JP2609648B2 - High-precision radio sensor simulator - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device that simulates a function equivalent to that of a radio wave sensor that outputs a radio wave signal in accordance with the directional direction of an antenna.

[Conventional technology]

As a device for measuring the attitude of a satellite, that is, which direction the satellite structure is facing, a sun sensor (sun sensor) or star sensor that measures based on the positions of the sun and stars, and a measurement based on the position and width of the earth There is a radio sensor (RF sensor) that detects the attitude of a satellite based on the arrival direction of a radio wave transmitted from a target earth transmitting station or a target ground transmitting station.

References describing these examples of use include "Ichikawa Hiroshi," Special Issue on Experimental Communications and Broadcasting Satellites in Japan 3. Medium-sized Experimental Broadcasting Satellites (BS), "IEICE Journal, Vol. 82, No. 2, Electronic Communications Academic Conference February 1978 ”or“ G. Perrotta and D.
Fiore, “TV Broadcasting from Satellite: A Payload ′
s Designer View-point ", 32th Congress of Internati
onal Astronautical Federation, IFA'81, Rome, Italy, S
ept, 1981.].

The above-mentioned radio wave sensor detects the arrival direction of a radio wave by a monopulse tracking method. The monopulse tracking method is described in, for example, "Electronic Communication Handbook (Augmented and Revised Version)" by the IEICE Handbook Committee, Showa Era. As indicated in the May 20, 1980 supplementary and revised edition,
There are a plurality of primary radiators, that is, a method using an electromagnetic horn, and a method for detecting a higher-order mode.

In the method using a plurality of electromagnetic horns, for example, four primary radiators are arranged symmetrically, and beams are slightly offset from each other with respect to the central axis in the antenna direction. Configure the circuit. Further, for example, the power supply circuit is configured so that a difference between horn outputs arranged in east and west and a difference between horn outputs arranged in north and south are obtained.

The reference signal, which is the sum of the horns, has a maximum amplitude when the direction of the antenna coincides with the direction of arrival of the tracking signal, and has a substantially constant phase in the detectable angle range of the direction of the antenna.

The amplitude of the error signal, which is the difference between the horn outputs, is almost zero when the antenna directivity and the tracking signal arrival direction match, and the difference signal between the horn outputs arranged east and west is the antenna directivity and the tracking signal arrival direction. As the angle of deviation in the east-west direction increases, the amplitude increases and the direction of the antenna shifts to the east or west, centering on the angle at which the antenna direction and the tracking signal arrival direction coincide. The phase is inverted. Similarly, the signal of the difference between the horn outputs arranged in the north-south direction increases in amplitude as the angle of the shift in the north-south direction between the antenna pointing direction and the tracking signal arrival direction increases, and the antenna pointing direction and the tracking signal arrival direction. Around the angle at which
The phase is inverted depending on whether the direction of the antenna is shifted to the south or the north, depending on the direction of the shift.

That is, a monopulse signal pattern indicating the amplitude and phase of the error signal with respect to the directional angle of the antenna is represented as shown in FIGS.

FIG. 1 shows an example of the configuration of a radio wave sensor simulating device for obtaining these monopulse signals in a simulated manner.

In the figure, numeral 1 denotes an angle sensor, and 2 denotes a controller. The controller 2 generates drive signals for the variable attenuator and the variable phase shifter in accordance with the output of the angle sensor, and internally includes an output amplitude pattern as shown in FIG. A monopulse signal pattern such as an output phase pattern shown in FIG.

3 is an RF signal generator, 4 is a variable attenuator, 5 is a digital variable phase shifter, 6 is an output terminal, and 7 and 7 'are antennas.

The operation of the radio sensor simulator will be described below.
First, the angle sensor 1 reads the angle information and sends the angle information to the controller 2. Controller 2 that reads angle information
Calculates the insertion attenuation for the read angle based on the monopulse signal pattern stored in advance.

