Abstract:
The present invention relates to a portable directional antenna which is equipped with a camera which is integrated into the housing of the directional antenna. In addition to the conventional documentation of the position-finding information, this integrated, installed camera makes it possible, by means of the directional antenna function, to also optically document the surroundings of the interference source with a variable level of detail, for example by way long-range or short-range capture. By way of the optical additional information thus obtained, the present invention provides a simple, but nonetheless very effective, enhanced documentation option for interference sources and the surroundings thereof. Thus, during the search for radio-frequency interferences, no separate camera for capturing image information has to be brought along, and this increases the comfort for a user. The present invention further relates to a portable measurement arrangement and to a method for measuring an electromagnetic signal emitted by a source.

Description:
PRIORITY CLAIM 
       [0001]    This application claims the benefit of European Application No. 15165568.5, filed Apr. 29, 2015; the disclosure of which is incorporated herein by reference in its entirety. 
       FIELD OF THE INVENTION 
       [0002]    The present invention relates to a portable directional antenna. The present invention also relates to a portable measurement arrangement and to a method for measuring an electromagnetic signal emitted by a source. 
       TECHNICAL BACKGROUND 
       [0003]    The present invention relates to the detection of radio-frequency interferences. Radio-frequency interference (often also referred to as electromagnetic interference) refers to the effect of undesired energy resulting from emission, broadcasting or induction (or from a combination thereof), which can have a negative effect on the reception in a radio system. The present invention and the set of problems on which it is based are described in the following in relation to radio-frequency interferences in the field of mobile radio, but without limiting the invention thereto. 
         [0004]    Causes of radio-frequency interferences in the field of mobile radio may be defective antennae on a mobile radio mast. To locate an interference source of this type, directional antennae are used, for example. Directional antennae are receivers having a directional receiving characteristic which is amplified as a result of the design. As a receiving antenna, a directional antenna thus concentrates the maximum receiving sensitivity thereof in a desired direction, using an opening angle that is smaller or less small depending on the application. As a result of the directional effect, the reception of signals outside the primary lobe of the electromagnetic signal is attenuated. 
         [0005]    A directional antenna of this type is disclosed for example in DE 10 2010 051 213 A1. Using a directional antenna of this type, an interference source can be detected, and the exact GPS position can be determined by means of an installed GPS sensor. 
         [0006]    However, even with a directional antenna equipped with a GPS sensor, and thus even if the GPS position is known, it may not be possible to find the interference source retrospectively, for example if a plurality of interference sources are positioned close together, as may be the case in urban environments. Furthermore, radio-frequency interferences also occur inside buildings, where for example there is no GPS reception. 
       SUMMARY OF THE INVENTION 
       [0007]    Against this background, the object of the invention is to provide improved re-identification of a detected interference source. 
         [0008]    According to the invention, this object is achieved by a directional antenna having the features of claim  1  and/or by a measurement arrangement having the features of claim  10  and/or by a method having the features of claim  14 . 
         [0009]    Accordingly, the following is provided;
       A portable directional antenna, which is designed to detect position-finding data of an interference source emitting an electromagnetic interference signal, comprising an installed camera which is configured to capture image information from the surroundings of the directional antenna, in particular from the surroundings of the interference source.   A measurement arrangement comprising a directional antenna according to the invention, comprising a measurement device designed as a spectrum analyser, which is coupled to the directional antenna and which is designed to analyse an electromagnetic interference signal, received by the directional antenna, from an interference source.   A method for locating a radio-frequency interference source, comprising the following steps: determining the position of an interference source by detecting and evaluating an electromagnetic signal emitted by the interference source and by providing position-finding data from a direction of incidence of the detected electromagnetic signal; capturing image information from the surroundings of the interference source and/or from a location at which the electromagnetic signal was detected; storing the determined position and the associated image information.       
 
         [0013]    The idea behind the present invention is to equip a directional antenna known per se with a camera which is integrated into the housing of the directional antenna. In addition to the conventional documentation of the position-finding information, this integrated, installed camera makes it possible, by means of the directional antenna function, to also optically document the surroundings of the environment of the interference source with a variable level of detail, for example by way of long-range or short-range capture. By way of the optical additional information thus obtained, the present invention provides a simple, but nonetheless very effective, enhanced documentation option for interference sources and the surroundings thereof. Thus, during the search for radio-frequency interferences, no separate camera for capturing image information has to be brought along, and this increases the comfort for a user. 
