JP2006053010A - Electromagnetic field pattern measuring apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic field pattern measuring apparatus capable of appropriately measuring electromagnetic field patterns for every antenna to be tested even in the case that the height of the antennas to be tested have differences in elevation. <P>SOLUTION: The electromagnetic field pattern measuring apparatus is provided with an offset amount adjusting means 6 for adjusting the vertical position of an antenna guide means for test 4 for restricting the direction of movement of an antenna 3 for test along a circular arc to adjust the vertical position of the vertical position of an antenna guide means for test 4. Even in the case that the height of an antenna 13 to be tested has differences in elevation due to the size of a device 12 to which the antenna 13 to be tested is mounted, differences in antenna mounting position, etc., it is possible to accurately measure the reception level of the antenna 13 to be tested (at the time of down-link communications) and the reception level of the antenna 3 to be tested (at the time of up-link communications) by adjusting the center of a curvature of the arc along which the antenna 3 to be tested is moved to the height of the antenna to be tested 13 and maintaining a constant measuring distance, the distance separating the antenna to be tested 13 from the antenna 3 to be tested. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an improvement in an electromagnetic field pattern measuring apparatus that moves a test antenna around an antenna under test and measures the reception level of the antenna under test or the reception level of the test antenna for each position of the test antenna.

  Examples of this type of electromagnetic field pattern measuring device include an antenna measuring device as disclosed in Patent Literature 1, a radio wave propagation characteristic measuring device as disclosed in Patent Literature 2, or disclosed in Patent Literature 3. Such a directivity measuring device is known.

  The antenna measuring instrument disclosed in Patent Document 1 is such that an antenna to be tested is mounted on a stage and rotated 360 °, and an arm to which a test antenna is attached is centered on an axis orthogonal to the rotation axis of the stage at each rotational position of the stage. The propagation characteristics of the radio wave are measured by rotating 360 ° in an arc shape.

  In order to properly grasp the propagation characteristics of radio waves, it is necessary to measure the propagation characteristics under the conditions in which the antenna under test is actually used, and to accurately understand the propagation characteristics from the sampled data Therefore, it is necessary to clearly associate the relationship between the measurement data of the propagation characteristics and the measurement position. The propagation characteristic is usually measured while moving the test antenna along a spherical surface centered on the position of the antenna under test. Data representing this propagation characteristic is finally shown in Patent Document 3. As described above, it is generally created by plotting the reception sensitivity in a polar coordinate system for specifying the measurement position.

  Various types of communication devices, vehicles, airplanes, and the like are conceivable as devices equipped with antennas. Especially, in the case of vehicles, airplanes, etc., their sizes are various, and antenna mounting positions are also various. Therefore, even if these are placed on the stage under the same conditions, a considerable difference in height occurs in the height of the antenna with respect to the stage.

  As a result, when an antenna measuring device as disclosed in Patent Document 1 is used and measurement is performed by always rotating the arm to which the test antenna is attached about the same position, the test antenna is eccentric from the antenna under test. This causes a disadvantage that sampling of propagation characteristics with a constant distance, that is, a measurement distance between the antenna under test and the test antenna cannot be performed.

  As a means for adjusting the separation distance between the antenna under test and the test antenna, as disclosed in Patent Document 2, the height of the test antenna is adjusted by a lifting mechanism provided on the arm. Is known, but this is merely a moving of the test antenna on the arm in the vertical direction along the arm. Therefore, even if this arm is configured to sample the propagation characteristics while rotating around the base, only the magnitude of the curvature of the arc serving as the movement trajectory of the test antenna changes. Since the center vertical position itself cannot be adjusted, if there is a difference in the height of the antenna under test, the propagation characteristics cannot be sampled with the measurement distance kept constant as described above.

  On the other hand, the directivity measuring apparatus disclosed in Patent Document 3 uses an articulated robot to move the test antenna along a predetermined arc while maintaining the posture of the test antenna. Therefore, in theory, it is possible to cope with the difference in the antenna mounting position and height by changing the playback program according to the mounting position and height of the antenna under test.

  However, there are drawbacks that require complicated teaching operations and program editing work, and as a practical problem, the size of an articulated robot that has been put into practical use is not limited to antennas installed on large vehicles or airplanes. There is a problem that enormous costs are required to realize the equipment even if technically possible.

JP 2001-133495 A JP-A-9-319901 JP-A-5-26931

  Therefore, an object of the present invention is to improve the inconvenience of the prior art, without requiring complicated teaching operation and program editing work, and having a height difference in height of the antenna under test with respect to the stage. Another object of the present invention is to provide an electromagnetic field pattern measuring apparatus capable of appropriately measuring an electromagnetic field pattern for each antenna under test.

