S / C frequency band ground-satellite integrated TT&C terminal

Abstract

The application discloses a kind of S / C frequency band ground-based integrated TT&C terminal, by ground uplink matrix instruction or according to the power strength of the uplink signal received by current radio frequency receiving channel, the corresponding baseband processing program is switched from autonomous, intelligent processing the uplink signal received by the radio frequency receiving channel of current equipment, demodulates remote control instruction and ranging tone, and telemetry and ranging tone are modulated according to the frequency band currently worked and sent to the corresponding radio frequency transmitting channel.The design method realizes the automatic / manual switching use of S frequency band TDRSS space-based spread spectrum transponder function and C frequency band unified carrier system TT&C ground-based TT&C function on the basis of a set of digital processing hardware platform, greatly improves the TT&C capability and TT&C range of satellite, reduces the weight, volume and power consumption of similar products, and is functional, which can be widely applied to aircraft with relay TT&C requirements;It can also be applied to aircraft based on ground-based TT&C, and the relay function is used as backup.

Description

Technical Field

[0001] This invention relates to an S / C band space-ground integrated telemetry and control terminal, belonging to the field of satellite measurement and control technology. Background Technology

[0002] With the development of the space industry, the number of satellites in orbit is increasing year by year, which places high demands on the coverage of satellite telemetry, tracking, and command (TT&C) systems. Currently, the main systems supporting TT&C include: ground-based TT&C systems and tracking and data relay systems (space-based TT&C systems).

[0003] Tracking and data relay systems have also significantly improved the efficiency of space information transmission and expanded the coverage of satellite telemetry, tracking, and command. Currently, the second-generation relay satellite system is already in use.

[0004] To obtain timely telemetry data for the entire satellite and to control and monitor its attitude in a timely manner, a relay terminal is often used in the satellite's design. Once the satellite enters the orbit determination and operation phase, the telemetry, tracking, and command (TT&C) transponder will be responsible for exchanging data with the ground monitoring station. At this time, the relay terminal is generally kept as a cold backup.

[0005] To adapt to the different telemetry and control requirements of high-orbit satellites during the orbit change and orbit determination phases, fully leverage the advantages of the space telemetry and control network, improve satellite telemetry and control capabilities and coverage, and rationally optimize satellite spatial layout, mass, and power consumption, a space-based integrated telemetry and control terminal capable of operating in both S-band and C-band has received significant attention. There is an urgent need for an S / C-band space-based integrated telemetry and control terminal that can switch between different baseband processing programs and operating frequency bands based on the signal strength of the receiving channel or ground commands. Summary of the Invention

[0006] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide an S / C band integrated space-ground telemetry and control terminal. The design concept is that the S-band radio frequency transceiver channel and the C-band radio frequency transceiver channel share a set of digital processing modules. Different baseband processing programs can be switched through automatic / manual commands to realize the differentiated telemetry and control needs of the entire satellite.

[0007] The technical solution of this invention is:

[0008] This invention discloses an S / C band integrated space-ground telemetry and control terminal, comprising an S-band radio frequency transceiver channel, a C-band radio frequency transceiver channel, and a digital processing module; wherein,

[0009] The S-band RF transceiver channel down-converts the S-band RF input signal to an S-band baseband signal and sends it to the digital processing module; it up-converts the modulated S-band baseband signal sent by the digital processing module to an S-band RF signal output; and it sends an S-band analog AGC level to the digital processing module.

[0010] The C-band RF transceiver channel down-converts the C-band RF input signal to a C-band baseband signal and sends it to the digital processing module; it up-converts the modulated C-band baseband signal sent by the digital processing module to a C-band RF signal output and provides a clock source for synchronization between the S-band RF transceiver channel and the digital processing module; and it sends C-band analog AGC level signals to the digital processing module.

[0011] The digital processing module performs S-band remote control signal processing on the S-band baseband signal transmitted by the S-band RF transceiver channel, tracks and demodulates the uplink signal, and outputs the S-band remote control command and S-band ranging tone. It also performs C-band remote control signal processing on the C-band baseband signal transmitted by the C-band RF transceiver channel, tracks and demodulates the uplink signal, and outputs the C-band remote control command and C-band ranging tone. Furthermore, it processes the S-band telemetry signal and ranging tone transmitted by the host computer to generate a modulated S-band baseband signal, which is then sent to the S-band RF transceiver channel. Similarly, it processes the C-band telemetry signal and ranging tone transmitted by the host computer to generate a modulated C-band baseband signal, which is then sent to the C-band RF transceiver channel. Finally, it performs mode switching based on the S-band analog AGC level of the S-band RF transceiver channel and the C-band analog AGC level of the C-band RF transceiver channel.