         [0014]    Advantageous configurations and developments may be taken from the further, dependent claims and from the description with reference to the drawings. 
         [0015]    In a preferred embodiment, the camera is in the form of a digital camera. A digital camera conventionally comprises an integrated memory, which according to the invention is used to store detected position-finding data and image information. In particular, it is thus possible to store the position-finding data captured by the directional antenna and the image information captured by the camera thereof in an associated manner. As a result, the corresponding associated image information is automatically assigned to the detected position-finding data, which simplifies subsequent analysis. In addition, this reduces the amount of human labour, since said data no longer have to be specially identified and combined in subsequent data processing. In addition, as a result of this type of associated data store, it is possible to prevent errors due to subsequent incorrect combination of data, for example caused by the user no longer being able to tell which image data belong with which image information. Alternatively, it is also conceivable to configure the camera as an analogue camera, COD sensor or the like. 
         [0016]    In a further preferred embodiment, the directional antenna comprises a GPS sensor. This GPS sensor is designed to detect GPS position data of the location at which the position-finding data and/or the image information were captured. GPS data are particularly advantageous during a search for interference sources outside buildings and in a spacious environment, since in this way a more or less distinct position of the interference source is provided. It is particularly advantageous if the position-finding data and/or the image information are in effect provided with an electronic GPS position stamp. Alternatively, associated GPS position data, position-finding data and/or image information may also be stored separately from one another. 
         [0017]    In a further embodiment, the directional antenna additionally comprises a device for time detection so as to obtain time information associated with the position-finding data and/or image information. The time information may for example be stored as a timestamp based on the position-finding data or image information. This ensures that associated position-finding data and image information can be identified exactly, even in the case of large datasets. In addition, documenting a time, a date and/or a duration is significant and advantageous in particular in the case of interference signals which merely occur temporarily, intermittently etc. Furthermore, assigning position-finding data to time information also makes it possible to document any noise that interferes with the electromagnetic signal. 
         [0018]    In a further, particularly preferred embodiment, the directional antenna has a control device coupled to the camera. The control device is preferably designed to trigger the camera automatically in a manner depending on a predetermined condition. In particular, it is advantageous if the predetermined condition is at least in the form of a threshold for the electromagnetic signal. A threshold for the electromagnetic signal may for example be an amplitude, a signal intensity, a signal scattering, a particular predetermined noise and/or a frequency of the electromagnetic interference signal. For example, it may be provided that the camera triggers automatically if the directional antenna qualifies a detected signal as an interference signal, for example by way of the signal characteristic. Alternatively, the predetermined condition may also be a time specification. For example, it would be conceivable to trigger the camera at intervals, for example every 30 seconds. Of course, other conditions would also be conceivable. Alternatively, it would be conceivable for the control device to trigger the camera in a manner depending on the user, for example upon a button input by the user. 
         [0019]    It is also advantageous if the predetermined condition can be set in a manner specific to the user, in particular during the operation of the directional antenna. This ensures that the control device is adapted to specific circumstances, such as environmental circumstances (for example position-finding in a closed building, in urban environments etc.). 
         [0020]    In a further embodiment, the directional antenna comprises a distance measurement device. By means of the distance measurement device, a distance between the directional antenna and the interference source can be determined, making it possible to improve the manner in which the position of the interference source is determined. In addition, this makes it possible to evaluate the quality of the emitted interference signal received by the directional antenna in a more effective manner. Preferably, the distance measurement device is designed as a directional microphone. A directional microphone is a type of microphone which primarily captures the frontally incident sound and thus has a directional characteristic. Sound from other directions is converted into electrical signals in a more attenuated manner. By means of a directional microphone, the distance can be determined from a difference in delay time between the electromagnetic signal and a sound signal which was emitted at the same time as the electromagnetic signal from the interference source. 
         [0021]    In a further embodiment, a directional antenna of this type is provided which is designed for receiving electromagnetic signals in a frequency range between 9 kHz and 7.5 GHz. Preferably, there are different types of directional antenna for interference signals of different frequencies. It is particularly advantageous if the directional antenna is configured for receiving electromagnetic signals in a frequency range between 9 kHz and 20 MHz and/or between 20 MHz and 200 MHz and/or between 200 MHz and 500 MHz and/or 500 MHz and 7.5 GHz. 
