Space-based intelligent electromagnetic spectrum sensing system

Abstract

The invention discloses a space-based intelligent electromagnetic spectrum sensing system which comprises a spectrum signal monitoring sensing front end, a satellite-borne intelligent heterogeneous computing platform, a satellite-borne operating system, a high-speed broadband electromagnetic signal processing algorithm and a visualization module. The spectrum signal monitoring and sensing front end is realized based on a multi-band antenna group, provides earth electromagnetic space real-time electromagnetic spectrum monitoring data, and sends the data to the satellite-borne intelligent heterogeneous computing platform; the satellite-borne intelligent heterogeneous computing platform provides satellite-borne intelligent computing power; the satellite-borne operating system runs on the satellite-borne intelligent heterogeneous computing platform, and is combined with satellite-borne applications of a redundancy technology, a virtualization technology and a check point technology, so that the reliability and the fault-tolerant capability are improved, and full-life-cycle management of satellite-borne application programs is provided; and the high-speed broadband electromagnetic signal processing algorithm and visualization module realizes multi-phase filtering channelized receiving, division and parameter estimation of high-speed data based on an unsupervised clustering algorithm and a time-frequency difference positioning technology, obtains signal parameter description words and realizes visual description.

Description

Technical Field

[0001] The present invention belongs to the technical field of on-board applications of intelligent computing, and in particular relates to a space-based intelligent electromagnetic spectrum sensing system. Background Art

[0002] As an important part of the earth's space, electromagnetic space has become the sixth dimension after land, sea, air, space and network, and runs through the other five dimensions. The efficient use of electromagnetic spectrum resources is of strategic significance to economic development and scientific and technological progress. However, with the explosive growth of the number of electromagnetic devices in the world, the electromagnetic space has become more and more complex. At present, the monitoring of the electromagnetic spectrum mainly relies on land-based platforms, but due to the limitation of line of sight, it is difficult to meet the needs of wide-area coverage. In addition, in the face of massive electromagnetic data, the existing land-based system lacks intelligent and efficient data processing capabilities, and a more intelligent and global spectrum management solution is urgently needed.

[0003] Space-based monitoring technology has become an ideal choice for meeting global spectrum monitoring needs due to its wide coverage, strong monitoring capabilities and high-altitude viewing angle. At the same time, traditional space-based spectrum monitoring equipment still faces many technical bottlenecks in the face of increasingly complex electromagnetic environments, including how to achieve wide-area multi-band, full-coverage high-sensitivity signal monitoring, how to perform intelligent and efficient data analysis when processing a large number of electromagnetic signals, and how to achieve the best balance between real-time and accuracy to support spectrum management and decision-making in dynamic electromagnetic environments.

[0004] To overcome these challenges, current technological innovation is gradually turning to combining artificial intelligence with space-based monitoring technology, breaking through the limitations of traditional spectrum monitoring through intelligent algorithms and heterogeneous computing platforms. Intelligent analysis significantly improves the efficiency and accuracy of spectrum management, and the global coverage and highly automated characteristics of space-based platforms make them a key path to solving future electromagnetic spectrum management problems. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the prior art and propose a space-based intelligent electromagnetic spectrum sensing system.

[0006] In order to achieve the above-mentioned object, the present invention provides a space-based intelligent electromagnetic spectrum perception system, comprising: a spectrum signal monitoring and perception front end, a satellite-borne intelligent heterogeneous computing platform, a satellite-borne operating system, and a high-speed broadband electromagnetic signal processing algorithm and visualization module;

[0007] The spectrum signal monitoring and sensing front end is implemented based on a multi-band antenna group, a radio frequency front end and an electromagnetic signal processing FPGA, and is used to provide real-time electromagnetic spectrum monitoring data of the earth's electromagnetic space and send it to the onboard intelligent heterogeneous computing platform for processing;

[0008] The onboard intelligent heterogeneous computing platform is used to provide onboard intelligent computing power;

[0009] The onboard operating system runs on an onboard intelligent heterogeneous computing platform and combines the onboard application of redundancy technology, virtualization technology and checkpoint technology to improve reliability and fault tolerance in dealing with space radiation environment, and also to provide full life cycle management of onboard applications;

[0010] The high-speed broadband electromagnetic signal processing algorithm and visualization module are used to realize multi-phase filtering channelized reception, division and parameter estimation of high-speed data based on unsupervised clustering algorithm and time-frequency difference positioning technology, obtain signal parameter description words, and realize visualization description.

