JPH09261149A - Directing controller for communication antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the antenna directing accuracy and to attain the recovery of communication by correcting the antenna directing command value by means of an earth sensor and the attitude error correction value outputted from an attitude error correction value calculation part against the temporary down of a communication circuit. SOLUTION: In order to compensate the error factor of the antenna directing accuracy, an earth sensor 23 detects the relative attitude of a spacecraft to the earth and outputs a roll/pitch biaxial attitude error signal 24 that serves as a dominant factor of an antenna directing error. An attitude error correction value calculation part 27 calculates the antenna attitude error correction value 25. Then an adder 26 adds together the value 25, the directing command value 19 and the bias error estimation value 29. Thus an after-correction directing command 22 is generated, and the antenna drive control is carried out via a switch 13. In such a constitution, it is possible to compensate the attitude error, to track and direct the spacecraft of the opposite side with high accuracy that is equivalent to that set in a mode 2 and also to attain the sure recovery of communication.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna mounted on a spacecraft that requires high-speed data communication, such as an earth observation machine and a robot experiment machine, and used for communication between the spacecrafts. The present invention relates to an antenna pointing control device that controls the pointing of the antenna.

[0002]

2. Description of the Related Art First, communication between spacecraft using the above antenna will be described with reference to FIG. In FIG. 5, 1
Reference characters a and 1b are spacecraft that travel in different orbits of outer space, and they are equipped with antennas 2a and 2b for performing mutual data communication. Antennas 2a, 2
b has a very large shape due to a large transmission distance and the like, and further has a characteristic that the beam width is narrow and the directivity is strong. In order to continuously perform data communication between spacecraft that relatively move at high speed, an antenna control device 3 for interspacecraft communication that tracks and directs the antenna with high accuracy is attached to the antenna. Inside the antenna control device 3, a tracking sensor 4 for detecting the arrival direction of a communication beam, an antenna support boom 5 fixed to the spacecraft body, and an antenna drive mechanism mounted between the antennas to drive the antenna. 6 and the antenna drive mechanism 6
And an antenna control electronic circuit 8 for issuing an antenna drive command to the antenna drive mechanism 6.

FIG. 6 is a block diagram showing an example of a conventional antenna pointing control apparatus for inter-spacecraft communication. 2 in the figure
Is an antenna for data communication, and 4 is a communication beam for receiving a reception status 14 and a tracking error signal 1.
5 is a tracking sensor, 6 is an antenna drive mechanism that moves the antenna 2a according to the antenna drive signal 20, 7 is an angle sensor that outputs a rotation angle signal 16, 8 is an antenna control electronic circuit, and 9 is an antenna from the tracking error signal 15 described above. The error signal processing unit for calculating the pointing direction command value 17 of 10 is the orbit propagation unit for predicting the orbital positions of the two spacecraft and outputting the orbital data 18, and 11 is the relative angle of the other spacecraft from the orbital data 18. A relative angle calculation unit that performs calculation to calculate the pointing direction command value 19 of the antenna, 28 is a bias error model calculation unit that calculates a bias error estimated value 29 from the trajectory data 18, and 26 is a bias error estimation for the pointing direction command value 19. Value 2
An adder for adding 9 to output the corrected pointing direction command value 22, and a reference numeral 12 for the pointing direction command value 20 and the rotation angle signal 16 selected by the switch 13 based on the reception status 14.
It is a servo control unit that inputs and and outputs the antenna drive signal 21.

Next, the operation will be described. First, the operation of the pointing control of the antenna for spacecraft communication will be described. The basic operation of antenna pointing control is managed by the antenna control electronic circuit 8, and two types of operation modes are selectively used according to the communication state. (1) Mode 1 In the antenna control electronic circuit 8, the relative azimuth is calculated from the orbital position predictions of the two spacecrafts, and the antenna is driven so that the output of the angle sensor 7 matches this relative azimuth. This mode is used when data communication has not been established, such as during initial acquisition. (2) Mode 2 Based on the tracking error signal from the tracking sensor 4, the antenna is driven so that the tracking error becomes zero. This mode is used in situations where data communication is established during antenna tracking.

