Patent Publication Number: US-10763979-B2

Title: Antenna apparatus and measurement method

Description:
TECHNICAL FIELD 
     The present invention relates to an antenna apparatus and a measurement method for measuring the transmission and reception characteristics of a device under test using a plurality of measurement antennas using an anechoic box in an over the air (OTA) environment. 
     BACKGROUND ART 
     In recent years, with the development of multimedia, wireless terminals (smartphones and the like) in which an antenna for wireless communication, such as cellular and wireless LAN, is mounted are being actively produced. In the future, in particular, there is a demand for a wireless terminal that transmits and receives radio signals corresponding to IEEE 802.11ad, 5G cellular, and the like that use broadband signals in a millimeter wave band. 
     In a wireless terminal manufacturing plant, a performance test is performed in which the output level or the reception sensitivity of the transmission radio wave defined for each communication standard is measured for a wireless communication antenna provided in a wireless terminal to determine whether or not a predetermined standard is satisfied. 
     With the transition of generation from 4G or 4G advance to 5G a test method for the performance test described above is also changing. For example, in a performance test in which a wireless terminal for 5G new radio system (NR system) (hereinafter, a 5G wireless terminal) is a device under test (DUT), cable connection between the antenna terminal of the DUT and a testing device, which is a mainstream in tests of 4G 4G advance, and the like, cannot be used. For this reason, a so-called OTA test is performed in which the DUT is housed in a box, which is not influenced by the surrounding radio wave environment, together with a test antenna and transmission of a test signal from the test antenna to the DUT and reception of a measurement target signal from the DUT, which has received the test signal, by the test antenna are performed by wireless communication. 
     In the performance test of the 5G wireless terminal, a compact antenna test range (hereinafter, a CATR) is known as test equipment for realizing the OTA test environment described above. The CATR includes an anechoic box called an OTA chamber, and houses the DUT and the test antenna so that intrusion of radio waves from the outside and radiation of radio waves to the outside are prevented. In addition, in the CATR, a reflector having a paraboloid of revolution is arranged in the signal propagation path between the antenna of the DUT and the test antenna. Therefore, since the signal propagation path can be shortened compared with a case where no reflector is used, the CATR is characterized in that compactness can be literally realized compared with the OTA test in a general far-field environment. 
     In a measurement apparatus using the CATR, a test signal is transmitted from the test antenna to be received by the DUT in the OTA chamber, and a measurement target signal transmitted from the DUT that has received the test signal is received by the test antenna and the performance test described above is performed. 
     On the other hand, the 5G wireless terminal has a wide use frequency range. For this reason, in a case where the 5G wireless terminal cannot be covered by one test antenna at the time of measurement in a state in which the 5G wireless terminal is housed as a DUT in the CATR, it is necessary to prepare a plurality of test antennas that use a plurality of different frequency bands within the usable frequency range. 
     As a conventional antenna measurement apparatus using a plurality of test antennas, there is known a technique for simultaneously transmitting a plurality of beams with the same frequency, on which different codes are superimposed, through a multi-beam antenna and simultaneously measuring all beams radiated from the multi-beam antenna while suppressing the influence of unnecessary waves due to encoding on the plurality of beams with the same frequency (for example, refer to Patent Document 1). 
     RELATED ART DOCUMENT 
     Patent Document 
     [Patent Document 1] JP-A-2009-147687 
     DISCLOSURE OF THE INVENTION 
     Problem that the Invention is to Solve 
     In the above-described conventional measurement apparatus using the CATR and the plurality of test antennas, in the case of measuring the transmission and reception characteristics of the DUT for each frequency band used by each test antenna, it is necessary to manually replace the test antennas one by one at the focal position of the reflector in the anechoic box. In this case, it is necessary to secure a place for storing the plurality of test antennas in the anechoic box, and it takes time and effort to take out one test antenna from the place and install the test antenna at the focal position. This causes an increase in the size of the anechoic box. In addition, a complicated work for replacement of the test antenna is required. In addition, in this type of conventional measurement apparatus, since the measurement is unavoidably interrupted at the time of replacement of each test antenna, and the measurement processing also becomes complicated. 
     In addition, although Patent Document 1 discloses a technique for reflecting radio waves radiated from each antenna forming a multi-beam antenna on a mirror surface and measuring the radio waves and a technique for rotating each antenna, each antenna could not be switched to the focal position of the mirror surface. In addition, Patent Document 1 discloses rotating each antenna merely to change the position of each antenna, but each antenna is not sequentially arranged at the focal position of the mirror surface. 
     The present invention has been made to solve such conventional problems, and it is an object of the present invention to provide an antenna apparatus and a measurement method capable of efficiently measuring the transmission and reception characteristics for frequency bands corresponding to a plurality of test antennas to be tested while avoiding an increase in the size of an anechoic box and the complication of a work for replacement of the test antennas. 
     Means for Solving the Problem 
     In order to solve the aforementioned problem, an antenna apparatus according to a first aspect of the present invention includes: an anechoic box having an internal space that is not influenced by a surrounding radio wave environment; a reflector that is housed in the internal space and has a predetermined paraboloid of revolution, radio signals transmitted or received by an antenna to be tested of a device under test being reflected through the paraboloid of revolution; a plurality of antennas corresponding to radio signals in a plurality of measurement target frequency bands for measuring transmission and reception characteristics of the device under test; and antenna arrangement means for sequentially arranging the plurality of antennas at a focal position, which is determined from the paraboloid of revolution, according to the measurement target frequency bands. 
     With this configuration, in the antenna apparatus according to the first aspect of the present invention, since the antenna arrangement means is provided in the anechoic box, the user does not need to perform a work for sequential replacement of the plurality of antennas at the focal position of the reflector during the measurement of the transmission and reception characteristics of a device under test (DUT). In addition, since the antenna arrangement means is added after shortening the signal propagation path by providing the reflector, this is not a major obstacle for the anechoic box to be made compact. In addition, since the measurement of the transmission and reception characteristics of the device under test for each measurement target frequency band can be performed without interruption while reducing the time and effort for arranging each antenna at the focal position, the efficiency of the measurement processing can be improved. 
     In an antenna apparatus according to a second aspect of the present invention, the antenna to be tested uses a radio signal in a specified frequency band. A simulation measurement apparatus is further provided that, each time one of the plurality of antennas is arranged at the focal position, outputs a test signal to the device under test through the antenna arranged at the focal position, receives a measurement target signal output from the device under test to which the test signal has been input through the antenna arranged at the focal position, and measures transmission and reception characteristics of the device under test for the measurement target frequency band, which is used by the antenna arranged at the focal position, based on the received measurement target signal. 
     With this configuration, the antenna apparatus according to the second aspect of the present invention can smoothly measure the transmission and reception characteristics of the DUT, which has an antenna to be tested that uses a radio signal in a specified frequency band, without much time and effort for replacement of the test antenna for frequency bands of a plurality of different frequency band groups in the specified frequency band. 
     In an antenna apparatus according to a third aspect of the present invention, the specified frequency band is a 5G NR band, and each of the plurality of measurement target frequency bands is a frequency band of any one of frequency band groups of a group of n77, n78, and n79, a group of n258 and n257, and a group of n259 that are a plurality of different frequency band groups in the specified frequency band. 
     With this configuration, the antenna apparatus according to the third aspect of the present invention can smoothly measure the transmission and reception characteristics of the DUT (5G wireless terminal), which has an antenna to be tested that uses a radio signal in the 5G NR band, without much time and effort for replacement of the test antenna for a frequency band of any one of frequency band groups of a group of n77, n78, and n79, a group of n258 and n257, and a group of n259. 
     In an antenna apparatus according to a fourth aspect of the present invention, the antenna arrangement means operates automatically, and includes: an antenna holding mechanism that is provided in the internal space of the anechoic box such that each of the antennas is arranged on a circumference around a rotary shaft in a rotating body rotatable with the rotary shaft as a center, the focal position is located on the circumference, and each of the antennas passes through the focal position by rotation of the rotating body; a power unit having a driving motor for rotationally driving the rotating body through the rotary shaft; and an automatic antenna arrangement control unit that controls the driving motor such that each of the antennas is sequentially stopped at the focal position according to the measurement target frequency bands. 
     With this configuration, since the antenna apparatus according to the fourth aspect of the present invention adopts the antenna holding mechanism in which each antenna is arranged on the circumference around the rotary shaft for the rotating body rotatable with the rotary shaft as the center, it is possible to reduce the installation space of the antenna holding mechanism while keeping the anechoic box compact. 
     In an antenna apparatus according to a fifth aspect of the present invention, the antenna holding mechanism is provided on a bottom surface of the internal space of the anechoic box, and is formed by the rotating body rotatable along a plane in a horizontal direction by the rotary shaft along a vertical direction. 
     With this configuration, in the antenna apparatus according to the fifth aspect of the present invention, a space horizontal to the bottom surface of the internal space of the anechoic box is secured as an installation space of the antenna holding mechanism. Therefore, it is possible to prevent an increase in the height of the anechoic box. 
     In an antenna apparatus according to a sixth aspect of the present invention, the antenna holding mechanism holds each of the antennas such that a receiving surface of each of the antennas is directed to the rotary shaft side. 
     With this configuration, in the antenna apparatus according to the sixth aspect of the present invention, the antenna holding mechanism is arranged at the central portion of the bottom surface of the internal space of the anechoic box. Therefore, since the diameter of the circumference on which each antenna is arranged can be reduced, it is possible to keep the antenna holding mechanism and the anechoic box compact. 
     In an antenna apparatus according to a seventh aspect of the present invention, the antenna holding mechanism holds each of the antennas such that a receiving surface of each of the antennas is directed to an opposite side to the rotary shaft side. 
     With this configuration, in the antenna apparatus according to the seventh aspect of the present invention, the antenna holding mechanism is arranged at a position near the side surface avoiding the central portion of the bottom surface of the internal space of the anechoic box. Therefore, since the diameter of the circumference on which each antenna is arranged can be reduced, it is possible to keep the antenna holding mechanism and the anechoic box compact. 
     In an antenna apparatus according to an eighth aspect of the present invention, in a case where each of the antennas is stopped at the focal position, the antenna holding mechanism holds the antenna so as to face the reflector at an angle at which a receiving surface of the antenna is perpendicular to a beam axis of the radio signal. 
     With this configuration, in the antenna apparatus according to the eighth aspect of the present invention, it is possible to improve the reception accuracy of each antenna arranged at the focal position of the reflector and improve the measurement accuracy of the transmission and reception characteristics of the DUT. 