Next, the control voltages of the variable attenuator 4 and the digital variable phase shifter 5 to be controlled are calculated from the results and applied to each of them. The RF signal from the RF signal generator 3 is adjusted to a predetermined amplitude by the variable attenuator 4 and the digital variable phase shifter 5, and is adjusted to 0 ° or 180 ° in accordance with the sign of the angle signal.
The phase is set to ゜.

[Problems to be solved by the invention]

In the radio sensor simulating apparatus having the configuration as shown in FIG. 1, a variable attenuator using a PIN diode as a conventional variable attenuator is used. There was a problem of change.

FIG. 4 is a graph showing the change of the passing phase with the attenuation of the variable attenuator.

FIG. 4 shows an example of an attenuator in a frequency band of 30 GHz. According to this, it can be seen that a phase error of 50 ° is generated for an attenuation of 30 dB.

FIG. 5 is a diagram showing a state of a passing phase by a variable attenuator when a directivity angle θ of an angle sensor is changed,
Reference numeral 11 denotes a phase output with respect to the directivity angle θ.

As described above, since the conventional variable attenuator only digitally sets the variable attenuator to 0 ° or 180 °, there is a problem that the phase change of the variable attenuator cannot be corrected.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described conventional problems, and has as its object to provide a radio sensor simulating apparatus capable of correcting a phase change of a variable attenuator and outputting a high-precision monopulse signal. I have.

[Means for solving the problem]

According to the present invention, the above objects are achieved by the means as set forth in the claims.

That is, the present invention provides a high-frequency signal generator, a variable attenuator connected to the high-frequency signal generator and capable of adjusting the amplitude of the high-frequency signal generator output by an externally applied control signal, and an output of the variable attenuator. The input side is connected to the side, an analog variable phase shifter that adjusts and outputs the phase of the input signal by a control signal given from the outside, an angle sensor that detects the directional angle of the antenna, and an antenna that is a required characteristic Data indicating the relationship between the directional angle and the amplitude of the output signal, data indicating the relationship between the directional angle of the antenna and the phase of the output signal, the control voltage applied to the variable attenuator which is a characteristic unique to the element, and the variable attenuator Data indicating the relationship between the variable attenuator and the data indicating the relationship between the variable attenuator and the phase change amount of the variable attenuator generated along with the attenuation change of the variable attenuator. A memory for storing data indicating a relationship between a control voltage and a phase shift amount of the variable phase shifter; and an output of the angle sensor indicating a relationship between a directional angle of an antenna in the memory and an amplitude of an output signal. The amplitude of the output signal, which is regarded as a required value, is considered as the directivity angle in the data, and the change from 0 dB of the amplitude of the output signal is the attenuation of the variable attenuator. This attenuation is referred to as the variable attenuator in the memory. To generate a control voltage obtained by applying the relationship between the control voltage to be applied to the variable attenuator and the attenuation amount of the variable attenuator, and to output the output of the angle sensor to the relationship between the directional angle in the memory and the phase of the output signal. The phase of the output signal as a required value obtained by considering the directivity angle in the data indicating
A phase change amount obtained by applying the amount of attenuation given to the variable attenuator to data indicating a relationship with the amount of phase change of the variable attenuator generated accompanying the change in the amount of attenuation of the variable attenuator in the memory. Is the phase shift amount to be realized by the variable phase shifter. The control voltage applied to the variable phase shifter in the memory and the phase shift amount of the variable phase shifter And a control unit for generating a control voltage obtained by applying the data to the data indicating the relationship between the variable attenuator and the analog variable phase shifter to control the amplitude and phase of the output signal of the high-frequency signal generator. A high-precision radio wave characterized by outputting a signal corresponding to an error signal in a radio wave sensor using a monopulse tracking method, the signal being set to an amplitude and a phase corresponding to an antenna directivity angle. Sensor imitation It is.

The high-precision radio wave sensor simulator of the present invention uses an analog variable phase shifter as a variable phase shifter, and can compensate for a phase error caused by control of a variable attenuator. It is different from the simulator.

〔Example〕

FIG. 6 shows the first embodiment of the present invention, and is a configuration diagram of a high-precision radio sensor simulating apparatus.