The present invention moves a test antenna that transmits or receives radio waves to and from the antenna under test around the antenna under test, and receives the reception level of the antenna under test or the test antenna for each position of the test antenna. An electromagnetic field pattern measuring apparatus for measuring a reception level, in order to achieve the above-mentioned problem,
A stage for mounting a device on which the antenna under test is mounted;
A test antenna guide means for maintaining the posture of the test antenna with respect to the antenna under test substantially constant and regulating the moving direction of the test antenna along a concave arc downward in a space above the stage;
A test antenna driving means for moving the test antenna along a direction regulated by the test antenna guide means;
An offset amount adjusting means for adjusting the vertical position of the test antenna guide means is provided.

The test antenna guide means maintains the posture of the test antenna with respect to the antenna under test in a substantially constant state, and restricts the moving direction of the test antenna along a concave arc downward in a space above the stage.
The test antenna driving means moves the test antenna along a direction defined by the test antenna guide means, that is, along a concave arc.
Since the vertical position of the test antenna guide means can be adjusted by the offset amount adjustment means, even if there is a height difference in the height of the antenna under test relative to the stage, the curvature of the arc in which the test antenna moves is adjusted. With the center always adjusted to the height of the antenna under test, that is, with the measurement distance that is the distance between the antenna under test and the test antenna constant, the reception level of the antenna under test and the reception of the test antenna Level can be measured.

More specifically, for example, the test antenna guide means is configured by an arm that is rotatable in a vertical plane with one end as a rotation center and has a directivity toward the rotation center attached to the other end. ,
The test antenna driving means is constituted by rotation driving means for rotating the arm around the rotation center,
The offset amount adjusting means may be constituted by an elevating mechanism that adjusts the position of the rotation center of the arm up and down.

When such a configuration is applied, when the test antenna driving means is operated, the arm to which the test antenna is attached rotates in the vertical plane with its one end as the rotation center. Since the test antenna is attached to the other end of the arm, the test antenna moves along an arc that is the movement trajectory of the other end of the arm, and the attitude of the test antenna is always without special posture control. The directivity is held so as to go to the center of rotation of the arm, that is, where the test antenna should be.
Similarly to the above, since the vertical position of the arm serving as the test antenna guide means can be adjusted by the offset amount adjusting means, the test antenna can be used even when there is a height difference in the height of the antenna under test relative to the stage. The center of curvature of the arc of movement, that is, the center of rotation of the arm, is always adjusted to the height of the antenna under test, and the antenna under test is received with the measurement distance, which is the distance between the antenna under test and the antenna under test, being constant. The level and the reception level of the test antenna can be measured, which is particularly advantageous in that the structure is simple.

  Further, the elevating mechanism can be arranged at a position below the stage, and an arm storing groove for storing the arm in a substantially horizontal state can be formed around the stage.

  When such a configuration is applied, the arm can be stored in a state where it is stored in the arm storing groove, so that the structure of the arm is large in order to cope with the antenna under test installed in a large vehicle or airplane. Even if it is made into a case, the floor space at the time of non-measurement can be used effectively.

  Further, it is desirable that the test antenna guide means be made of a material having a lower electromagnetic wave reflectivity and specific gravity than a metal material.

By forming the test antenna guide means with a material having a low electromagnetic wave reflectivity, the intensity of the reflected wave from the test antenna guide means for restricting the moving direction of the test antenna can be reduced. The measurement accuracy of the reception level and the reception level of the test antenna is improved.
Further, by forming the test antenna guide means with a material having a small specific gravity, the load on the rotation drive means is reduced particularly when the test antenna guide means is constituted by an arm, and the rotation drive means is small, light and low in weight. Since the strength is sufficient, the manufacturing cost of the apparatus can be reduced.
In addition, as the weight of the arm is reduced, the counterweight required to maintain the posture of the arm becomes unnecessary or downsizing, so that it is not necessary to dig a floor surface to allow rotation of the force unweight. . For this reason, the cost required for the installation of the arm is reduced, and the additional installation of the arm to the existing equipment, which has been difficult in the past, is also possible.

  As a material for forming the test antenna guide means, fiber-reinforced plastic (hereinafter referred to as FRP) is particularly suitable.

When FRP is used, the intensity of the reflected wave from the test antenna guide means is about several percent as compared with the case where a metal material such as iron is used, and the intensity of the reflected wave can be greatly reduced. This significantly improves the measurement accuracy of the reception level of the antenna under test and the reception level of the test antenna.
In addition, it is possible to improve the performance further by attaching a radio wave absorber to the surface of the test antenna guide means made of FRP, and for high-accuracy measurement in which the influence of slight reflected waves from FRP becomes a problem. Can also be dealt with.
When an arm serving as an antenna guide means for testing is configured using FRP, the weight of the arm can be reduced to about 1/3 compared with the case where a metal material such as iron is used, and it is rotationally driven. The load on the means is greatly reduced.

