A spread spectrum TT&C data transmission integrated machine interference identification and filtering system

Abstract

The present application relates to satellite TT&C data transmission technical field, disclose a kind of spread spectrum TT&C data transmission integrated machine interference identification and filtering system.The system is through on-board TT&C data transmission integrated machine and ground interference identification extraction unit collaborative work.After the interference signal containing received by TT&C antenna is converted by A / D, it is transmitted in two ways: one way is original signal, another way is frequency domain signal after FFT transformation.After receiving, accurate analysis is carried out by interference identification extraction unit, interference frequency point parameter is generated, and is uploaded to on-board through TT&C uplink channel.According to the parameter, interference is zeroed in frequency domain, and is recovered as clean time domain signal after IFFT transformation to demodulate.The present application places complex interference identification task on ground, uses powerful processing capacity and artificial judgment of ground, realizes accurate identification and dynamic filtering to interference, significantly improves the anti-interference ability and reliability of system.

Description

Technical Field

[0001] This invention relates to the field of satellite telemetry, tracking, and command (TT&C) data transmission technology, specifically to a spread spectrum TT&C data transmission integrated interference identification and filtering system. Background Technology

[0002] Currently, the amount of data from commercial remote sensing satellites is increasing dramatically, and the increase in the number of satellites is causing frequency congestion. Satellite telemetry and control is a basic condition for ensuring the normal operation of satellites. Spread spectrum telemetry and control has a certain anti-interference capability, generally resisting single-frequency or multi-frequency interference within 20dB. Since the uplink received signal itself is relatively weak, the telemetry and control reception will be affected if strong interference occurs. Therefore, it is necessary to study how to improve the robustness and anti-interference capability of satellite telemetry and control. Summary of the Invention

[0003] In view of this, the present invention provides an interference identification and filtering system for a spread spectrum telemetry and control integrated machine, which is used for interference identification and interference processing of satellite spread spectrum telemetry and control under interference conditions.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A spread spectrum telemetry and data transmission integrated machine interference identification and filtering system includes a ground telemetry and control uplink unit, a ground data transmission receiving unit, an interference identification and extraction unit, a telemetry and control integrated machine, a telemetry and control antenna, and a data transmission antenna. The telemetry and control integrated machine consists of a telemetry and control channel, a telemetry and control receiving frequency domain interference processing unit, and a data transmission channel.

[0006] The telemetry and control antenna receives a wireless signal containing interference, converts it into a digital signal through the telemetry and control channel, and sends it to the telemetry and control receiving frequency domain interference processing unit for FFT transformation.

[0007] The digital signals generated by the telemetry and control channel and the frequency domain signals generated by the telemetry and control receiving frequency domain interference processing unit are transmitted to the ground through the data transmission channel and data transmission antenna; the ground data transmission receiving unit receives and forwards the data to the interference identification and extraction unit.

[0008] The interference identification and extraction unit analyzes the downlink signal to obtain the location of the interference signal and generates interference frequency parameters. The interference frequency parameters are sent to the satellite through the ground telemetry and control uplink unit. After being received by the telemetry and control channel, the telemetry and control receiving frequency domain interference processing unit performs interference filtering based on the interference frequency parameters.

[0009] Furthermore, the integrated telemetry and control data transmission unit also includes a telemetry and control receiving unit; the telemetry and control uplink signal received by the telemetry and control antenna is transmitted down to the ground through the data transmission channel. After receiving the telemetry and control uplink signal, the ground data transmission receiving unit forwards it to the interference identification and extraction unit. The interference identification and extraction unit performs interference identification and extraction on the telemetry and control uplink signal, generates anti-interference frequency parameters, and sends them to the satellite through the ground telemetry and control uplink unit. The parameters are then injected into the telemetry and control receiving frequency domain interference processing unit for corresponding interference processing. The processed signal enters the telemetry and control receiving unit of the integrated telemetry and control data transmission unit for demodulation.

[0010] The advantages of adopting the above-mentioned optimized technical solution compared with the existing one are as follows:

[0011] Traditionally, after FFT frequency domain transformation, interference processing in the frequency domain requires pre-setting strategies for on-board equipment to automatically identify and eliminate interference. However, the interference is invisible to ground personnel, making it impossible to obtain specific information about it. Furthermore, the interference elimination strategy for on-board equipment cannot be set, and the outcome of interference elimination is unpredictable. This application utilizes the high-speed data transmission channel in the integrated telemetry and data transmission unit to uniformly transmit the raw information received by the telemetry and control antenna and the information after FFT frequency domain transformation to the ground for analysis. Ground personnel can use various processing and identification software to perform interference analysis, extract more accurate interference frequency parameters, and upload these parameters to the satellite for frequency domain interference filtering, thereby improving the effectiveness of interference elimination. Attached Figure Description

[0012] Figure 1 This is a principle block diagram of an embodiment of the present invention.