[0012] In the aforementioned integrated measurement and control terminal, the S-band RF transceiver channel includes an S-band RF receiving channel and an S-band RF transmitting channel. The S-band RF receiving channel includes a low-noise amplifier, mixer, amplifier, adjustable attenuator, low-pass filter, and AGC circuit. After performing low-noise amplification, mixing, amplification, attenuation adjustment, low-pass filtering, and AGC automatic gain control on the received S-band RF signal, it outputs an S-band baseband signal. The S-band RF transmitting channel includes a mixer, filter, amplifier, power divider, and detector. After performing mixing, filtering, amplification, power division, and detection on the received baseband signal, it outputs an S-band RF signal. The S-band RF receiving channel outputs an S-band analog AGC level to the digital processing module.

[0013] Furthermore, in the aforementioned integrated measurement and control terminal, the C-band RF transceiver channel includes a C-band RF receiving channel, a C-band RF transmitting channel, and a clock source module. The C-band RF receiving channel includes a low-noise amplifier, a mixer, an amplifier, an adjustable attenuator, a low-pass filter, and an AGC circuit. After performing low-noise amplification, mixing, amplification, attenuation adjustment, low-pass filtering, and AGC automatic gain control on the received C-band RF signal, it outputs a C-band baseband signal. The C-band RF receiving channel outputs a C-band analog AGC level to the digital processing module. The C-band RF transmitting channel includes a mixer, a filter, an amplifier, a power divider, and a detector. After performing mixing, filtering, amplification, power division, and detection on the received baseband signal, it outputs a C-band RF signal. The clock source module includes a 10MHz crystal oscillator, providing clock signals to the C-band RF transceiver channel, the S-band RF transceiver channel, and the digital processing module.

[0014] Furthermore, in the aforementioned integrated telemetry and control terminal, the digital processing module includes an S-band space-based signal processing module, a C-band ground-based signal processing module, a baseband processing program refresh module, and a PROM; wherein, the PROM includes PROM1 and PROM2; PROM1 is used to run the C-band ground-based signal processing module, and PROM2 is used to run the S-band space-based signal processing module; the baseband processing program refresh module receives uplink commands sent from the ground to power on / off the PROM, or enables PROM1 or PROM2 according to the S-band simulated AGC level of the S-band RF transceiver channel and the C-band simulated AGC level of the C-band RF transceiver channel, thereby achieving mode switching.

[0015] Furthermore, in the aforementioned integrated telemetry and control terminal, the S-band space-based signal processing module performs S-band remote control signal processing on the received S-band baseband signal, tracks and demodulates the uplink signal, performs spread spectrum despreading processing, and decodes the S-band remote control command and S-band ranging tone; and transparently forwards or transcodes the S-band telemetry signal and ranging tone sent by the host computer to the S-band transmit and receive channel.

[0016] The C-band space-based signal processing module processes the received C-band baseband signal into a C-band remote control signal, tracks and demodulates the uplink signal, performs unified carrier demodulation, and extracts the C-band remote control command and C-band ranging tone. It then transparently forwards or transcodes the C-band telemetry signal and ranging tone sent by the host computer to the C-band transmit / receive channel.

[0017] Furthermore, in the aforementioned integrated measurement and control terminal, the baseband processing program refresh module includes a power comparison module and a matrix instruction module. The power comparison module receives the S-band analog AGC level from the S-band RF transceiver channel and the C-band analog AGC level from the C-band RF transceiver channel, sends them to a comparator to generate a judgment state value, and then directly sends it to the enable terminal of PROM1. After inversion, it is simultaneously sent to the enable terminal of PROM2, enabling either PROM1 or PROM2 to achieve mode switching. The matrix instruction module receives uplink commands transmitted from the ground and controls the on / off state of relays to power on / off the PROM storing the processing program.

[0018] Furthermore, in the aforementioned integrated telemetry and control terminal, the C-band ground-based signal processing module includes: an analog-to-digital converter (ADC1), a C-band quadrature down-conversion module, a C-band low-pass filter module, a C-band CIC filter module, a C-band carrier discrimination, acquisition, and tracking module, a C-band remote control subcarrier demodulation module, a C-band ranging, demodulation, and forwarding module, a C-band telemetry signal processing module, and a digital-to-analog converter (DAC1); wherein,

[0019] The analog-to-digital converter ADC1 converts the C-band baseband signal transmitted by the C-band RF receiving channel from analog to digital.

[0020] The C-band quadrature downconversion module generates a baseband signal after performing quadrature downconversion.

[0021] The C-band low-pass filter module and the C-band CIC filter module perform low-pass filtering and CIC filtering on the baseband signal, respectively. The filtered baseband signal is then sent to the C-band carrier frequency discrimination, acquisition, and tracking module for feedback processing until it stabilizes, completing the acquisition and tracking. The stabilized baseband signal is then sent to the C-band remote control subcarrier demodulation module and the C-band ranging demodulation and forwarding module. Simultaneously, the C-band telemetry signal processing module performs PM modulation on the PSK code and ranging tone of the C-band telemetry signal sent by the host computer and sends it to the C-band RF transmission channel. Alternatively, it performs PSK modulation on the PCM code stream of the C-band telemetry signal sent by the host computer, then PM modulation, performs digital-to-analog conversion through DAC1, and then sends it to the C-band RF transmission channel.