[0011] Preferably, the multi-band antenna group includes: an omnidirectional antenna, a horn antenna, a phased array antenna and a parabolic antenna; wherein,

[0012] The omnidirectional antenna is responsible for VHF, UHF and L bands;

[0013] The horn antenna is responsible for the Ku and Ka bands;

[0014] The phased array antenna is responsible for L, S and C frequency bands;

[0015] The parabolic antenna is responsible for S, C and X bands.

[0016] Preferably, the processing process of the RF front end includes:

[0017] The received signal is power amplified and passed through a down-converter and anti-aliasing filter to obtain a baseband processing signal. The multi-channel baseband processing signal is then dynamically digitized and processed in parallel through a high-speed analog-to-digital conversion chip to complete the serial-to-parallel conversion and narrowband division of the data, thereby achieving signal speed reduction.

[0018] Preferably, the processing process of the electromagnetic spectrum signal processing FPGA includes:

[0019] Energy accumulation in the time-frequency domain is performed within the channel, adaptive constant false alarm detection is set, real-time spectrum analysis of the arrival time and signal amplitude of the measurement signal is performed, parameters such as the instantaneous carrier frequency and bandwidth of the signal are estimated, and signal parameter description words are generated and transmitted to the onboard intelligent heterogeneous computing platform.

[0020] Preferably, the onboard intelligent heterogeneous computing platform adopts a heterogeneous computing architecture based on CPU, GPU and FPGA. The GPU serves as the main processor and is responsible for real-time aliasing signal separation and deinterlacing processing, blind source separation, direction of arrival detection, passive positioning and electromagnetic spectrum perception mapping; the FPGA is responsible for data transmission between modules, parameter estimation processing and precise process control.

[0021] Preferably, the processing of the onboard operating system includes:

[0022] A three-mode redundancy mechanism with dynamic refresh is implemented at the system layer. At the application layer, fault recovery of onboard applications is realized based on virtualization technology and checkpoints. Based on the intelligent application management framework, the expansion of onboard applications is supported. Based on container technology, a lightweight and isolated operating environment is provided to realize autonomous installation, startup, update, uninstallation, restart, stop, status monitoring and fault tolerance of onboard application software.

[0023] Preferably, the processing process of the high-speed broadband electromagnetic signal processing algorithm and visualization module includes:

[0024] Deploy unsupervised clustering algorithms to dilute the density of mixed complex signals; apply fractal dimension and high-order cumulants to extract intra-pulse modulation features of signals, and fuse inter-pulse features to perform blind source separation of signals;

[0025] The electromagnetic waves are sorted according to the RF signal frequencies collected by the spectrum signal monitoring and sensing front end to complete the electromagnetic spectrum mapping. According to the electromagnetic signal quantity, the spatial spectrum estimation technology, multiple signal classification or rotational invariant subspace decomposition is selected to estimate the direction of multiple signal sources arriving at the same time;

[0026] Use time-frequency difference positioning technology to coordinate and match cluster receiving signals, compare the arrival time and arrival frequency values ​​of different satellites and transmission sources, and calculate the location of the transmission source;

[0027] The lateral cross positioning method is used to measure DOA of multiple station radiation sources, match time-frequency information, eliminate false positioning points, and solve the three-dimensional position of multiple target radiation sources.

[0028] Compared with the prior art, the advantages of the present invention are:

[0029] 1. Space deployment of highly reliable AI platforms and fault-tolerant technologies

[0030] Artificial intelligence technology mainly uses GPU to provide computing power. General-purpose GPU is easily affected by the space radiation environment, and the energy source of spacecraft is limited. How to balance system reliability, computing efficiency and power consumption is a major technical difficulty to be solved when deploying artificial intelligence technology in the space environment. The present invention develops a satellite-borne intelligent heterogeneous computing platform, designs a highly reliable satellite-borne operating system for intelligent computing, improves the traditional triple-mode redundancy technology, designs a dynamic refresh hybrid triple-mode redundancy mechanism, improves the CRIU checkpoint solution based on virtualization technology, sets dynamic refresh frequency rules, rollback and verification mechanisms, and further enhances the reliability of the system. It is a new attempt to integrate virtualization technology with checkpoint technology (CRIU) on-board applications.