         [0022]    In a particularly preferred development, the directional antenna according to the invention is designed to detect, locate and document interference signals emitted by an interference source. Preferably, this is carried out fully automatically by involving the control device. The term “documenting” refers for example to storing all of the detected data relating to the interference source. 
         [0023]    In another preferred embodiment of the measurement arrangement, an input device is provided so as to document further information, for example on the position, nature, type etc, of the interference source, as a result of user input. The input device may typically be designed as a button, keypad, touchpad, haptic sensor, a microphone having speech recognition, gesture recognition device etc. In this way, additional information, for example regarding the quality of the data or regarding a description of various relevant interference sources, observations by the user etc, can be recorded in a particularly simple manner and assigned to the captured data. 
         [0024]    In a further embodiment of the measurement arrangement, a control device is provided so as to assign the user-specific inputs to the captured image information and/or to the detected position-finding data. In this way, the detected information, such as the detected position-finding data, image information, GPS data, time information, user inputs etc. can be stored as associated information. 
         [0025]    In a further embodiment of the measurement arrangement, a display device is provided. By means of the display device, the detected information, such as the detected position-finding data, image information, GPS data, time information, user inputs etc. can be displayed individually or as associated information. The display device is for example formed as a monitor, display, screen, such as an LCD screen, plasma screen, FED screen, CRT screen and the like. 
         [0026]    The above configurations and developments can be combined with one another in any desired manner, within reason. Further possible configurations, developments and implementations of the invention also comprise combinations not explicitly mentioned of features of the invention which are set out above or in the following in relation to the embodiments. In particular, in this context, a person skilled in the art will also add individual aspects as improvements or additions to the relevant basic form of the present invention. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0027]    In the following, the present invention is described in greater detail by way of the embodiments shown in the schematic drawings, in which: 
           [0028]      FIG. 1  shows a first, general embodiment of a directional antenna according to the invention; 
           [0029]      FIG. 2-5  show further embodiments of a directional antenna according to the invention; 
           [0030]      FIG. 6  is a flow chart illustrating the method according to the invention; 
           [0031]      FIG. 7A-7D  show further embodiments of a directional antenna according to the invention; 
           [0032]      FIG. 8  shows a further embodiment of a measurement arrangement according to the invention. 
       
    
    
       [0033]    The accompanying drawings are intended to give an improved understanding of the embodiments of the invention. They illustrate embodiments and are intended to clarify principles and concepts behind the invention, in conjunction with the description. Other embodiments and many of the stated advantages can be seen from the drawings. The elements of the drawings are not necessarily shown to scale with one another. 
         [0034]    In the drawings, like, functionally identical and equivalent elements, features and components are provided with like reference numerals unless stated otherwise. 
       DESCRIPTION OF EMBODIMENTS 
       [0035]      FIG. 1  is a schematic view of a first, general embodiment of a directional antenna  100  according to the invention for locating radio-frequency interference sources. The directional antenna  100  is designed to receive and analyse an electromagnetic signal  102  which is generated and broadcast for example by an interference source  101  such as a defective household appliance, a mobile radio transmitter or the like. 
         [0036]    The directional antenna  100  according to the invention comprises a camera  103 , which may be an analogue camera or digital camera and which is for example embedded in the housing  104  of the directional antenna  100 . By means of the directional antenna  100  according to the invention comprising an integrated camera  103 , a functionally expanded directional antenna  100  is provided. In particular, the directional antenna  100  makes it possible to document the location, the environment, the exact position, the type and nature etc. of the interference source  101  in a particularly efficient and convenient manner by the camera  103  capturing image information from the interference source  101  or the surroundings thereof. 
         [0037]    The camera  103  may be designed as a photo camera for capturing individual images or as a video camera for capturing image sequences. 
         [0038]      FIG. 2  is a schematic view of a further embodiment of a directional antenna  200  according to the invention. In this case, the directional antenna  100  comprises a storage medium  200  for storing the image information captured by the camera  103  and further information such as position-finding data. In the case of a digital camera  103 , the storage medium  200  may already be integrated into the camera  103 . In this case, the storage medium  200  is an electronic memory  200 , such as a DRAM, SRAM, graphical memory, memory card, hard disk or the like. It would also be conceivable for the storage medium  200  to be formed as an external memory and for example to be able to be coupled to the directional antenna  100  via an I/O interface (not shown). 