Next, the operation will be specifically described with reference to FIG. When the mode 2 in which the data communication is established is used, the tracking sensor 4 receives the communication beam from the other spacecraft, detects the tracking error from the radio field intensity distribution, and detects the tracking error signal 15
Is output. The error signal processing unit 9 uses the tracking error signal 1
5, the pointing direction command value 17 for two rotation axes of the antenna drive mechanism called azimuth / elevation is generated. The switch 13 is a switch for switching the input signal according to the operation mode, and selects the pointing direction command value 17 when the reception status 15 from the tracking sensor 4 is in the data communication state, that is, when the mode 2 is used. The servo control unit 12 receives the pointing direction command value 20 selected by the switch 13, and outputs the antenna driving signal 21 so that the azimuth / elevation axis of the antenna driving mechanism 6 matches the pointing direction command value 20. Take control. When mode 2 is used, antenna tracking / directivity control is performed in this way, enabling continuous data communication. On the other hand, when using the mode 1 in which the data communication is not established, the tracking error signal 15 from the tracking sensor 4 is not obtained, and the pointing direction command value of the antenna is generated by a method different from the mode 2. The orbit propagation unit 10 performs orbit propagation calculation based on the preset initial orbit information of the two spacecraft, calculates the current predicted position of the spacecraft, and outputs the orbit data 18.

The relative angle calculation unit 11 uses the trajectory data 18
Then, the relative azimuth angle of the spacecraft on the other side is calculated, and the pointing direction command value 19 for the azimuth / elevation axis of the antenna drive mechanism 6 is output. Bias error model calculator 2
Reference numeral 8 estimates a bias error caused by an attachment alignment error of the antenna 2a, the antenna support boom 5 and the like, a thermal deformation error, etc. based on the bias error model and inputs the track data 18 as an input, and outputs a bias error estimated value 29. When the mode 13 is used in the switch 13, the pointing direction command value 19
The corrected pointing direction command value 22 obtained by adding the bias error estimated value 29 to is selected. The servo control unit 12 receives the selected pointing direction command value 20, and receives the antenna drive mechanism 6
The rotation angle signal 16 output from the angle sensor 7 attached to the azimuth / elevation shaft of
The antenna drive signal 21 is output so as to match with, and the antenna is controlled. Although the antenna tracking / directivity control is performed in this manner when mode 1 is used, the antenna directivity accuracy is inferior to that in mode 2. Factors that deteriorate the antenna pointing accuracy include a bias error caused by an attachment alignment error of the antenna 2a and the antenna support boom 5, a thermal deformation error, and the like, and an attitude error of the spacecraft 1a.

The bias error is estimated and compensated by the bias error model calculator 28 when the mode 1 is used, and is detected and compensated by the tracking sensor 4 when the mode 2 is used. On the other hand, when there is an attitude error of the spacecraft 1a, it is possible to detect and compensate for this attitude error by the tracking sensor 4 when using the mode 2, while this attitude error is used as an antenna pointing error when using the mode 1. To remain. Therefore, mode 2 is basically used during the steady operation of performing data communication. However, if the communication line goes down due to a sudden change in the attitude change of the spacecraft or an instantaneous abnormality of the communication device, the mode 1 is entered, and the mode 1 is continued until the communication line is restored.

[0008]

Since the conventional antenna pointing control device for inter-spacecraft communication is constructed as described above, when the spacecraft attitude error is large, the communication line is temporarily suspended during steady operation. When it went down, there was a problem that the antenna could not be correctly directed toward the spacecraft of the other party, and in the worst case, radio waves could not be re-received and communication could not be restored.

The present invention has been made in order to solve the above-mentioned problems, and reliably realizes communication recovery even when the above attitude error exists when the communication line is temporarily down during steady operation. An object is to obtain a pointing control device for a communication antenna that can be used.

[0010]

A directional control device for a communication antenna according to the present invention is provided with an earth sensor and an attitude error correction value calculating section, so that the attitude can be maintained when the communication line is temporarily down. A means for performing antenna drive control by correcting the pointing direction command value by using the attitude error correction value output from the error correction value calculation unit is provided.

Further, the pointing control apparatus for the communication antenna according to the present invention is provided with the RF sensor and the attitude error correction value calculation unit, so that the attitude error correction value calculation is performed when the communication line is temporarily down. Correction is applied to the pointing direction command value using the attitude error correction value output from the
A means for performing antenna drive control is provided.

The directional control device for a communication antenna according to the present invention comprises the inertial sensor and the attitude error correction value calculating section, so that the attitude error correction value calculating section can be operated by the attitude error correction value calculating section when the communication line is temporarily down. A means for performing antenna drive control by correcting the pointing direction command value using the output attitude error correction value is provided.