[0022] Furthermore, in the aforementioned integrated telemetry and control terminal, the S-band space-based signal processing module includes: an analog-to-digital converter (ADC2), an S-band anti-interference module, an S-band FFT module, an S-band acquisition module, an S-band signal tracking module, an S-band remote control signal processing module, an S-band ranging signal processing module, an S-band telemetry data framing module, and a digital-to-analog converter (DAC2); among which,

[0023] The analog-to-digital converter ADC2 converts the S-band baseband signal from analog to digital and sends it to the S-band anti-interference module.

[0024] The S-band anti-interference module performs FFT operation on the digital signal and sends the FFT data to the S-band FFT module.

[0025] The S-band FFT module performs IFFT transformation on the FFT data to obtain the anti-interference digital baseband signal, which is then output to the S-band acquisition module.

[0026] The S-band acquisition module performs acquisition processing on the digital baseband signal after anti-interference, obtains the acquisition processing result, and sends it to the S-band signal tracking module.

[0027] The S-band signal tracking module performs frame synchronization on the acquisition and processing results, decodes the remote control signal and ranging tone, sends the remote control signal to the S-band remote control signal processing module, and sends the ranging tone to the S-band ranging signal processing module.

[0028] The S-band remote control signal processing module outputs a remote control data stream and a corresponding remote control clock based on the remote control signal.

[0029] The S-band ranging signal processing module forwards the ranging tone to the S-band telemetry data framing module.

[0030] The S-band telemetry data framing module modulates the ranging tone and the S-band telemetry signal sent by the host computer to generate a downlink baseband signal and outputs the modulated S-band baseband signal.

[0031] Furthermore, in the aforementioned integrated measurement and control terminal, the acquisition processing specifically includes:

[0032] A regenerated carrier is generated to downconvert the interfered digital baseband signal, thus completing carrier stripping.

[0033] Perform correlation operations on the data group codes after carrier stripping, and then accumulate them;

[0034] Perform an FFT on the accumulated data, and then perform a detection and judgment on the FFT result;

[0035] Capture the data based on the detection and judgment results, and output the capture processing results.

[0036] In the aforementioned integrated measurement and control terminal, the acquisition processing results include the pseudo-code phase of the spread spectrum signal, a rough estimate of the carrier Doppler frequency shift, and the acquisition status.

[0037] The advantages of this invention over the prior art are as follows:

[0038] (1) The S / C band space-ground integrated telemetry and control terminal of the present invention, compared with the conventional S band space-based relay terminal and C band ground-based telemetry and control transponder, can simultaneously possess the capability of a space-ground integrated telemetry and control terminal, saving half the number of products. Under the premise of achieving the same function, it effectively reduces the weight, volume and power consumption of the satellite platform. It is an integrated, miniaturized and integrated design with obvious advantages.

[0039] (2) The S / C band space-ground integrated telemetry and control terminal of the present invention has a dual-mode design for manual / automatic processing of the baseband processing program refresh module, which can realize active switching between the S band space-based signal processing module and the C band ground-based signal processing module, and can also manually set and select the S band space-based signal processing module and the C band ground-based signal processing module according to the needs of satellite users and actual needs.

[0040] (3) This invention can adapt to different types of telemetry data (PSK modulated telemetry data / telemetry PCM code data) sent from the host computer to the S / C band space-ground integrated telemetry and control terminal, and switch different working modes according to the instructions to perform different processing on the telemetry data sent by the host computer.

[0041] (4) The S / C band space-ground integrated telemetry and control terminal of the present invention has the characteristics of strong functional and performance scalability, and can realize space-based telemetry and control and ground-based telemetry and control on the same hardware platform; in addition, according to different needs, while keeping the hardware design unchanged, the signal processing module in the digital processing module can be changed to realize the unified carrier system telemetry and control of the S band. It can solve the problem of mass production and mass launch of satellites with multi-band telemetry and control requirements.

[0042] (5) The S / C band integrated ground-to-ground measurement and control terminal of the present invention has a frequency accuracy of 1kHz for the S band transmitting / receiving local oscillator and the C band transmitting / receiving local oscillator. The frequency accuracy is high. In view of the increasingly tight frequency resources, it can adapt to different frequency point requirements without changing the circuit design, effectively solve the current situation of frequency resource conflict, and reduce frequency resource coordination problems.

[0043] (6) The S / C band integrated ground-based telemetry and control terminal of this invention can output the S-band and C-band downlink signals simultaneously, or select to output a single signal as needed. With the adaptive selection of uplink signals, multiple working modes can be selected under one product, making the product highly adaptable and practical. Attached Figure Description

[0044] Figure 1 This is a block diagram illustrating the working principle of the present invention;

[0045] Figure 2This is a block diagram illustrating the working principle of the C-band radio frequency transceiver module described in this invention;

[0046] Figure 3 This is a block diagram illustrating the working principle of the S-band radio frequency transceiver module described in this invention;

[0047] Figure 4 This is a block diagram illustrating the working principle of the C-band ground-based signal processing module described in this invention.