[0031] 2. Multi-band, multi-system, multi-target recognition and classification technology

[0032] The present invention is aimed at complex electromagnetic scenes with numerous radiation source models, dense electromagnetic spectrum signals, and similar or overlapping signal parameters. A multi-band antenna group is designed to complete signal acquisition, full digital channelization is adopted to perform multi-parameter real-time detection, and signal sorting and identification algorithms are deployed on the intelligent computing platform, which efficiently and accurately realizes the detection and stable sorting and identification of radiation source signals of multiple systems and multiple targets in complex electromagnetic environments.

[0033] 3. Multi-station electromagnetic spectrum data correlation analysis and false positioning elimination

[0034] If the deviation of multi-station electromagnetic spectrum data parameter fusion exceeds a certain limit, it will affect the signal perception process. The present invention obtains IQ data, signal characteristics, positioning data, occupancy rate and other information, and then indexes and traces the spectrum data, thereby solving the problem of multi-station electromagnetic spectrum data parameter fusion deviation affecting the signal perception process. At the same time, it combines multi-station information flow to solve the "increase in batches" problem and eliminates false positioning to achieve the established indicators.

[0035] 4. Multi-dimensional spectrum situation awareness and visualization analysis of time, space and frequency

[0036] The present invention develops time-space-frequency multi-dimensional spectrum situation awareness and visualization analysis for space-based intelligent spectrum monitoring, optimizes data processing and analysis algorithms, and deploys intelligent computing platform hardware to achieve rapid processing and effective utilization of massive data. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is the structure diagram of the space-based intelligent electromagnetic spectrum perception system

[0038] Figure 2(a) is a structural diagram of the appearance of the space-based intelligent electromagnetic spectrum perception system;

[0039] Figure 2(b) is an omnidirectional antenna of a multi-band antenna group, Figure 2(c) is a horn antenna, Figure 2(d) is a parabolic antenna, and Figure 2(e) is a phased array antenna;

[0040] Figure 3 It is the system structure diagram;

[0041] Figure 4 This is the hardware diagram of the onboard intelligent computing platform;

[0042] Figure 5 It is a hierarchical diagram of the onboard intelligent computing operating system;

[0043] Figure 6 It is a flowchart of the positioning method;

[0044] Figure 7 It is a schematic diagram of the RF front-end hardware architecture. DETAILED DESCRIPTION

[0045] Based on the above background, the space-based intelligent electromagnetic spectrum perception system proposed in this invention aims to build a space-based platform with wide-area coverage, intelligent processing and real-time response capabilities through innovative intelligent perception and analysis technologies, which is different from the current traditional ground-based monitoring platform. The system combines the on-board intelligent heterogeneous computing platform, the spectrum signal perception front end, the virtualized operating system and the advanced high-speed broadband electromagnetic signal processing algorithm, breaking the limitations of traditional monitoring methods, providing a solution to the current situation of increasingly complex electromagnetic space and chaotic electromagnetic space spectrum order, and providing a new intelligent solution for electromagnetic space spectrum management.

[0046] The system aims at fully intelligent electromagnetic space situation monitoring, relies on onboard intelligent heterogeneous computing technology, monitors and locates radio signals from satellite orbit, uses orbital altitude to conduct wide-range spectrum monitoring, and optimizes antenna design to improve signal reception sensitivity and coverage. Intelligent processing methods provide powerful data analysis capabilities, and global distribution and spectrum situation are obtained from local (point, line) data, helping to accurately and efficiently realize electromagnetic space situation assessment and visualization.

[0047] like Figure 1 As shown in Figure 2, the system is mainly divided into four hardware and software parts: the spectrum signal monitoring perception front end provides real-time electromagnetic spectrum data of the earth's electromagnetic space; the onboard intelligent heterogeneous computing platform provides high-performance and high-reliability onboard intelligent computing power to meet the massive digital signal processing required for perception; the highly reliable intelligent onboard operating system improves the system's fault tolerance in dealing with the space radiation environment; the digital / analog electromagnetic spectrum signal processing and visualization module realizes multi-phase filtering channelized reception, division, and parameter estimation of high-speed data, obtains signal parameter description words, realizes signal radiation source positioning and identification, and realizes visual description. The appearance of the payload is shown in Figure 2(a).

[0048] The technical solution of the present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0049] Example

[0050] An embodiment of the present invention provides a space-based intelligent electromagnetic spectrum perception system.