[0013] Figure 2 This is a schematic diagram of the principle structure of an embodiment of the present invention. Detailed Implementation

[0014] The present invention will now be described in further detail with reference to the accompanying drawings.

[0015] This embodiment specifically describes a spread spectrum telemetry, control, and data transmission integrated machine interference identification and filtering system, which includes a ground telemetry, control uplink unit 5, a ground data transmission receiving unit 6, an interference identification and extraction unit 7, a telemetry, control, and data transmission integrated machine 8, a telemetry, control antenna 9, and a data transmission antenna 10; wherein the telemetry, control, and data transmission integrated machine 8 consists of a telemetry, control channel 1, a telemetry, control receiving frequency domain interference processing unit 2, a telemetry, control receiving unit 3, and a data transmission channel 4, as detailed in the following reference. Figure 1 .

[0016] The measurement and control antenna 9 receives a wireless signal containing interference, converts it into a digital signal through the measurement and control channel 1, and sends it to the measurement and control receiving frequency domain interference processing unit 2 for FFT transformation.

[0017] The digital signal generated by the telemetry and control channel 1 and the frequency domain signal generated by the telemetry and control receiving frequency domain interference processing unit 2 are transmitted to the ground through the data transmission channel 4 and the data transmission antenna 10; the ground data transmission receiving unit 6 receives and forwards the data to the interference identification and extraction unit 7.

[0018] Interference identification and extraction unit 7 analyzes the downlink signal to obtain the interference signal frequency and generates interference frequency parameters. The interference frequency parameters are sent to the satellite through ground telemetry and control uplink unit 5. After being received by telemetry and control channel 1, the interference is filtered out by telemetry and control receiving frequency domain interference processing unit 2 according to the interference frequency parameters.

[0019] The telemetry and control uplink signal received by the telemetry and control antenna 9 is transmitted to the ground through the data transmission channel 4. The ground data transmission receiving unit 6 receives and forwards the signal to the interference identification and extraction unit 7. The interference identification and extraction unit 7 performs interference identification and extraction on the telemetry and control uplink signal, generates anti-interference frequency parameters, and sends them to the satellite through the ground telemetry and control uplink unit 5. The parameters are then injected into the telemetry and control receiving frequency domain interference processing unit 2 for corresponding interference processing. The processed signal enters the telemetry and control receiving unit 3 for demodulation.

[0020] In this embodiment, the measurement and control channel 1 consists of a measurement and control frequency conversion amplifier module 1-1 and a measurement and control A / D conversion module 1-2.

[0021] The measurement and control receiving frequency domain interference processing unit 2 consists of an FFT frequency domain transformation module 2-1, an FFT frequency domain interference processing module 2-2, and an IFFT time domain transformation module 2-3. The measurement and control receiving frequency domain interference processing unit 2 performs an FFT frequency domain transformation on the sampled original signal, converting the real domain signal into a frequency domain signal. The number of FFT transformation points is generally 8192. The interference signal is generally a strong single-carrier or multi-carrier signal. The frequency domain signal can identify the frequency point and magnitude of the interference signal. The FFT frequency domain interference processing module 2-2 completes the elimination of the interference frequency by using the direct zeroing method. Based on the interference frequency point parameters sent by the measurement and control demodulation module 3-1 of the measurement and control receiving unit 3, the position of the specific interference frequency is obtained, and the value of the corresponding interference frequency position is forcibly set to zero. Since the normal signal is a spread-spectrum broadband signal, setting a small number of frequency points to zero will not affect the normal signal. After the interference-processed frequency domain signal is processed by the IFFT time domain transformation module 2-3, it is restored to the normal time domain signal after interference elimination.

[0022] Data transmission channel 4 consists of a high-speed data transmission framing module 4-1, a data transmission encoding and modulation module 4-2, a data transmission D / A conversion module 4-3, and a high-speed data transmission frequency conversion amplifier module 4-4;

[0023] During normal operation of the data transmission, the high-speed data transmission framing module 4-1 transmits normal high-speed data at a transmission rate of hundreds of Mbps. As needed, the data from the measurement and control A / D conversion module 1-2 and the data from the FFT frequency domain transformation module 2-1 can be framed separately and then transmitted. The timing and duration of the frame transmission can be set by command.

[0024] The data from the telemetry and control A / D conversion module 1-2 and the FFT frequency domain transformation module 2-1 are framed in a special way. After the ground data transmission receiving unit 6 receives the data normally, it extracts the special frame and sends it to the interference identification and extraction unit 7. The interference identification and extraction unit 7 uses MATLAB or other signal analysis tools to perform frequency domain analysis on the data generated by the telemetry and control A / D conversion module 1-2 to obtain the interference frequency point. It then compares the data with the data generated by the onboard FFT frequency domain transformation module 2-1 to manually determine the specific location of the interference frequency and generate the interference frequency point parameters.

[0025] The following is a detailed reference. Figure 2 The specific implementation process of this embodiment will be further explained below:

[0026] The wide-beam signal received by the telemetry and control antenna 9 is sent to the telemetry and control frequency conversion amplifier module 1-1. The frequency-converted and amplified signal is then sent to the telemetry and control A / D conversion module 1-2 to be converted into a digital signal.