     In an antenna apparatus according to a ninth aspect of the present invention, the antenna holding mechanism is provided on a bottom surface of the internal space of the anechoic box, and is formed by the rotating body rotatable along a plane in a vertical direction by the rotary shaft along a horizontal direction. 
     With this configuration, in the antenna apparatus according to the ninth aspect of the present invention, a space perpendicular to the bottom surface of the internal space of the anechoic box is secured as an installation space of the antenna holding mechanism. Therefore, it is possible to prevent an increase in the width of the anechoic box. 
     In an antenna apparatus according to a tenth aspect of the present invention, the antenna arrangement means includes: an antenna holding mechanism that has a first slide mechanism that holds a plurality of antenna pedestals, on which the antennas are provided, so as to be slidable in one direction while maintaining a predetermined interval and a second slide mechanism that slidably holds the first slide mechanism in the other direction perpendicular to the one direction through a pedestal portion and that is provided in the internal space of the anechoic box such that each of the antennas is able to pass through the focal position; a power unit that includes a first driving motor for rotationally driving a first driving shaft for sliding each of the antenna pedestals in the one direction and a second driving motor for rotationally driving a second driving shaft for sliding the pedestal portion in the other direction; and an automatic antenna arrangement control unit that controls the first and second driving motor such that each of the antennas is sequentially stopped at the focal position according to the measurement target frequency bands. 
     With this configuration, in the antenna apparatus according to the tenth aspect of the present invention, a space horizontal to the bottom surface of the internal space of the anechoic box is secured as an installation space of the antenna holding mechanism. Therefore, it is possible to prevent an increase in the height of the anechoic box. In addition, since the antennas slide in directions perpendicular to each other on the horizontal plane, stable movement toward the focal position is possible. 
     In an antenna apparatus according to an eleventh aspect of the present invention, a plurality of the first slide mechanisms are provided so as to be parallel to the one direction and be spaced apart from each other by a predetermined distance in the other direction, and the power unit includes the first driving motor corresponding to each of the first slide mechanisms. 
     With this configuration, the antenna apparatus according to the eleventh aspect of the present invention can easily cope with the addition of each antenna while avoiding an increase in the size of the anechoic box by making full use of the space in the horizontal direction on the bottom surface of the anechoic box. 
     In an antenna apparatus according to a twelfth aspect of the present invention, the antenna arrangement means operates automatically, and includes: an antenna holding mechanism that is provided in the internal space of the anechoic box such that each of the antennas is arranged on a circumference around a rotary shaft in a rotating body rotatable with the rotary shaft as a center, the focal position is located on the circumference, and each of the antennas passes through the focal position by rotation of the rotating body; a power unit having a driving motor for rotationally driving the rotating body through the rotary shaft; and an automatic antenna arrangement control unit that controls the driving motor such that each of the antennas is sequentially stopped at the focal position according to the measurement target frequency bands. 
     In an antenna apparatus according to a thirteenth aspect of the present invention, the antenna arrangement means operates automatically, and includes: an antenna holding mechanism that is provided in the internal space of the anechoic box such that each of the antennas is arranged on a circumference around a rotary shaft in a rotating body rotatable with the rotary shaft as a center, the focal position is located on the circumference, and each of the antennas passes through the focal position by rotation of the rotating body; a power unit having a driving motor for rotationally driving the rotating body through the rotary shaft; and an automatic antenna arrangement control unit that controls the driving motor such that each of the antennas is sequentially stopped at the focal position according to the measurement target frequency bands. 
     In an antenna apparatus according to a fourteenth aspect of the present invention, the antenna holding mechanism holds each of the antennas such that a receiving surface of each of the antennas is directed to the rotary shaft side. 
     In an antenna apparatus according to a fifteenth aspect of the present invention, the antenna holding mechanism holds each of the antennas such that a receiving surface of each of the antennas is directed to an opposite side to the rotary shaft side. 
     In an antenna apparatus according to a sixteenth aspect of the present invention, in a case where each of the antennas is stopped at the focal position, the antenna holding mechanism holds the antenna so as to face the reflector at an angle at which a receiving surface of the antenna is perpendicular to a beam axis of the radio signal. 
     In an antenna apparatus according to a seventeenth aspect of the present invention, in a case where each of the antennas is stopped at the focal position, the antenna holding mechanism holds the antenna so as to face the reflector at an angle at which a receiving surface of the antenna is perpendicular to a beam axis of the radio signal. 
     In an antenna apparatus according to an eighteenth aspect of the present invention, in a case where each of the antennas is stopped at the focal position, the antenna holding mechanism holds the antenna so as to face the reflector at an angle at which a receiving surface of the antenna is perpendicular to a beam axis of the radio signal. 
     In an antenna apparatus according to a nineteenth aspect of the present invention, the antenna holding mechanism is provided on a bottom surface of the internal space of the anechoic box, and is formed by the rotating body rotatable along a plane in a vertical direction by the rotary shaft along a horizontal direction. 
     A measurement method according to a twentieth aspect of the present invention is a measurement method using the antenna apparatus according to any one of the first to nineteenth aspects, and includes: a holding step of holding the device under test in a device under test holding unit in the anechoic box; an antenna arrangement step of sequentially arranging the plurality of antennas at the focal position according to the measurement target frequency bands based on a predetermined measurement start command; a test signal output step of causing the simulation measurement device to output a test signal to the device under test through the antenna arranged at the focal position; a signal receiving step of receiving a measurement target signal, which is output from the device under test to which the test signal has been input, through the antenna arranged at the focal position; and a measurement step of measuring transmission and reception characteristics of the device under test for a radio signal in the measurement target frequency band, which is used by the antenna arranged at the focal position, based on the measurement target signal received in the signal receiving step. 
     With this configuration, since the measurement method according to the twentieth aspect of the present invention uses the antenna apparatus having an anechoic box in which antenna arrangement means is provided, the user does not need to perform a work for sequential replacement of the plurality of antennas at the focal position of the reflector during the measurement of the transmission and reception characteristics of the device under test. In addition, since the antenna arrangement means is added after shortening the signal propagation path by providing the reflector, this is not a major obstacle for the anechoic box to be made compact. In addition, since the measurement of the transmission and reception characteristics of the device under test for each measurement target frequency band can be performed without interruption while reducing the time and effort for arranging each antenna, the efficiency of the measurement processing can be improved. 
     [Advantage of the Invention] 
     The present invention can provide an antenna apparatus and a measurement method capable of efficiently measuring the transmission and reception characteristics for frequency bands corresponding to a plurality of test antennas to be tested while avoiding an increase in the size of an anechoic box and the complication of a work for replacement of the test antennas. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram showing the schematic configuration of the entire measurement apparatus according to a first embodiment of the present invention. 
         FIG. 2  is a block diagram showing the functional configuration of the measurement apparatus according to the first embodiment of the present invention. 
         FIG. 3  is a block diagram showing the functional configuration of an integrated control device of the measurement apparatus according to the first embodiment of the present invention. 
         FIG. 4  is a block diagram showing the functional configuration of an NR system simulator in the measurement apparatus according to the first embodiment of the present invention. 
         FIGS. 5A and 5B  are schematic diagrams illustrating a near field and a far field in radio wave propagation between an antenna AT and a wireless terminal. 
         FIG. 6  is a schematic diagram showing the signal path structure of a parabola having the same paraboloid of revolution as a reflector adopted in an OTA chamber of the measurement apparatus according to the first embodiment of the present invention. 
         FIG. 7  is a schematic diagram showing the signal path structure of an offset parabola having the same paraboloid of revolution as a reflector adopted in an OTA chamber of the measurement apparatus according to the first embodiment of the present invention. 
         FIG. 8  is a table showing the use frequency classification of a plurality of test antennas for measurement of the transmission and reception characteristics of a DUT adopted in an OTA chamber of the measurement apparatus according to the first embodiment of the present invention. 
         FIGS. 9A and 9B  are conceptual diagrams showing the arrangement of test antennas in automatic antenna arrangement means of the measurement apparatus according to the first embodiment of the present invention. 
         FIG. 10  is a flowchart showing a process of measuring the transmission and reception characteristics of a DUT in the measurement apparatus according to the first embodiment of the present invention. 
         FIG. 11  is a side view showing the schematic configuration of automatic antenna arrangement means adopted in an OTA chamber of a measurement apparatus according to a second embodiment of the present invention. 
         FIGS. 12A and 12B  are schematic configuration diagrams of automatic antenna arrangement means adopted in an OTA chamber of a measurement apparatus according to a third embodiment of the present invention. 
         FIG. 13  is a perspective view showing the schematic configuration of automatic antenna arrangement means adopted in an OTA chamber of a measurement apparatus according to a fourth embodiment of the present invention. 
     
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     Hereinafter, embodiments of a measurement apparatus and a measurement method according to the present invention will be described with reference to the diagrams. 
     First Embodiment 
     First, the configuration of a measurement apparatus  1  according to a first embodiment of the present invention will be described with reference to  FIGS. 1 to 9 . The measurement apparatus  1  corresponds to an antenna apparatus of the present invention. The measurement apparatus  1  according to the present embodiment has an appearance structure shown in  FIG. 1  as a whole, and is configured by functional blocks as shown in  FIG. 2 .  FIG. 1  shows the arrangement of components in a state in which an OTA chamber  50  is seen through from the side surface. 
     As shown in  FIGS. 1 and 2 , the measurement apparatus  1  according to the present embodiment has an integrated control device  10 , an NR system simulator  20 , a signal processing unit  40 , and the OTA chamber  50 . 
     The integrated control device  10  is communicably connected to the NR system simulator  20  through a network  19 , such as Ethernet (registered trademark). In addition, the integrated control device  10  is also connected to control target elements in the OTA chamber  50  through the network  19 . The measurement apparatus  1  has an automatic antenna arrangement control unit  16  and a DUT posture control unit  17  as control target elements in the OTA chamber  50 . 
     The integrated control device  10  performs overall control of control target elements in the NR system simulator  20  and the OTA chamber  50  through the network  19 , and is, for example, a personal computer (PC). The automatic antenna arrangement control unit  16  and the DUT posture control unit  17  may be provided in the integrated control device  10 , for example, as shown in  FIG. 3 . The following explanation will be given on the assumption that the integrated control device  10  has a configuration shown in  FIG. 3 . 
     The measurement apparatus  1  is operated, for example, in a state in which each component is mounted on each rack  90   a  using a rack structure  90  having a plurality of racks  90   a  shown in  FIG. 1 . In  FIG. 1 , an example is mentioned in which the integrated control device  10 , the NR system simulator  20 , and the OTA chamber  50  are mounted on each rack  90   a  of the rack structure  90 . 