[0048] Figure 5 This is a block diagram illustrating the working principle of the S-band space-based signal processing module described in this invention.

[0049] Figure 6 This is a block diagram illustrating the working principle of the baseband processing program refresh module described in this invention. Detailed Implementation

[0050] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0051] like Figure 1 As shown, this invention discloses an S / C band integrated space-ground telemetry and control terminal, including an S-band radio frequency transceiver channel, a C-band radio frequency transceiver channel, and a digital processing module; wherein,

[0052] The S-band RF transceiver channel down-converts the S-band RF input signal to an S-band baseband signal and sends it to the digital processing module; it up-converts the modulated S-band baseband signal sent by the digital processing module to an S-band RF signal output; and it sends an S-band analog AGC level to the digital processing module.

[0053] The C-band RF transceiver channel down-converts the C-band RF input signal to a C-band baseband signal and sends it to the digital processing module; it up-converts the modulated C-band baseband signal sent by the digital processing module to a C-band RF signal output and provides a clock source for synchronization between the S-band RF transceiver channel and the digital processing module; and it sends C-band analog AGC level signals to the digital processing module.

[0054] The digital processing module performs S-band remote control signal processing on the S-band baseband signal transmitted by the S-band RF transceiver channel, tracks and demodulates the uplink signal, and outputs the S-band remote control command and S-band ranging tone. It also performs C-band remote control signal processing on the C-band baseband signal transmitted by the C-band RF transceiver channel, tracks and demodulates the uplink signal, and outputs the C-band remote control command and C-band ranging tone. Furthermore, it processes the S-band telemetry signal and ranging tone transmitted by the host computer to generate a modulated S-band baseband signal, which is then sent to the S-band RF transceiver channel. Similarly, it processes the C-band telemetry signal and ranging tone transmitted by the host computer to generate a modulated C-band baseband signal, which is then sent to the C-band RF transceiver channel. Finally, it performs mode switching based on the S-band analog AGC level of the S-band RF transceiver channel and the C-band analog AGC level of the C-band RF transceiver channel.

[0055] like Figure 2 As shown, the S-band RF transceiver channel includes an S-band RF receiving channel and an S-band RF transmitting channel. The S-band RF receiving channel includes a low-noise amplifier, mixer, amplifier, adjustable attenuator, low-pass filter, and AGC circuit. It performs low-noise amplification, mixing, amplification, attenuation adjustment, low-pass filtering, and AGC automatic gain control on the received S-band RF signal, and then outputs an S-band baseband signal. The S-band RF transmitting channel includes a mixer, filter, amplifier, power divider, and detector. It performs mixing, filtering, amplification, power division, and detection on the received baseband signal, and then outputs an S-band RF signal. The S-band RF receiving channel outputs an S-band analog AGC level to the digital processing module.

[0056] like Figure 3 As shown, the C-band RF transceiver channel includes a C-band RF receiving channel, a C-band RF transmitting channel, and a clock source module. The C-band RF receiving channel includes a low-noise amplifier, mixer, amplifier, adjustable attenuator, low-pass filter, and AGC circuit. It performs low-noise amplification, mixing, amplification, attenuation adjustment, low-pass filtering, and AGC automatic gain control on the received C-band RF signal, outputting a C-band baseband signal. The C-band RF receiving channel outputs a C-band analog AGC level to the digital processing module. The C-band RF transmitting channel includes a mixer, filter, amplifier, power divider, and detector. It performs mixing, filtering, amplification, power division, and detection on the received baseband signal, outputting a C-band RF signal. The clock source module includes a 10MHz crystal oscillator, providing clock signals to the C-band RF transceiver channel, S-band RF transceiver channel, and digital processing module.

[0057] like Figure 1As shown, the digital processing module includes an S-band space-based signal processing module, a C-band ground-based signal processing module, a baseband processing program refresh module, and a PROM; wherein, the PROM includes PROM1 and PROM2; PROM1 is used to load the C-band ground-based signal processing module, and PROM2 is used to load the S-band space-based signal processing module; the baseband processing program refresh module receives uplink commands sent from the ground to enable or disable the PROM, or enables PROM1 and PROM2 according to the S-band analog AGC level of the S-band RF transceiver channel and the C-band analog AGC level of the C-band RF transceiver channel, thereby realizing mode switching.

[0058] The S-band space-based signal processing module processes the received S-band baseband signal into an S-band remote control signal, tracks and demodulates the uplink signal, performs despreading processing of the spread spectrum system, and decodes the S-band remote control command and S-band ranging tone. It then transparently forwards or transcodes the S-band telemetry signal and ranging tone sent by the host computer to the S-band transmit / receive channel.

[0059] The C-band space-based signal processing module processes the received C-band baseband signal into a C-band remote control signal, tracks and demodulates the uplink signal, performs unified carrier demodulation, and extracts the C-band remote control command and C-band ranging tone. It then transparently forwards or transcodes the C-band telemetry signal and ranging tone sent by the host computer to the C-band transmit / receive channel.