         [0039]    The directional antenna  100  further comprises a control device  201 , which is coupled both to the camera  103  and to the memory  200 . The control device  201  controls the functionality of the directional antenna  100  and the camera  103  and memory  200  thereof. For example, it may be provided that the control device  201  triggers automatically in a manner depending on a predetermined condition. The predetermined condition may for example be that of exceeding a particular predetermined threshold, for example relating to the amplitude, intensity, scattering and/or frequency of the detected electromagnetic interference signal  102 . 
         [0040]      FIG. 3  is a schematic view of a further embodiment of a directional antenna  100  according to the invention. In this case, in addition to the camera  103 , memory  200  and control device  201 , the directional antenna  100  comprises a GPS sensor  300  for determining the position of the directional antenna  100 . The GPS sensor  300  is coupled to the memory  200  so as to store the obtained position data therein. The GPS sensor  300  thus makes it possible for image information detected by the camera  103  and position-finding data detected by the directional antenna  100  each to be provided with a position stamp, in such a way that associated image and position-finding data can subsequently be identified in a simpler manner by way of the position stamp. 
         [0041]    The directional antenna  100  further comprises a device  301  for time detection. Since data which were detected at (virtually) the same time were generally also detected at (virtually) the same location, it is also possible to carry out particularly precise position assignment of the detected data using the device  301 . 
         [0042]    Furthermore, the directional antenna  100  comprises an actuation device  302  for actuating the camera  103 . In this embodiment, the actuation device  302  is designed as a trigger button  302 , by means of which the camera  103  is triggered by a user. However, the camera  103  could also be controlled by means of the actuation device  302 . 
         [0043]    The directional antenna  100  further comprises a directional microphone  303  for receiving a sound signal which is emitted by an interference source  101  at the same time as the electromagnetic interference signal  102 . By means of the directional microphone  303 , a difference in delay time between the delay time of the electromagnetic interference signal  102  and the sound signal is detected, by way of which the distance from the interference source  101  to the directional antenna  100  can be determined. 
         [0044]    For easier handling by a user, the directional antenna  100  is additionally equipped with a handle  304 . 
         [0045]      FIG. 4  is a schematic view of a first embodiment of a measurement arrangement  400  according to the invention for detecting and locating electrical radio-frequency interference source. The measurement arrangement  400  comprises a directional antenna  100  of the type disclosed above by way of  FIGS. 1 to 3 , and a spectrum analyser  401 . 
         [0046]    A spectrum analyser  401  is a measurement device used in electrical measurement for detecting and displaying a signal in the frequency range. The display is usually provided on a screen installed in the measuring device, the horizontal axis (x-axis) being the frequency axis and the amplitude of the signal being shown on the vertical axis (y-axis). The resulting image is referred to as a frequency spectrum. Spectrum analysers  401  are used inter alia in the field of high-frequency technology. 
         [0047]    Using the measurement arrangement  400  according to the invention, it is possible to initially detect and characterise an electromagnetic interference signal  102  by means of the spectrum analyser  401  and to subsequently locate the detected and characterised interference signal  102  by means of the directional antenna  100 . 
         [0048]    The measurement arrangement  400  may be formed in a single piece. In this case, the spectrum analyser  401  would already be integrated into the directional antenna  100  (or vice versa). However, it is advantageous if the measurement arrangement  400  is formed in two pieces, as is shown in  FIG. 4 . In this case, a first part of the measurement arrangement  400  comprises the directional antenna  100  and a second part of the measurement arrangement  400  comprises the spectrum analyser  401 . In this case, the directional antenna  100  and the spectrum analyser  401  are to be coupled to one another for example by means of a radio connection or a connection cable  402 . 
         [0049]      FIG. 5  shows a further embodiment of a measurement arrangement  400  according to the invention. In this case, the spectrum analyser  401  comprises an input device  500 , via which user-specific additional information can be inputted and can be stored together with the associated position-finding data and image information. In this case, the input device  500  comprises a keypad  501 , a microphone  502  for inputting a voice memo and a touchscreen  503 . 
         [0050]      FIG. 6  is a flow diagram illustrating the individual steps of the method according to the invention for measuring an electromagnetic signal emitted by an interference source. 
