JP2009194808A - Polarization plane control antenna, and method of calibrating polarization plane control antenna - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polarization plane control antenna which is capable of performing calibration inexpensively and is suitable for use under a mobile environment. <P>SOLUTION: A polarization plane control antenna includes: a distribution unit for distributing an input signal to two paths on the basis of a set polarization angle; a balance circuit including a first 90° hybrid and a second 90° hybrid connected with an output of the distribution unit; a polarization shared antenna which transmits an output of the second 90° hybrid with orthogonal polarized waves; first and second amplitude/phase control unit for changing amplitudes and phases of respective signals converted by the first 90° hybrid; a control unit which sets the polarization angle of the distribution unit and sets gain coefficients and phase coefficients of the first and second amplitude/phase control units; a means which is connected with the output of the second 90° hybrid and extracts a calibration signal flowing in the output; and a means for measuring a level of the extracted calibration signal. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a transmission antenna in a wireless communication system, and more particularly to an antenna that is used for a mobile communication satellite or the like and that electrically controls a polarization plane, and a calibration method for the antenna.

  In order to form a desired polarization plane, a polarization plane control antenna that can electrically control the polarization plane needs to excite each input terminal for polarization orthogonal to each other with a predetermined amplitude and phase. The signal processing for beam formation in the polarization plane control antenna is the same as that of the conventional phased array antenna, and the calibration method of the phased array antenna having two paths is described in, for example, Non-Patent Document 1 and Non-Patent Document 2. Has been.

  The configurations described in Non-Patent Document 1 and Non-Patent Document 2 control the pass characteristics of the beam forming apparatus so as to be in an equal amplitude and an equal phase state. As shown in FIG. The relative amplitude and phase are obtained by sequentially measuring the passing amplitude and phase between the input terminal of the beam forming device and each element antenna, and thereafter the amplitude and phase error compensation is performed in the beam forming device.

Sawada et al., “System Test Summary Report for Engineering Test Satellite VIII (KIKU No. 8) Communication System Mission System”, 51st Space Science and Technology Conference, 1J12, October 2007 Suzuki et al., "Outline of beam forming device type 2 mounted on technology test satellite VIII and confirmation of basic operation", 51st Space Science and Technology Union Conference, 1J14, October 2007 Egami et al., “Multi-terminal power combining system and multi-beam transmission system”, IEICE Transactions, Vol. J69-B, no. 2, pp. 206-212

  In the prior art method, in order to measure the passing amplitude and phase, an expensive microwave band measuring instrument, specifically, a signal generator, a spectrum analyzer, a frequency converter in addition to the vector network analyzer shown in FIG. , Variable phase shifter, variable attenuator, etc. are required. Further, when the antenna is used in a mobile environment, it is necessary to always provide these measuring instruments. However, the vector network analyzer and the like are generally heavy and large in size.

  Therefore, an object of the present invention is to provide a polarization plane control antenna that can be calibrated at a lower cost than the prior art and is suitable for use in a mobile environment, and a calibration method for the polarization plane control antenna.

According to the calibration method of the polarization plane control antenna in the present invention,
A distribution unit that distributes a signal input from the first input terminal to two paths based on the set polarization angle; and a first 90-degree hybrid that converts a signal of each path distributed by the distribution unit; The second 90-degree hybrid that reconverts the signal of each path converted by the first 90-degree hybrid and the signal of each path output by the second 90-degree hybrid are transmitted with orthogonal polarizations, respectively. And a first and second amplitude / phase control unit that are provided between the first 90-degree hybrid and the second 90-degree hybrid and change the amplitude and phase of the signal of each path. The polarization plane control antenna is calibrated and the distribution unit is set with a polarization angle value that allows a calibration signal input to the first input terminal to be input only to one input terminal of the dual-polarization antenna. , First amplitude position A first step of setting the phase change amount and the gain in the control unit and the second amplitude phase control unit to be the same; a calibration signal is input to the first input terminal; and the first or second amplitude phase control unit The phase change amount of the first and second amplitude phase control units when the calibration signal input to the other input terminal of the polarization sharing antenna is minimized is changed to The second step of setting the second amplitude phase control unit and the second amplitude phase in a state where the calibration signal is input to the first input terminal and the gain of the first amplitude phase control unit is set to 1. While the gain of the control unit is changed from 0 to 1, and the gain of the second amplitude phase control unit is set to 1, the gain of the first amplitude phase control unit is changed from 0 to 1, and First and second amplitudes when the calibration signal input to the other input terminal is minimized The gain of the phase control unit, characterized in that it comprises a third step of setting the first and second amplitude-phase control section.

According to another embodiment of the calibration method of the present invention,
The distribution unit has a second input terminal for a signal to be transmitted with a polarization orthogonal to the signal input to the first input terminal, and the signal input to the second input terminal is set. Distribution to the two paths based on the polarization angle, and after execution of the first step to the third step, the calibration signal input destination is the second input terminal, and the first step to the third step. It is also preferable to execute the above step again and set the average values of the gain and phase change amount of the first and second amplitude phase control units obtained in each execution to the first and second amplitude phase control units. .

