A satellite communication channel compatibility analysis and simulation system

Abstract

The present invention relates to the field of satellite communication channel compatibility analysis and simulation, and specifically to a satellite communication channel compatibility analysis and simulation system. The solution includes a simulation software subsystem and a semi-physical simulation subsystem. The present invention uses the simulation software subsystem to construct the application scenario of the satellite and complete functions such as constellation construction and orbit calculation; uses the semi-physical subsystem to complete link-level signal simulation, generate and receive analysis baseband signals, simulate the entire signal generation, signal transmission and signal reception process in the actual satellite link, and realize the simulation of the constellation system from the scenario level to the signal level. At the same time, the present invention enables the semi-physical simulation subsystem and the simulation software subsystem to work together through collaborative simulation. The collaborative simulation is mainly when the channel quality is very good or very poor. The semi-physical simulation subsystem skips the simulation process at the current moment and directly enters the simulation at the next moment, which greatly improves the simulation calculation efficiency. The present invention is suitable for satellite communication channel compatibility analysis and simulation.

Description

Technical Field

[0001] The present invention relates to the field of satellite communication channel compatibility analysis and simulation, and in particular to a satellite communication channel compatibility analysis and simulation system. Background Art

[0002] With the deployment of a large number of low-orbit satellite constellations, space orbits and spectrum resources are becoming increasingly congested. Current research on satellite issues can be divided into two main aspects: constellation configuration design and frequency compatibility research. In the process of frequency compatibility research, a detailed frequency interference model is often established and verified using a verification simulation system to evaluate the possible interference that may be generated by satellite systems when sharing spectrum resources, including co-channel interference, adjacent-channel interference, and cross-interference. Connecting physical objects such as communication links and communication signals to digital simulations is the core technology of satellite communication technology verification simulation systems. It mainly includes simulation software systems and simulation equipment systems, simulates satellite spatial relationships, propagation models, etc., simulates the communication process of satellite systems, and makes the simulation results closer to actual application conditions.

[0003] Due to limitations such as bandwidth and hardware computing power, hardware-in-the-loop simulation systems are slower than software-based simulation systems. Furthermore, during signal processing, demodulation and decoding typically take longer than modulation and coding. Furthermore, in actual satellite link interference, interference only occurs for a very short period of time. If hardware-in-the-loop simulation systems performed demodulation and decoding at every simulation moment, this would significantly increase system computing resources and reduce simulation efficiency. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a satellite communication channel compatibility analysis simulation system to improve the simulation calculation efficiency.

[0005] The present invention adopts the following technical solutions to achieve the above-mentioned purpose. The present invention provides a satellite communication channel compatibility analysis simulation system, comprising:

[0006] It includes a simulation software subsystem and a semi-physical simulation subsystem, wherein the semi-physical simulation subsystem includes a signal generating device, a signal transmission coupling device and a signal receiving device;

[0007] Build simulation scenarios in the simulation software subsystem, establish constellations using six element numbers and orbital configurations, set ground station parameters and antenna models, and configure simulation signal parameters;

[0008] The semi-physical simulation subsystem receives the signal parameters sent by the simulation software subsystem and generates radio frequency signals of the disturbed signal and the interfering signal in the signal generating device;

[0009] The simulation software subsystem begins simulation. Based on the satellite orbit model, spatial attenuation model, and tracking strategy, it calculates the signal and channel states at each simulation moment during satellite operation, including the victim signal power, interference signal power, and noise power, and sends these to the hardware-in-the-loop simulation subsystem.

[0010] The hardware-in-the-loop simulation subsystem receives the signal and channel status at each simulation moment from the simulation software, calculates and distributes them to the digitally controlled attenuators of each device, ensuring that the signal meets the signal strength requirements of the receiver front end in the actual scenario.