Further, the antenna pointing control device for inter-spacecraft communication according to the present invention comprises the ground station pointing antenna tracking section and the attitude error correction value calculating section, so that when the communication line is temporarily down, The attitude error correction value output from the attitude error correction value calculation unit is used to correct the pointing direction command value, and means for performing antenna drive control is provided.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1. Embodiment 1 of the present invention will be described below with reference to the drawings. In FIG. 1, 23 is an earth sensor that detects the relative attitude of the spacecraft to the earth and outputs a biaxial attitude error signal 24 called roll / pitch angle, and 27 is an attitude error correction value 25 based on the attitude error signal. The attitude error correction value calculation unit 26 is an adder that adds the bias estimation value 29 and the attitude error correction value 25 to the pointing direction command value 19 and outputs the corrected pointing direction command value 22.

The operation of the antenna pointing control device for inter-spacecraft communication configured as described above will be described with reference to FIG. The attitude error of the spacecraft becomes an error factor that deteriorates the antenna pointing accuracy when using the mode 1. In order to compensate for this error factor, the earth sensor 23 and the attitude error correction value calculation unit 27 are provided. The earth sensor 23 detects the relative attitude of the spacecraft with respect to the earth, and outputs a roll / pitch biaxial attitude error signal 24 which is a dominant element of the antenna pointing error. The attitude error correction value calculation unit 27 calculates an attitude error correction value 25 converted from the attitude error signal 24 into the azimuth / elevation rotation axis of the antenna drive mechanism 6 based on the following equation (1).

[0016]

[Equation 1]

However, φ: Attitude error signal roll angle θ: Attitude error signal pitch angle δφ AZ: Attitude error correction value azimuth angle δφ EL: Attitude error correction value elevation angle Further, the attitude error correction value 25 and the pointing direction command in the adder 26. The value 19 and the bias error estimated value 29 are added,
The corrected pointing direction command value 22 is generated. When the communication mode temporarily goes down and the operation mode shifts to the mode 1, the switch 13 selects the corrected pointing direction command value 22 and the antenna drive control is performed based on this. In this way, by compensating for the attitude error, which is a problem even in mode 1, it is possible to track / orient the spacecraft on the other side as accurately as when using mode 2, and a reliable communication recovery can be realized.

Embodiment 2. In the first embodiment described above, the earth sensor 23 and the attitude error correction value calculation unit 27 are provided to compensate for the attitude control error of the spacecraft.
Even if the RF sensor 28 is provided, the same effect as that of the first embodiment can be achieved. FIG. 2 is a block diagram of an antenna pointing control apparatus for inter-spacecraft communication embodying the present invention. 2a, 4, in the figure
6 to 22 and 25 to 27 are the same as in FIG. Reference numeral 30 is an RF sensor that detects the relative attitude of the spacecraft with respect to the earth and outputs a biaxial attitude error signal 24 called azimuth / elevation angle, which is a dominant element of the antenna pointing error. Attitude error signal 24 detected by the RF sensor 28
Based on the above, the attitude error correction value calculation unit 27 calculates the attitude error correction value 25 according to the following equation (2).

[0019]

[Equation 2]

Where AZ: Attitude error signal azimuth angle ΥEL: Attitude error signal elevation angle δφAZ: Attitude error correction value azimuth angle δφEL: Attitude error correction value elevation angle In the adder 26, the pointing direction command value is obtained by this correction value. By correcting 19 and generating the corrected pointing direction command value 22, the same effect as in the first embodiment can be achieved.

Embodiment 3 Further, as shown in FIG. 3, even if the inertial sensor 31 is provided to compensate the attitude error of the spacecraft, the same effect as that of the first embodiment can be achieved. 2 in the figure
a, 4, 6 to 22, and 25 to 27 are the same as in FIG. 3
An inertial sensor 1 detects the attitude rate of the spacecraft with respect to the inertial space, and outputs the attitude error signal 24 of three roll / pitch / yaw axes, which is the dominant element of the antenna pointing error by integrating this rate. Is. Inertial sensor 31
The attitude error correction value calculating unit 27 calculates the attitude error correction value 25 based on the attitude error signal 24 detected by the following equation (3).

[0022]

(Equation 3)

However, φ: attitude error signal roll angle θ: attitude error signal pitch angle ψ: attitude error signal yaw angle φAZ: antenna drive angle azimuth angle φEL: antenna drive angle elevation angle δφAZ: attitude error correction value azimuth angle δφEL Attitude error correction value elevation angle By adding the correction value, the pointing direction command value 19 is corrected by the adder 26, and the corrected pointing direction command value 22 is generated, so that the same effect as the first embodiment can be achieved.