[0060] The baseband processing program refresh module includes a power comparison module and a matrix instruction module. The power comparison module receives the S-band analog AGC level from the S-band RF transceiver channel and the C-band analog AGC level from the C-band RF transceiver channel, sends them to the comparator, generates a judgment status quantity, directly sends it to the enable terminal of PROM1, and after inversion, simultaneously sends it to the enable terminal of PROM2 to enable either PROM1 or PROM2, thereby realizing mode switching. The matrix instruction module receives uplink commands transmitted from the ground and controls the on / off state of relays to power on / off the PROM storing the processing program.

[0061] like Figure 4As shown, the C-band ground-based signal processing module includes: an analog-to-digital converter (ADC1), a C-band quadrature down-conversion module, a C-band low-pass filter module, a C-band CIC filter module, a C-band carrier discrimination, acquisition, and tracking module, a C-band remote control subcarrier demodulation module, a C-band ranging, demodulation, and forwarding module, a C-band telemetry signal processing module, and a digital-to-analog converter (DAC1). The ADC1 converts the C-band baseband signal transmitted from the C-band RF receiving channel from analog to digital. The C-band quadrature down-conversion module performs quadrature down-conversion to form the baseband signal. The C-band low-pass filter module and the C-band CIC filter module perform low-pass down-conversion on the baseband signal. The system performs pass filtering and CIC filtering, sending the filtered baseband signal to the C-band carrier frequency discrimination, acquisition, and tracking module. After feedback processing, the signal stabilizes, completing acquisition and tracking. The stabilized baseband signal is then sent to the C-band remote control subcarrier demodulation module and the C-band ranging demodulation and forwarding module. Simultaneously, the C-band telemetry signal processing module performs PM modulation on the PSK code and ranging tone of the C-band telemetry signal sent by the host computer and sends it to the C-band RF transmission channel. Alternatively, it performs PSK modulation on the PCM code stream of the C-band telemetry signal sent by the host computer, then PM modulation, performs digital-to-analog conversion through DAC1, and then sends it to the C-band RF transmission channel.

[0062] like Figure 5 As shown, the S-band space-based signal processing module includes: an analog-to-digital converter (ADC2), an S-band anti-interference module, an S-band FFT module, an S-band acquisition module, an S-band signal tracking module, an S-band remote control signal processing module, an S-band ranging signal processing module, an S-band telemetry data framing module, and a digital-to-analog converter (DAC2). The ADC2 converts the S-band baseband signal from analog to digital and sends it to the S-band anti-interference module. The S-band anti-interference module performs an FFT operation on the digital signal and sends the FFT-derived data to the S-band FFT module. The S-band FFT module performs an IFFT transform on the FFT-derived data to obtain the anti-interference digital baseband signal, which is then output to the S-band acquisition module. The S-band acquisition module performs acquisition processing on the anti-interference digital baseband signal, obtains the acquisition processing result, and sends it to the S-band signal tracking module. The S-band signal tracking module performs frame synchronization on the acquisition processing result, decodes the remote control signal and ranging tone, and sends the remote control signal to the S-band remote control signal processing module. It also sends the ranging tone to the S-band ranging signal processing module. The S-band remote control signal processing module outputs the remote control data stream and the corresponding remote control clock based on the remote control signal. The S-band ranging signal processing module forwards the ranging tone to the S-band telemetry data framing module. The S-band telemetry data framing module modulates the ranging tone and the S-band telemetry signal sent by the host computer to generate a downlink baseband signal and outputs the modulated S-band baseband signal.

[0063] The S-band acquisition module performs acquisition processing on the digital baseband signal after interference, and obtains the acquisition processing result as follows:

[0064] Step S91: Generate a regenerated carrier and downconvert the digital baseband signal after interference to complete carrier stripping;

[0065] Step S92: Perform correlation calculations on the data group codes after carrier stripping, and then accumulate the results;

[0066] Step S93: Perform an FFT on the accumulated data and then perform a detection and judgment on the FFT result;

[0067] Step S94: Capture the target based on the detection decision and output the capture processing result.

[0068] The acquisition processing results include the pseudo-code phase of the spread spectrum signal, a rough estimate of the carrier Doppler frequency shift, and the acquisition status.

[0069] Example

[0070] This embodiment provides a design method for an integrated space-ground measurement and control terminal in S-band and C-band, including an S-band radio frequency transceiver channel, a C-band radio frequency transceiver channel, and a digital processing module.

[0071] The S-band radio frequency transceiver channel consists of an S-band receive channel and an S-band transmit channel, such as... Figure 1 As shown, the S-band RF receiving channel includes a low-noise amplifier, mixer, amplifier, adjustable attenuator, low-pass filter, and AGC circuit, etc.; among which,

[0072] The S-band RF receiving channel receives the S-band RF signal input from the front end. This signal is amplified by a low-noise amplifier and then down-converted. Afterward, the signal sequentially enters an attenuator and amplifier for signal matching, then passes through a filter and amplifier for further filtering, and finally enters the AGC (Automatic Gain Control) circuit for amplification, outputting a baseband signal to the digital processing unit.