In FIG. 1, reference numeral 1 denotes an angle sensor, and 2 denotes a controller. The controller 2 has a function of generating a drive signal for a variable attenuator and a variable phase shifter in accordance with the output of the angle sensor. A desired monopulse as shown in FIG. 2 and FIG. While storing the signal pattern,
The characteristic data of the variable attenuator as shown in the figure and the characteristic data of the analog variable phase shifter as shown in FIG. 7 are also stored.
3 is an RF signal generator, 4 is a variable attenuator, 6 is an output terminal, 7 and 7 'are antennas, and 12 is an analog variable phase shifter.

The operation will be described with reference to the figure. First, the angle sensor 1 reads angle information and sends the angle information to the controller 2. The controller 2 that has read the angle information calculates the insertion attenuation amount for the read angle based on the monopulse signal pattern stored in advance. At the same time, the phase delay accompanying the insertion attenuation is determined from the data in FIG.

Thus, the controller 2 applies a control voltage to the variable attenuator 4 and applies a phase of 0 ° or 180 ° corresponding to the positive or negative of the angle signal and a phase corresponding to the amount of attenuation to the analog variable phase shifter 12. A control voltage is generated in the analog phase shifter 12 so as to provide compensation. Here, if the analog variable phase shifter 12 is a motor-driven (mechanical drive) type analog phase shifter, there is no problem of hysteresis, so that it can be uniquely compensated.

On the other hand, if the analog variable phase shifter 12 uses ferrite, it has a hysteresis characteristic 13 as shown in FIG. Therefore, the phase difference between the going and returning of the hysteresis affects the signal as a phase error. If the insertion attenuation is about 50 dB, the control range of the variable phase shifter is 28
0 ° is sufficient, and at this time, the seventh
By using the intermediate value 14 of the hysteresis characteristic shown in the figure, the influence of the hysteresis characteristic can be reduced.

FIG. 8 shows how the second phase shifter 12 controlled in an analog manner compensates for the phase delay as described above. In the figure, reference numeral 15 denotes a phase output with respect to the directivity angle θ.

FIG. 9 is a block diagram of a second embodiment of the present invention, which further enhances the phase compensation accuracy. In order to reduce the influence of the hysteresis characteristic of the analog variable phase shifter 12, the phase of 0 ° or 180 ° is handled by the digital variable phase shifter 5, and the analog variable phase shifter 12 has only the phase delay of the variable attenuator. Is controlled to compensate for

1 is an angle sensor, 2 is a controller for generating a drive signal for a variable attenuator and a variable phase shifter with respect to the output of the angle sensor, and outputs a desired monopulse signal pattern shown in FIG. 2 and FIG. In addition to the storage, the characteristic data of the variable attenuator shown in FIG. 4 and the analog variable phase shifter shown in FIG. 10 are also stored.

3 is an RF signal generator, 4 is a variable attenuator, 5 is a digital variable phase shifter, 6 is an output terminal, 7 and 7 'are antennas, and 12 is an analog variable phase shifter.

The operation will be described with reference to the figure. First, an angle sensor reads angle information and sends the angle information to a control unit. The control unit that has read the angle information calculates the insertion attenuation amount for the read angle based on the monopulse signal pattern stored in advance. At the same time, the phase delay accompanying the insertion attenuation is determined from the data in FIG.

The control unit applies the control voltage to the variable attenuator, and at the same time, controls the digital variable phase shifter 5 in accordance with the sign of the angle signal.
Is set to 0 ° or 180 °, and the analog variable phase shifter is set to compensate for the phase delay corresponding to the amount of attenuation.

Here, if the analog variable phase shifter 12 is a variable phase shifter using ferrite, it has a hysteresis characteristic, but if the insertion attenuation is about 50 dB, the phase control range becomes
About 100 mm is enough. At this time, the hysteresis is 10th.
As shown in FIG. 16 (17 in FIG. 17 indicates an intermediate value of the hysteresis characteristic), the difference between the forward and backward directions is much smaller than that shown in FIG.

Therefore, the influence of the hysteresis characteristic can be further reduced.