[0011] The radio frequency signals of the victim signal and the interference signal are received by the signal transmission coupling device, and the victim signal and the interference signal are respectively formed into a scrambled signal of the victim signal and the interference signal through a digitally controlled attenuator and a combiner inside the signal transmission coupling device;

[0012] The signal receiving module in the signal receiving device receives the RF signal of the scrambled signal, collects and sorts the signal, and then processes it through ADC (Analog-to-Digital Conversion), DDC (Digital Down-Conversion), and filtering to generate the baseband IQ signal of the scrambled signal, which is then transmitted to the server of the semi-physical simulation subsystem.

[0013] The server of the hardware-in-the-loop simulation subsystem receives baseband IQ signals, performs signal synchronization, demodulation, and decoding, obtains the constellation diagram, EVM (Error Vector Magnitude) value, bit error rate, and signal level of the disturbed link or interfering link signal, and generates simulation results.

[0014] Furthermore, the signal parameters include signal system, signal modulation mode, signal coding mode, frequency, bandwidth and ACM strategy. The signal system includes LTE, 5G, DVB, Starlink and microwave communication. The signal modulation mode includes BPSK, π / 2-BPSK, QPSK, 8PSK, 16QAM, 16APSK, 32APSK, 64QAM, 64APSK, 128APSK, 256QAM, 256APSK, AM and CPM. The signal coding mode includes LDPC, VTB and Turbo code.

[0015] Furthermore, the hardware-in-the-loop simulation subsystem and the simulation software subsystem can work together through co-simulation. The co-simulation specifically includes:

[0016] Set the channel state boundary value for each signal system. The channel state boundary value includes the optimal channel state value and the worst channel state value. When the channel state exceeds the optimal channel state value, the signal is received correctly. When the signal quality is lower than the worst signal quality value, the signal cannot be received.

[0017] The channel state of the current link is preliminarily calculated. The hardware-in-the-loop simulation subsystem receives the disturbed signal power, interference signal power, and noise power sent by the simulation software subsystem. If the calculated channel state is greater than the optimal channel state or less than the worst channel state, the signal generation and reception processing flow is not enabled, and the simulation proceeds directly to the next moment.

[0018] Measure the channel status of the current link and compare the measured channel status with the set threshold. If the measured channel status is better than the set optimal threshold, directly return no error and do not enable the signal reception processing process. If the measured channel status is better than the set worst threshold, it indicates that demodulation is impossible. At this time, directly perform simulation at the next moment. When the measured channel status is between the optimal threshold and the worst threshold, start the demodulation and decoding process.

[0019] The beneficial effects of the present invention are:

[0020] The present invention uses a simulation software subsystem to construct satellite application scenarios and complete functions such as constellation construction and orbit calculation, such as low-orbit constellation-to-low-orbit constellation, low-orbit constellation-to-Geosynchronous Orbit (GSO), and low-orbit constellation-to-ground system. The semi-physical subsystem is used to complete link-level signal simulation, generate, receive and analyze baseband signals, and simulate the entire signal generation, signal transmission and signal reception processing flow in actual satellite links, thus realizing the simulation of the constellation system from the scenario level to the signal level.

[0021] This invention designs a collaborative simulation process that enables the hardware-in-the-loop simulation subsystem and the simulation software subsystem to work together without affecting the simulation results. The collaborative simulation primarily involves skipping the simulation process at the current moment and directly moving on to the next moment when channel quality is good or poor. This eliminates the need for the hardware-in-the-loop simulation system to perform demodulation and decoding at every moment, significantly improving simulation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention provides a satellite communication channel compatibility analysis and simulation system structure diagram. DETAILED DESCRIPTION

[0023] To make the objectives, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0024] The present invention provides a satellite communication channel compatibility analysis simulation system. Figure 1 As shown, it includes a simulation software subsystem and a semi-physical simulation subsystem. The simulation software subsystem includes a constellation configuration module, a beam planning module, a link calculation module, an attenuation model module, an orbit calculation module, a satellite tracking strategy module, a signal analysis module and corresponding servers.

[0025] The semi-physical simulation subsystem includes a signal generating device, a signal transmission coupling device and a signal receiving device. The signal generating device includes multiple signal generating modules and corresponding servers, the signal transmission coupling device includes a signal coupling module, and the signal receiving device includes multiple signal receiving modules and corresponding servers.