[0073] The S-band RF transmitter module receives the modulated baseband signal from the digital processing unit and mixes the modulated baseband signal with a local oscillator signal generated by a PLS (phase-locked source) to obtain the first baseband signal. After low-pass filtering, the signal is sent to an amplifier. The amplified first baseband signal is mixed with a second local oscillator to obtain the S-band RF signal. After passing through a bandpass filter, the signal is amplified in multiple stages. The amplified S-band RF signal is then passed through a power divider to output two signals: one is output as a power telemetry signal via a detector, and the other is output as a downlink S-band signal.

[0074] The C-band RF transceiver channel consists of a C-band receive channel, a C-band transmit channel, and a clock source module, such as... Figure 3 As shown, the C-band RF receiving channel includes a low-noise amplifier, mixer, amplifier, adjustable attenuator, low-pass filter, and AGC circuit, etc.; among which,

[0075] The C-band RF receiving channel receives the C-band RF signal input from the front end. This signal is amplified by a low-noise amplifier and then down-converted. Afterward, the signal sequentially enters an attenuator and amplifier for signal matching, then passes through a filter and amplifier for further filtering, and finally enters the AGC (Automatic Gain Control) circuit for amplification, outputting a baseband signal to the digital processing unit.

[0076] The C-band RF transmitter module receives the modulated baseband signal from the digital processing unit and mixes it with a local oscillator signal generated by a PLS (phase-locked loop) to obtain the first baseband signal. This first baseband signal is then low-pass filtered and sent to an amplifier. The amplified first baseband signal is mixed with a second local oscillator signal to obtain the C-band RF signal. After passing through a band-pass filter, it undergoes multi-stage amplification. The amplified C-band RF signal is then divided by a power divider to output two signals: one is output as a power telemetry signal via a detector, and the other is output as a downlink C-band signal. Simultaneously, it provides a stable 10MHz clock source for the S-band RF transceiver channel.

[0077] The digital processing module includes a C-band ground-based signal processing module, an S-band space-based signal processing module, and a baseband processing program refresh module;

[0078] Among them, the C-band baseband signal processing module, such as Figure 4 As shown, it includes: ADC1 (digital-to-analog conversion), DAC1 (analog-to-digital conversion), C-band quadrature downconversion module, C-band low-pass filter module, C-band CIC filter module, C-band carrier frequency discrimination, acquisition and tracking module, C-band remote control subcarrier demodulation module, C-band ranging, demodulation and forwarding module, and C-band telemetry signal processing unit;

[0079] When processing uplink signals in the C-band ground-based unified carrier system, the C-band quadrature downconversion module first performs quadrature downconversion on the digital signal from ADC1 to form a baseband signal, then performs low-pass filtering and CIC filtering, and then sends the signal to the frequency discriminator module for feedback processing until it stabilizes, completing acquisition and tracking. The baseband signal obtained after low-pass filtering is then sent to the remote control subcarrier demodulation module and the ranging tone demodulation and forwarding module. At the same time, the telemetry PSK signal (in PSK mode) sent by the host computer is directly PM modulated along with the ranging tone and sent to DAC1; or the telemetry PCM code (in PCM mode) sent by the host computer is PSK modulated and then PM modulated before being sent to DAC1 (analog-to-digital converter).

[0080] S-band baseband signal processing module, such as Figure 5As shown, it includes: ADC2, DAC2, S-band anti-interference module, S-band FFT module, S-band acquisition module, S-band signal tracking module, S-band remote control signal processing module, S-band ranging signal processing module, and S-band telemetry data framing module.

[0081] When processing uplink signals in the S-band space-based spread spectrum system, the S-band anti-interference module performs an FFT operation on the currently input ADC2 sampled data frame. The judged data is then fed into the S-band FFT module for IFFT transformation to obtain the anti-interference data, which is output to the S-band acquisition module. The S-band acquisition module receives the anti-interference digital baseband signal, generates a regenerated carrier to down-convert the digital baseband signal, and completes carrier stripping. The carrier-stripped data undergoes code correlation operations and is then accumulated. An FFT is performed on the accumulated data, and the FFT result is used for detection and decision. To obtain a more accurate carrier value upon acquisition, the S-band carrier tracking module continuously updates the carrier frequency. Then, the pseudo-code phase of the spread spectrum signal, a coarse estimate of the carrier Doppler shift, and the acquisition status are output to the S-band signal tracking module. After the pseudo-code phase and carrier frequency tracking are locked, the S-band signal tracking module completes frame synchronization based on the remote control data. The remote control signal is then sent to the S-band remote control signal processing module to extract the remote control data stream and the corresponding remote control clock, and output them together to the downstream device. At the same time, the S-band telemetry data framing module modulates the ranging signal and telemetry signal to generate a downlink baseband signal, outputs the modulated baseband signal through DAC2, and sends the modulated baseband signal to the S-band RF transmission module.