Embodiment 4 Further, as shown in FIG. 4, even if the ground station directional antenna tracking unit 32 is provided in order to compensate the attitude error of the spacecraft, the same effect as that of the first embodiment can be achieved. In the figure, 2a, 4, 6 to 22, and 25 to 27 are the same as in FIG. Reference numeral 32 denotes a ground station directional antenna tracking unit which is attached to the spacecraft and controls the direction of the antenna for performing data communication with the earth ground station. The ground station directional antenna tracking unit 32 detects the relative attitude with respect to the earth from the antenna driving angle obtained in the ground station antenna tracking, and becomes a dominant element of the antenna pointing error, which is a biaxial attitude error called azimuth / elevation angle. The signal 24 is output. The attitude error correction value calculation unit 27 calculates the attitude error correction value 25 according to the following equation (1) based on the attitude error signal 24 detected by the ground station directional antenna tracking unit 32. Adder 26
By correcting the pointing direction command value 19 with this correction value and generating the corrected pointing direction command value 22, the same effect as that of the first embodiment can be achieved.

[0025]

As described above, according to the present invention, when the communication line is temporarily down, the attitude error correction value output from the earth sensor and the attitude error correction value calculation unit is used to direct the antenna pointing direction. Since the correction is applied to the command value, it is possible to obtain the device in which the pointing accuracy of the antenna is high and the communication recovery can be surely realized.

According to the present invention, when the communication line is temporarily down, the antenna directional command is issued using the attitude error correction values output from the RF sensor, the attitude error correction value calculation unit and the attitude error model calculation unit. Since the correction is applied to the value, it is possible to obtain the device in which the pointing accuracy of the antenna is high and the communication recovery can be surely realized.

Further, according to the present invention, when the communication line is temporarily down, the attitude error correction value output from the inertial sensor and the attitude error correction value calculation unit is used to correct the pointing direction command value of the antenna. Since the configuration is such that the antenna is added, it is possible to obtain a device in which the pointing accuracy of the antenna is high and the communication recovery can be surely realized.

According to the present invention, when the communication line is temporarily down, the attitude error correction value output from the ground station directional antenna tracking unit and the attitude error correction value calculation unit is used to determine the pointing direction command value of the antenna. Since the correction is applied to the antenna, it is possible to obtain a device with high antenna pointing accuracy and reliable communication recovery.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an antenna pointing control device for inter-spacecraft communication according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of an antenna pointing control device for inter-spacecraft communication according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram of an antenna pointing control device for inter-spacecraft communication according to a third embodiment of the present invention.

FIG. 4 is a configuration diagram of an antenna pointing control device for inter-spacecraft communication according to a fourth embodiment of the present invention.

FIG. 5 is a conceptual diagram of communication between spacecraft using an antenna for communication between spacecrafts.

FIG. 6 is a block diagram of a conventional antenna pointing control device for inter-spacecraft communication.

[Explanation of symbols]

1 spacecraft, 2 antennas, 3 inter-spacecraft communication antenna pointing control device, 4 tracking sensor, 5 antenna support boom, 6 antenna drive mechanism, 7 angle sensor, 8 antenna control electronic circuit, 9 error signal processing unit, 10 Orbit propagation unit, 11 relative azimuth calculation unit, 12 servo control unit,
13 switches, 14 reception status, 15 tracking error signal, 16 rotation angle signal, 17 pointing direction command value, 1
8 orbit data, 19 pointing direction command value, 20 pointing direction command value, 21 antenna drive signal, 22 corrected pointing direction command value, 23 earth sensor, 24 attitude error signal, 2
5 attitude error correction value, 26 adder, 27 attitude error correction value calculation unit, 28 bias error model calculation unit, 29 bias error estimated value, 30 RF sensor, 31 inertial sensor, 32 ground station directional antenna tracking unit.