  The electromagnetic field pattern measuring apparatus of the present invention is provided with offset amount adjusting means for adjusting the vertical position of the test antenna guide means that regulates the moving direction of the test antenna along the arc, and the vertical position of the test antenna guide means is adjusted. Even if the height of the antenna under test relative to the stage is different depending on the size of the device mounting the antenna under test and the difference in the antenna mounting position, the test antenna can be adjusted. The reception level and test of the antenna under test with the center of curvature of the moving arc aligned with the height of the antenna under test, that is, with the measurement distance that is the distance between the antenna under test and the test antenna constant. It is possible to accurately measure the reception level of the antenna.

  In particular, the test antenna guide means is constituted by an arm having a test antenna that can be rotated in a vertical plane with one end as a rotation center and has directivity toward the rotation center. The posture of the test antenna with respect to the antenna under test can be held substantially constant without requiring operation, program editing work, or special posture control, thereby simplifying the structure of the apparatus and reducing manufacturing costs. .

  Furthermore, the arm can be stored by disposing an elevating mechanism serving as an offset amount adjusting means at a position below the stage and forming an arm storing groove for storing the arm in a substantially horizontal state around the stage. Even when the arm structure is enlarged to cope with large vehicles and airplanes, the floor space can be effectively used during non-measurement.

In addition, since the test antenna guide means is made of a material whose electromagnetic wave reflectivity and specific gravity is smaller than that of a metal material, the intensity of the reflected wave is reduced to reduce the reception level of the antenna under test and the reception level of the test antenna. Measurement accuracy can be improved. Especially, when the test antenna guide means is constituted by an arm, the load of the rotation drive means is reduced, so that the rotation drive means can be small, light and low in strength. Thus, the manufacturing cost of the apparatus can be reduced.
Also, as the weight of the arm is reduced, the counterweight required to maintain the posture of the arm is also eliminated or reduced in size, so it is not necessary to dig a floor surface to allow the counterweight to rotate. The cost required to install the arm has been reduced, and it has also become possible to install the arm on the existing equipment, which has been difficult in the past.

  In particular, when fiber, reinforced plastic is used as the material for forming the test antenna guide means, the intensity of the reflected wave from the test antenna guide means is higher than when using a metal material such as iron. The intensity of the reflected wave can be greatly reduced, and the measurement accuracy of the reception level of the antenna under test and the reception level of the test antenna is remarkably improved, and it becomes a test antenna guide means. Since the weight of the arm can be reduced to about 1/3 compared with the case where a metal material such as iron is used, the load on the rotation driving means is greatly reduced.

  Next, the best mode for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing an outline of a configuration of an electromagnetic field pattern measuring apparatus according to an embodiment to which the present invention is applied.

  This electromagnetic field pattern measuring apparatus 1 has a stage 2 for mounting a device 12 such as a vehicle on which an antenna under test 13 is mounted, and a posture of the test antenna 3 with respect to the antenna under test 13 mounted on the device 12. The test antenna guide means 4 that is held constant and restricts the moving direction of the test antenna 3 along the concave arc downward in the space above the stage 2, and is regulated by the test antenna guide means 4. The test antenna drive means 5 and 5 for moving the test antenna 3 along the measured direction and the offset amount adjusting means 6 and 6 for adjusting the vertical position of the test antenna guide means 4 are provided.

  Among these, the test antenna guide means 4 is constituted by an arm 9 composed of struts 7, 7 on both sides and a beam-like member 8 connecting the tips of the struts 7, 7. The arm 9 can be rotated in the vertical plane with the lower end portion which is one end thereof as the rotation center C, and the test antenna 3 having directivity toward the rotation center C is provided on the beam-like member 8 located at the other end. It is attached.

  The test antenna 3 is configured as a reception antenna if the antenna under test 13 mounted on the device 12 is for transmission, and the antenna under test 13 mounted on the device 12 is for reception. If the antenna under test 13 mounted on the apparatus 12 is for transmission / reception, it is configured as a transmission / reception antenna.

  The pipe-structured columns 7 and 7 and the beam-shaped member 8 constituting the arm 9 are both formed of FRP, and the intensity of the reflected wave from the arm 9 functioning as the test antenna guide means 4 is a metal material such as iron. Compared to the case of using a metal material, the weight is about several percent, and the weight is reduced to about 1/3 compared to the case of using a metal material such as iron.

  The test antenna drive means 5 and 5 for moving the test antenna 3 along the direction regulated by the test antenna guide means 4 are connected to the arm 9 at the position of the rotation center C, and this rotation center. It is comprised by the rotational drive means 10 and 10 which rotate the arm 9 around C. As shown in FIG. The rotation driving means 10 can be constituted by a servo motor or a stepping motor that rotates synchronously, or a geared motor using these as a driving source. In this embodiment, the weight of the arm 9 described above reduces the size of the servo motor, stepping motor, and the like so that a small, low torque type is used, and the counterweight required for maintaining the posture of the arm 9 is extended to the lower end of the arm 9. There is no need to provide it. Therefore, the excavation of the floor surface for allowing the rotation of the force unweight is unnecessary, the cost required for installing the arm 9 is reduced, and the arm 9 to the existing equipment, which has been difficult in the past, can be reduced. Additional installation is possible.