[0082] Baseband processing refresh module, such as Figure 6 As shown, it includes: a power comparison module and a matrix instruction module.

[0083] In the digital processing module, the baseband processing program refresh module software running on the FPGA has two loading methods. The first method loads the corresponding program through the output value of the power comparator circuit. First, the power supply control switch needs to be switched to the comparator output. The power comparator circuit simultaneously receives the AGC values ​​of the S-band and C-band receiver channels, compares their magnitudes, and outputs "0" or "1" to the PROM enable terminal. An inverter is designed before the enable input of PROM2 to ensure that only one of PROM1 and PROM2 is enabled. The second method uses ground-sent matrix commands to control the activation state of the relays at the front end of the corresponding PROM power supply circuit. In this case, the enable terminal first needs to be manually switched to a constant high signal, and then the ground matrix command controls the on / off state of the relays to supply power to the PROM, thereby selecting and controlling the loading of the corresponding program in the PROM.

[0084] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

[0085] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A space-ground integrated telemetry and control terminal for S / C band, characterized in that, It includes an S-band RF transceiver channel, a C-band RF transceiver channel, and a digital processing module; among which, The S-band RF transceiver channel down-converts the S-band RF input signal to an S-band baseband signal and sends it to the digital processing module; it up-converts the modulated S-band baseband signal sent by the digital processing module to an S-band RF signal output; and it sends an S-band analog AGC level to the digital processing module. The C-band RF transceiver channel down-converts the C-band RF input signal to a C-band baseband signal and sends it to the digital processing module; it up-converts the modulated C-band baseband signal sent by the digital processing module to a C-band RF signal output and provides a clock source for synchronization between the S-band RF transceiver channel and the digital processing module; and it sends C-band analog AGC level signals to the digital processing module. The digital processing module performs S-band remote control signal processing on the S-band baseband signal transmitted by the S-band RF transceiver channel, tracks and demodulates the uplink signal, and outputs the S-band remote control command and S-band ranging tone. It also performs C-band remote control signal processing on the C-band baseband signal transmitted by the C-band RF transceiver channel, tracks and demodulates the uplink signal, and outputs the C-band remote control command and C-band ranging tone. Furthermore, it processes the S-band telemetry signal and ranging tone transmitted by the host computer to generate a modulated S-band baseband signal, which is then sent to the S-band RF transceiver channel. It also processes the C-band telemetry signal and ranging tone transmitted by the host computer to generate a modulated C-band baseband signal, which is then sent to the C-band RF transceiver channel. Finally, it performs mode switching based on the S-band analog AGC level of the S-band RF transceiver channel and the C-band analog AGC level of the C-band RF transceiver channel. The digital processing module includes an S-band space-based signal processing module, a C-band ground-based signal processing module, a baseband processing program refresh module, and a PROM; wherein, the PROM includes PROM1 and PROM2; PROM1 is used to run the C-band ground-based signal processing module, and PROM2 is used to run the S-band space-based signal processing module; the baseband processing program refresh module receives uplink commands sent from the ground to power on or off the PROM, or enables PROM1 or PROM2 according to the S-band simulated AGC level of the S-band RF transceiver channel and the C-band simulated AGC level of the C-band RF transceiver channel, thereby realizing mode switching; The baseband processing program refresh module includes a power comparison module and a matrix instruction module; wherein, The power comparison module receives the S-band analog AGC level of the S-band RF transceiver channel and the C-band analog AGC level of the C-band RF transceiver channel, sends them to the comparator, generates a judgment status quantity, and then sends it directly to the enable terminal of PROM1. After inversion, it is simultaneously sent to the enable terminal of PROM2 to enable PROM1 or PROM2, thereby realizing mode switching. The matrix instruction module receives uplink instructions sent from the ground and controls the power-on / off of the PROM storing the processing program by controlling the on / off state of the relays.

2. The S / C band space-ground integrated telemetry and control terminal according to claim 1, characterized in that: The S-band RF transceiver channel includes an S-band RF receiving channel and an S-band RF transmitting channel. The S-band RF receiving channel includes a low-noise amplifier, mixer, amplifier, adjustable attenuator, low-pass filter, and AGC circuit. It performs low-noise amplification, mixing, amplification, attenuation adjustment, low-pass filtering, and AGC automatic gain control on the received S-band RF signal, and then outputs an S-band baseband signal. The S-band RF transmitting channel includes a mixer, filter, amplifier, power divider, and detector. It performs mixing, filtering, amplification, power division, and detection on the received baseband signal, and then outputs an S-band RF signal. The S-band RF receiving channel outputs an S-band analog AGC level to the digital processing module.