Claims (4)

[Claims] 1. A pointing sensor for an antenna, which is mounted on a spacecraft and performs communication between the spacecraft, and a tracking sensor for detecting a tracking error with a partner spacecraft, and an angle for detecting a driving angle of the antenna. A sensor, an antenna drive mechanism,
The earth sensor that detects the attitude error of the spacecraft with respect to the earth, the attitude error correction value calculation unit that calculates the attitude error correction value based on the above attitude error, and the orbital positions of the two spacecraft that communicate with each other. An orbit propagation unit that outputs data, a relative angle calculation unit that calculates the relative angle between the other spacecraft from the orbit data, and calculates the pointing direction command value for the antenna, and a bias error estimated value from the orbit data Bias error model calculation unit, an error signal processing unit that calculates the pointing direction command value of the antenna from the tracking error signal from the tracking sensor, the output of the relative angle calculation unit, the attitude error correction value and the bias error estimated value An adder that adds to generate an antenna pointing direction command value; a switch that selects the output of the adder or the output of the error signal processing unit according to the communication status of the antenna; Inputs the output of the directional direction command value and the angle sensor of the selected antenna switch, pointing control device of the communication antenna, characterized in that a servo controller for controlling the antenna drive mechanism. 2. A pointing sensor for an antenna, which is mounted on a spacecraft and performs communication between the spacecraft, and a tracking sensor for detecting a tracking error with the other spacecraft, and an angle for detecting a driving angle of the antenna. A sensor, an antenna drive mechanism,
An RF sensor that detects an attitude error of the spacecraft with respect to the earth, an attitude error correction value calculation unit that calculates an attitude error correction value based on the attitude error, and an orbital position of two spacecrafts that communicate with each other. An orbit propagation unit that outputs data, a relative angle calculation unit that calculates the relative angle between the other spacecraft from the orbit data, and calculates the pointing direction command value for the antenna, and a bias error estimated value from the orbit data Bias error model calculation unit, an error signal processing unit that calculates the pointing direction command value of the antenna from the tracking error signal from the tracking sensor, the output of the relative angle calculation unit, the attitude error correction value and the bias error estimated value An adder that adds to generate an antenna pointing direction command value; a switch that selects the output of the adder or the output of the error signal processing unit according to the communication status of the antenna; Inputs the output of the directional direction command value and the angle sensor of the selected antenna switch, pointing control device of the communication antenna, characterized in that a servo controller for controlling the antenna drive mechanism. 3. A pointing sensor for an antenna mounted on a spacecraft for communicating between spacecrafts, and a tracking sensor for detecting a tracking error with a partner spacecraft, and an angle for detecting a driving angle of the antenna. A sensor, an antenna drive mechanism,
An inertial sensor that detects an attitude error with respect to the inertial space of the spacecraft, an attitude error correction value calculation unit that calculates an attitude error correction value based on the attitude error, and predicts the orbital positions of the two spacecraft that communicate, An orbit propagation unit that outputs orbit data, a relative angle calculation unit that calculates the relative angle between the other spacecraft from the orbit data, and calculates the pointing direction command value of the antenna, and a bias error estimated value from the orbit data. Bias error model calculation unit for calculating, error signal processing unit for calculating the pointing direction command value of the antenna from the tracking error signal from the tracking sensor, output of the relative angle calculation unit, attitude error correction value and bias error estimated value A switch for selecting the output of the adder or the output of the error signal processing unit according to the communication status of the antenna, Serial inputs the output of the directional direction command value of the selected antenna and the angle sensor in the switch, the directivity control apparatus of a communication antenna, characterized in that a servo controller for controlling the antenna drive mechanism. 4. A pointing sensor for an antenna mounted on a spacecraft, which communicates between spacecraft, and a tracking sensor for detecting a tracking error with a partner spacecraft, and an angle for detecting a driving angle of the antenna. A sensor, an antenna drive mechanism,
Communicates with the ground station directional antenna tracking unit that detects the attitude error of the spacecraft with respect to the earth by performing antenna tracking for the ground station, and the attitude error correction value calculation unit that calculates the attitude error correction value based on the above attitude error. An orbit propagation unit that predicts the orbital position of one spacecraft and outputs the orbital data, and a relative angle calculation unit that calculates the relative angle between the spacecraft on the other side from the orbital data and calculates the pointing direction command value of the antenna , A bias error model calculation unit that calculates a bias error estimated value from the trajectory data, an error signal processing unit that calculates a pointing direction command value of the antenna from a tracking error signal from the tracking sensor, and an output of the relative angle calculation unit , An adder that adds the attitude error correction value and the bias error estimated value to generate an antenna pointing direction command value, and the output of the adder or the above according to the communication status of the antenna. A switch for selecting the output of the difference signal processing unit, and a servo control unit for controlling the antenna drive mechanism by inputting the pointing direction command value of the antenna selected by the switch and the output of the angle sensor are provided. A pointing control device for a communication antenna.