According to another embodiment of the calibration method of the present invention,
The polarization plane control antenna is configured such that the amplitude and phase of the signal of each path is between the distribution unit and the first 90-degree hybrid, or between the second 90-degree hybrid and the polarization sharing antenna. 3rd and 4th amplitude phase control parts to change are provided, and a distribution part has the 2nd input terminal for the signal transmitted with the polarization orthogonal to the signal inputted into the 1st input terminal. And having a signal input to the second input terminal distributed to the two paths based on a set polarization angle, and receiving and outputting radio signals of two polarizations orthogonal to each other The calibration dual-polarized antenna having the first and second output terminals is opposed to the polarization plane control antenna, the calibration signal is input to the first input terminal, and the calibration is output from the first output terminal. The fourth scan is set so that the polarization angle is maximized. And a calibration signal is input to the first input terminal, the amount of phase change given by the third or fourth amplitude phase control unit is changed, and the calibration signal output from the second output terminal is minimized. A fifth step of setting the phase change amount of the third and fourth amplitude phase control units in the third and fourth amplitude phase control units and the calibration signal to the first input terminal A first sub-step for obtaining, as a first polarization angle, a polarization angle that minimizes the calibration signal output from the second output terminal in the range of 0 to π / 2, and a calibration signal A value obtained by subtracting π / 2 from the polarization angle that is input to the first input terminal and minimizes the calibration signal output from the first output terminal in the range of π / 2 to π is the second deviation. Based on the second sub-step obtained as the wave angle, and the average value of the first polarization angle and the second polarization angle, the third and fourth And a sixth step of repeating the third sub-step for setting the gain of the amplitude phase control unit until the difference between the first polarization angle and the second polarization angle falls within a predetermined threshold. preferable.

According to the polarization plane control antenna of the present invention,
Based on the set polarization angle, a distribution unit that distributes a signal input from the first input terminal to two paths, and a first 90-degree hybrid unit that converts the signal of each path distributed by the distribution unit And the second 90 degree hybrid means for reconverting the signals of the respective paths converted by the first 90 degree hybrid means and the signals of the respective paths output by the second 90 degree hybrid means are orthogonal to each other. The first and second amplitudes that are provided between the dual-polarized antenna that transmits by polarization and between the first 90-degree hybrid means and the second 90-degree hybrid means and change the amplitude and phase of the signal of each path A phase control means, a calibration signal extraction means for extracting a calibration signal input to the input terminal of the dual-polarized antenna, and a calibration signal extracted by the calibration extraction means Detection means for detecting and outputting a detection signal, voltage measurement means for measuring the voltage of the detection signal output from the detection means, monitoring the voltage measured by the voltage measurement means, and setting the polarization angle to the distribution means, And control means for setting the gain and phase change amount of the first and second amplitude phase control means.

According to another embodiment of the polarization control antenna of the present invention,
When the calibration signal is input to the first input terminal, the control means sets the polarization angle for inputting the calibration signal only to the input terminal to which the calibration signal extracting means of the polarization sharing antenna is not connected. The phase change amount is set in the distribution unit, the phase change amount of the first and second amplitude phase control means is changed, and the phase change amount when the voltage measured by the voltage measurement means is minimized is the first and second amplitude phase control. Then, the gain of the first and second amplitude phase control means is changed, and the gain when the voltage measured by the voltage measurement means is minimized is given to the first and second amplitude phase control means. It is also preferable to set.

In addition, according to another embodiment of the polarization control antenna of the present invention,
Based on the set polarization angle, a distribution unit that distributes a signal input from the first input terminal to two paths, and a third and a third that change the amplitude and phase of the signal of each path distributed by the distribution unit The polarization shared antenna that transmits the signals of the respective paths output by the fourth amplitude phase control means and the third and fourth amplitude phase control means with orthogonal polarizations, and a calibration signal are input. The amplitude and phase of the signal from one output terminal of the first 90-degree hybrid means and the first 90-degree hybrid means are changed, and the signal is output to the same path as the output of the third amplitude-phase control means The amplitude and phase of the signal from the other output terminal of the first amplitude / phase control means and the first 90-degree hybrid means are changed, and the signal is output to the same path as the output of the fourth amplitude / phase control means Second amplitude phase control A first 90-degree hybrid of the two 90-degree hybrid means and a second 90-degree hybrid means having the input terminal connected to each input terminal of the dual-polarized antenna and the second 90-degree hybrid means A calibration signal extraction means for extracting a calibration signal from the output signal of the output terminal connected to an output terminal on the side where the calibration signal input to the means is not output, and a calibration signal extracted by the calibration extraction means Detection means for detecting and outputting a detection signal, voltage measurement means for measuring the voltage of the detection signal output by the detection means, and monitoring the voltage measured by the voltage measurement means, the first, second, third and third And control means for setting the gain and phase change amount of the amplitude phase control means.

Furthermore, according to another embodiment of the polarization control antenna of the present invention,
When the calibration signal is input to the first 90-degree hybrid means, the control means changes the amount of phase change of the first and second amplitude phase control means, and the voltage measured by the voltage measuring means is minimized. Phase change amount is set in the first and second amplitude phase control means, and the set phase change amounts are stored as first and second phase calibration values, respectively. The gain when the voltage measured by the voltage measuring means is minimized is stored as the first and second amplitude calibration values, and the gain of the third amplitude phase controlling means is stored. The gain and phase change amount are changed based on the first amplitude calibration value and the first phase calibration value, respectively, and the gain and phase change amount of the fourth amplitude phase control means are changed to the second amplitude calibration value and the second amplitude calibration value. It is also preferable to change based on the phase calibration value.

