Research On Signal Deisgn And Processing Method For Integration Of Radar And Communication

Recently,the integrated design of radar and communication has become an intensive research area of radio technology,which can effectively solve the problems of multi-functional integration of electronic equipment and spectrum scarcity.The integration of radar and communication has a great practical value and application prospect in military and civil field.This thesis focuses on the signal design of integration of radar and communication,and a brief summary is given as follows:1)The integrated stepped frequency minimum shift keying(Stepped-MSK)signal that combines stepped frequency(SF)and minimum shift keying(MSK)modulation is proposed.From the perspective of ambiguity function,the detection performance for Stepped-MSK is studied.To alleviate the high sidelobes of zero doppler slice caused by the induced communication bits,a method of decreasing the data rate is utilized.Also,the demodulation framework of Stepped-MSK is designed and the bit error rate formula is derived.Simulation results verify that Stepped-MSK is a feasible integrated signal.2)The integrated signal design based on Dual-Function Radar-Communication(DFRC)system is investigated.Transmit beamforming technique and information-embedding method of DFRC system are mainly discussed.The information-embedding methods for DFRC system are summarized,and a method supporting multi-user and omni-directional communication is proposed.In addition,a scheme of DFRC system based on Directional Modulation(DM)is designed,which improves the performance of anti-interception for the DFRC system by minimizing the differences between beam weight vectors.Simulation results verify the effectiveness and feasibility of the proposed scheme.3)The integrated signal design based on multiple-input and multiple-output(MIMO)radar is studied,and two information-embedding methods named phase modulation and waveform permutation are discussed in detail.The method of phase modulation utilizes the waveform diversity gain of MIMO radar,which realizes communication function by embedding different phases in orthogonal waveforms.Because the embedded phases are independent of the communication azimuth,phase modulation is suitable for the broadcast scenario.While the method of waveform permutation transmits the information through changing the order of orthogonal waveforms.To solve the problem of phase ambiguity caused by the periodicity of array steering vectors,a method of phase compensation is proposed.Because the numerical value of the compensated phase is a function of communication azimuth,waveform permutation is appropriate in the secure communication scenario.4)The integrated signal design based on the sparse antenna selection array is studied,and the applications of the sparse antenna selection array in the DFRC system and MIMO radar are mainly investigated.For the DFRC system,the introduction of the binary antenna selection vector results in the design of beam weight vectors becoming a complex combinatorial optimization problem.The sequential convex programming(SCP)method is proposed to linearize and iteratively approximate the problem,so as to find a better solution that meets the requirement.For the MIMO radar,an additional degree of freedom(Do F)is offered by the reconfigurability of the sparse antenna selection array.Different array configurations are able to represent the various symbols,which can be utilized to embed the information into the radar emission.The combination of sparse antenna selection array and waveform permutation is proposed,which can significantly increase the data rate and improve the performance of demodulation.