  Offset amount adjusting means 6 and 6 for adjusting the position of the rotation center C of the arm 9 constituting the test antenna guide means 4 up and down move the rotation drive means 10 and 10 connected to the rotation center C of the arm 9 up and down. It is comprised by the raising / lowering mechanisms 11 and 11 to move. The elevating mechanisms 11 and 11 can be constituted by a screw jack type equipped with a ball nut & screw driven by a synchronously rotating servo motor or a stepping motor, or a hydraulic jack using a hydraulic circuit.

  In the above configuration, when the rotary drive means 10 and 10 constituting the test antenna drive means 5 and 5 are operated in synchronization, the arm 9 to which the test antenna 3 is attached has a vertical plane with its one end as the rotation center C. Rotate within. Since the test antenna 3 is attached to the beam-like member 8 located at the other end of the arm 9, the test antenna 3 is recessed in the direction restricted by the rotational movement of the arm 9, that is, the movement locus of the other end of the arm 9. The attitude of the test antenna 3 does not require any special attitude control, and its directivity is always the center of rotation of the arm 9, that is, where the test antenna 13 should be present. Hold to head towards.

  The vertical position of the arm 9 constituting the test antenna guide means 4, that is, the vertical position of the rotation center C is synchronized with the elevating mechanisms 11, 11 installed with the rotation driving means 10, 10 connected to the rotation center C of the arm 9. Since it is easily adjusted by raising and lowering, the height of the antenna under test 13 relative to the stage 2 due to the size of the device 12 such as a vehicle or the difference in the mounting position of the antenna under test 13 with respect to the device 12 Even if there is a height difference, the distance from the antenna under test 13 to the test antenna 3 with the center of the curvature of the arc in which the test antenna 3 moves coincides with the position of the antenna under test 13, that is, the measurement distance. Can be accurately measured in a state in which the reception level of the antenna under test 13 and the reception level of the test antenna 3 are measured.

  Instead of adjusting the vertical position of the arm 9 with the elevating mechanisms 11, 11, the stage 2 can be moved up and down to adjust the height of the rotation center C of the arm 9 to the position of the antenna under test 13. Since many of the devices 12 to be mounted are heavy, such as a vehicle, it is more advantageous in terms of required torque to adjust the vertical position of the lighter arm 9 than to move the stage 2 up and down. . Further, when the stage 2 is moved up and down, a relative position change occurs between a device 12 such as a vehicle in which the antenna under test 13 is installed and the surrounding floor surface (road surface), and the antenna under test 13 is actually used. Although it becomes difficult to measure the characteristics, when the vertical position of the arm 9 is adjusted, there is no change in the relative position between the device 12 such as the vehicle on which the antenna under test 13 is installed and the surrounding floor surface. The characteristics of the antenna under test 13 can be measured in a situation closer to the actual use state, which is advantageous in terms of measurement accuracy.

  In addition, the measurement accuracy of the reception level of the antenna under test 13 and the reception level of the test antenna 3 is improved by forming the arm 9 from FRP to reduce the intensity of the reflected wave.

  In addition, it is possible to further improve performance against disturbance by attaching a radio wave absorber to the surface of the arm 9 made of FRP, and also for high-precision measurement in which the influence of slight reflected waves from the FRP becomes a problem. Can be dealt with.

Here, the arm 9 that rotates in the vertical plane with one end as the center of rotation C is shown as an example of the test antenna guide means 4, but in addition to this, for example, a rack-like shape bent downwardly in a concave shape The path regulating means is used as a test antenna guide means, and a slider (runner) in which a pinion driven by a servo motor or the like is engaged with the rack is movably mounted inside the curvature of the path regulating means. The test antenna 3 may be attached to the slider.
The test antenna 3 is the same as that of the above-described embodiment in that the test antenna 3 moves in an arc along the test antenna guide means and the attitude of the test antenna 3 with respect to the center of curvature of the arc is constant.
However, in this case, the test antenna driving means is constituted by a servo motor in the slider, and the offset amount adjusting means is constituted by an elevating mechanism for moving the rack-shaped path regulating means attached with the slider up and down.

  FIG. 2 is a perspective view showing an outline of the configuration of the electromagnetic field pattern measuring apparatus 14 of another embodiment.

  By configuring the beam-like member 15 of the arm 9 by a combination of an F-shaped L-shaped angle or a thin prism, the arm 9 can be further reduced in weight while maintaining sufficient rigidity. Further, although not particularly shown here, the support columns 7 and 7 of the arm 9 may be constituted by an L-shaped angle or a combination of thin squares like the beam-like member 15 of FIG.

  FIG. 3 is a perspective view showing an outline of the configuration of the electromagnetic field pattern measuring apparatus 16 of still another embodiment.