  The calibration method according to the present invention is performed by monitoring a path through which a calibration signal does not flow in an ideal state and minimizing the calibration signal flowing through this path. However, the level of the calibration signal is monitored. Can be performed only with inexpensive devices such as a detector and a voltmeter. Further, these devices are very small, and the polarization plane control antenna according to the present invention incorporates these devices, and can be calibrated as necessary even during operation.

  The best mode for carrying out the present invention will be described in detail below with reference to the drawings.

  FIGS. 1 and 2 are views showing a configuration of a polarization plane control antenna which is an object of a calibration method according to the present invention. According to FIG. 1, the polarization plane control antenna includes a transmission signal control unit 100, a frequency conversion unit 5, amplification units 61 and 62, an output 90-degree hybrid 42, and a polarization sharing antenna 71. The signal control unit 100 includes a distribution unit 2, amplitude phase control units 31, 32, 33, and 34, and an input 90-degree hybrid 41, and 2 orthogonal to the two input terminals 11 and 12 of the distribution unit 2. A modulation signal carried by each of the two polarized waves is input. That is, for example, a signal to be transmitted with horizontal polarization is input to the input terminal 11, and a signal to be transmitted with vertical polarization is input to the input terminal 12. When only one polarization is used, the input terminal 12 can be omitted.

  The distribution unit 2 distributes and outputs the signal input to the input terminal 11 to two paths based on the polarization angle set in the distribution unit 2, and similarly sets the signal input to the input terminal 12. Based on the polarization angle, the signal is distributed to two paths and output. Here, the polarization angle is the inclination of the polarization plane of the polarization that transmits the modulation signal input to the input terminal 11 with respect to one of the two polarization planes that can be transmitted and received by the dual-polarized antenna 71. Is an angle. More specifically, when the input signals to the two input terminals 11 and 12 are (x, y), the output signals from the two output terminals are (u, v), and the polarization angle is θ, the distribution unit 2 is ,

となる様に信号の分配を行う。

The signal is distributed so that

  FIG. 3 is a functional block diagram of the distribution unit 2. The variable power distribution units 21 and 22 distribute the signals input to the input terminals 11 and 12 based on the set polarization angles and output the signals to the signal combining units 23 and 24, respectively. 24 synthesizes and outputs two input signals. FIG. 4 is a functional block diagram of the distribution unit 2 when only one input terminal is used. The variable power distribution unit 21 distributes and outputs a signal input to the input terminal 11 based on the polarization angle. To do.

  The amplitude and phase control units 31 and 32 are for calibration of the whole antenna, and change the amplitude and phase of a signal that passes based on the set gain coefficient and phase coefficient. The procedure for determining the gain coefficient and phase coefficient to be set will be described later.

  A configuration in which the frequency converter 5 for frequency conversion and the amplifiers 61 and 62 for signal amplification are sandwiched between the input 90-degree hybrid 41 and the output 90-degree hybrid 42 is described in Non-Patent Document 3. Similarly, for the purpose of balance operation between the paths of the respective components between the input 90-degree hybrid 41 and the output 90-degree hybrid 42, the input 90-degree hybrid 41 and the output 90-degree hybrid 42 are input 90 Amplitude phase control units 33 and 34 are provided at the output of the degree hybrid 41. The procedure for determining the gain coefficient and the phase coefficient set for the amplitude phase control units 33 and 34 will be described later.

In addition, when the input signal to the input terminal of the amplitude phase control units 31 to 34 is x, the output signal from the output terminal is u, the gain coefficient is α, and the phase coefficient is β,
u = xαe ^jβ (2)
When the input signals to the input terminals of the input 90-degree hybrid 41 and the output 90-degree hybrid 42 are (x, y) and the output signals from the output terminals are (u, v),

である。ここで、Ａ＝１／（√２）である。

It is. Here, A = 1 / (√2).

  The dual-polarized antenna 71 has two input terminals 13 and 14, one of which is connected to one output terminal of the output 90 degree hybrid 42 and the other connected to the other output terminal of the output 90 degree hybrid 42. The input signal of each terminal is transmitted as a radio signal with orthogonal polarization.

  The polarization plane control antenna shown in FIG. 2 eliminates the input 90-degree hybrid 41 and the output 90-degree hybrid 42 for balance operation in the configuration of FIG. 1 and the amplitude and phase control units 33 and 34 for calibration in this section. Is.

  In order to form a desired polarization plane, it is required to reduce the excitation error as much as possible. Therefore, the pass amplitude and phase of each path from each output of the distribution unit 2 to the two input terminals of the polarization sharing antenna 71 are required. Need to match. Hereinafter, the calibration method of the polarization plane control antenna will be described. First, the polarization control antenna including the configuration for the balance operation shown in FIG. 1 is calibrated (calibration 1) for the section to be balanced, and then the entire antenna (calibration 2) is calibrated. Do. On the other hand, only calibration 2 is performed for the polarization control antenna not including the configuration for the balance operation shown in FIG.