     Here, for the sake of convenience, the configuration of the OTA chamber  50  will be described first. The OTA chamber  50  realizes an OTA test environment in testing the performance of a 5G wireless terminal, and is used as an example of the CATR described above. 
     As shown in  FIGS. 1 and 2 , for example, the OTA chamber  50  is formed by a metal housing main body  52  having a rectangular parallelepiped internal space  51 . In the internal space  51 , a DUT  100  and a plurality of test antennas  6  that can face an antenna  110  of the DUT  100  are housed so that intrusion of radio waves from the outside and radiation of radio waves to the outside are prevented. In the internal space  51  of the OTA chamber  50 , the reflector  7  for realizing a radio wave path for returning the radio signal radiated from the antenna  110  of the DUT  100  to the light receiving surface of the test antenna  6  is arranged. A plurality of test antennas  6  configures a plurality of antennas in the present invention. In addition, a radio wave absorber  55  is bonded to the entire inner surface of the OTA chamber  50 , that is, the entire bottom surface  52   a , side surface  52   b , and upper surface  52   c  of the housing main body  52 , so that a function of restricting the radiation of radio waves to the outside is strengthened. Thus, the OTA chamber  50  realizes an anechoic box having the internal space  51  that is not influenced by surrounding radio wave environment. The anechoic box used in the present embodiment is of an anechoic type, for example. 
     The DUT  100  to be tested is, for example, a wireless terminal such as a smartphone. As a communication standard of the DUT  100 , cellular (LTE, LTE-A, W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, 1×EV-DO, TD-SCDMA, and the like), wireless LAN (IEEE 802.11b/g/a/n/ac/ad and the like), Bluetooth (registered trademark), GNSS (GPS, Galileo, GLONASS, BeiDou, and the like), FM, and digital broadcasting (DVB-H, ISDB-T, and the like) can be mentioned. In addition, the DUT  100  may also be a wireless terminal that transmits and receives radio signals in a millimeter wave band corresponding to IEEE 802.11ad, 5G cellular, and the like. 
     In the present embodiment, the DUT  100  is a 5G NR wireless terminal. For the 5G NR wireless terminal, the 5G NR standard specifies that a predetermined frequency band (refer to “5G NR band” in  FIG. 8 ) including the millimeter wave band and other frequency bands used in LTE and the like is a communicable frequency range. In short, the antenna  110  of the DUT  100  uses a radio signal in a predetermined frequency band (5G NR band). The antenna  110  of the DUT  100  corresponds to an antenna to be tested in the present invention. 
     The 5G NR wireless terminal having the communicable frequency range described above is set to be able to communicate using any one of the bands identified by the numbers 1, 2, and 3 in the table shown in  FIG. 8 , for example, at the time of shipment, and thereafter, the usable frequency band can be switched by a predetermined setting change operation. In such a wireless terminal, a band set to be usable may be referred to as an in-band, and a band that is not set to be usable may be referred to as an out-band. In the case of measuring the transmission and reception characteristics in the OTA environment in the OTA chamber  50  using the wireless terminal as the DUT  100 , measurement is required for all the bands of the in-band and the out-band described above. 
       FIG. 8  is a table showing the usable frequency range classification of the three test antennas  6  arranged in the OTA chamber  50  according to the present embodiment. As shown in  FIG. 8 , three frequency bands identified by the numbers 1, 2, and 3 are assigned to 3.3 MHz to 5.0 MHz, 24.25 MHz to 40.0 MHz, and 40.5 MHz to 43.5 MHz, respectively. The frequency bandwidth (3.3 MHz to 5.0 MHz) assigned to the number 1 corresponds to a group of frequency bandwidths (frequency band group) including, for example, frequency bands of n77, n78, and n79 in the known 5G NR band list defined by 3rd generation partnership project (3GPP). Similarly, the frequency bandwidth of 24.25 MHz to 29.5 MHz assigned to the number 2 and the frequency bandwidth of 40.5 MHz to 43.5 MHz assigned to the number 3 correspond to a group of frequency bandwidths including frequency bands of n258 and n260 and a group of frequency bandwidths including a frequency band of n259 defined in the band list, respectively, for example. 
     In the present embodiment, in the OTA chamber  50 , for example, three test antennas  6  using frequency bands corresponding to the numbers 1, 2, and 3 in the frequency band classification shown in  FIG. 8  are arranged in the internal space  51 . The three test antennas  6  are automatically arranged one by one in order at the focal position (indicated by reference symbol F in  FIG. 1 ) of the reflector  7  by the automatic antenna arrangement means  60 . On the other hand, the DUT  100  according to the present embodiment is configured to be able to selectively set the frequency bands corresponding to the numbers 1, 2, and 3 as usable frequency bands. During measurement regarding transmission and reception in the OTA chamber  50 , the DUT  100  can transmit and receive a test signal and a measurement target signal through the test antennas  6  sequentially arranged at the focal position F using the frequency bands corresponding to the numbers 1, 2, and 3 in order. 
     Next, the arrangement of the DUT holding unit  56 , the test antenna  6 , and the reflector  7  in the internal space  51  of the OTA chamber  50  will be described. In the OTA chamber  50 , a DUT holding unit  56  extending in a vertical direction is provided on the bottom surface  52   a  of the housing main body  52  in the internal space  51 . The DUT holding unit  56  has a driving unit  56   a  provided on the bottom surface  52   a , a support stand  56   b  connected to the driving unit  56   a , and a DUT mounting unit  56   c  extending in a horizontal direction from the side surface of the support stand  56   b . The driving unit  56   a  is formed by, for example, a two-axis positioner including a rotation mechanism that rotates in two axial directions. Hereinafter, the driving unit  56   a  may be referred to as a two-axis positioner (refer to  FIG. 3 ). Therefore, the DUT holding unit  56  can rotate the DUT  100  held by the DUT mounting unit  56   c  so as to be located at the center of the sphere and to be able to sequentially change the posture to a state in which the antenna  110  is directed to all points on the surface of the sphere, for example. 
     In the OTA chamber  50 , the antenna holding mechanism  61  is provided at a position below the bottom surface  52   a  of the housing main body  52 , and the antenna holding mechanism  61  holds the plurality of test antennas  6  in a state in which the plurality of test antennas  6  are spaced apart from each other. In the present embodiment, the antenna holding mechanism  61  holds the three test antennas  6  capable of transmitting and receiving radio signals in the three measurement target frequency bands identified by the numbers 1 to 3 in the table shown in  FIG. 8 , for example. 
     The antenna holding mechanism  61  is attached to the bottom surface  52   a  in the internal space  51  of the OTA chamber  50  through a power unit  64 . The antenna holding mechanism  61  forms automatic antenna arrangement means  60  together with the power unit  64  and the automatic antenna arrangement control unit  16  (refer to  FIG. 2 ). The automatic antenna arrangement means  60  forms antenna arrangement means of the present invention. The configuration of the automatic antenna arrangement means  60  will be described in detail later. 
     In the OTA chamber  50 , the reflector  7  has an offset parabola (refer to  FIG. 7 ) type structure to be described later. As shown in  FIG. 1 , the reflector  7  is attached to a required position of the side surface  52   b  of the OTA chamber  50  using a reflector holder  58 . The reflector  7  is arranged at a position and posture at which a test signal radiated from one test antenna  6  arranged at the focal position F of the paraboloid of revolution can be received on the paraboloid of revolution and reflected toward the DUT  100  held by the DUT holding unit  56  and the DUT  100  having received the test signal can receive a measurement target signal radiated from the antenna  110  on the paraboloid of revolution and reflect the measurement target signal toward the test antenna  6  from which the test signal has been radiated. In the present embodiment, as the test antenna  6  for transmitting and receiving the test signal and the measurement target signal described above, three test antennas  6  held by the antenna holding mechanism  61  are automatically arranged at the focal position F one by one in order by the automatic antenna arrangement means  60 . 
     Here, the merit of mounting the reflector  7  in the OTA chamber  50  and the preferable form of the reflector  7  will be described with reference to  FIGS. 5A to 7 .  FIGS. 5A and 5B  are schematic diagrams showing how radio waves radiated from an antenna AT equivalent to the test antenna  6  are transmitted to a wireless terminal  100 A, for example. The wireless terminal  100 A corresponds to the DUT  100 .  FIG. 5A  shows an example of a case where radio waves are directly transmitted from the antenna AT to the wireless terminal  100 A (Direct FAR Field), and  FIG. 5B  shows an example of a case where radio waves are transmitted from the antenna AT to the wireless terminal  100 A through a reflecting mirror  7 A having a paraboloid of revolution. 
     As shown in  FIG. 5A , a radio wave having the antenna AT as a radiation source has a feature that the radio wave propagates while the wavefront spreads spherically with the radiation source at the center. In addition, it is known that a surface (wavefront) obtained by connecting the in-phase points of the waves is a curved spherical surface (spherical wave) at a short distance from the radiation source, but the wavefront becomes close to a plane (plane wave) as the distance from the radiation source increases. In general, a region where the wavefront needs to be considered as a spherical surface is called a near field (NEAR FIELD), and a region where the wavefront may be considered as a plane is called a far field (FAR FIELD). In the propagation of radio waves shown in  FIG. 5A , it is preferable that the wireless terminal  100 A receives a plane wave rather than receiving a spherical wave in order to perform satisfactory reception. 
     In order to receive a plane wave, the wireless terminal  100 A needs to be provided so as to exist in the far field. Here, assuming that the maximum linear size of the wireless terminal  100 A is D and the wavelength is λ, the far field is a distance of 2D 2 /λ, or more from the antenna AT. Specifically, in the case of D=0.4 meters (m) and wavelength λ=0.01 m (corresponding to a radio signal in a 28 GHz band), the position of approximately 30 m from the antenna AT is a boundary between the near field and the far field, and it is necessary to place the wireless terminal  100 A at a position farther from the boundary. In the present embodiment, measurement of the DUT  100  whose maximum linear size D is, for example, about 5 cm (centimeters) to about 33 cm is assumed. 
     Thus, the Direct Far Field method shown in  FIG. 5A  has a feature that the propagation distance between the antenna AT and the wireless terminal  100 A is large and the propagation loss is large. Therefore, as a countermeasure, for example, as shown in  FIG. 5B , there is a method in which the reflecting mirror  7 A having a paraboloid of revolution is arranged at a position where the radio wave of the antenna AT can be reflected and introduced by the wireless terminal  100 A. According to this method, not only can the distance between the antenna AT and the wireless terminal  100 A be shortened, but also the region of the plane wave spreads from the distance immediately after reflection on the mirror surface of the reflecting mirror  7 A. Therefore, the reduction effect of the propagation loss can also be expected. The propagation loss can be expressed by the phase difference between the waves in phase. The phase difference that can be allowed as a propagation loss is, for example, λ/16. The phase difference is assumed to be evaluated by, for example, a vector network analyzer (VNA). 