[0051] The design of the space-based intelligent electromagnetic spectrum perception system must meet multiple constraints for normal operation in a space environment. In terms of performance, the system must have frequency detection capabilities in the VHF, UHF, L, S, C, X, Ku, and Ka bands, a receiving sensitivity of -100dBm, a sampling rate of 61.44Msps, 10 receiving channels, and a 20dBi antenna gain; the radiation environment index is 23Kard (when running) and 45Kard (when shut down); in terms of power requirements, the system operation must be supported by a 28V power supply, and the total power consumption does not exceed 30W; in terms of appearance design, the system volume is 300*200*200 mm. In terms of reliability indicators, the system design life is not less than 5 years, the assessment life is not less than 3 years, the radiation dose is greater than or equal to 10Kard (Si) (5 years), and the reliability at the end of the 3-year life must be higher than 0.99. The system has a single-particle flip-resistant design.

[0052] In terms of functions, it can overcome the current electromagnetic spectrum monitoring platform's difficulty in meeting wide-area requirements due to the limitation of line-of-sight. At the same time, in the face of massive electromagnetic space data, it uses intelligent processing methods to provide powerful data analysis capabilities, obtains global distribution and spectrum situation from local (point, line) data, effectively supplements other data sources, and helps to accurately and efficiently realize electromagnetic space situation assessment and visualization. Maintain the order and safety of airwaves, ensure the normal operation of various radio services, and enhance intelligent, refined, and unmanned spectrum management capabilities.

[0053] In order to achieve the above objectives, the present invention completes the design of a space-based intelligent electromagnetic spectrum perception system, which mainly consists of four components: a satellite-borne intelligent heterogeneous computing platform (GPU+CPU+FPGA), a spectrum signal monitoring and perception front-end, a highly reliable intelligent satellite-borne high-energy computing operating system based on redundancy technology and virtualization technology, and a high-speed broadband electromagnetic signal processing algorithm and a visualization module.

[0054] 1. RF front-end and signal processing platform

[0055] Optimize antenna design to improve the sensitivity and coverage of signal reception. The multi-band antenna group is responsible for receiving multi-band signals, among which the omnidirectional antenna is responsible for VHF, UHF, and L bands, as shown in Figure 2(b); the horn antenna is responsible for Ku and Ka bands, as shown in Figure 2(c); the parabolic antenna is responsible for S, C, and X bands, as shown in Figure 2(d); and the phased array antenna is responsible for L, S, and C bands, as shown in Figure 2(e).

[0056] The spectrum signal sensing front end uses a multi-band antenna group to design a power amplifier for the received signal, and obtains the baseband processing signal after down-conversion processing and anti-aliasing filter, such as Figure 3 As shown in the system block diagram.

[0057] In the spectrum analysis part, a 61.44MSPS high-speed analog-to-digital conversion chip is used, combined with FPGA to realize a high-performance software radio signal acquisition system. The RF front-end hardware architecture is as follows: Figure 7 As shown, the collected signals are sent to the FPGA for multi-channel dynamic digitization and parallel data processing, completing the serial-to-parallel conversion and narrowband division of the data to achieve signal speed reduction.

[0058] FPGA performs signal detection and spectrum parameter measurement in real time, accumulates time-frequency domain energy in the channel, and sets adaptive constant false alarm detection. It measures the time domain parameters such as the arrival time (TOA) and signal amplitude (AP) of the signal, performs real-time spectrum analysis, and estimates parameters such as the instantaneous carrier frequency and bandwidth of the signal. It integrates the time-frequency parameter measurement results, generates a signal parameter description word, and transmits it to the hardware intelligent platform for the next step of processing.

[0059] 2. Onboard intelligent heterogeneous computing platform

[0060] In order to meet the computing power requirements of large-scale digital signal processing, independently designed and implemented on-board intelligent computing components are used, adopting a heterogeneous computing architecture that combines CPU, GPU and FPGA. The intelligent computing part uses NVIDIA Jetson AGXXavier + on-board Linux operating system. The GPU is the main processor, responsible for real-time and high-speed data processing. Its powerful parallel processing performance can improve the real-time processing capability of the system. FPGA is responsible for complex data transmission, conversion processing and precise process control between modules. The system can provide 11TFLOPS floating-point computing power and 32TOPS integer on-board computing power. The computing power and power consumption of the device meet the requirements for data processing. It has passed reliability experimental tests and can meet the on-orbit operation standards. The overall hardware design block diagram is shown below. Figure 4 shown.