  FIG. 5 is a block diagram for the calibration 1 of the calibration method according to the present invention, in which the detector 8 for detecting the calibration signal is one input terminal of the polarization sharing antenna 71, and in FIG. 13 is connected to the output of the detector 8 for measuring the level of the detection signal from the detector 8. Hereinafter, the procedure of calibration 1 will be described.

  (Procedure 11) A signal for calibration is input to either the input terminal 11 or 12, and in an ideal state, the transmission signal control unit 100 prevents the signal from appearing at the terminal connected to the detector 8. The polarization angle of the distribution unit 2 is set. That is, the polarization angle θ in the equation (1) is set to 0 or π / 2. Further, the gain coefficient of the amplitude phase control units 31 to 34 is set to 1, and the phase coefficient is set to 0, that is, α = 1 and β = 0 in the equation (2).

  (Procedure 12) The phase coefficient of the amplitude phase control unit 33 or 34 is changed from 0 to 2π, and each phase coefficient when the output of the voltmeter 9 is minimized is set as a set value for the amplitude phase control units 33 and 34. At the same time, it is stored as a phase calibration coefficient.

  (Procedure 13) The output of the voltmeter 9 is monitored by changing the gain coefficient of the amplitude phase control unit 33 from 0 to 1 while keeping the gain coefficient of the amplitude phase control unit 34 at 1, and then the amplitude phase control unit 33 The gain coefficient of the amplitude phase control unit 34 is changed from 0 to 1 while the gain coefficient of the voltmeter 9 is kept at 1, and the output of the voltmeter 9 is monitored. The set values for the amplitude and phase control units 33 and 34 are stored as amplitude calibration coefficients.

  FIG. 6 is a diagram for explaining the calibration 1. As shown in FIG. 6A, by the initial setting in the procedure 11, the two signals 51 and 52 output from the transmission signal control unit 100 are equal in amplitude and have a phase difference of 90 degrees. Since the output 90-degree hybrid 42 outputs a signal synthesized by reducing the phase difference of each input signal to the input terminal by 90 degrees and a signal synthesized by increasing the phase difference by 90 degrees, as shown in FIG. If two signals orthogonal with equal amplitude are input to the output 90-degree hybrid 42 as they are, a signal is output from only one output terminal, and nothing is output from the other output terminal.

  However, due to the relative difference in amplitude characteristics and phase characteristics caused by the frequency converter 5, the amplifiers 61 and 62, and the wiring, the signals output from the amplifiers 61 and 62 are as shown in FIG. The amplitude is different and the phase difference is not 90 degrees. When the signal shown in FIG. 6B is input to the output 90-degree hybrid 42, as shown in FIG. 6C, a signal obtained by rotating the signal 52 to be canceled by 90 degrees is equal in amplitude to the signal 51. Since the signal does not become a reverse phase, the signal 53 remains. Procedures 12 and 13 adjust the gain and phase while monitoring this signal level.

  In the present invention, the amplitude phase control units 33 and 34 compensate for the relative difference between the amplitude characteristics and the phase characteristics of the two paths from the transmission signal control unit 100 to the input of the output 90-degree hybrid 42 by the above-described procedure. However, the devices used for the calibration are the detector 8 and the voltmeter 9, and these devices are much cheaper than a vector network analyzer or the like. FIG. 14 and FIG. 15 show detector outputs when the phase coefficient of the amplitude phase control units 33 and 34 is changed and when the gain coefficient is changed, respectively.

  Subsequently, calibration 2, that is, calibration of the entire antenna will be described. Even if there is a characteristic difference between the polarized waves of the dual-polarized antenna, that is, a gain difference and a phase difference, if this value is known, the gain phase difference and the phase difference are sent to the amplitude phase control units 31 and 32. Calibration is completed by setting a gain coefficient and a phase coefficient that compensate for. However, when the characteristics of the dual-polarized antenna are unknown, calibration is performed according to the following procedure by calibration 2 of the calibration method according to the present invention. FIG. 7 is a block diagram for calibration 2.

  According to FIG. 7, in order to calibrate the polarization plane control antenna, the dual polarization antenna 72 and the two detectors 8 and the voltmeter 9 for receiving the signals of each orthogonal polarization output from the dual polarization antenna 72 are provided. Use the correct calibration device. The polarization plane control antenna shown on the left side of FIG. 7 is the same as that shown in FIG. 1, but is an example, and is also used for calibration of the polarization plane control antenna shown in FIG. The calibration procedure will be described below.

  First, as a preliminary preparation, the polarization plane control antenna and the calibration device are opposed to each other, that is, arranged in the same direction. At this time, it is not necessary to match the polarization planes of the dual-polarization antenna 71 of the polarization plane control antenna and the dual-polarization antenna 72 of the calibration apparatus.

  (Procedure 21) Subsequently, a signal is input from one input terminal of the polarization plane control antenna, the polarization angle θ of the distribution unit 2 is changed from 0 to π / 2, and the output of the voltmeter 9 of the calibration device is On the other hand, the value of the polarization angle that is the maximum on the one hand and the minimum on the other hand is searched, and that value is set as a set value for the distribution unit 2.

  (Procedure 22) Subsequently, while monitoring the voltmeter 9 having the minimum output in the procedure 21, the phase coefficient of the amplitude phase control unit 31 or 32 is changed between 0 and 2π to monitor the voltmeter The phase coefficient at which the output of 9 is minimized is set in the amplitude phase control units 31 and 32, and this value is stored as a phase calibration coefficient. This completes the phase setting.