  In this embodiment, the rotation center C of the lower end portion of the arm 9 constituting the test antenna guide means 4 is rotatably held by the shaft support plates 17, 17. The shaft support plates 17, 17 are held by the offset amount adjusting means 6. , 6 is moved up and down by the elevating mechanisms 11, 11 to adjust the height of the rotation center C of the arm 9.

  The test antenna driving means 5 for moving the test antenna 3 along the direction of movement regulated by the arm 9 includes a traction rope 18 connected to the beam-like member 8 of the arm 9 and a winding of the traction rope 18. An electric winch 19 for performing take-up / rewinding, and a pulley 20 installed on the top of the building in order to optimize the towing direction of the towing rope 18 with respect to the arm 9, and the towing rope using the electric winch 19 By the 18 winding / rewinding operations, the rotation operation of the arm 9 is realized in a range from the state in which the arm 9 is laid down substantially horizontally to standing upright.

  In this embodiment, the amount of rotation of the arm 9 changes according to the posture of the arm 9 even when the winding / rewinding amount of the tow rope 18 is constant, and the arm is also moved by the vertical movement of the elevating mechanisms 11, 11. Therefore, it is difficult to specify the posture of the arm 9 appropriately even if the rotation amount of the electric winch 19 is controlled by an open loop. For this reason, the shaft support plate 17 is provided with a rotation angle detecting means such as a rotary encoder for detecting the rotation angle of the arm 9, and the rotation angle of the arm 9 based on a command from a control device (not shown) is controlled. This is performed with reference to a feedback signal from the rotation angle detecting means.

  In this embodiment, it is not necessary to provide a metal part such as a motor or a gear at the base of the arm 9, so that the effect of reducing disturbance due to reflection or radiation of electromagnetic waves is greater than that of the structure shown in FIGS. There is an advantage that measurement accuracy is further improved.

  FIG. 4 is a side view showing an outline of the configuration of the electromagnetic field pattern measurement apparatus 21 of another embodiment, and FIG. 5 is a plan view showing the outline of the configuration of the electromagnetic field pattern measurement apparatus 21 of the embodiment. .

  The structure of the arm 9 including the columns 7 and 7 and the beam-shaped member 8, the structure of the rotation driving means 10 that functions as the test antenna driving means 5, the structure of the lifting mechanism 11 that functions as the offset amount adjusting means 6, and the beam The mounting structure of the test antenna 3 to the member 8 is the same as that of the electromagnetic field pattern measuring apparatus 1 shown in FIG. 1, and therefore, the same reference numerals are used in FIG. 4 and FIG. Description is omitted.

  As shown in FIG. 5, the stage 22 of this embodiment is constituted by a rotary turntable. Further, as shown in FIG. 4, the elevating mechanisms 11 and 11 located on both sides of the stage 22 are installed in a space formed by digging the floor surface of the test site, and are located below the stage 22. Further, an arm storing groove 23 for storing the arm 9 in a substantially horizontal state is formed around the stage 22.

  FIG. 6 shows a state in which the elevating mechanisms 11 and 11 are completely lowered and the arm 9 is laid down almost horizontally. In this state, the rotation driving means 10 and 10 and the elevating mechanisms 11 and 11 are below the floor surface. And the arm 9 is stored in the arm storing groove 23. Reference numeral 24 denotes an anechoic chamber for eliminating disturbances that adversely affect the measurement.

  An outline of the configuration of the controller 25 for controlling the entire electromagnetic field pattern measuring apparatus 21 is shown in FIG.

  The main part of the controller 25 includes a CPU 26 for arithmetic processing, a ROM 27 storing a control program for the CPU 26, a RAM 28 used for temporary storage of arithmetic data, a hard disk for storing measurement data of reception levels, and the like. The storage device 29 is configured.

  Servo motors M1 and M2 serving as driving sources for the rotation driving means 10 and 10 are connected to the input / output circuit 30 of the controller 25 via a synchronizing circuit 31 and axis control circuits 32 and 33, and a movement command output from the CPU 26 is connected. Based on the pulse and the feedback pulse from the rotary encoder P1 of the servo motor M1, the synchronization circuit 31 synchronously controls the servo motors M1 and M2 via the axis control circuits 32 and 33. Similarly, servo motors M3 and M4 functioning as drive sources for the screw jack type lifting mechanisms 11 and 11 having ball nuts and screws and the like are connected via a synchronizing circuit 34 and shaft control circuits 35 and 36, and the CPU 26 The synchronization circuit 34 synchronously controls the servomotors M3 and M4 via the axis control circuits 35 and 36 based on the movement command pulse output from the servomotor M3 and the feedback pulse from the rotary encoder P3 of the servomotor M3. Yes. The servo motor M5 for rotating the stage 22 is driven and controlled by the axis control circuit 37 based on the movement command pulse output from the CPU 26 and the feedback pulse from the rotary encoder P5 of the servo motor M5.

