Waveform Analyze And Optimize Based On HF Communication Coding For MIMO Radar

Multi-input multi-output radar processes signal in multi-channel by using multiple transmit and multiple received antenna.The transmitted waveform ambiguity function reflects range ambiguity and range-clutter-folding,doppler ambiguity and doppler-frequency-aliasing target detection performance.Based on the waveform ambiguity research idea,the paper study a HF communication coding waveform regularity of distribution in unambiguous region under the MIMO radar in depth,and a corresponding waveform design method for improving unambiguous region area is proposed.The research work and innovations of this paper are as follows:(1)Firstly,the paper studies the mathematical properties and the correlation function of GQ(Goutelard Q-ary)orthogonal coding sequence.The paper focus on the analysis of the GQ coding waveforms in range and doppler spectrum regularities of distribution for monocycle and multicycle in unambiguous region.The paper analyzes the unambiguous area of the GQ waveform under SIMO and MIMO radar,and obtains the conclusion that the area of GQ orthogonal waveform under MIMO radar is reduced Z times.So that it can lay of the theoretical foundation for waveform design parameters and optimization ideas for multi-targets detection in the complex environment(2)The paper designs and constructs the OFD-GQ waveform signal to optimize the GQ waveform in unambiguous region under the MIMO radar.Based on the theory and simulation,the results show that the unambiguous region area expand Z times.Building spatial synthesized OFD-GQ signals structure based on the sequential quadratic programming(SQP)algorithm with non-uniform frequency interval optimize method,while the transmitted power beampattern approaches omnidirectionality,The maximum APSL mainlobe peak decreasing amplitude achieved 8.5dB and improved the target detection performance of the GQ waveform under the MIMO radar.Lastly the paper analysed GQ waveforms doppler sensitivity under different waveform structures.The results show that the GQ waveform has strong Doppler sensitivity,which is not conducive to the detection of the high-speed moving target for the unambiguous doppler resolution unit.The peak period interval of the spatial synthesized OFD-GQ waveform is increased.Under the same Doppler shift range,Spatial synthesized OFD-GQ waveform is conducive to improve the performance of the target detection.Finally,compared with the equal interval spatial synthesized OFD-GQ waveform performence,the non-uniform frequency interval optimized waveform structure has poor doppler frequency shift tolerance.