(Procedure 23) Subsequently, while inputting a signal from the same input terminal as in Procedure 21, the setting of the polarization angle of the distribution unit 2 was changed again from 0 to π / 2, and monitoring was performed in Procedures 21 and 22. The polarization angle value θ _{1 at} which the output of the voltmeter 9 is minimized is searched.

(Procedure 24) Subsequently, while inputting a signal from the same input terminal as in Procedure 21, the setting of the polarization angle of the distribution unit 2 was changed by π / 2 to π, and the output was minimized in Procedures 21 to 23. A value θ ₂ obtained by subtracting π / 2 from the polarization angle at which the output of the voltmeter 9 different from the voltmeter 9 is minimized is searched.

(Procedure 25) Subsequently, an average value θ ₃ of the polarization angle value θ ₁ and the polarization angle value θ ₂ is calculated, the polarization angle of the distribution unit 2 is set to θ ₃ , and the input terminal in the procedure 21 While the signal is input, the gain coefficient of the amplitude phase control unit 31 is changed to 1, the gain factor of the amplitude phase control unit 32 is changed from 0 to 1, and the gain coefficient of the amplitude phase control unit 32 is set to 1. The gain coefficient of the phase control unit 31 is changed from 0 to 1, and the gain coefficient of the amplitude phase control unit 31 and 32 that minimizes the output of the voltmeter 9 monitored in the procedure 21 is searched. The amplitude and phase control units 31 and 32 are set.

(Procedure 26) The procedure 23 to the procedure 25 are repeated, and the respective gain coefficients at the time when the difference between θ ₁ and θ ₂ becomes less than the threshold are set in the amplitude phase control units 31 and 32 and stored as amplitude calibration coefficients. To do.

In steps 23 to 25, two equations are obtained by using the deviation of the polarization angle and the relative value of the gain between the paths as variables, thereby obtaining the gain coefficient. The values of θ ₁ and θ ₂ are obtained. When the angle becomes 0 degree or 90 degrees, the equation cannot be solved. Therefore, in the first procedure 25, when the values of θ ₁ and θ ₂ become 0 degree or 90 degrees, the calibration device The polarization plane of the antenna is shifted, and calibration 2 is started again.

  FIG. 8 is a diagram for explaining the phase calibration in the procedures 21 and 22 described above. Since the polarization plane of the radio signal to be transmitted is changed by changing the polarization angle of the distribution means 2 (FIG. 8A), first, in step 21, the polarization plane of the radio signal transmitted by the polarization plane control antenna is changed. Then, the value of the polarization angle is adjusted so as to coincide with any polarization plane of the calibration device. At this time, if there is no phase difference between the two paths of the polarization plane control antenna, the voltage connected to the path on the side orthogonal to the polarization plane of the transmission signal of the polarization plane control antenna of the two paths of the calibration device The total 9 outputs are zero. However, when there is a phase difference between the two paths of the polarization control antenna, the radio signal transmitted by the polarization control antenna is elliptically polarized and its polarization direction rotates, so it does not coincide with the polarization plane. The output of the voltmeter 9 connected to the side path is not 0 (signal 55 in FIG. 8B). Therefore, in step 22, the phase is calibrated by adjusting the phase coefficient of the amplitude / phase control unit 31 or 32 while monitoring the voltmeter 9 connected to the path that does not coincide with the plane of polarization.

  FIG. 9 is a diagram for explaining the amplitude calibration in the procedures 23 to 26. As shown in FIG. 9A, when the amplitude characteristic is ideal, a signal obtained by combining two orthogonally polarized signals 56 and 57 transmitted by the polarization plane control antenna becomes a signal 58, which is Matches one of the polarization planes. However, when the amplitude characteristics are not the same and the amplitude gain on the signal 57 side is large as shown in FIG. 9B, for example, two orthogonally polarized signals 56 and 57 transmitted by the polarization plane control antenna are combined. The signal 58 does not coincide with one of the polarization planes of the calibration device, and the signal is observed in the other path.

The polarization angle value θ ₁ in the procedure 23 corresponds to obtaining the angle of one polarization plane of the calibration device of FIG. 9B and the signal 58, and this angle is the signal 56 or the signal 57 path. The direction differs depending on whether the gain is large. Further, the direction is different from θ _{2 obtained in the} procedure 24. Therefore, the gain coefficient is changed according to the average value of these angles, and the calibration ends when the values match.

  The polarization plane control antenna calibration method has been described above. However, the output 90-degree hybrid 42, the polarization shared antenna 71, and the like are analog devices and have a slight characteristic error. Therefore, in the calibration 1 and the calibration 2, the combination of the input terminal of the distribution unit 2 for inputting the calibration signal and the input terminal of the polarization sharing antenna 71 or the output terminal of the polarization sharing antenna 72 for monitoring the calibration signal is changed. Then, each calibration coefficient is measured, and the amplitude phase control units 31 to 34 are set to values obtained by averaging the calibration coefficients obtained by the respective measurements, thereby reducing the influence of the characteristic error of these devices. Can do.