  Further, a manual data input device 39 with a display device is connected to the interface 38 of the controller 25. Further, the test antenna side control device 40 connected to the test antenna 3 and the antenna under test 13 are connected to the interface 38. The connected antenna-under-test control device 41 is connected.

  If the antenna under test 13 is for transmission, the antenna under test side control device 41 includes a transmitter, and the test antenna side control device 40 includes a receiver. The reception level is input from the test antenna side control device 40 to the interface 38 of the controller 25 as reception level data. On the other hand, if the antenna under test 13 is for reception, the test antenna side control device 40 includes a transmitter, and the antenna under test control device 41 includes a receiver, and is received by this receiver. The radio wave reception level is input from the antenna under test control device 41 to the interface 38 of the controller 25 as reception level data. Further, if the antenna under test 13 is for transmission / reception, the test antenna side control device 40 and the antenna under test side control device 41 both include a transceiver, and receive radio waves received by these transceivers. The level is input to each interface 38 of the controller 25 as reception level data from each of the test antenna side control device 40 (during uplink communication) and the antenna under test side control device 41 (during downlink communication).

  FIG. 8 is a flowchart showing an outline of processing executed by the CPU 26 of the controller 25.

  Next, the overall operation of the electromagnetic field pattern measuring apparatus 21 in this embodiment will be briefly described with reference to FIG. However, at this stage, the arm 9 and the elevating mechanisms 11 and 11 are retracted to the retracted position as shown in FIG. 6, and the device 12 such as a vehicle on which the antenna under test 13 is mounted is already placed on the stage 22. It is assumed that the test antenna side control device 40 and the antenna under test side control device 41 are connected to the interface 38.

  Therefore, when the operator operates the manual data input device with display 39 and inputs a start command to the controller 25, the CPU 26 detects the input of the start command in the process of step S1, and first drives the servo motors M3 and M4. Then, after the elevating mechanisms 11 and 11 are raised from the position of FIG. 6 to the initial position as shown in FIG. 4 (step S2), a message for prompting an input operation of the offset amount is displayed. Is displayed on the monitor (step S3), and a standby state is entered in which the operator inputs an offset amount (step S4) or waits for an operator to input a measurement execution command (step S6). This initial position is a position where the upper ends of the elevating mechanisms 11 and 11 are at the same height as the surface of the stage 22, and is necessary for raising the elevating mechanisms 11 and 11 from the storage position in FIG. 6 to the initial position in FIG. The value of the movement command pulse is stored in advance in the ROM 27 as a parameter, and the CPU 26 reads out the movement command pulse (movement command value) in the process of step S5 and divides it to obtain a movement command pulse per unit time. (Speed command value) is output to the synchronizing circuit 31 at predetermined intervals corresponding to the unit time, and the synchronizing circuit 31 subtracts the feedback signal from the rotary encoder P1 from the integrated value of the movement command pulse to obtain an error value. The servo motors M3 and M4 are driven and controlled so that the error value (torque command value) becomes zero.

  Here, when the operator performs an input operation of the offset amount, the CPU 26 detects the input of the offset amount in the process of step S4, drives the servo motors M3 and M4 again, and moves the lifting mechanisms 11 and 11 to the offset amount. Is raised or lowered by an amount corresponding to (step S5). Except for the fact that an offset value corresponding to the movement command pulse required to raise the elevating mechanisms 11 and 11 is input from the outside, the contents of drive control of the servo motors M3 and M4 are the same as described above. is there.

  By adjusting the input offset value, the position of the center of rotation C of the arm 9 can be determined regardless of the height of the device 12 such as a vehicle or the attachment position of the antenna under test 13 to the device 12. Can be adjusted to the height of

  Next, when the operator operates the manual data input device with display 39 and inputs a measurement execution command, the CPU 26 detects the input of the measurement execution command in the process of step S6, and stores the rotational position of the arm 9 An initial value 0 is set in each of the storage register D1 and the rotational position storage register D2 that stores the rotational position of the stage 22 (steps S7 and S8). First, in this state, the first measurement of the reception level is performed. (Step S9), and receive level data input from the test antenna side control device 40 or the antenna under test side control device 41 via the interface 38, and the rotation angle D1 = [0] ° of the arm 9 and the stage. 22 is stored in the storage device 29 in correspondence with the rotation angle D2 = [0] ° (step S10). However, D1 = [0] ° is a state in which the arm 9 is horizontal as shown by a two-dot chain line in FIG. 4, and D2 = [0] ° is a vehicle or the like as shown in FIG. The apparatus 12 is in a state orthogonal to the beam-like member 8.

