storage  25 S, power reception device position  85 S is modified and data storage  25 S includes movable body position  81 S and predicted power reception device position  85 R. Power reception device position  85 S is data that stores power reception device position  85 F measured by laser positioning device  42 S in an immediate period having length TR. Movable body position  81 S is data that stores movable body position  81 F measured by laser positioning device  42 S in an immediate period having length TR. Predicted power reception device position  85 R is data representing the position of power reception device  3  predicted by movable body position predictor  49 S. Radiation direction determiner  33 S determines the presence direction of predicted power reception device position  85 R viewed from power transmission device position  84 , that is, the presence direction that is the direction from power transmission device position  84  toward predicted power reception device position  85 R. Further, radiation direction determiner  33 S determines the radiation direction from the presence direction. 
     Movable body position predictor  49 S predicts the movable body position and the power reception device position after prediction time TS. Movable body position predictor  49 S predicts the movable body position after prediction time TS by approximating the movable body position in a period having length TR stored as movable body position  81 S by a linear or quadratic equation with respect to time. Movable body position predictor  49 S predicts the power reception device position after prediction time TS by approximating the power reception device position in a period having length TR stored as power reception device position  85 S by a linear or quadratic equation with respect to time. The position obtained by adding the predicted power reception device position to the predicted movable body position is stored as predicted power reception device position  85 R in data storage  25 S. Laser positioning device  42 S converts power reception device position  85 F into a relative position with respect to movable body position  81 F. Therefore, the position obtained by adding the predicted power reception device position to the predicted movable body position is the predicted position of power reception device  3  after prediction time TS. 
     In order to reduce noise effects, the moving averages of the movable body position and the power reception device position may be obtained, and linear or quadratic approximate equations of the moving average values with respect to time may be obtained. The power reception device position may be measured by the laser positioning device as a position in three-dimensional space, and only the power reception device position may be processed to predict the power reception device position. It can be thought that the power reception device position can be predicted more precisely by predicting both of the movable body position and the power reception device position, for example, when the movable body changes its attitude while moving. The movable body position may be predicted instead of the power reception device position. 
     Data storage  25 S is a movable body position history storage that stores movable body position  81 S that is data representing the movable body position measured in an immediate period having length TR. Data storage  25 S is a power reception device position history storage that stores power reception device position  85 S that is data representing the power reception device position measured in an immediate period having length TR. 
     Movable body position predictor  49 S is a movable body position predictor that predicts a movable body position. Movable body position predictor  49 S is also a power reception device position predictor that predicts a power reception device position. Movable body position predictor  49 S is a power reception device predictor that predicts a power reception device position based on movable body position  81 S and power reception device position  85 S. Predicted power reception device position  85 R is a power reception device position predicted by movable body position predictor  49 S. 
     Radiation direction determiner  33 S is a presence direction determiner that determines the presence direction based on predicted power reception device position  85 R and the power transmission antenna position. 
     The operation is described.  FIG.  102    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the eighteenth embodiment. In  FIG.  102   , points different from  FIG.  45    in the sixth embodiment are described. 
     Steps S 21 S, S 22 S, and S 24 S are modified, and step S 27 S is added before S 24 S. S 26  is removed. At S 21 S, laser positioning device  42 S measures power reception device position  85 F and movable body position  81 F. At S 22 S, power reception device position  85 F and movable body position  81 F are inputted to control device  10 S. The control device stores the input power reception device position  85 F and movable body position  81 F for a period equal to or longer than length TR. 
     At S 27 S, movable body position predictor  49 S predicts a movable body position and a power reception device position, based on movable body position  81 S and power reception device position  85 S in the immediate past (period having length TR). The predicted power reception device position is stored as predicted power reception device position  85 R in data storage  25 S. 
     At S 24 S, the presence direction of predicted power reception device position  85 R viewed from power transmission device position  84  is determined. At S 25 , radiation direction determiner  33 S determines the power transmission direction (ψ AZ , ψ EL ) from the presence direction. At S 01 J and S 06 J, power transmission radio wave  2  is radiated in the radiation direction set to the direction toward the predicted position of power reception device  3 . 
     Wireless power transmission device  1 S operates similarly to wireless power transmission device  1 J and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. 
     The position of the power reception device is predicted, the direction toward the predicted position of the power reception device is set as the presence direction of the movable body, and the radiation direction of power transmission radio wave  2  is determined from the presence direction. Since the position of the power reception device is predicted, power can be transmitted to the power reception device more efficiently. The position of the movable body may be predicted, and the direction toward the predicted position of the movable body may be set as the presence direction of the movable body. 
     The power reception device position may be predicted based on the power reception device position in a predetermined range of time, and the presence direction may be determined based on the predicted power reception device position and the power transmission antenna position. 
     The radiation target position may be determined such that the radiation target position includes the movable body position or the power reception device position, and the power transmission radio waves may be radiated such that the phases of the power transmission radio waves are matched at the radiation target position. 
     These are applicable to the other embodiments. 