  FIG. 10 is a block diagram of the polarization plane control antenna of the present invention. Elements that are the same as those already described are denoted by the same reference numerals and description thereof is omitted. 10 is the same as that of the transmission signal control unit 100 shown in FIG. 10, the calibration signal extraction unit 103 is connected to one of the two input terminals of the polarization sharing antenna 71, in FIG. 10, to the input terminal 13, and the calibration signal extraction unit 103 is connected. A calibration signal is extracted from the signal passing through the input terminal and output to the detector 8.

  The control unit 101 receives a calibration signal from the outside of the polarization plane control antenna. For example, when a calibration start command is received from the outside, the control unit 101 includes the distribution unit 2 of the transmission signal control unit 100 and the amplitude phase control units 31 to 34. Initial setting is performed, and then calibration processing is performed based on the output of the voltmeter 9. 12 is a flowchart of the calibration process in the polarization plane control antenna of FIG.

  (S101) The control unit 101 stores the polarization angle set in the distribution unit 2, and then inputs the calibration signal to the input terminal of the polarization sharing antenna 71 to which the calibration signal extraction unit 103 is not connected. That is, in FIG. 10, the setting of the polarization angle of the distribution unit 2 is changed so as to flow to the input terminal 14. That is, the polarization angle θ is set to 0 or π / 2 according to the relationship between the input terminal of the polarization sharing antenna 71 to which the calibration signal extraction unit 103 is connected and the input terminal to which the calibration signal is input. Set. Further, the gain coefficient and the phase coefficient set in the amplitude phase control units 31 and 32 are stored, and then the gain coefficient of the amplitude phase control units 31 to 34 is set to 1 and the phase coefficient is set to 0.

  (S102) The control unit 101 changes the phase coefficient of the amplitude phase control unit 33 or 34 between 0 and 2π, and sets the phase coefficient that minimizes the output of the voltmeter 9 in the amplitude phase control units 33 and 34.

  (S103) The control unit 101 monitors the output of the voltmeter 9 by changing the gain coefficient of the amplitude phase control unit 33 from 0 to 1 while keeping the gain coefficient of the amplitude phase control unit 34 at 1, and controls the amplitude phase control. The gain coefficient of the voltmeter 9 is monitored by changing the gain coefficient of the amplitude / phase control section 34 from 0 to 1 while the gain coefficient of the section 33 is 1, and the gain coefficient that minimizes the output of the voltmeter is set to the amplitude phase. Set in the control units 33 and 34. Thereafter, the polarization angle of the distribution unit 2 and the gain coefficient and phase coefficient of the amplitude phase control units 31 and 32 are returned to the stored values.

  With the above configuration, the amplitude and phase error of each path can be compensated even if the calibration state is lost due to a temperature change or the like during operation after the calibration according to the present invention described above. In the case of the polarization plane control antenna shown in FIGS. 1 and 10, the characteristic difference performed in calibration 2 does not need to be calibrated once the characteristics are known.

  In the case of the polarization plane control antenna of FIG. 2, the configuration shown in FIG. 11 can be used to compensate the amplitude and phase error of each path even if the calibration state is lost during operation. The polarization plane control antenna according to another embodiment of the present invention shown in FIG. 11 is the same as the polarization plane control antenna shown in FIG. 2 except that the control unit 101, the amplitude phase control units 33 and 34, the input 90-degree hybrid 41, and the output A 90-degree hybrid 42, a calibration signal extraction unit 103, a detector 8, a voltmeter 9, and a terminator 104 are added.

  In the configuration shown in FIG. 11, the configuration from the input 90-degree hybrid 41 to the output 90-degree hybrid 42 of the polarization plane control antenna of FIG. 1 is provided for calibration. The control unit 101 receives a calibration signal from the outside of the polarization control antenna. For example, when a calibration start command is received from the outside, the calibration signal input from the outside is input to one input of the 90-degree hybrid 41. The signal system is switched so as to lead to the terminal. Note that the output terminal of the output 90-degree hybrid 42 connected to the calibration signal extraction unit 103 is set to the side on which the calibration signal input to the input 90-degree hybrid 41 is not output. Further, the control unit 101 performs initial setting of the amplitude and phase control units 33 and 34, and then performs calibration processing based on the output of the voltmeter 9. FIG. 13 is a flowchart of the calibration process in the polarization plane control antenna of FIG.

  (S201) The control unit 101 sets the gain coefficient of the amplitude phase control units 33 and 34 to 1 and the phase coefficient to 0.

  (S202) The control unit 101 changes the phase coefficient of the amplitude phase control unit 33 or 34 from 0 to 2π, sets the phase coefficient that minimizes the output of the voltmeter 9 to the amplitude phase control units 33 and 34, The set value is stored as a phase calibration coefficient.

  (S203) The control unit 101 monitors the output of the voltmeter 9 by changing the gain coefficient of the amplitude phase control unit 33 from 0 to 1 while keeping the gain coefficient of the amplitude phase control unit 34 at 1, and controls the amplitude phase control. The gain coefficient of the voltmeter 9 is monitored by changing the gain coefficient of the amplitude phase control section 34 from 0 to 1 while the gain coefficient of the section 33 is 1, and the gain coefficient that minimizes the output of the voltmeter 9 is The values are set in the phase control units 33 and 34, and the set values are stored as gain calibration coefficients.