     For example, a parabola (refer to  FIG. 6 ) or an offset parabola (refer to  FIG. 7 ) can be used as the reflecting mirror  7 A shown in  FIG. 5A . As shown in  FIG. 6 , the parabola has a mirror surface (paraboloid of revolution) that is symmetrical with respect to the axis passing through the antenna center O. By providing a primary radiator, which has directivity in the direction of the paraboloid of revolution, at the focal position F determined from the paraboloid of revolution, the parabola has a function of reflecting radio waves radiated from the primary radiator in a direction parallel to the axial direction. On the contrary, it can be understood that, by arranging, for example, the test antenna  6  according to the present embodiment at the focal position F, the parabola can reflect radio waves (for example, radio signal transmitted from the DUT  100 ) incident on the paraboloid of revolution in a direction parallel to the axial direction so that the radio waves are guided to the test antenna  6 . However, since the planar shape of the parabola viewed from the front (Z direction) is a perfect circle, the structure is large. For this reason, the parabola is not suitable for being arranged as the reflector  7  of the OTA chamber  50 . 
     On the other hand, as shown in  FIG. 7 , the offset parabola has a mirror surface that is asymmetric with respect to the axis of the paraboloid of revolution (a shape obtained by cutting out a part of the paraboloid of revolution of the perfect circle type parabola (refer to  FIG. 6 )). By providing a primary radiator with its beam axis inclined at an angle α, for example, with respect to the axis of the paraboloid of revolution, the offset parabola has a function of reflecting radio waves radiated from the primary radiator in a direction parallel to the axial direction of the paraboloid of revolution. It can be understood that, by arranging, for example, the test antenna  6  according to the present embodiment at the focal position F, the offset parabola can reflect radio waves (for example, a test signal with respect to the DUT  100 ) radiated from the test antenna  6  on the paraboloid of revolution in a direction parallel to the axial direction of the paraboloid of revolution and reflect radio waves (for example, a measurement target signal transmitted from the DUT  100 ) incident on the paraboloid of revolution in a direction parallel to the axial direction of the paraboloid of revolution so that the radio waves are guided to the test antenna  6 . Since the offset parabola can be arranged such that the mirror surface is almost vertical, the structure is much smaller than the parabola (refer to  FIG. 6 ). 
     Based on the findings described above, in the OTA chamber  50  according to the present embodiment, as shown in  FIG. 1 , the reflector  7  using the offset parabola (refer to  FIG. 7 ) is arranged in the radio wave propagation path between the DUT  100  and the test antenna  6 . The reflector  7  is attached to the side surface  52   b  of the housing main body  52  so that the position indicated by the reference numeral F in the diagram is the focal position. 
     The reflector  7  and one (arranged at the focal position) of the three test antennas  6  held by the antenna holding mechanism  61  are in an offset state in which the beam axis BS 1  of the test antenna  6  is inclined by a predetermined angle α with respect to the axis RS 1  of the reflector  7 . One test antenna  6  referred to herein is the test antenna  6  that can be viewed from the reflector  7  through an opening  67   a  of a cover unit  67  that covers the antenna holding mechanism  61 . 
     The reflector  7  has the focal position F on the beam axis BS 1  of the test antenna  6 , and each test antenna  6  held by a rotating body  62  of the antenna holding mechanism  61  can sequentially pass through the position of one test antenna  6  whose visibility can be secured as described above, that is, the focal position F of the reflector  7 . The inclination angle α described above can be set to, for example, 30°. In this case, the test antenna  6  is held by the antenna holding mechanism  61  so as to face the reflector  7  at an elevation angle of 30°, that is, so as to face the reflector  7  at an angle at which the receiving surface of the test antenna  6  is perpendicular to the beam axis of the radio signal. By adopting the offset parabola type reflector  7 , the reflector  7  itself can be made small. Therefore, since it is possible to arrange the reflector  7  in such a posture that the mirror surface is almost vertical, there is a merit that the structure of the OTA chamber  50  can be reduced. 
     Next, the configuration of the automatic antenna arrangement means  60  for sequentially arranging a plurality of test antennas  6  at the focal position F of the reflector  7  will be described in detail. 
     The automatic antenna arrangement means  60  mounted in the OTA chamber  50  has the antenna holding mechanism  61 , the power unit  64 , the cover unit  67 , and the automatic antenna arrangement control unit  16 , for example, as shown in  FIGS. 1 and 2 . The antenna holding mechanism  61  is formed by the rotating body  62  that can rotate around a rotary shaft  63 . In the rotating body  62 , for example, three test antennas  6  are arranged on the circumference around the rotary shaft  63 . 
     As a more specific example, for example, as shown in  FIG. 9A , in the rotating body  62 , the three test antennas  6  are arranged at equal intervals along the outer periphery of a circle Cl defining the circumference described above, that is, at intervals of 120° around the rotary shaft  63  on the horizontal plane. Here, the antenna holding mechanism  61  is provided in the internal space  51  so that the receiving surface of each test antenna  6 , which moves (rotates) in the circumferential direction on the circumference of the circle Cl by rotation of the rotating body  62 , passes through the focal position F of the reflector  7 . The three test antennas  6  used in the present embodiment can transmit and receive radio signals in respective frequency bands identified by the numbers 1 to 3 in the table shown in  FIG. 8 , for example. The arrangement of the three test antennas  6  on the circumference is not limited to the arrangement (number and separation angle) shown in  FIG. 9A . For example, as shown in  FIG. 9B , the three test antennas  6  may be arranged so as to be close to each other at intervals of 60° with the rotary shaft  63  as the center. In the present invention, it is needless to say that the number of test antennas  6  is not limited to three mentioned in the present embodiment and can be set to any number according to the allocation of in-bands and out-bands of the DUT  100  (refer to  FIG. 13 ). 
     The power unit  64  has a driving motor  65  for rotationally driving the rotating body  62  through the rotary shaft  63  and a connection member  66  such as a gear arranged between the driving motor  65  and the rotary shaft  63 . The cover unit  67  covers the antenna holding mechanism  61  and the power unit  64  so that intrusion of radio waves from the outside and radiation of radio waves to the outside can be restricted. 
     The opening  67   a  is formed in the cover unit  67 . The opening  67   a  is formed at a position, at which a view from the test antenna  6  with respect to the paraboloid of revolution of the reflector  7  can be secured, in a case where one of the test antennas  6  held by the antenna holding mechanism  61  is arranged at the focal position F of the reflector  7 . 
     The automatic antenna arrangement control unit  16  drives the driving motor  65  based on a command from a control unit  11  (refer to  FIG. 3 ) of the integrated control device  10  so that each test antenna  6  moves to the focal position F of the reflector  7  and stops in a sequential manner according to each measurement target frequency band identified by the numbers 1 to 3 in the table shown in  FIG. 8 , for example. 
     Here, the functional configuration of the measurement apparatus  1  according to the present embodiment will be described in more detail with reference to  FIGS. 2 to 4 . In the measurement apparatus  1  (refer to  FIG. 2 ) according to the present embodiment, the integrated control device  10  has, for example, a functional configuration shown in  FIG. 3 , and the NR system simulator  20  has, for example, a functional configuration shown in  FIG. 4 . The NR system simulator  20  forms a simulation measurement device of the present invention. 
     As shown in  FIG. 3 , the integrated control device  10  has the control unit  11 , an operation unit  12 , and a display unit  13 . The control unit  11  is, for example, a computer apparatus. For example, as shown in  FIG. 3 , the computer apparatus has: a central processing unit (CPU)  11   a  that performs predetermined information processing for realizing the function of the measurement apparatus  1  or overall control of the NR system simulator  20 ; a read only memory (ROM)  11   b  that stores an operating system (OS) for starting the CPU  11   a  or other programs, control parameters, and the like; a random access memory (RAM)  11   c  that stores the execution code, data, and the like of the OS or applications that the CPU  11   a  uses for operation; an external interface (I/F) unit  11   d  having an input interface function for receiving a predetermined signal and an output interface function for outputting a predetermined signal; a non-volatile storage medium such as a hard disk drive (not shown); and various input and output ports. The external I/F unit  11   d  is communicably connected to the NR system simulator  20  through the network  19 . In addition, the external I/F unit  11   d  is also connected to the driving motor  65  and the driving unit (two-axis positioner)  56   a  in the OTA chamber  50  through the network  19 . The operation unit  12  and the display unit  13  are connected to the input and output ports. The operation unit  12  is a functional unit that inputs various kinds of information, such as commands, and the display unit  13  is a functional unit that displays various kinds of information, such as an input screen for the various kinds of information and measurement results. 
     The computer apparatus described above functions as a control unit  11  by the CPU  11   a  that executes a program stored in the ROM  11   b  using the RAM  11   c  as a work area. As shown in  FIG. 3 , the control unit  11  has a call connection control unit  14 , a signal transmission and reception control unit  15 , the automatic antenna arrangement control unit  16 , and the DUT posture control unit  17 . The call connection control unit  14 , the signal transmission and reception control unit  15 , the automatic antenna arrangement control unit  16 , and the DUT posture control unit  17  are also realized by the CPU  11   a  that executes a predetermined program stored in the ROM  11   b  using the RAM  11   c  as a work area. 
     The call connection control unit  14  performs control to establish a call (a state in which radio signals can be transmitted and received) between the NR system simulator  20  and the DUT  100  by driving the test antenna  6 , which is automatically arranged at the focal position F of the reflector  7 , to transmit and receive a control signal (radio signal) to and from the DUT  100 . 
     The signal transmission and reception control unit  15  monitors a user operation in the operation unit  12 . In response to a predetermined measurement start operation for the measurement of the transmission and reception characteristics of the DUT  100  by the user, through the call connection control of the call connection control unit  14 , the signal transmission and reception control unit  15  performs control to transmit a signal transmission command to the NR system simulator  20  and transmit a test signal through the test antenna  6 , and performs control to transmit a signal reception command and receive a measurement target signal through the test antenna  6 . 
     The automatic antenna arrangement control unit  16  performs control to automatically arrange the plurality of test antennas  6 , which are held by the antenna holding mechanism  61  of the automatic antenna arrangement means  60 , at the focal position F of the reflector  7  in a sequential manner. In order to realize this control, for example, an automatic antenna arrangement control table  16   a  is stored in the ROM  11   b  in advance. For example, in a case where a stepping motor is adopted as the driving motor  65 , the automatic antenna arrangement control table  16   a  stores the number of driving pulses (the number of operation pulses) for determining the rotational driving of the stepping motor as control data. In the present embodiment, the automatic antenna arrangement control table  16   a  stores, as the control data, the number of operation pulses of the driving motor  65  for moving each test antenna  6  to the focal position F of the reflector  7  corresponding to, for example, each of the three measurement target frequency bands identified by the numbers 1 to 3 shown in  FIG. 8 . 