     Nineteenth Embodiment 
     In a nineteenth embodiment, the first embodiment is modified such that the arrival direction of a pilot signal is predicted and the radiation direction of the power transmission radio wave is determined based on the predicted arrival direction. Another embodiment may be modified. Referring to  FIG.  103    to  FIG.  105   , a configuration of a wireless power transmission system for a movable body, and the structure of a wireless power transmission device and a movable body according to the nineteenth embodiment is described. 
     In  FIG.  103   , points different from  FIG.  1    in the first embodiment are described. In  FIG.  104   , points different from  FIG.  2    in the first embodiment are described. In FIG.  105 , points different from  FIG.  5    in the first embodiment are described. A wireless power transmission device  1 T is modified. Movable body  60  is not modified. 
     In wireless power transmission device  1 T, only a control device  10 T is modified. Control device  10 T includes an arrival direction predictor  49 T that predicts the arrival direction of pilot signal  4  after prediction time TS. In control device  10 T, a data storage  25 T and a radiation direction determiner  33 T are modified. In data storage  25 T, arrival direction data  78 T is modified and data storage  25 T includes predicted arrival direction data  56 . Arrival direction data  78 T is data that stores arrival direction data  78  detected by arrival direction detecting device  7  in an immediate period having length TR. Predicted arrival direction data  56  is data representing the arrival direction predicted by arrival direction predictor  49 T. The arrival direction is also the presence direction that is the direction in which movable body  60  is present. Radiation direction determiner  33 T refers to predicted arrival direction data  56  to determine the radiation direction. 
     Arrival direction predictor  49 T predicts the arrival direction of pilot signal  4  after prediction time TS based on arrival direction data  78 T. Arrival direction predictor  49 T predicts the arrival direction after prediction time TS by approximating the arrival direction in a period having length TR stored as arrival direction data  78 T by a linear or quadratic equation with respect to time. The predicted arrival direction is stored as predicted arrival direction data  56  in data storage  25 T. In order to reduce noise effects, the moving average of the arrival direction may be obtained, and a linear or quadratic approximate equation of the moving average value with respect to time may be obtained. 
     Arrival direction predictor  49 T is a presence direction predictor that predicts the presence direction based on the pilot reception signal. Predicted arrival direction data  56  is data representing the predicted presence direction that is the presence direction predicted by arrival direction predictor  49 T. Radiation direction determiner  33 T directs the radiation direction in the predicted presence direction. The presence direction predictor may predict the presence direction based on any other than the pilot reception signal. 
     Arrival direction data  78 T is the presence direction determined in a predetermined range of time. Data storage  25 T is a presence direction history storage that stores the presence direction determined in a predetermined range of time. Data storage  25 T is also an arrival direction history storage that stores the arrival direction determined in a predetermined range of time. 
     The operation is described.  FIG.  106    is a flowchart illustrating a power transmission procedure to a movable body by the wireless power transmission device according to the nineteenth embodiment. In  FIG.  106   , points different from  FIG.  8    in the first embodiment are described. 
     Step S 131  is modified, and step S 18  is added before S 13 T. At S 18 , arrival direction predictor  49 T predicts the arrival direction after prediction time TS based on arrival direction data  78 T in the immediate past (period having length TR). At S 13 T, radiation direction determiner  33 T determines the radiation direction based on the predicted arrival direction. 
     Wireless power transmission device  1 T operates similarly to wireless power transmission device  1  and a similar effect can be obtained. Since the power transmission beam tracks movable body  60  during execution of the REV method, the accuracy of the REV method can be increased. 
     Since the arrival direction of the pilot signal is predicted and the presence direction is determined based on the predicted arrival direction, power can be transmitted to the power reception device more efficiently. The presence direction may be predicted even when the presence direction of the movable body is determined from data different from the arrival direction of the pilot signal. Predicting the presence direction enables more efficient power transmission to the power reception device. 
     The embodiments may be combined as desired, or the embodiments may be modified or constituent elements thereof may be partially omitted, or the embodiments with constituent elements partially omitted or modified may be combined as desired. 