         [0051]    Initially, in a first step S 1 , an electromagnetic interference signal generated by an interference source is detected and evaluated, for example by analysing a characteristic of the interference signal in terms of the frequency, amplitude, intensity etc. thereof. 
         [0052]    In a further step S 2 , a direction of incidence of the detected electromagnetic signal is determined. 
         [0053]    The steps S 1 , S 2  may be repeated iteratively, in such a way that the user can optimally approximate the direction of incidence of the detected electromagnetic signal. 
         [0054]    During or subsequent to these search and optimisation steps S 1  and S 2 , in step S 3  at least one image of the environment in which the electromagnetic signal was detected is captured. 
         [0055]    In a subsequent step S 4 , the detected data and information captured and measured in steps S 1 , S 2  and S 3  are stored. To reduce post-processing work, associated data are stored cohesively or labelled in such a way that, after storage, associated data can be detected by a sorting algorithm as being associated. 
         [0056]      FIG. 7A-7D  show further embodiments of a directional antenna  100  according to the invention. Instead of a GPS sensor  300 , as in the embodiment of  FIG. 3 , this directional antenna  100  is equipped with a compass  305  for position determination. 
         [0057]    The various directional antennae  100  of  FIG. 7A-7D  are distinguished by different receiving sensitivities towards the interference signals to be detected. Thus, for example, the directional antenna  100  in  FIG. 7A  is configured for a frequency range of 9 kHz to 20 MHz. The directional antenna  100  in  FIG. 7B  is configured for a frequency range of 200 MHz to 500 MHz. The directional antenna  100  in  FIG. 7C  is configured for a frequency range of 20 MHz to 200 MHz. The directional antenna  100  in  7 D is configured for a frequency range of 0.5 GHz to 7.5 GHz. 
         [0058]      FIG. 8  shows a further embodiment of a measurement arrangement  400  according to the invention comprising a spectrum analyser  401  and a directional antenna  100 . In this embodiment, in  FIG. 8 , the spectrum analyser  401  is connected to the directional antenna  100  via a coaxial cable  404 . Alternatively, wireless coupling of the spectrum analyser  401  and the directional antenna  100  may also be provided, for example by Bluetooth, IR, radio etc. 
         [0059]    In this case, the spectrum analyser  401  comprises an input device  500  in the form of a keypad  501 . In addition, a display  403  is provided, on which data from the interference signal which are detected by the directional antenna  100  are displayed. In this embodiment, the display  403  shows a frequency spectrum  405  of the detected interference signal. In addition, the signal intensity  406  detected by the spectrum analyser  401  is shown. Furthermore, the display  403  shows the position-finding data detected by the directional antenna  100  on an angle scale  407 . According to the invention, an image  408  captured by the camera  103  is now also shown on the display  403 . 
         [0060]    Although the present invention has been disclosed by way of preferred embodiments, it is not limited thereto, but can be modified in various ways. Thus, the detailed description of embodiments of the invention is merely exemplary in nature, and is not intended to limit the invention or the range of application or the applications of the invention. In particular, the values stated or shown in the embodiments are merely exemplary in nature and may vary depending on the field of application of the invention. 
       LIST OF REFERENCE NUMERALS 
       [0061]      100  Directional antenna 
         [0062]      101  Interference source 
         [0063]      102  Interference signal 
         [0064]      103  (Analogue or digital) camera 
         [0065]      104  Housing 
         [0066]      200  Memory 
         [0067]      201  Control device 
         [0068]      300  GPS sensor 
         [0069]      301  Device for time detection 
         [0070]      302  Actuation device 
         [0071]      303  Directional microphone, distance measurement device 
         [0072]      304  Handle 
         [0073]      305  Compass 
         [0074]      400  Measurement arrangement 
         [0075]      401  Spectrum analyser 
         [0076]      402  Connection cable 
         [0077]      403  Display 
         [0078]      404  Coaxial cable 
         [0079]      405  Frequency spectrum 
         [0080]      406  Intensity 
         [0081]      407  Angle scale 
         [0082]      408  (Camera) image 
         [0083]      500  input device 
         [0084]      501  Keypad 
         [0085]      502  Microphone 
         [0086]      503  Touchscreen 
         [0087]    S 1 -S 4  Steps