[0061] 3. Highly reliable intelligent onboard high-energy computing operating system based on redundancy and virtualization technologies

[0062] In response to the requirements of high-performance and high-reliability satellite missions, based on the above-mentioned intelligent computing hardware platform, this payload will build a high-performance and high-reliability satellite operating system for satellite-based intelligent computing, and port it to the satellite-based heterogeneous intelligent computing platform. It will expand the software structure based on multi-core processors, support the expansion of intelligent applications, use virtualization technology for application isolation, further improve system reliability, design and implement an autonomous management program for satellite service software, and propose an on-board application management solution based on container technology. Container technology provides a lightweight and isolated operating environment to achieve autonomous installation, startup, update, uninstallation and stopping of satellite-based applications, while monitoring application status to improve system management efficiency and scalability. It realizes the full life cycle management of satellite-based applications. It combines virtualization technology and CRIU technology, and makes improvements to add dynamic checkpoint rules and verification rollback mechanisms to further improve system reliability. The operating system hierarchy is as follows: Figure 5 shown.

[0063] 4. High-speed broadband electromagnetic signal processing algorithm and visualization module

[0064] The intelligent platform deploys an unsupervised clustering algorithm to dilute the density of mixed complex signals; it applies fractal dimension and high-order cumulants to extract the intra-pulse modulation features of the signal, and fuses the inter-pulse features to perform blind source separation of the signal. The satellite platform can collect radio frequency signals in an area with a diameter of hundreds of kilometers, and quickly sort the electromagnetic waves according to the frequency to complete the electromagnetic spectrum mapping. According to the amount of electromagnetic signals, the spatial spectrum estimation technology multiple signal classification (MUSIC) or rotational invariant subspace decomposition (ESPRIT) is selected for direction estimation (DOA), which effectively estimates the directions of multiple signal sources arriving at the same time.

[0065] Use time-frequency difference positioning technology to coordinately match cluster receiving signals, compare the arrival time (TOA) and arrival frequency (FOA) values ​​of different satellites and transmission sources, and calculate the location of the transmission source; use the lateral cross positioning method to measure DOA with multiple station radiation sources, match time-frequency information, eliminate false positioning points, and solve the three-dimensional position of multiple target radiation sources. The process is as follows: Figure 6 shown.

[0066] Summary:

[0067] The present invention can achieve wide-area, real-time electromagnetic spectrum monitoring and situational awareness on satellite platforms through the deep combination of intelligent algorithms and heterogeneous computing technologies. In particular, the collaborative computing of onboard GPU, CPU and FPGA overcomes the reliability and computing power limitations of traditional equipment in space radiation environments, enabling it to efficiently process massive amounts of electromagnetic signal data and provide real-time, accurate spectrum situation analysis and visualization. This innovative solution provides strong technical support for spectrum management and electromagnetic space security in complex electromagnetic environments, greatly enhancing unmanned, intelligent and refined spectrum management capabilities. Ensure the safe and efficient use of limited Earth space spectrum resources.

[0068] With the help of the above-mentioned hardware platform design and related algorithm improvements, through deep integration in multiple dimensions such as computing architecture, system software, signal recognition, and data processing, the present invention innovatively realizes multi-band signal monitoring, real-time processing of massive data, accurate signal detection and parameter estimation, satellite-borne autonomous operation and fault-tolerant management, improves the electromagnetic spectrum monitoring mechanism, maintains the order of electromagnetic spectrum resources, further promotes the frontier development of space-based intelligent electromagnetic spectrum perception technology, and provides strong technical support for future electromagnetic space management.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention is described in detail with reference to the embodiments, it should be understood by those skilled in the art that any modification or equivalent replacement of the technical solutions of the present invention does not depart from the spirit and scope of the technical solutions of the present invention and should be included in the scope of the claims of the present invention.