[0026] In the simulation software subsystem, a simulation scenario is constructed. The constellation is established using six elements and orbital configurations. Ground station parameters and antenna models are set, and simulation signal parameters are configured. Signal parameters include signal system, modulation method, coding method, frequency, bandwidth, and ACM strategy. Signal systems include LTE, 5G, DVB, Starlink, and microwave communication. Modulation methods include BPSK, π / 2-BPSK, QPSK, 8PSK, 16QAM, 16APSK, 32APSK, 64QAM, 64APSK, 128APSK, 256QAM, 256APSK, AM, and CPM. Coding methods include LDPC, VTB, and Turbo codes.

[0027] The semi-physical simulation subsystem receives the signal parameters sent by the simulation software subsystem and generates radio frequency signals of the disturbed signal and the interfering signal in the signal generating device.

[0028] The simulation software subsystem starts the simulation and calculates the signal state and channel state at each simulation moment during the satellite operation based on the satellite orbit model, spatial attenuation model, and satellite tracking strategy, including the disturbed signal power, interference signal power, and noise power, and sends them to the semi-physical simulation subsystem.

[0029] The semi-physical simulation subsystem receives the signal status and channel status at each simulation moment issued by the simulation software, calculates and distributes them to the digitally controlled attenuators of each device, so that the signal meets the signal strength requirements of the receiver front end in the actual scenario.

[0030] The radio frequency signals of the disturbed signal and the interfering signal are received by the signal transmission coupling device. The disturbed signal and the interfering signal are respectively formed into a scrambled signal of the disturbed signal and the interfering signal through a digitally controlled attenuator and a combiner inside the signal transmission coupling device.

[0031] The RF signal of the scrambled signal is received by the signal receiving module in the signal receiving device, and the signal is collected and sorted. Through ADC, DDC and filtering processing, the baseband IQ signal of the scrambled signal is formed and transmitted to the corresponding server.

[0032] The server of the hardware-in-the-loop simulation subsystem receives baseband IQ signals, performs signal synchronization, signal demodulation, and signal decoding, obtains the signal constellation diagram of the disturbed link (interfering link), EVM value, bit error rate of the disturbed link (interfering link), and signal level of the disturbed link (interfering link), and generates simulation results.

[0033] To address the disparity in simulation speed between the hardware-in-the-loop (HIL) simulation subsystem and the simulation software subsystem, the present invention has designed a collaborative simulation process that enables the HIL and simulation software subsystems to work together without affecting the simulation results. Specifically, the primary purpose of collaborative simulation is to enable the HIL simulation subsystem to skip the current simulation moment and directly proceed to the next simulation moment when channel quality is excellent or poor. This eliminates the need for the HIL simulation subsystem to perform demodulation and decoding at every simulation moment.

[0034] Co-simulation specifically includes:

[0035] Set the channel state boundary value for each signal system. The channel state boundary value includes the optimal channel state value and the worst channel state value. When the channel state exceeds the optimal channel state value, it can be received correctly. When the signal quality is lower than the worst signal quality value, it cannot be received at all.

[0036] Preliminary calculation of the channel state Dc of the current link is performed using the hardware-in-the-loop simulation subsystem to receive the victim signal power, interference signal power, and noise power sent by the simulation software subsystem. The channel state Dc of the current link, such as C / N (Carrier-to-Noise Ratio) and C / I (Carrier-to-Interference Ratio), is calculated.

[0037] Calculate the channel state Dc for the current link. If the calculated channel state Dc is greater than the optimal channel state or less than the worst-case channel state, the signal generation and reception processes are disabled. A value significantly greater than or less than the channel state is related to system measurement errors. If the calculated channel state Dc is significantly greater than the optimal channel state, it indicates error-free demodulation. If it is significantly less than the optimal channel state, demodulation is unsuccessful. Simulation then proceeds directly to the next time step.