  Next, the CPU 26 drives the servo motor M5 to rotate the stage 22 by a minute rotation amount [ΔD2] ° (step S11), and increments the value of the rotation position storage register D2 by ΔD2 to increase the current rotation position of the stage 22. Is updated and stored (step S12), and it is determined whether or not the current rotational position of the stage 22 has reached [360] ° (step S13). The minute rotation amount ΔD2 of the stage 22 is, for example, a value such as [0.5] ° or [1] °, and is a value that is appropriately determined according to a request for mapping accuracy of measurement data of the reception level. This value is preferably set so that [360 / ΔD2] is an integer value. The value of ΔD2 is stored in advance in the ROM 27 as a parameter. The drive control of the servo motor M5 is the same as the drive control of the servo motors M3 and M4.

  Here, if the determination result in step S13 is true, that is, if it is clear that the accumulated rotation amount of the stage 22 has not reached [360] ° at the current stage, the CPU 26 performs step again. Returning to the process of S9, the processes of steps S9 to S13 are repeatedly executed in the same manner as described above.

  As a result, each of (D1, D2) = (0, 0) to (D1, D2) = (0, 360−ΔD2), that is, with the arm 9 held horizontally, the stage 22 is set to [0] °. The data of the reception level at each position when rotating from the position to the position of [360−ΔD2] ° in increments of [ΔD2] ° is stored in the storage device 29.

  When it is confirmed that the determination result in step S13 is false and the current rotational position of the stage 22 has reached [360] ° during the repeated execution of such processing, the CPU 26 stores the rotational position storage register D1. After the value is incremented by ΔD1, the next target rotational position of the arm 9 is updated and stored in the rotational position storage register D1 (step S14), and then the next target rotational position of the arm 9 exceeds [90] °. Is determined (step S15). The rotation amount [ΔD1] ° of the arm 9 is, for example, a value such as [0.5] ° or [1] °, and is a value that is appropriately determined according to a request for mapping accuracy of reception level measurement data. However, this value is preferably set so that [360 / ΔD1] is an integer value. The value of ΔD1 is stored in advance in the ROM 27 as a parameter.

  Here, when the determination result of step S15 is true, that is, when it is clear that the integrated rotation amount does not exceed [90] ° even if the arm 9 is further rotated by [ΔD1] °. The CPU 26 drives the servo motors M1 and M2 to rotate the arm 9 by a minute rotation amount [ΔD1] ° (step S16), returns to the process of step S8 again, and repeats the processes of steps S9 to S13. Are repeatedly executed in the same manner as described above. The drive control of the servo motors M1 and M2 is the same as the drive control of the servo motors M3 and M4.

  As a result, first, each of (D1, D2) = (ΔD1, 0) to (D1, D2) = (ΔD1, 360−ΔD2), that is, the arm 9 is raised and held by [ΔD1] ° from the horizontal state. In the state, when the stage 22 is rotated from the [0] ° position to the [360−ΔD2] ° position in steps of [ΔD2] °, the data of the reception level at each position is stored in the storage device 29 (step) S9 to step S13 are repeated).

  Thereafter, in the same manner as described above, the stage 22 is moved from the position of [0] ° to the position of [360−ΔD2] ° with the arm 9 raised from the horizontal state by [2 · ΔD1] ° and held at [ΔD2] °. , The stage 22 is set to [0] ° while the arm 9 is raised and held by [3 · ΔD1] ° from the horizontal state. From the position of [3] to the position of [360- [Delta] D2] [deg.] In steps of [[Delta] D2] [deg.] So that the data of the reception level at each position is stored in the storage device 29 is repeatedly executed.

  Then, in the last repetitive processing of Step S9 to Step S13, the stage 22 is moved from the position of [0] ° to [360−ΔD2] ° with the arm 9 raised by [90] ° from the horizontal state and held. A process of rotating the data in increments of [ΔD2] ° to the position and storing the data of the reception level at each position in the storage device 29 is executed.

  Thus, since the value of the rotational position storage register D1 has already reached [90] ° at the time when the determination result of step S13 becomes false in the repetitive processing of step S9 to step S13 performed at the end, the value has already reached [90] °. When the value of the rotational position storage register D1 is incremented by ΔD1 by executing the process of step S14, the determination result of step S15 becomes false, and the arm 9 is moved from the position [0] ° in the horizontal state by [ΔD1] ° by [90]. Rotate the stage 22 to the position of [°], rotate the stage 22 from the position of [0] ° to the position of [360−ΔD2] ° by [ΔD2] ° at each rotational position, and store the reception level data for each position in the storage device 29 All the processes to be stored in are completed.

  As a result, the reception level data in the upper half of the hemisphere centered on the position of the antenna 13 under test is sampled at a pitch of [ΔD1] ° in the latitude direction and [ΔD2] ° in the longitude direction to indicate the measurement position. It is stored in the storage device 29 together with the values D1 and D2.

