Research On Anti Active Deception Jamming Technology Of Radar Waveform Design

With the understanding of the interference mechanism and the enlightment of waveform diversity and MIMO radar,this thesis proposed to launch designed waveform to counter active deception jamming.By using time lag of echo signal and interference signal,the goal of suppressing interference when radar receives the signal is achieved.The main work is how to design the complex radar signal waveform library with good orthogonality.This dissertation do much research on that the most commonly used large time-bandwidth product of signal,and introduces the chaotic sequences to optimize the orthogonality,and using multi-time coding to improve the complexity of waveform.This dissertation mainly launches the work according to the following arrangement:1.This dissertation firstly introduces the principle of active deception jamming and the flowing of radar signal processing,and then brings forward the idea of resisting active deception jamming through waveform design.2.Increase the number of waveform.It is found that the waveform is relatively simple,and it is not suitable for the anti-jamming method used in this paper through the study of the single modulation signal.Therefore,this paper combines the linear frequency modulation signal with Frank,P1,P2,P3,P4 coding,and the orthogonality and anti-jamming performance are analyzed.It is found that the number of waveforms can be increased and the interference suppression ability can be improved by the combination transform,but the interference signal can not be completely offset.3.Improve the orthogonality of waveform.The property of four kinds of chaotic sequences are analyzed,it is a simple method to generate,the sensitivity to the initial value and the characteristics of the traversal can bring a lot of changes to the chaotic sequence,and each other with good auto-correlation and cross-correlation.By combining chaotic signal with phase coding and frequency coding,the number of waveforms can be increased,and the orthogonality can also be optimized.Based on the analysis of the performance of the interference suppression,the waveform generated by the chaotic sequences has excellent anti-jamming performance.4.Improve the complexity of waveform.In the multi-time coding.the number of phase states can be set independently,and the length of time occupied by different phase states is different in the duration of the whole waveform.In this paper,T1,T2,T3,T4 coding phase sequence,and it's orthogonal characteristics are analyzed.Put forward to quantization modulation of multi-time coding sequences by chaotic sequence,and designed a new waveform;through the analysis of the orthogonality and anti-jamming performance,the waveform design method can effectively suppress active deception jamming.