[0027] The digital signal output by the measurement and control A / D conversion module 1-2 is divided into two paths. One path is sent to the high-speed data transmission framing module 4-1 for framing processing, and the other path is sent to the FFT frequency domain transformation module 2-1 for FFT transformation before being sent to the high-speed data transmission framing module 4-1 for framing processing.

[0028] The signal after unified framing by the high-speed data transmission framing module 4-1 is sent to the data transmission encoding and modulation module 4-2 for data encoding and intermediate frequency modulation. The signal generated by the data transmission encoding and modulation module 4-2 is sent to the data transmission D / A conversion module 4-3, which converts it into an analog intermediate frequency signal and sends it to the high-speed data transmission frequency conversion and amplification module 4-4 for radio frequency frequency conversion and amplification. The amplified signal is sent to the data transmission antenna 10 and wirelessly transmitted to the ground.

[0029] After receiving the satellite data, the ground data receiving unit 6 extracts the information from the telemetry and control A / D conversion module 1-2 and the information from the FFT frequency domain transformation module 2-1, and sends them to the interference identification and extraction unit 7.

[0030] Interference identification and extraction unit 7 performs spectrum analysis on the original on-board information generated by the telemetry and control A / D conversion module 1-2 to obtain the interference spectrum, and compares it with the spectrum of the FFT frequency domain transformation module 2-1 to generate interference frequency point parameters that need to be eliminated.

[0031] The interference frequency parameters generated by the interference identification and extraction unit 7 are sent to the satellite via the ground telemetry and control uplink unit 5. After being received by the telemetry and control antenna 9, the interference frequency parameters are demodulated by the telemetry and control frequency conversion amplification module 1-1, the telemetry and control A / D conversion module 1-2 and the telemetry and control demodulation module 3-1, and then sent to the FFT frequency domain interference processing module 2-2.

[0032] The FFT frequency domain interference processing module 2-2 removes the interference frequency points in the frequency domain according to the interference frequency point parameters. The removed frequency domain signal is then sent to the IFFT time domain transformation module 2-3 to convert the frequency domain signal into a real-time time domain signal.

[0033] The time-domain signal converted by the IFFT time-domain transformation module 2-3 is the signal after interference cancellation. This signal is sent to the measurement and control demodulation module 3-1 for normal data demodulation and reception.

[0034] This embodiment utilizes a high-speed data transmission channel to transmit the raw signals received from the telemetry and control uplink and the signals transformed by the onboard FFT to the ground. After interference analysis on the ground, the interference location information is uploaded to the satellite through the telemetry and control uplink channel. The satellite performs interference processing in the frequency domain and converts it to the time domain to achieve interference cancellation. This is beneficial for ground personnel to obtain information about the interference situation on the satellite and formulate interference avoidance parameters accordingly.

Claims

1. A spread spectrum TT&C data transmission integrated machine interference identification and filtering system, comprising a ground TT&C uplink unit (5), a ground data transmission receiving unit (6), an interference identification and extraction unit (7), a TT&C data transmission integrated machine (8), a TT&C antenna (9) and a data transmission antenna (10), characterized in that, The measurement and control data transmission integrated machine (8) is composed of a measurement and control channel (1), a measurement and control receiving frequency domain interference processing unit (2) and a data transmission channel (4); The measurement and control antenna (9) receives wireless signals containing interference, converts the signals into digital signals through the measurement and control channel (1), and sends the signals to the measurement and control receiving frequency domain interference processing unit (2) for FFT transformation; The digital signals generated by the measurement and control channel (1) and the frequency domain signals generated by the measurement and control receiving frequency domain interference processing unit (2) are transmitted to the ground through the data transmission channel (4) and the data transmission antenna (10); the ground data transmission receiving unit (6) receives the signals and transmits the signals to the interference identification extraction unit (7); The interference identification extraction unit (7) analyzes the transmitted signals to obtain the position of the interference signals and generates interference frequency point parameters; the interference frequency point parameters are sent to the satellite through the ground measurement and control uplink unit (5), received by the measurement and control channel (1), and filtered by the measurement and control receiving frequency domain interference processing unit (2) according to the interference frequency point parameters; The measurement and control data transmission integrated machine (8) further comprises a measurement and control receiving unit (3); the measurement and control uplink signals received by the measurement and control antenna (9) are transmitted to the ground through the data transmission channel (4), received by the ground data transmission receiving unit (6) and transmitted to the interference identification extraction unit (7); the interference identification extraction unit (7) identifies and extracts the interference of the measurement and control uplink signals to generate interference frequency point parameters, which are sent to the satellite through the ground measurement and control uplink unit (5) and injected into the measurement and control receiving frequency domain interference processing unit (2) for corresponding interference processing; the processed signals are demodulated by the measurement and control receiving unit (3).

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