     The automatic antenna arrangement control unit  16  expands the automatic antenna arrangement control table  16   a  to the work area of the RAM  11   c , and performs control for rotationally driving the driving motor  65  in the power unit  64  of the automatic antenna arrangement means  60  according to the measurement target frequency band corresponding to each test antenna  6  based on the automatic antenna arrangement control table  16   a . By this control, it is possible to realize automatic antenna arrangement control to stop (arrange) each test antenna  6  at the focal position F of the reflector  7  in a sequential manner. In the present embodiment, an example has been mentioned in which the automatic antenna arrangement control unit  16  rotationally drives the driving motor  65  so that the test antenna  6  rotates in one direction (refer to  FIGS. 1 and 9 ). However, the present invention is not limited thereto, and the automatic antenna arrangement control unit  16  may rotationally drive the driving motor  65  so that the test antenna  6  rotates in the reverse direction or in both directions. This point is the same as in the second and third embodiments. 
     The DUT posture control unit  17  controls the posture of the DUT  100  held by the DUT holding unit  56  during measurement. In order to realize this control, for example, a DUT posture control table  17   a  is stored in the ROM  11   b  in advance. The DUT posture control table  17   a  stores, for example, control data of the two-axis positioner  56   a  that forms the DUT holding unit  56 . 
     The DUT posture control unit  17  expands the DUT posture control table  17   a  to the work area of the RAM  11   c , and controls the driving of the two-axis positioner  56   a , based on the DUT posture control table  17   a , to change the posture of the DUT  100  so that the antenna  110  is sequentially directed to all points on the surface of the sphere. 
     In the measurement apparatus  1  according to the present embodiment, example, as shown in  FIG. 4 , the NR system simulator  20  has a signal measurement unit  21 , a control unit  22 , an operation unit  23 , and a display unit  24 . The signal measurement unit  21  has a signal generation function unit, which is formed by a signal generation unit  21   a , a digital to analog converter (DAC)  21   b , a modulation unit  21   c , and a transmission unit  21   e  of an RF unit  21   d , and a signal analysis function unit, which is formed by a reception unit  21   f  of the RF unit  21   d , an analog/digital converter (ADC)  21   g , and an analysis processing unit  21   h.    
     In the signal generation function unit of the signal measurement unit  21 , the signal generation unit  21   a  generates waveform data having a reference waveform, specifically, an I component baseband signal and a Q component baseband signal that is a quadrature component signal of the I component baseband signal, for example. The DAC  21   b  converts the waveform data (the I component baseband signal and the Q component baseband signal) having a reference waveform output from the signal generation unit  21   a  from a digital signal to an analog signal, and outputs the analog signal to the modulation unit  21   c . The modulation unit  21   c  mixes each of the I component baseband signal and the Q component baseband signal with a local signal, and performs modulation processing for combining both the signals and outputting the result as a frequency of digital modulation. The RF unit  21   d  generates a test signal in which the frequency of digital modulation output from the modulation unit  21   c  corresponds to the frequency of each communication standard, and the generated test signal is output to the DUT  100  by the transmission unit  21   e.    
     In the signal analysis function unit of the signal measurement unit  21 , the RF unit  21   d  receives a measurement target signal, which is transmitted from the DUT  100  that has received the above-described test signal through the antenna  110 , using the reception unit  21   f  and then mixes the measurement target signal with a local signal to perform conversion into an intermediate frequency band (IF signal). The ADC  21   g  converts the measurement target signal, which has been converted into the IF signal by the reception unit  21   f  of the RF unit  21   d , from an analog signal to a digital signal, and outputs the digital signal to the analysis processing unit  21   h.    
     The analysis processing unit  21   h  generates waveform data corresponding to the I component baseband signal and the Q component baseband signal by performing digital processing on the measurement target signal output from the ADC  21   g , and then performs processing for analyzing the I component baseband signal and the Q component baseband signal based on the waveform data. 
     Similarly to the control unit  11  of the integrated control device  10  described above, the control unit  22  is, for example, a computer apparatus including a CPU, a RAM, a ROM, and various input and output interfaces. The CPU performs predetermined information processing and control for realizing each function of the signal generation function unit, the signal analysis function unit, the operation unit  23 , and the display unit  24 . 
     The operation unit  23  and the display unit  24  are connected to the input and output interfaces of the computer apparatus described above. The operation unit  23  is a functional unit that inputs various kinds of information, such as commands, and the display unit  24  is a functional unit that displays various kinds of information, such as an input screen for the various kinds of information and measurement results. 
     Next, processing for measuring the transmission and reception characteristics of the DUT  100  using the measurement apparatus  1  according to the present embodiment will be described with reference to  FIG. 10 . In  FIG. 10 , in particular, it is assumed that the three test antennas  6  capable of using the respective frequency bands indicated by the numbers 1, 2, and 3 in the 5G NR band (refer to  FIG. 8 ) are sequentially arranged at the focal position F to measure the DUT  100 . In the following description, it is assumed that the frequency band indicated by the number 1 is referred to as an in-band, the frequency band indicated by the number 2 is referred to as out-band  1 , and the frequency band indicated by the number 3 is referred to as out-band  2 . 
     In addition, in  FIG. 10 , a case will be described in which a measurement start operation for giving an instruction to start the process of measuring the transmission and reception characteristics of the DUT  100  is performed by the operation unit  12  of the integrated control device  10 . The measurement start operation may also be performed by the operation unit  23  of the NR system simulator  20 . 
     In the measurement apparatus  1 , in order to measure the transmission and reception characteristics of the DUT  100 , the DUT  100  needs to be set in the internal space  51  of the OTA chamber  50  first. Therefore, in the measurement apparatus  1 , a work for setting the DUT  100  to be tested on the DUT mounting unit  56   c  of the DUT holding unit  56  of the OTA chamber  50  is performed as the first processing by the user (step S 1 ). In this case, for the automatic antenna arrangement means  60 , a plurality of test antennas  3  (in this example, three test antennas  6 ), by which three measurement target frequency band can be covered, need to be held by the antenna holding mechanism  61 , and the antenna holding mechanism  61  needs to be provided at a position where each test antenna  6  can pass through the focal position F (refer to  FIG. 7 ) of the reflector  7  in a sequential manner. 
     After the work for setting the DUT  100  is performed, for example, the automatic antenna arrangement control unit  16  in the integrated control device  10  monitors whether or not an operation to start the measurement of the transmission and reception characteristics of the DUT  100  has been performed through the operation unit  12  (step S 2 ). 
     Here, in a case where it is determined that the measurement start operation has not been performed (NO in step S 2 ), the automatic antenna arrangement control unit  16  continues monitoring in step S 1  described above. On the other hand, in a case where it is determined that the measurement start operation has been performed (YES in step S 2 ), the automatic antenna arrangement control unit  16  sets n indicating the measurement order of the measurement target frequency band to n=1 indicating the first measurement target frequency band (step S 3 ). In this example, the maximum value of n is 3. 
     Then, the automatic antenna arrangement control unit  16  performs control to automatically move (arrange) the test antenna  6 , which corresponds to the first measurement target frequency band corresponding to n=1, to the focal position F of the reflector  7  (step S 4 ). In this case, the automatic antenna arrangement control unit  16  reads the number of operation pulses of the test antenna  6  corresponding to the first measurement target frequency band (in-band) corresponding to n=1 from the automatic antenna arrangement control table  16   a , and controls the rotation of the driving motor  65  based on the number of operation pulses. 
     After the end of the automatic arrangement of the reflector  7  of the test antenna  6  corresponding to the first measurement target frequency band to the focal position F by the rotation control described above, the call connection control unit  14  of the control unit  11  performs call connection control by transmitting and receiving a control signal (radio signal) to and from the DUT  100  using the test antenna  6  whose automatic arrangement has been completed (step S 5 ). Here, the NR system simulator  20  performs call connection control to wirelessly transmit a control signal (call connection request signal) having a frequency in a first transmission and reception measurement target frequency band to the DUT  100  through the test antenna  6  and receive a control signal (call connection response signal) transmitted after setting the connection requested frequency by the DUT  100  having received the call connection request signal. By the call connection control, a state in which a radio signal in the first transmission and reception measurement target frequency band can be transmitted and received through the test antenna  6  automatically arranged at the focal position F of the reflector  7  and the reflector  7  is established between the NR system simulator  20  and the DUT  100 . 
     In the DUT  100  after the completion of call connection control, processing for receiving the radio signal transmitted from the NR system simulator  20  through the test antenna  6  and the reflector  7  is downlink (DL) processing, and conversely, processing for transmitting the radio signal to the NR system simulator  20  through the reflector  7  and the test antenna  6  is uplink (UL) processing. The test antenna  6  is used to perform processing for establishing a link (call) and processing of downlink (DL) and uplink (UL) after link establishment, and may be referred to as a link antenna. 
     After establishing the call connection in step S 5 , the signal transmission and reception control unit  15  of the integrated control device  10  transmits a signal transmission command to the NR system simulator  20 . Based on the signal transmission command, the NR system simulator  20  performs control to transmit a test signal to the DUT  100  through the test antenna  6  automatically arranged at the focal position F of the reflector  7  (step S 6 ). 
     The test signal transmission control of the NR system simulator  20  is performed as follows. In the NR system simulator  20  (refer to  FIG. 4 ), the control unit  22  that has received the above-described signal transmission command controls the signal generation function unit to generate a signal for generating a test signal in the signal generation unit  21   a . Thereafter, this signal is subjected to digital/analog conversion processing by the DAC  21   b  and subjected to modulation processing by the modulation unit  21   c . Then, the RF unit  21   d  generates a test signal in which the digitally modulated frequency corresponds to the frequency of each communication standard, and the transmission unit  21   e  outputs the test signal (DL data) to the DUT  100  through the test antenna  6 . After starting the control of the test signal transmission in step S 5 , the signal transmission and reception control unit  15  performs control to transmit a test signal at an appropriate timing until the measurement of the transmission and reception characteristics of the DUT  100  in a frequency band corresponding to the test antenna  6  ends. In addition, during this period of time, in the integrated control device  10 , the DUT posture control unit  17  continues to control the two-axis positioner  56   a  so that the DUT  100  mounted on the DUT mounting unit  56   c  has the above-described posture. 