[0038] Measure the channel state Dt of the current link and compare the measured channel state Dt with the set threshold. If the channel state Dt is better than the set optimal threshold, directly return to no error and do not enable the signal reception processing process. If the channel state Dt is better than the set worst threshold, it indicates that demodulation is impossible. At this time, directly perform simulation at the next moment. When the measured channel state Dt is between the optimal threshold and the worst threshold, start the demodulation and decoding process.

[0039] The foregoing description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Rather, the present invention can be used in various other combinations, modifications, and environments and can be modified within the scope of the concept described herein through the above teachings or techniques or knowledge in the relevant field. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention are intended to be protected by the appended claims.

Claims

1. A satellite communication channel compatibility analysis and simulation system, characterized in that: It includes a simulation software subsystem and a semi-physical simulation subsystem, wherein the semi-physical simulation subsystem includes a signal generating device, a signal transmission coupling device and a signal receiving device; Build simulation scenarios in the simulation software subsystem, establish constellations using six element numbers and orbital configurations, set ground station parameters and antenna models, and configure simulation signal parameters; The semi-physical simulation subsystem receives the signal parameters sent by the simulation software subsystem and generates radio frequency signals of the disturbed signal and the interfering signal in the signal generating device; The simulation software subsystem begins simulation. Based on the satellite orbit model, spatial attenuation model, and tracking strategy, it calculates the signal and channel states at each simulation moment during satellite operation, including the victim signal power, interference signal power, and noise power, and sends these to the hardware-in-the-loop simulation subsystem. The hardware-in-the-loop simulation subsystem receives the signal and channel status at each simulation moment from the simulation software, calculates and distributes them to the digitally controlled attenuators of each device, ensuring that the signal meets the signal strength requirements of the receiver front end in the actual scenario. The radio frequency signals of the victim signal and the interference signal are received by the signal transmission coupling device, and the victim signal and the interference signal are respectively formed into a scrambled signal of the victim signal and the interference signal through a digitally controlled attenuator and a combiner inside the signal transmission coupling device; The signal receiving module in the signal receiving device receives the RF signal of the scrambled signal, collects and sorts the signal, and forms the baseband IQ signal of the scrambled signal through ADC, DDC and filtering processing, and transmits it to the server of the semi-physical simulation subsystem; The server of the hardware-in-the-loop simulation subsystem receives baseband IQ signals, performs signal synchronization, signal demodulation, and signal decoding, obtains the constellation diagram, EVM value, bit error rate, and signal level of the disturbed link or interference link signal, and generates simulation results. The hardware-in-the-loop simulation subsystem and the simulation software subsystem work together through co-simulation. Co-simulation specifically includes: Set the channel state boundary value for each signal system. The channel state boundary value includes the optimal channel state value and the worst channel state value. When the channel state exceeds the optimal channel state value, the signal is received correctly. When the signal quality is lower than the worst signal quality value, the signal cannot be received. The channel state of the current link is preliminarily calculated. The hardware-in-the-loop simulation subsystem receives the disturbed signal power, interference signal power, and noise power sent by the simulation software subsystem. If the calculated channel state is greater than the optimal channel state or less than the worst channel state, the signal generation and reception processing flow is not enabled, and the simulation proceeds directly to the next moment. Measure the channel status of the current link and compare the measured channel status with the set threshold. If the measured channel status is better than the set optimal threshold, directly return to no error, do not enable the signal reception processing process. If the measured channel status is lower than the set worst threshold, it indicates that demodulation is impossible. At this time, directly perform simulation at the next moment. When the measured channel status is between the optimal threshold and the worst threshold, start the demodulation and decoding process.

2. The satellite communication channel compatibility analysis simulation system according to claim 1, characterized in that: The signal parameters include signal system, signal modulation mode, signal coding mode, frequency, bandwidth and ACM strategy. The signal system includes LTE, 5G, DVB, Starlink and microwave communication. The signal modulation mode includes BPSK, π / 2-BPSK, QPSK, 8PSK, 16QAM, 16APSK, 32APSK, 64QAM, 64APSK, 128APSK, 256QAM, 256APSK, AM and CPM. The signal coding mode includes LDPC, VTB and Turbo code.

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