〔The invention's effect〕

As described above, the present invention can reduce the occurrence of a phase error in a device that outputs a monopulse signal equivalent to a radio wave sensor based on information from an angle sensor without flying a radio wave into space, Tracking receiver, antenna drive control circuit connected after the radio wave sensor pseudo device,
There is an advantage that the phase error is not affected on the antenna driving mechanism.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of the configuration of a conventional radio wave sensor pseudo device, FIG. 2 is an output amplitude pattern of the radio wave sensor pseudo device,
FIG. 3 shows an output phase pattern of the radio wave sensor simulation device, FIG.
FIG. 5 is a diagram showing the characteristics of the attenuation amount and the passing phase of the variable attenuator, FIG. 5 is a diagram showing the phase output of the radio wave sensor simulator, FIG. 6 is a diagram showing the configuration of the first and embodiment of the present invention, FIG. 7 is a diagram showing characteristics of the analog variable phase shifter, and FIG.
FIG. 9 is a diagram showing a configuration of a second embodiment of the present invention, and FIG. 10 is a diagram showing characteristics of an analog variable phase shifter. 1 ... Angle sensor, 2 ... Controller, 3 ... RF signal generator, 4 ... Variable attenuator, 5 ... Digital variable phase shifter,
6 ... output terminal, 7, 7 '... antenna, 8 ... monopulse signal pattern, 9 ... digital output phase pattern,
10: Curve of attenuation and passing phase of variable attenuator, 11:
Phase output, 12: Analog variable phase shifter, 13: Phase characteristic of analog variable phase shifter, 14: Intermediate value of phase characteristic of analog variable phase shifter, 15: Phase output with phase compensation, 16 …
… Phase characteristics of analog variable phase shifter, 17… Intermediate value of phase characteristics of analog variable phase shifter.

Claims (1)

(57) [Claims] 1. A high-frequency signal generator, a variable attenuator connected to the high-frequency signal generator and capable of adjusting the amplitude of the high-frequency signal generator output by an externally applied control signal, and an output side of the variable attenuator An analog variable phase shifter that adjusts the phase of the input signal according to a control signal supplied from the outside and outputs the signal, an angle sensor that detects the directivity angle of the antenna, and the directivity of the antenna that is the required characteristic Data indicating the relationship between the angle and the amplitude of the output signal, data indicating the relationship between the directional angle of the antenna and the phase of the output signal, control voltage applied to the variable attenuator, which is an element-specific characteristic, and the variable attenuator Data indicating the relationship with the amount of attenuation, data indicating the relationship with the amount of phase change of the variable attenuator that accompanies the change in attenuation of the variable attenuator, and a control signal supplied to the variable phase shifter. A memory for storing data indicating a relationship between a pressure and a phase shift amount of the variable phase shifter; and an output of the angle sensor, and data indicating a relationship between a directivity angle of an antenna and an amplitude of an output signal in the memory. The amplitude of the output signal, which is regarded as the required angle, is obtained as the directivity angle, and the change from 0 dB of the amplitude of the output signal is the attenuation of the variable attenuator, and this attenuation is stored in the variable attenuator in the memory. While generating a control voltage obtained by applying the control voltage to be applied to the data indicating the relationship between the variable attenuator and the amount of attenuation, the output of the angle sensor is used to determine the relationship between the directional angle in the memory and the phase of the output signal. The phase of the output signal, which is a required value obtained as a directivity angle in the data shown, and the amount of attenuation given to the variable attenuator, which is generated in association with the variation of the attenuation of the variable attenuator in the memory. The inverse sign of the difference from the phase change obtained by applying the data to the relationship with the phase change of the attenuator is the phase shift to be realized by the variable phase shifter. A control unit configured to generate a control voltage obtained by applying data indicating a relationship between a control voltage applied to a variable phase shifter in a memory and a phase shift amount of the variable phase shifter; By controlling the amplitude and phase of the output signal of the high-frequency signal generator by a variable phase shifter, a signal corresponding to an error signal in a radio sensor using a monopulse tracking method, and an amplitude corresponding to an antenna directional angle. A high-precision radio sensor simulating device, which outputs a signal set to a phase and a simulated signal.