     On the other hand, the DUT  100  operates such that the test signal (DL data) transmitted through the test antenna  6  and the reflector  7  is received by the antenna  110  in the state of sequentially different postures based on the above-described posture control and the measurement target signal, which is a response signal with respect to the test signal, is transmitted. 
     After the transmission of the test signal is started in step S 6 , the signal transmission and reception control unit  15  performs processing causing the test antenna  6 , which is automatically arranged at the focal position F of the reflector  7 , to receive the measurement target signal that is transmitted from the DUT  100  having received the test signal and reflected by the reflector  7  (step S 7 ). 
     At the time of the reception processing, the measurement target signal received through the test antenna  6  is input to the signal processing unit  40 . The signal processing unit  40  is formed by an up converter, a down converter, an amplifier, a frequency filter, and the like. The signal processing unit  40  performs each processing of frequency conversion (up conversion or down conversion), amplification, and frequency selection on the measurement target signal input from the test antenna  6 . 
     Then, the NR system simulator  20  performs processing for measuring the measurement target signal frequency-converted by the frequency converter (step S 8 ). In this measurement processing, the frequency-converted measurement target signal is input to the reception unit  21   f  of the RF unit  21   d  in the NR system simulator  20  (refer to  FIG. 4 ). 
     In the NR system simulator  20 , the control unit  22  controls the signal analysis function unit to convert the measurement target signal input to the reception unit  21   f  of the RF unit  21   d  into an IF signal first. Then, the control unit  22  performs control such that the analog signal is converted into a digital signal by the ADC  21   g  and input to the analysis processing unit  21   h  and waveform data corresponding to the I component baseband signal and the Q component baseband signal is generated by the analysis processing unit  21   h . In addition, the control unit  22  controls the analysis processing unit  21   h  to analyze the measurement target signal based on the generated above-described waveform data. 
     In the NR system simulator  20 , the control unit  22  performs control to measure the transmission and reception characteristics of the DUT  100  based on the analysis result of the measurement target signal by analysis processing unit  21   h  (step S 8 ). For example, for the transmission characteristics of the DUT  100 , the control unit  22  performs processing for transmitting a Ping request frame as a test signal from the NR system simulator  20  and evaluating the transmission characteristics of the DUT  100  based on a Ping Reply frame transmitted as a measurement target signal from the DUT  100  in response to the Ping request frame. In addition, for the reception characteristics of the DUT  100 , the control unit  22  calculates, as an error rate (BER), a ratio between the number of transmissions of the measurement frame transmitted as a test signal from the NR system simulator  20  and the number of receptions of ACK transmitted as a measurement target signal from the DUT  100  in response to the measurement frame. In accordance with the control to measure the transmission and reception characteristics of the DUT  100  in step S 8 , in the integrated control device  10 , for example, the control unit  32  performs control to store the analysis result of the measurement target signal by the NR system simulator  20  in a storage region, such as a RAM (not shown), as transmission and reception characteristics. 
     Then, in the integrated control device  10 , for example, the automatic antenna arrangement control unit  16  determines whether or not the measurement of the transmission and reception characteristics of the DUT  100  has ended for the first measurement target frequency band corresponding to n=1 (step S 9 ). Here, in a case where it is determined that the measurement for the first measurement target frequency band has not ended (NO in step S 9 ), processing from step S 6  is continued. 
     On the other hand, in a case where it is determined that the measurement for the first measurement target frequency band has ended (YES in step S 9 ), the automatic antenna arrangement control unit  16  determines whether or not n has reached n=3 indicating the last measurement target frequency band (out-band  2 ) (step S 10 ). Here, in a case where it is determined that n has not reached n=3 (NO in step S 10 ), the automatic antenna arrangement control unit  16  proceeds to step S 3  to set n to n=2 indicating the second frequency band (out-band  1 ) (step S 3 ). 
     Then, using the same method as in the case of n=1, the automatic antenna arrangement control unit  16  performs control to automatically move the test antenna  6 , which corresponds to the second measurement target frequency band corresponding to n=2, to the focal position F of the reflector  7  (step S 4 ). Then, the call connection control unit  14  performs call connection control to establish a call between the NR system simulator  20  and the DUT  100  by driving the test antenna  6  newly arranged at the focal position F of the reflector  7  to (step S 5 ). 
     Thereafter, the integrated control device  10  performs the processing of S 6  to S 10  (the same as the processing performed according to transmission and reception of the test signal and the measurement target signal by the test antenna  6  corresponding to the first measurement target frequency band) according to transmission and reception of the test signal and the measurement target signal by the test antenna  6  corresponding to the second measurement target frequency band corresponding to n=2. 
     During this period of time, in the integrated control device  10 , the automatic antenna arrangement control unit  16  determines whether or not the measurement of the transmission and reception characteristics of the DUT  100  for the second measurement target frequency band has ended (step S 9 ). Here, in a case where it is determined that the measurement has not ended (NO in step S 9 ), processing from step S 6  is continued. 
     On the other hand, in a case where it is determined that the measurement of the transmission and reception characteristics of the DUT  100  for the second measurement target frequency band has ended (YES in step S 9 ), the automatic antenna arrangement control unit  16  determines whether or not n has reached n=3 (step S 10 ). In a case where it is determined that n has not reached n=3 (NO in step S 10 ), the automatic antenna arrangement control unit  16  proceeds to step S 3  to set n to n=3 indicating the third frequency band (out-band  2 ) (step S 3 ). 
     Then, using the same method as in the case of n=1 and 2, the automatic antenna arrangement control unit  16  performs control to automatically move the test antenna  6 , which corresponds to the third measurement target frequency band corresponding to n=3, to the focal position F of the reflector  7  (step S 4 ). Then, the call connection control unit  14  performs call connection control to establish a call between the NR system simulator  20  and the DUT  100  by driving the test antenna  6  newly arranged at the focal position F of the reflector  7  (step S 5 ). 
     Thereafter, the integrated control device  10  performs the processing of S 6  to S 10  (the same as the processing performed according to transmission and reception of the test signal and the measurement target signal by the test antenna  6  corresponding to the first and second measurement target frequency bands) according to transmission and reception of the test signal and the measurement target signal by the test antenna  6  corresponding to the third measurement target frequency band corresponding to n=3. 
     During this period of time, in the integrated control device  10 , the automatic antenna arrangement control unit  16  determines whether or not the measurement of the transmission and reception characteristics of the DUT  100  for the third measurement target frequency band has ended (step S 9 ). Here, in a case where it is determined that the measurement has not ended (NO in step S 9 ), processing from step S 6  is continued. 
     On the other hand, in a case where it is determined that the measurement of the transmission and reception characteristics of the DUT  100  for the third measurement target frequency band has ended (YES in step S 9 ), the integrated control device  10  determines whether or not n has reached n=3 (YES in step S 10 ), and the series of measurement processing described above are ended. 
     As described above, the measurement apparatus (antenna apparatus)  1  according to the present embodiment includes: the OTA chamber  50  having the internal space  51  that is not influenced by the surrounding radio wave environment; the reflector  7  that is housed in the internal space  51  and has a predetermined paraboloid of revolution, radio signals transmitted or received by the antenna  110  of the DUT  100  being reflected through the paraboloid of revolution; a plurality of test antennas  6  that use radio signals in a plurality of measurement target frequency bands for measuring transmission and reception characteristics of the DUT  100 ; and the automatic antenna arrangement means  60  for sequentially arranging the plurality of test antennas  6  at the focal position F, which is determined from the paraboloid of revolution, according to the measurement target frequency bands. 
     With this configuration, in the measurement apparatus  1  according to the present embodiment, the user does not need to perform a work for sequential replacement of the plurality of test antennas  6  at the focal position F of the reflector  7  during the measurement of the transmission and reception characteristics of the DUT  100  using the OTA chamber  50 . In addition, since the automatic antenna arrangement means  60  is added after shortening the signal propagation path by providing the reflector  7 , this is not a major obstacle for the OTA chamber  50  to be made compact. In addition, since it is possible to measure the transmission and reception characteristics of the DUT  100  for each measurement target frequency band without interruption while reducing the time and effort for arranging each test antenna  6 , the efficiency of the measurement processing can be improved. 
     In the measurement apparatus  1  according to the present embodiment, the antenna  110  of the DUT  100  uses a radio signal in a specified frequency band. Each time one of the plurality of test antennas  6  is arranged at the focal position F of the reflector  7 , a test signal is output to the DUT  100  through the test antenna  6  arranged at the focal position F, and a measurement target signal output from the DUT  100  to which the test signal has been input is received by the test antenna  6  arranged at the focal position F. The NR system simulator  20  that measures the transmission and reception characteristics of the DUT  100  for a radio signal in the measurement target frequency band, which is used by the test antenna  6  arranged at the focal position F, based on the received measurement target signal is further provided. 
     With this configuration, the measurement apparatus  1  according to the present embodiment can smoothly measure the transmission and reception characteristics of the DUT  100 , which has the antenna  110  using a radio signal in a specified frequency band, without much time and effort for replacement of the test antenna  6  for frequency bands of a plurality of different frequency band groups in the specified frequency band. 
     In the measurement apparatus  1  according to the present embodiment, the specified frequency band is a 5G NR band, and each of the plurality of measurement target frequency bands is a frequency band of any one of frequency band groups of a group of n77, n78, and n79, a group of n258 and n257, and a group of n259 that are a plurality of different frequency band groups in the 5G NR band. 
     With this configuration, the measurement apparatus  1  according to the present embodiment can smoothly measure the transmission and reception characteristics of the DUT (5G wireless terminal), which has the antenna  110  using a radio signal in the 5G NR band, without much time and effort for replacement of the test antenna  6  for a frequency band of any one of frequency band groups of a group of n77, n78, and n79, a group of n258 and n257, and a group of n259. 
     In the measurement apparatus  1  according to the present embodiment, the automatic antenna arrangement means  60  is configured to include: the antenna holding mechanism  61  in which each test antenna  6  is arranged on the circumference around the rotary shaft  63  in the rotating body  62  that can rotate around the rotary shaft  63  and which is provided in the internal space  51  of the OTA chamber  50  so that the receiving surface of each test antenna  6  passes through the focal position F of the reflector  7  by rotation of the rotating body  62 ; the power unit  64  having the driving motor  65  for rotationally driving the rotating body  62  through the rotary shaft  63 ; and the automatic antenna arrangement control unit  16  that controls the driving motor  65  so that each test antenna  6  is sequentially stopped at the focal position F according to the measurement target frequency band. 