  (S204) The control unit 101 changes the setting of the amplitude phase control unit 31 based on the gain calibration coefficient and the phase calibration coefficient of the amplitude phase control unit 33, and the amplitude based on the gain calibration coefficient and the phase calibration coefficient of the amplitude phase control unit 34. The setting of the phase control unit 32 is changed. More specifically, a new gain coefficient and phase coefficient obtained by superimposing the gain coefficient and phase coefficient set in the amplitude phase control unit 33 on the current gain coefficient and phase coefficient of the amplitude phase control unit 31 are obtained, and this new gain is obtained. Coefficient and phase coefficient are set in the amplitude phase control unit 31, and the gain coefficient and phase coefficient set in the amplitude phase control unit 34 are superposed on the current gain coefficient and phase coefficient of the amplitude phase control unit 32, and a new gain coefficient and A phase coefficient is obtained, and the new gain coefficient and phase coefficient are set in the amplitude phase control unit 32.

  In the polarization plane control antenna shown in FIGS. 1 and 10, the amplitude phase control units 31 and 32 may be provided between the output hybrid 42 and the polarization sharing antenna 71.

  As described above, the calibration method according to the present invention enables calibration only with inexpensive devices such as a detector and a voltmeter. These devices are very small, and the polarization plane control antenna according to the present invention incorporates these devices and can be calibrated as necessary even during operation. Furthermore, by applying this calibration to a satellite-mounted antenna that is actually used, each polarization error of the satellite-mounted antenna can be detected.

It is a figure which shows the form of the polarization plane control antenna which is the object of the calibration method by this invention. It is a figure which shows the other form of the polarization plane control antenna which is the object of the calibration method by this invention. It is a functional block diagram of a distribution part. It is a functional block diagram of the other form of a distribution part. It is a block diagram for implementing the calibration 1 of the calibration method by this invention. It is a figure explaining the calibration 1. FIG. It is a block diagram for implementing the calibration 2 of the calibration method by this invention. It is a figure explaining the calibration of the phase in the calibration 2. FIG. It is a figure explaining the calibration of the amplitude in the calibration 2. FIG. It is a block diagram of the polarization plane control antenna by this invention. It is a block diagram of other embodiment of the polarization plane control antenna by this invention. It is a flowchart of the calibration method in the polarization plane control antenna shown in FIG. It is a flowchart of the calibration method in the polarization plane control antenna shown in FIG. It is a figure which shows a detector output when a phase coefficient is changed. It is a figure which shows a detector output when changing a gain coefficient. It is a block diagram of the calibration by a prior art.

Explanation of symbols

11, 12, 13, 14 Input terminal 2 Distribution unit 21, 22 Variable power distribution unit 23, 24 Signal synthesis unit 31, 32, 33, 34 Amplitude phase control unit 41 Input 90 degree hybrid 42 Output 90 degree hybrid 5 Frequency conversion unit 51, 52, 53, 56, 57, 58 Signal 61, 62 Amplifier 71, 72 Dual-polarized antenna 8 Detector 9 Voltmeter 100 Transmission signal controller 101 Controller 103 Calibration signal extractor 104 Terminator

Claims (7)