     REFERENCE SIGNS LIST 
     
         
         
           
               1 ,  1 A,  1 B,  1 C,  1 D,  1 E,  1 F,  1 G,  1 H,  1 J,  1 K,  1 L,  1 M,  1 N,  1 P,  1 Q,  1 R,  1 S,  1 T wireless power transmission device, 
               2 ,  2 J power transmission radio wave (radio wave), 
               2 E element radio wave 
               2 E p  element radio wave radiated by element antenna  8   p    
               3  power reception device, 
               4 ,  4 J pilot signal, 
               5  pilot transmitter, 
               6 ,  6   2  pilot antenna, 
               7 ,  7 C,  7 D,  7   2  arrival direction detecting device, 
               8  element antenna, 
               9 ,  9 J element module, 
               9 P first-stage element module, 
               9 S second-stage element module, 
               10 ,  10 A,  10 B,  10 C,  10 D,  10 E,  10 F,  10 G,  10 H,  10 J,  10 K,  10 L,  10 M,  10 N,  10 P,  10 Q,  10 R,  10 S,  10 T control device, 
               11  transmission signal generator, 
               12  distribution circuit, 
               13  phase shifter, 
               14  amplifier, 
               15  time device, 
               16  time device, 
               17  monitor antenna (measurement antenna), 
               18  detector (radio wave measurer), 
               19 ,  19 E,  19 F,  19 J,  19 Q on-board control device, 
               20  movable body communication device, 
               21 ,  21 E,  21 F data storage device, 
               22  pilot antenna mount, 
               23  pilot antenna controller, 
               24  pilot receiver (presence direction determiner), 
               24 J pilot receiver (presence direction determiner, movable body position determiner), 
               25 ,  25 A,  25 F,  25 G,  25 H,  25 J,  25 N,  25 P,  25 Q data storage, 
               25 E,  25 M data storage (movable body data storage), 
               25 K,  25 L data storage (installation location data storage), 
               25 R data storage (movable body data storage, movable body position history storage, attitude data history storage), 
               25 S data storage (movable body position history storage, power reception device position history storage), 
               26  REV method necessary or unnecessary determiner, 
               27 ,  27 A,  28 C,  28 H REV method executor (REV method phase controller), 
               28 ,  28 C,  28 H data acquisition command generator, 
               29 ,  29 G,  29 H element electric field calculator (REV method analyzer), 
               30  communication device (power transmitting-side communication device), 
               31  phase offset value calculator (phase reference adjuster), 
               32  phase offset value setter (phase reference adjuster), 
               33 ,  33 B,  33 C,  33 E,  33 T radiation direction determiner, 
               33 S radiation direction determiner (presence direction determiner), 
               34 ,  34 A,  34 E radio wave radiation controller (radiation direction changer), 
               34 J radio wave radiation controller (radiation direction changer, radiation target position changer), 
               35 ,  35 G measurement data analyzer, 
               36 ,  36 H operation phase shift amount acquirer, 
               37 ,  37 H element electric field vector calculator, 
               38  azimuth mount controller, 
               39  signal strength meter, 
               40  positioning sensor, 
               41  movable body position determiner (presence direction determiner, power reception device position determiner), 
               42  laser positioning device (movable body position measuring device), 
               43 ,  43   1 ,  43   2 ,  43   3  laser beam, 
               44 ,  44   1 ,  44   2 ,  44   3  reflected laser beam, 
               45  pulse modulation switch, 
               46  distance meter (movable body distance measurer, movable body position determiner), 
               47 ,  47 K,  47 L,  47 N radiation target position determiner, 
               47 K,  47 L radiation target position determiner (movable body position determiner, presence direction determiner, movable body distance measurer), 
               47 M radiation target position determiner (movable body position determiner, presence direction determiner, movable body distance measurer, power reception device position determiner), 
               48   1 ,  48   2 ,  48   3  laser distance measuring instrument (distance measuring instrument, movable body position measuring device), 
               49 ,  49 S movable body position predictor (power reception device position predictor), 
               49 T arrival direction predictor (presence direction predictor), 
               50 ,  50 A,  50 B,  50 J power transmission antenna (phased array antenna), 
               51  power transmission antenna unit, 
               52  azimuth rotating mount, 
               53  distance measurement signal, 
               54  distance measurement response signal, 
               55  predicted movable body position, 
               56  predicted arrival direction data, 
               60 ,  60 E,  60 F,  60 G,  60 H,  60 J,  60 M,  60 Q movable body, 
               61  detector controller, 
               62  detection data time adder, 
               63 ,  63 C,  63 H data acquisition command interpreter, 
               64 ,  64 C transmission data generator, 
               65  positioning sensor, 
               66  attitude sensor, 
               67  movable body position sender, 
               68  pulse modulation manager, 
               68 Q distance measurement communication manager, 
               69  attitude data sender, 
               70 ,  70 C measurement period data 
               71  detection data (received radio wave data, REV method run-time radio wave data), 
               72  time data, 
               73 ,  73 C,  73 H data acquisition command, 
               74 ,  74 A,  74 C,  74 H REV method scenario, 
               75  phase operation data, 
               76  element electric field vector, 
               77  phase offset value, 
               78 ,  78   2 ,  78 T arrival direction data, 
               79  radiation direction data, 
               80  radiation command value, 
               81 ,  81 F,  81 R,  81 S movable body position, 
               82 ,  82 R attitude data, 
               83  movable body structure data, 
               84  power transmission device position (power transmission antenna position), 
               85 ,  85 F,  85 S power reception device position, 
               85 R predicted power reception device position, 
               86  maximum/minimum time, 
               87  maximum/minimum amplitude value, 
               88  REV method start time, 
               89  pulse modulation detection signal, 
               90  period while REV method is being executed, 
               91  movable body direction, 
               92 ,  92 A power transmission direction, 
               93 ,  93 A received power strength, 
               94  radiation target position data, 
               95  pulse transmission time, 
               96  pulse reception time, 
               95 Q distance measurement transmission time, 
               96 Q distance measurement reception time, 
               97 ,  97   1 ,  97   2 ,  97   3  target position distance data, 
               98  pilot antenna position (pilot antenna installation location data) 
               99  distance measuring instrument position (distance measuring instrument installation location data).