     With this configuration, since the measurement apparatus  1  according to the present embodiment adopts the antenna holding mechanism  61  in which each test antenna  6  is arranged on the circumference around the rotary shaft  63 , it is possible to reduce the installation space of the antenna holding mechanism  61  while keeping the OTA chamber  50  compact. 
     In the measurement apparatus  1  according to the present embodiment, the antenna holding mechanism  61  is provided on the bottom surface  52   a  of the internal space  51  of the OTA chamber  50 , and is formed by the rotating body  62  that can rotate along a plane in the horizontal direction by the rotary shaft  63  along the vertical direction. With this configuration, in the measurement apparatus  1  according to the present embodiment, a space horizontal to the bottom surface  52   a  of the internal space  51  of the OTA chamber  50  is secured as an installation space of the antenna holding mechanism  61 . Therefore, it is possible to prevent an increase in the height of the OTA chamber  50 . 
     In the measurement apparatus  1  according to the present embodiment, the antenna holding mechanism  61  holds each test antenna  6  so that the receiving surface of the test antenna  6  is directed to the rotary shaft  63  side. With this configuration, in the measurement apparatus  1  according to the present embodiment, the antenna holding mechanism  61  is arranged at the central portion of the bottom surface  52   a  of the internal space  51  of the OTA chamber  50 . Therefore, since the diameter of the circumference on which each test antenna  6  is arranged can be reduced, it is possible to keep the antenna holding mechanism  61  and the OTA chamber  50  compact. 
     In the measurement apparatus  1  according to the present embodiment, in a case where the test antenna  6  is stopped at the focal position F of the reflector  7 , the antenna holding mechanism  61  holds the test antenna  6  so as to face the reflector  7  at an angle at which the receiving surface of the test antenna  6  is perpendicular to the beam axis of the radio signal, for example, at an elevation angle of 30°. With this configuration, in the measurement apparatus  1  according to the present embodiment, it is possible to improve the reception accuracy of the test antenna  6  arranged at the focal position F of the reflector  7  and improve the measurement accuracy of the transmission and reception characteristics of the DUT  100 . 
     The measurement method according to the present embodiment is a measurement method using the measurement apparatus  1  having the configuration described above, and includes: a holding step of holding the DUT  100  in the DUT holding unit  56  in the OTA chamber  50  (step S 1  in  FIG. 10 ); an antenna arrangement step of sequentially arranging a plurality of test antennas  6  at the focal position F according to the measurement target frequency band based on a predetermined measurement start command (steps S 3  and S 4  in  FIG. 10 ); a test signal output step of causing the NR system simulator  20  to output a test signal to the DUT  100  through the test antenna  6  arranged at the focal position F (step S 6  in  FIG. 10 ); a signal receiving step of receiving a measurement target signal, which is output from the DUT  100  to which the test signal has been input, through the test antenna  6  arranged at the focal position F (step S 7  in  FIG. 10 ); and a measurement step of measuring transmission and reception characteristics of the DUT  100  for a radio signal in the measurement target frequency band, which is used by the test antenna  6  arranged at the focal position F, based on the measurement target signal received in the signal receiving step (step S 8  in  FIG. 10 ). 
     With this configuration, in the measurement method according to the present embodiment, since the measurement apparatus (antenna apparatus)  1  having the OTA chamber  50  in which the automatic antenna arrangement means  60  is provided is used, the user does not need to perform a work for sequential replacement of the plurality of test antennas  6  at the focal position F of the reflector  7  during the measurement of the transmission and reception characteristics of the DUT  100 . In addition, since the automatic antenna arrangement means  60  is added after shortening the signal propagation path by providing the reflector  7 , this is not a major obstacle for the anechoic box to be made compact. In addition, since it is possible to measure the transmission and reception characteristics of the DUT  100  for each measurement target frequency band without interruption while reducing the time and effort for arranging each test antenna  6  at the focal position F, the efficiency of the measurement processing can be improved. 
     Second Embodiment 
     As shown in  FIG. 11 , in a measurement apparatus  1 A according to a second embodiment of the present invention, an OTA chamber  50 A adopting automatic antenna arrangement means  60 A is used instead of the OTA chamber  50  used in the measurement apparatus  1  according to the first embodiment. In the automatic antenna arrangement means  60 A, the same components as the automatic antenna arrangement means  60  (refer to  FIGS. 1 and 2 ) mounted in the OTA chamber  50  according to the first embodiment are denoted by the same reference numerals. 
     As shown in  FIG. 11 , similarly to the automatic antenna arrangement means  60  according to the first embodiment, the automatic antenna arrangement means  60 A according to the present embodiment has: an antenna holding mechanism  61  in which each test antenna  6  is arranged on the circumference around a rotary shaft  63  in a rotating body  62  that can rotate around the rotary shaft  63  and which is provided in the internal space of the OTA chamber  50 A so that the receiving surface of each test antenna  6  passes through the focal position F of a reflector  7  by rotation of the rotating body  62 ; and a power unit  64  having a driving motor  65  for rotationally driving the rotating body  62  through the rotary shaft  63 . That is, also in the automatic antenna arrangement means  60 A according to the present embodiment, the antenna holding mechanism  61  is provided on the bottom surface of the internal space  51  of the OTA chamber  50 A, and is formed by the rotating body  62  that can rotate along a plane in the horizontal direction by the rotary shaft  63  along the vertical direction. 
     The automatic antenna arrangement means  60 A according to the present embodiment has the same configuration as the automatic antenna arrangement means  60  according to the first embodiment except for the arrangement of the test antenna  6  with respect to the rotating body  62 . In the automatic antenna arrangement means  60  according to the first embodiment, the antenna holding mechanism  61  holds each test antenna  6  so that the receiving surface of each test antenna  6  is directed to the rotary shaft  63  side (inner side) (refer to  FIG. 1 ). In contrast, in the automatic antenna arrangement means  60 A according to the present embodiment, as shown in  FIG. 11 , the antenna holding mechanism  61  holds each test antenna  6  so that the receiving surface of each test antenna  6  is directed to the opposite side (outer side) to the rotary shaft  63  side. 
     Also in the automatic antenna arrangement means  60 A according to the present embodiment, the driving motor  65  forming the power unit  64  is connected to the automatic antenna arrangement control unit  16 . In addition, also in the present embodiment, the automatic antenna arrangement control table  16   a  is prepared in advance in which the number of operation pulses (here, a value different from that in the first embodiment) that can be arranged at the focal position F of the reflector  7  corresponding to each test antenna  6  is stored. Therefore, also in the measurement apparatus  1 A according to the present embodiment, as in the first embodiment, the automatic antenna arrangement control unit  16  reads the number of operation pulses of each test antenna  6  from the automatic antenna arrangement control table  16   a  and controls the rotation of the driving motor  65  based on the number of pulses, along the flowchart shown in  FIG. 10 , so that each test antenna  6  can be sequentially arranged at the focal position F of the reflector  7  (refer to step S 4  in  FIG. 10 ). 
     In the measurement apparatus (antenna apparatus)  1 A according to the present embodiment, the automatic antenna arrangement means  60 A for automatically arranging the test antenna  6  at the focal position F of the reflector  7  in a sequential manner. Therefore, as in the first embodiment, it is possible to easily measure the transmission and reception characteristics of the DUT  100  without forcing the user to perform a work for replacement of the plurality of test antennas  6 . In particular, according to the configuration of the OTA chamber  50 A having the automatic antenna arrangement means  60 A according to the present embodiment, for example, the antenna holding mechanism  61 A is arranged at a position avoiding the central portion of the bottom surface  52   a  of the internal space  51 . Therefore, the diameter of the circumference on which the test antenna  6  is arranged is reduced. This is useful for making the antenna holding mechanism  61 A small. 
     Third Embodiment 
     As shown in  FIGS. 12A and 12B , in a measurement apparatus  1 B according to a third embodiment of the present invention, an OTA chamber  50 B adopting automatic antenna arrangement means  60 B is used instead of the OTA chambers  50  and  50 A used in the measurement apparatuses  1  and  1 A according to the first and second embodiments.  FIG. 12A  shows a schematic configuration viewed from the front of the automatic antenna arrangement means  60 B, and  FIG. 12B  shows a schematic configuration of the automatic antenna arrangement means  60 B viewed from the right side of  FIG. 12A . 
     The automatic antenna arrangement means  60  and  60 A of the measurement apparatuses  1  and  1 A according to the first and second embodiments has the antenna holding mechanism  61  that holds a plurality of test antennas  6  on the circumference of the rotating body  62  that can rotate on the horizontal plane through the rotary shaft  63  perpendicular to the horizontal plane. In contrast, as shown in  FIGS. 12A and 12B , the automatic antenna arrangement means  60 B according to the present embodiment has an antenna holding mechanism  61 B that holds a plurality of test antennas  6  on the circumference along the outer periphery of a rotating body  62 B that can rotate along a plane in the vertical direction through a rotary shaft  63 B extending in the horizontal direction. A power unit  64 B of the automatic antenna arrangement means  60 B is formed by the same driving motor  65 B as the driving motor  65  according to the first and second embodiments and a connection member  66 B interposed between the driving motor  65 B and the rotary shaft  63 B of the rotating body  62 B. 
     The automatic antenna arrangement means  60 B according to the present embodiment is different from the first and second embodiments in that the plurality of test antennas  6  held by the antenna holding mechanism  61 B rotate along the plane in the vertical direction with rotation of the rotating body  62 B. However, the automatic antenna arrangement means  60 B according to the present embodiment is the same as the first and second embodiments in that the movement of each test antenna  6  to a predetermined position on the circumference, in particular, the focal position F of the reflector  7  can be controlled by the amount of rotation of the driving motor  65 B, that is, the number of driving pulses applied to the driving motor  65 B. 
     Therefore, also in the present embodiment, the automatic antenna arrangement control table  16   a  is prepared in advance in which the number of operation pulses (here, a value different from those in the first and second embodiments) that can be arranged at the focal position F of the reflector  7  corresponding to each test antenna  6  is stored. Then, in the automatic antenna arrangement control unit  16  to which the driving motor  65 B forming the power unit  64 B of the automatic antenna arrangement means  60 B is connected, driving control of the driving motor  65 B is performed based on the automatic antenna arrangement control table  16   a . In this case, the automatic antenna arrangement control unit  16  reads the number of operation pulses of each test antenna  6  from the automatic antenna arrangement control table  16   a  and controls the rotation of the driving motor  65 B based on the number of pulses, so that each test antenna  6  can be sequentially arranged at the focal position F of the reflector  7  (refer to step S 4  in  FIG. 10 ). 