3. The S / C band space-ground integrated telemetry and control terminal according to claim 1, characterized in that: The C-band RF transceiver channel includes a C-band RF receiving channel, a C-band RF transmitting channel, and a clock source module. The C-band RF receiving channel includes a low-noise amplifier, mixer, amplifier, adjustable attenuator, low-pass filter, and AGC circuit. It performs low-noise amplification, mixing, amplification, attenuation adjustment, low-pass filtering, and AGC automatic gain control on the received C-band RF signal before outputting a C-band baseband signal. The C-band RF receiving channel outputs a C-band analog AGC level to the digital processing module. The C-band RF transmitting channel includes a mixer, filter, amplifier, power divider, and detector. It performs mixing, filtering, amplification, power division, and detection on the received baseband signal before outputting a C-band RF signal. The clock source module includes a 10MHz crystal oscillator, providing clock signals to the C-band RF transceiver channel, S-band RF transceiver channel, and digital processing module.

4. The S / C band space-ground integrated telemetry and control terminal according to claim 1, characterized in that: The S-band space-based signal processing module performs S-band remote control signal processing on the received S-band baseband signal, tracks and demodulates the uplink signal, performs spread spectrum despreading processing, and decodes the S-band remote control command and S-band ranging tone; it transparently forwards or transcodes the S-band telemetry signal and ranging tone sent by the host computer to the S-band transmit and receive channel. The C-band space-based signal processing module processes the received C-band baseband signal into a C-band remote control signal, tracks and demodulates the uplink signal, performs unified carrier demodulation, and extracts the C-band remote control command and C-band ranging tone. It then transparently forwards or transcodes the C-band telemetry signal and ranging tone sent by the host computer to the C-band transmit / receive channel.

5. The S / C band space-ground integrated telemetry and control terminal according to claim 3, characterized in that: The C-band ground-based signal processing module includes: an analog-to-digital converter (ADC1), a C-band quadrature down-conversion module, a C-band low-pass filter module, a C-band CIC filter module, a C-band carrier frequency discrimination, acquisition, and tracking module, a C-band remote control subcarrier demodulation module, a C-band ranging, demodulation, and forwarding module, a C-band telemetry signal processing module, and a digital-to-analog converter (DAC1); wherein... The analog-to-digital converter ADC1 converts the C-band baseband signal transmitted by the C-band RF receiving channel from analog to digital. The C-band quadrature downconversion module generates a baseband signal after performing quadrature downconversion. The C-band low-pass filter module and the C-band CIC filter module perform low-pass filtering and CIC filtering on the baseband signal, respectively. The filtered baseband signal is then sent to the C-band carrier frequency discrimination, acquisition, and tracking module for feedback processing until it stabilizes, completing the acquisition and tracking. The stabilized baseband signal is then sent to the C-band remote control subcarrier demodulation module and the C-band ranging demodulation and forwarding module. Simultaneously, the C-band telemetry signal processing module performs PM modulation on the PSK code and ranging tone of the C-band telemetry signal sent by the host computer and sends it to the C-band RF transmission channel. Alternatively, it performs PSK modulation on the PCM code stream of the C-band telemetry signal sent by the host computer, then PM modulation, performs digital-to-analog conversion through DAC1, and then sends it to the C-band RF transmission channel.

6. The S / C band space-ground integrated telemetry and control terminal according to claim 1, characterized in that: The S-band space-based signal processing module includes: an analog-to-digital converter (ADC2), an S-band anti-interference module, an S-band FFT module, an S-band acquisition module, an S-band signal tracking module, an S-band remote control signal processing module, an S-band ranging signal processing module, an S-band telemetry data framing module, and a digital-to-analog converter (DAC2); among which... The analog-to-digital converter ADC2 converts the S-band baseband signal from analog to digital and sends it to the S-band anti-interference module. The S-band anti-interference module performs FFT operation on the digital signal and sends the FFT data to the S-band FFT module. The S-band FFT module performs IFFT transformation on the FFT data to obtain the anti-interference digital baseband signal, which is then output to the S-band acquisition module. The S-band acquisition module performs acquisition processing on the digital baseband signal after anti-interference, obtains the acquisition processing result, and sends it to the S-band signal tracking module. The S-band signal tracking module performs frame synchronization on the acquisition and processing results, decodes the remote control signal and ranging tone, sends the remote control signal to the S-band remote control signal processing module, and sends the ranging tone to the S-band ranging signal processing module. The S-band remote control signal processing module outputs a remote control data stream and a corresponding remote control clock based on the remote control signal. The S-band ranging signal processing module forwards the ranging tone to the S-band telemetry data framing module. The S-band telemetry data framing module modulates the ranging tone and the S-band telemetry signal sent by the host computer to generate a downlink baseband signal and outputs the modulated S-band baseband signal.

7. The S / C band space-ground integrated telemetry and control terminal according to claim 6, characterized in that: The capture process specifically includes: A regenerated carrier is generated to downconvert the interfered digital baseband signal, thus completing carrier stripping. Perform correlation operations on the data group codes after carrier stripping, and then accumulate them; Perform an FFT on the accumulated data, and then perform a detection and judgment on the FFT result; Capture the data based on the detection and judgment results, and output the capture processing results.

8. The S / C band space-ground integrated telemetry and control terminal according to claim 6, characterized in that: The acquisition processing results include the pseudocode phase of the spread spectrum signal, a rough estimate of the carrier Doppler frequency shift, and the acquisition status.

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