Research On Waveform Design And Receiving Technology Of Radar Embedded Communication

Radar-Embedded Communication(REC)is a new type of concealed communication method that embeds communication signals in radar backscattered echoes.Compared with the traditional concealed communication method,REC has superior concealment performance and has very broad application prospects in military and civilian fields.This paper mainly studies REC technology from four aspects:performance index evaluation,low-complexity communication waveform design,REC receiver design based on deep learning,and REC technology verification.The main work is as follows:(1)Based on the REC communication waveform performance analysis method of processing gain,this paper theoretically derives the processing gain of the intercepting receiver of the three traditional communication waveforms: Dominant Projection(DP),Shaped Dominant Projection(SDP)and Shaped Water Filling(SWF),and analyzes the Low Probability of Intercept(LPI)performance of the three communication waveforms.This paper presents a performance evaluation index that can unify communication reliability and LPI performance——processing gain advantage,which can evaluate the comprehensive performance of REC communication waveforms.Then it is verified by simulation,and the simulation results are basically consistent with the theoretical analysis.In addition,when considering communication reliability performance priority,LPI performance priority,and comprehensive performance priority,this paper simulates and analyzes the symbol error rate(SER)of DP,SDP,and SWF communication waveforms,and provides a reference for the selection of communication waveform types and parameters under different priorities.Finally,the performances of DP,SDP and SWF are summarized and compared.(2)Based on the SWF waveform generation algorithm with excellent comprehensive performance,this paper proposes an Extraction Shaped Water-Filling(ESWF)waveform generation algorithm with low time calculation complexity.Compared with the traditional DP and SDP waveform generation algorithms,it can reduce the time calculation complexity by at least 0.5K times(K is the number of communication waveform sets,generally selected as 4 or 8),and compared with the SWF waveform generation algorithm,it can reduce the time calculation complexity by at least 1.5K times.Secondly,this paper also conducts theoretical and simulation analysis on the communication reliability performance and LPI performance of the ESWF waveform.The results show that the reliability of the ESWF waveform is slightly reduced,but when the waveform parameters are selected reasonably,the ESWF waveform has better LPI performance and comprehensive performance.In addition,when considering communication reliability performance priority,LPI performance priority and comprehensive performance priority,this paper simulates and analyzes the SER of the four communication waveforms of DP,SDP,SWF and ESWF,and provides a new reference for the selection of communication waveform types and parameters under different priorities.Finally,the performance of DP,SDP,SWF and ESWF communication waveforms is comprehensively summarized and compared,which provides a more comprehensive basis for the selection of communication waveforms.(3)Based on Convolutional Neural Networks(CNN),this paper proposes a new REC cooperative receiver——CNN receiver.The receiving performance of the CNN receiver is simulated and analyzed,and compared with the traditional REC cooperative receiver.The results show that the CNN receiver has a greater performance improvement than the traditional REC cooperative receiver.In addition,when the cooperative receiver uses a CNN receiver,this article simulates the SER of the four communication waveforms of DP,SDP,SWF and ESWF,which provides a new reference for the selection of waveform types and parameters under different priority conditions.Finally,under the condition of using CNN receiver for communication reception,the performance of DP,SDP,SWF and ESWF communication waveforms is summarized,which provides a new basis for the selection of communication waveforms.(4)This paper develops a set of REC verification system based on the Universal Software Radio Peripheral(USRP)hardware platform and Laboratory Virtual Instrumentation Engineering Workbench(Lab VIEW)software,and selects the corresponding communication waveforms under different priorities to test the reliability and concealment performance of the system.The test results show that,compared with the simulation performance,the system has a certain reliability performance loss,but it is within the controllable range.This system can maintain a certain degree of communication reliability while maintaining concealment characteristics,which preliminarily verifies the feasibility of REC and lays a foundation for REC to move from theory to reality.