Claims

1. A space-based intelligent electromagnetic spectrum sensing system, characterized in that: include: Spectrum signal monitoring and perception front end, onboard intelligent heterogeneous computing platform, onboard operating system, and high-speed broadband electromagnetic signal processing algorithm and visualization module; The spectrum signal monitoring and sensing front end is implemented based on a multi-band antenna group, a radio frequency front end and a high-speed broadband electromagnetic signal processing FPGA, and is used to provide real-time electromagnetic spectrum monitoring data of the earth's electromagnetic space and send it to the onboard intelligent heterogeneous computing platform for processing; The onboard intelligent heterogeneous computing platform is used to provide onboard intelligent computing power; The onboard operating system runs on an onboard intelligent heterogeneous computing platform and combines the onboard application of redundancy technology, virtualization technology and checkpoint technology to improve reliability and fault tolerance in dealing with space radiation environment, and also to provide full life cycle management of onboard applications; The high-speed broadband electromagnetic signal processing algorithm and visualization module are used to realize multi-phase filtering channelized reception, division and parameter estimation of high-speed data based on unsupervised clustering algorithm and time-frequency difference positioning technology, obtain signal parameter description words, and realize visualization description.

2. The space-based intelligent electromagnetic spectrum sensing system according to claim 1 is characterized in that: The multi-band antenna group includes: an omnidirectional antenna, a horn antenna, a phased array antenna and a parabolic antenna; wherein, The omnidirectional antenna is responsible for VHF, UHF and L bands; The horn antenna is responsible for the Ku and Ka bands; The phased array antenna is responsible for L, S and C frequency bands; The parabolic antenna is responsible for S, C and X bands.

3. The space-based intelligent electromagnetic spectrum sensing system according to claim 1 is characterized in that: The processing process of the RF front end includes: The received signal is power amplified and passed through a down-converter and anti-aliasing filter to obtain a baseband processing signal. The multi-channel baseband processing signal is then dynamically digitized and processed in parallel through a high-speed analog-to-digital conversion chip to complete the serial-to-parallel conversion and narrowband division of the data, thereby achieving signal speed reduction.

4. The space-based intelligent electromagnetic spectrum sensing system according to claim 1 is characterized in that: The processing process of the electromagnetic signal processing FPGA includes: Energy accumulation in the time-frequency domain is performed within the channel, adaptive constant false alarm detection is set, real-time spectrum analysis of the arrival time and signal amplitude of the measurement signal is performed, parameters such as the instantaneous carrier frequency and bandwidth of the signal are estimated, and signal parameter description words are generated and transmitted to the onboard intelligent heterogeneous computing platform.

5. The space-based intelligent electromagnetic spectrum sensing system according to claim 1 is characterized in that: The onboard intelligent heterogeneous computing platform adopts a heterogeneous computing architecture based on CPU, GPU and FPGA. The GPU is the main processor, responsible for real-time aliasing signal separation and deinterlacing, blind source separation, direction of arrival detection, passive positioning and electromagnetic spectrum perception mapping; the FPGA is responsible for data transmission between modules, parameter estimation processing and precise process control.

6. The space-based intelligent electromagnetic spectrum sensing system according to claim 1 is characterized in that: The processing of the onboard operating system includes: A three-mode redundancy mechanism with dynamic refresh is implemented at the system layer. At the application layer, fault recovery of onboard applications is realized based on virtualization technology and checkpoints. Based on the intelligent application management framework, the expansion of onboard applications is supported. Based on container technology, a lightweight and isolated operating environment is provided to realize autonomous installation, startup, update, uninstallation, restart, stop, status monitoring and fault tolerance of onboard application software.

7. The space-based intelligent electromagnetic spectrum sensing system according to claim 1 is characterized in that: The processing process of the high-speed broadband electromagnetic signal processing algorithm and visualization module includes: Deploy unsupervised clustering algorithms to dilute the density of mixed complex signals; apply fractal dimension and high-order cumulants to extract intra-pulse modulation features of signals, and fuse inter-pulse features to perform blind source separation of signals; According to the RF signal frequency collected by the spectrum signal monitoring and sensing front end, the electromagnetic waves are sorted to complete the electromagnetic spectrum mapping. According to the electromagnetic signal quantity, the spatial spectrum estimation technology, multiple signal classification or rotational invariant subspace decomposition is selected to estimate the direction of multiple signal sources arriving at the same time; Use time-frequency difference positioning technology to coordinate and match cluster receiving signals, compare the arrival time and arrival frequency values ​​of different satellites and transmission sources, and calculate the location of the transmission source; The lateral cross positioning method is used to measure DOA of multiple station radiation sources, match time-frequency information, eliminate false positioning points, and solve the three-dimensional position of multiple target radiation sources.

Images