A distribution unit that distributes a signal input from the first input terminal to two paths based on the set polarization angle; and a first 90-degree hybrid that converts a signal of each path distributed by the distribution unit; The second 90-degree hybrid that reconverts the signal of each path converted by the first 90-degree hybrid and the signal of each path output by the second 90-degree hybrid are transmitted with orthogonal polarizations, respectively. And a first and second amplitude / phase control unit that are provided between the first 90-degree hybrid and the second 90-degree hybrid and change the amplitude and phase of the signal of each path. A polarization plane control antenna calibration method,
A polarization angle value for inputting a calibration signal input to the first input terminal only to one input terminal of the dual-polarized antenna is set in the distribution unit, and the first amplitude phase control unit and the second amplitude are set. A first step of setting the phase change amount and the gain in the phase control unit to be the same;
The calibration signal is input to the first input terminal, the amount of phase change given by the first or second amplitude phase control unit is changed, and the calibration signal input to the other input terminal of the polarization sharing antenna is minimized. A second step of setting the phase change amounts of the first and second amplitude phase control units at the time of becoming the first and second amplitude phase control units;
The calibration signal is input to the first input terminal, the gain of the first amplitude phase control unit is set to 1, the gain of the second amplitude phase control unit is changed from 0 to 1, and the second amplitude When the gain of the first amplitude phase control unit is changed from 0 to 1 while the gain of the phase control unit is 1, and the calibration signal input to the other input terminal of the dual-polarized antenna is minimized A third step of setting the gains of the first and second amplitude phase control units in the first and second amplitude phase control units;
Calibration method including: The distribution unit has a second input terminal for a signal to be transmitted with a polarization orthogonal to the signal input to the first input terminal, and the signal input to the second input terminal is set. Distributed to the two paths based on the polarization angle
After the execution of the first step to the third step, the calibration signal is input to the second input terminal, and the first step to the third step are executed again.
The average value of the gain and phase change amount of the first and second amplitude phase control units obtained in each execution is set in the first and second amplitude phase control units.
The method of claim 1. The polarization plane control antenna includes a third and a second that change the amplitude and phase of the signal of each path between the distributor and the first 90-degree hybrid, or between the second 90-degree hybrid and the polarization sharing antenna. 4 amplitude phase control units,
The distribution unit has a second input terminal for a signal to be transmitted with a polarization orthogonal to the signal input to the first input terminal, and the signal input to the second input terminal is set. Distributed to the two paths based on the polarization angle
A calibration polarization shared antenna having first and second output terminals for receiving and outputting radio signals of two polarized waves orthogonal to each other is opposed to the polarization plane control antenna,
A fourth step of inputting the calibration signal to the first input terminal and setting the polarization angle so that the calibration signal output from the first output terminal is maximized;
When the calibration signal is input to the first input terminal, the phase change amount given by the third or fourth amplitude phase control unit is changed, and the calibration signal output from the second output terminal is minimized A fifth step of setting the phase change amounts of the third and fourth amplitude phase control units in the third and fourth amplitude phase control units;
A calibration signal is input to the first input terminal, and the polarization angle that minimizes the calibration signal output from the second output terminal in the range of 0 to π / 2 is obtained as the first polarization angle. From the first substep, the calibration signal is input to the first input terminal, and the polarization angle that minimizes the calibration signal output from the first output terminal in the range of π / 2 to π is π / A second substep for obtaining a value obtained by subtracting 2 as the second polarization angle, and third and fourth amplitude phase control units based on the average value of the first polarization angle and the second polarization angle. A sixth step of repeating the third sub-step of setting the gain of the first until the difference between the first polarization angle and the second polarization angle is within a predetermined threshold;
The method of claim 1 comprising: Distribution means for distributing a signal input from the first input terminal to two paths based on the set polarization angle;
First 90 degree hybrid means for converting the signal of each path distributed by the distribution means;
Second 90 degree hybrid means for reconverting the signal of each path converted by the first 90 degree hybrid means;
A dual-polarized antenna that transmits signals of each path output by the second 90-degree hybrid means with orthogonal polarizations;
First and second amplitude phase control means provided between the first 90-degree hybrid means and the second 90-degree hybrid means to change the amplitude and phase of the signal of each path;
A calibration signal extracting means for connecting to any input terminal of the polarization sharing antenna and extracting a calibration signal input to the input terminal;
Detection means for detecting the calibration signal extracted by the calibration extraction means and outputting a detection signal;
Voltage measurement means for measuring the voltage of the detection signal output by the detection means;
Control means for monitoring the voltage measured by the voltage measurement means and setting the polarization angle set in the distribution means, and the gain and phase change amount of the first and second amplitude phase control means;
Polarized plane control antenna. When the calibration signal is input to the first input terminal, the control means sets the polarization angle for inputting the calibration signal only to the input terminal to which the calibration signal extracting means of the polarization sharing antenna is not connected. The phase change amount is set in the distribution unit, the phase change amount of the first and second amplitude phase control means is changed, and the phase change amount when the voltage measured by the voltage measurement means is minimized is the first and second amplitude phase control. Then, the gain of the first and second amplitude phase control means is changed, and the gain when the voltage measured by the voltage measurement means is minimized is given to the first and second amplitude phase control means. Set,
The polarization plane control antenna according to claim 4. Distribution means for distributing a signal input from the first input terminal to two paths based on the set polarization angle;
Third and fourth amplitude phase control means for changing the amplitude and phase of the signal of each path distributed by the distribution means;
A dual-polarized antenna that transmits the signals of the respective paths output by the third and fourth amplitude and phase control means with orthogonal polarizations;
First 90 degree hybrid means to which a calibration signal is input;
A first amplitude phase control means for changing the amplitude and phase of the signal from one output terminal of the first 90-degree hybrid means and outputting a signal in the same path as the output of the third amplitude phase control means;
A second amplitude and phase control means for changing the amplitude and phase of the signal from the other output terminal of the first 90-degree hybrid means and outputting a signal to the same path as the output of the fourth amplitude and phase control means;
A second 90-degree hybrid means having its input terminal connected to each input terminal of the dual-polarization antenna;
Of the two output terminals of the second 90-degree hybrid means, the calibration signal input to the first 90-degree hybrid means is connected to the output terminal on which the calibration signal is not output, and the calibration signal is derived from the output signal of the output terminal. Calibration signal extraction means for extracting
Detection means for detecting the calibration signal extracted by the calibration extraction means and outputting a detection signal;
Voltage measurement means for measuring the voltage of the detection signal output by the detection means;
Control means for monitoring the voltage measured by the voltage measuring means and setting the gain and phase change amount of the first, second, third and fourth amplitude phase control means;
Polarized plane control antenna. When the calibration signal is input to the first 90-degree hybrid means, the control means changes the amount of phase change of the first and second amplitude phase control means, and the voltage measured by the voltage measuring means is minimized. Phase change amount is set in the first and second amplitude phase control means, and the set phase change amounts are stored as first and second phase calibration values, respectively. The gain when the voltage measured by the voltage measuring means is minimized is stored as the first and second amplitude calibration values, and the gain of the third amplitude phase controlling means is stored. The gain and phase change amount are changed based on the first amplitude calibration value and the first phase calibration value, respectively, and the gain and phase change amount of the fourth amplitude phase control means are changed to the second amplitude calibration value and the second amplitude calibration value. Change based on the phase calibration value of
The polarization plane control antenna according to claim 6.

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