     In the measurement apparatus (antenna apparatus)  1 B according to the present embodiment, the automatic antenna arrangement means  60 B for automatically arranging the test antenna  6  at the focal position F of the reflector  7  in a sequential manner. Therefore, as in the first embodiment, it is possible to easily measure the transmission and reception characteristics of the DUT  100  without forcing the user to perform a work for replacement of the plurality of test antennas  6 . In particular, according to the configuration of the OTA chamber  50 B having the automatic antenna arrangement means  60 B according to the present embodiment, a space perpendicular to the bottom surface  52   a  of the internal space  51  can be secured as an installation space of the antenna holding mechanism  61 B. Therefore, it is possible to prevent an increase in the width of the housing main body  52 . 
     Fourth Embodiment 
     As shown in  FIG. 13 , in a measurement apparatus  1 C according to a fourth embodiment of the present invention, an OTA chamber  50 C adopting automatic antenna arrangement means  80  is used instead of the OTA chamber  50  used in the measurement apparatus  1  according to the first embodiment. In the present embodiment, an example has been mentioned in which the automatic antenna arrangement means  80  automatically arranges the nine test antennas  6  that can use different measurement target frequency bands. However, it is needless to say that the present invention can also be applied to a case where the three test antennas  6  exemplified in the first to third embodiments as will be described below. 
     As shown in  FIG. 13 , the automatic antenna arrangement means  80  according to the present embodiment has an antenna holding mechanism  81  and a power unit  87 . The antenna holding mechanism  81  is formed by a plurality of first slide mechanisms  81   a ,  81   b , and  81   c  and a second slide mechanism  84  arranged perpendicular to the first slide mechanisms  81   a ,  81   b , and  81   c . Each of the first slide mechanisms  81   a ,  81   b , and  81   c  has a plurality of antenna pedestals  82 , and is configured to hold the antenna pedestals  82  so as to be slidable in one direction while maintaining a predetermined interval along a pair of guide rails  83 , for example. Here, the one direction is, for example, a Y axis direction on a plane formed by an X axis and a Y axis perpendicular to each other. The test antenna  6  is attached to each of the antenna pedestals  82 . 
     In  FIG. 13 , the configuration in which the nine test antennas  6  attached to the nine antenna pedestals  82  are automatically arranged at the focal position F is illustrated. However, the automatic antenna arrangement means  80  can respond to the automatic arrangement of any number of test antennas  6  by changing or modifying the configuration. For example, in order for the automatic antenna arrangement means  80  to automatically arrange the three test antennas  6  as in the first to third embodiments, each test antenna  6  may be provided on three antenna pedestals  82  in  FIG. 13 . In addition, by configuring the automatic antenna arrangement means  80  shown in  FIG. 13  such that only one first slide mechanism (for example,  81   a ) is provided or only the second slide mechanism  84  is provided, it is possible to respond to the automatic arrangement of the three test antennas  6 . 
     On the other hand, the second slide mechanism  84  has a pedestal portion  85  on which the first slide mechanisms  81   a ,  81   b , and  81   c  are mounted, and holds the first slide mechanisms  81   a ,  81   b , and  81   c  so as to be slidable in the other direction perpendicular to the Y axis direction along a pair of guide rails  86 , for example. 
     The power unit  87  has driving shafts  87   a ,  87   b , and  87   c , which are provided along the Y axis direction so as to pass through a through hole  82   a  of the antenna pedestal  82  forming each of the first slide mechanisms  81   a ,  81   b , and  81   c , and first driving motors  88   a ,  88   b , and  88   c  for rotationally driving the driving shafts  87   a ,  87   b , and  87   c . In addition, the power unit  87  has a driving shaft  89   a , which is provided along the X axis direction so as to pass through a through hole  85   a  of the pedestal portion  85  forming the second slide mechanism  84 , and a second driving motor  89   b  for rotationally driving the driving shafts  89   a . In the through hole  82   a  of each antenna pedestal  82  described above and the through hole  85   a  of each pedestal portion  85 , screws fitted to screws formed on the driving shafts  87   a ,  87   b , and  87   c  and the driving shaft  89   a  are formed. Therefore, the power unit  87  can move each antenna pedestal  82  in both directions corresponding to the forward and reverse rotation directions along the Y axis by rotationally driving the first driving motors  88   a ,  88   b , and  88   c  in both forward and reverse directions to rotationally drive the driving shafts  87   a ,  87   b , and  87   c  in the same direction. Similarly, it is possible to move each pedestal portion  85  in both directions corresponding to the forward and reverse rotation directions along the X axis by rotationally driving the second driving motor  89   b  in both forward and reverse directions to rotationally drive the driving shaft  89   a  in the same direction. 
     In the automatic antenna arrangement means  80  shown in  FIG. 13 , the antenna holding mechanism  81  is provided on, for example, the bottom surface  52   a  in the internal space  51  of the OTA chamber  50 C so that each test antenna  6  mounted on each antenna pedestal  82  can pass through the focal position F of the reflector  7 . In the configuration shown in  FIG. 13 , the focal position F of the reflector  7  can be expressed by the coordinates on the XY plane. The amount of movement of the pedestal portion  85  in the X axis direction corresponds to the number of operation pulses of the second driving motor  89   b , and the amount of movement of the antenna pedestal  82  in the Y axis direction corresponds to the number of operation pulses of the first driving motors  88   a ,  88   b , and  88   c.    
     Based on such conditions, in the measurement apparatus  1 C according to the present embodiment, as the automatic antenna arrangement control table  16   a , the number of operation pulses of the second driving motor  89   b  and the number of operation pulses of the first driving motors  88   a ,  88   b , and  88   c  that can be arranged at the focal position F of the reflector  7  corresponding to each test antenna  6  are stored as control data. Therefore, in the automatic antenna arrangement control unit  16 , it is possible to control the driving of the first driving motors  88   a ,  88   b , and  88   c  and the second driving motor  89   b  based on the automatic antenna arrangement control table  16   a . In this driving control, the automatic antenna arrangement control unit  16  reads the number of operation pulses of the second driving motor  89   b  and the number of operation pulses of the first driving motors  88   a ,  88   b , and  88   c  corresponding to each test antenna  6  from the automatic antenna arrangement control table  16   a  and controls the rotation of the first driving motors  88   a ,  88   b , and  88   c  and the second driving motor  89   b  based on the number of pulses, so that each test antenna  6  can be sequentially arranged at the focal position F of the reflector  7  (refer to step S 4  in  FIG. 10 ). 
     In the measurement apparatus (antenna apparatus)  1 C according to the present embodiment, the automatic antenna arrangement means  80  for automatically arranging the test antenna  6  at the focal position F of the reflector  7  in a sequential manner is provided on the XY plane. Therefore, as in the first to third embodiments, it is possible to easily measure the transmission and reception characteristics of the DUT  100  without forcing the user to perform a work for replacement of the plurality of test antennas  6 . In particular, according to the configuration of the OTA chamber  50 C having the automatic antenna arrangement means  80  according to the present embodiment, a space horizontal to the bottom surface  52   a  of the internal space  51  of the OTA chamber  50 C is secured as an installation space of the antenna holding mechanism  81 . Therefore, it is possible to prevent structural expansion of the OTA chamber  50 C (housing main body  52 ) in the height direction. In addition, since the test antennas  6  slide in directions perpendicular to each other on the horizontal plane, stable movement of the reflector  7  toward the focal position F is possible. 
     In the measurement apparatus  1 C according to the present embodiment, a plurality of first slide mechanisms  81   a ,  81   b , and  81   c  are provided so as to be parallel to the Y axis direction and be spaced apart from each other by a predetermined distance in the X axis direction, and the power unit  87  is configured to include the first driving motors  88   a ,  88   b , and  88   c  corresponding to the first slide mechanisms  81   a ,  81   b , and  81   c . With this configuration, the measurement apparatus  1  can easily cope with the addition of the test antenna  6  while avoiding an increase in the size of the OTA chamber  50 C by making full use of the space in the horizontal direction on the bottom surface  52   a  of the housing main body  52  of the OTA chamber  50 C. In the present embodiment, a plurality of first slide mechanisms and a plurality of first driving motors do not necessarily need to be provided, and one first slide mechanism and one first driving motor may be provided. 
     In each of the embodiments described above, an example has been mentioned in which the measurement of the transmission and reception characteristics of the DUT  100  in three bands (refer to  FIG. 8 ) in the 5G NR band are covered with, for example, three test antennas  6  (up to nine in the fourth embodiment). However, the present invention is not limited thereto, and the transmission and reception characteristics of the DUT  100  for a plurality of bands in the 5G NR band may be measured using any number of test antennas  6 . In addition, the means  60 ,  60 A,  60 B, and  60 C for automatically arranging the test antenna  6  is not limited to that described in each of the above embodiments, and it is needless to say that various modes including means for manually arranging the test antenna  6  can be applied. In addition, the present invention can be applied not only to the anechoic box but also to the anechoic chamber. 
     As described above, the antenna apparatus and the measurement method according to the present invention have an effect that the transmission and reception characteristics for frequency bands corresponding to a plurality of test antennas of the DUT can be efficiently measured while avoiding an increase in the size of the anechoic box and the complication of the work for replacement of the test antenna. This is useful for all kinds of antenna apparatuses and measurement methods for performing transmission and reception measurement of wireless terminals capable of using the 5G NR band. 
     DESCRIPTION OF REFERENCE NUMERALS AND SIGNS 
     
         
         
           
               1 ,  1 A,  1 B,  1 C: measurement apparatus (antenna apparatus) 
               6 : test antenna (antenna) 
               7 : reflector 
               10 : integrated control device 
               16 : automatic antenna arrangement control unit 
               20 : NR system simulator (simulation measurement device) 
               30 : signal analysis device 
               40 : signal processing unit 
               50 : OTA chamber (anechoic box) 
               51 : internal space 
               60 ,  60 A,  60 B: automatic antenna arrangement means (antenna arrangement means) 
               61 ,  61 B: antenna holding mechanism 
               62 ,  62 B: rotating body 
               63 ,  63 B: rotary shaft 
               64 ,  64 B: power unit 
               65 ,  65 B: driving motor 
               80 : automatic antenna arrangement means 
               81 : antenna holding mechanism 
               81   a ,  81   b ,  81   c : first slide mechanism 
               82 : antenna pedestal 
               84 : second slide mechanism 
               85 : pedestal portion 
               87 : power unit 
               87   a ,  87   b ,  87   c : first driving shaft 
               88   a ,  88   b ,  88   c : first driving motor 
               89   a : second driving shaft 
               89   b : second driving motor 
               100 : DUT (device under test) 
               110 : antenna (antenna to be tested) 
             F: focal position of reflector