  Finally, when the operator operates the manual data input device with display 39 and inputs a measurement end command to the controller 25, the CPU 26 detects the input of the measurement end command in the process of step S17, and the rotation drive means 10, Servo motors M1 and M2 functioning as drive sources 10 are driven to rotate the arm 9 in the reverse direction by [90] ° to return to the horizontal state (step S18), and further function as drive sources for the lifting mechanisms 11 and 11 The servo motors M3 and M4 are driven to lower the elevating mechanisms 11 and 11 from the initial position in FIG. 4 to the retracted position as shown in FIG. 6, and the elevating mechanisms 11 and 11 are stored in the dug in the floor of the test site. At the same time, the arm 9 is stored in the arm storing groove 23 (step S19).

  Thus, since the arm 9 can be stored in the state where it is stored in the arm storing groove 23, the structure of the arm 9 is used to cope with the antenna under test 13 attached to the apparatus 12 such as a large vehicle or an airplane. Even when the size of the test room is increased, the floor space of the test site at the time of non-measurement can be effectively used.

  In this embodiment, the stage 22 is rotated by [360] ° while the posture of the arm 9 is maintained, and the reception level is measured at each position. However, the arm 9 is moved by [90] while the rotational position of the stage 22 is maintained. It may be possible to measure the reception level at each position by rotating it, and the meaning of the obtained data is technically the same.

  Since the sampled reception level data is stored in the storage device 29 in an array of (D1, D2, reception level), this is read out and the monitor of the manual data input device with display 39 or XY If the reception level is plotted on a polar coordinate system using a plotter or the like, the propagation characteristics of radio waves can be easily grasped.

It is the perspective view shown about the outline of the structure of the electromagnetic field pattern measuring apparatus of one Embodiment to which this invention is applied. It is the perspective view shown about the outline of the structure of the electromagnetic field pattern measuring apparatus of another one Example. (Example 1) It is the perspective view shown about the outline of the structure of the electromagnetic field pattern measuring apparatus of another one Example. (Example 2) It is the side view shown about the outline of the composition of the electromagnetic field pattern measuring device of another example. Example 3 It is the top view shown about the outline of the structure of the electromagnetic field pattern measuring apparatus of the Example. It is the side view shown about the storage state of the electromagnetic field pattern measuring apparatus of the Example. Example 3 It is the functional block diagram shown about the outline of the structure of the controller which controls the electromagnetic field pattern measuring apparatus of the Example. Example 3 It is the flowchart shown about the outline of the process which CPU of a controller performs. Example 3

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electromagnetic-field pattern measuring apparatus 2 Stage 3 Test antenna 4 Test antenna guide means 5 Test antenna drive means 6 Offset amount adjustment means 7 Support | pillar 8 Beam-shaped member 9 Arm 10 Rotation drive means 11 Lifting mechanism 12 Devices 13 such as a vehicle Antenna to be tested 14 Electromagnetic field pattern measuring device 15 Beam-shaped member 16 Electromagnetic field pattern measuring device 17 Axial support plate 18 Towing rope 19 Electric winch 20 Pulley 21 Electromagnetic field pattern measuring device 22 Stage 23 Arm storing groove 24 Electromagnetic anechoic chamber 25 Controller 26 CPU
27 ROM
28 RAM
29 Storage device 30 Input / output circuit 31 Synchronous circuit 32, 33 Axis control circuit 34 Synchronous circuit 35, 36, 37 Axis control circuit 38 Interface 39 Manual data input device 40 with display device Test antenna side control device 41 Antenna under test control Device C Arm rotation center M1, M2, M3, M4, M5 Servo motor P1, P3, P5 Rotary encoder

Claims (5)

A test antenna that transmits or receives radio waves to the antenna under test is moved around the antenna under test, and the reception level of the antenna under test or the reception level of the test antenna is set for each position of the test antenna. An electromagnetic field pattern measuring device for measuring,
A stage for mounting a device on which the antenna under test is mounted;
A test antenna guide that maintains a substantially constant posture of the test antenna with respect to the antenna under test and that regulates the moving direction of the test antenna along a concave arc downward in a space above the stage. Means,
A test antenna driving means for moving the test antenna along a direction regulated by the test antenna guide means;
An electromagnetic field pattern measuring apparatus comprising: an offset amount adjusting means for adjusting a vertical position of the test antenna guide means. The test antenna guide means is constituted by an arm which is rotatable in a vertical plane with one end as a rotation center and has the directivity toward the rotation center and attached to the other end.
The test antenna driving means is constituted by rotation driving means for rotating the arm around the rotation center,
2. The electromagnetic field pattern measuring apparatus according to claim 1, wherein the offset amount adjusting means is configured by an elevating mechanism that adjusts the position of the center of rotation of the arm up and down.   The arm raising groove is provided at a position below the stage, and an arm storing groove for storing the arm in a substantially horizontal state is formed around the stage. Electromagnetic field pattern measuring device.   4. The electromagnetic field pattern measuring apparatus according to claim 1, wherein the test antenna guide means is made of a material having a reflectance and specific gravity of electromagnetic waves smaller than that of a metal material.   4. The electromagnetic field pattern measuring apparatus according to claim 1, wherein the test antenna guide means is made of fiber reinforced plastic.

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