Waveform Design For Continuous Wave Radar And Research On Low Sidelobe

Compared with pulse radar,continuous wave radar can gain better radar characteristics under the condition of the small average power and easier to get big time-bandwidth product,so that it can obtain high range resolution and velocity resolution.Since the 1980's,the technology of continuous wave radar had been studied deeply in theory and developed greatly in the field of civilian applications.This paper selects several typical radar signal,including chirp signal,m-sequences and Barker code in two-phase encoded signal,Frank code and P4 code in multi-phase encoded signal,Costas-coded signal,pseudo-random sequence(m-sequence)frequency encoded signal and noise-frequency encoded signal in frequency encoded signal,Frank-Costas complex coded signal and m-Costas complex coded signal in frequency-phase complex encoded signal.In this paper,we analysis some important characteristics of the signals we mentioned above.These characteristics are time and frenquency domain waveform,aperiodic and periodic ambiguity function and aperiodic and periodic autocorrelation function.And then we focus on the MCPC signal.Firstly we analyze the basic structure of MCPC signal.Based on characteristics of the good orthogonality between its various sub-carrier frequency signal,we study a two-stage pulse pressure method to process the echo signals of MCPC and carry on the simulation verification of the method.Secondly,we analyze and simulate the time-domain characteristics and autocorrelation properties of the MCPC single pulse signal,IIS MCPC burst signal and COCS MCPC burst signal.As for low-sidelobe,we study on the least square(LS)and linear programming(LP)mismatch filter method to suppress sidelobe of signals.Firstly,we analyze the algorithm method of two kinds of side lobe suppression theories.Secondly,we carry on the simulation analysis of the signals.For LS method,we analyze the effect of sidelobe suppression of both periodic and aperiodic signals.We do the further research to the side-lobe performance of the aperiodic signals on the effect of different filter order and whether weighted.And then we research the effect of different filter order to the peak sidelobe ratio,integral sidelobe ratio and SNR loss of the phase encode signals.And also we do the further research to the side-lobe performance of the aperiodic signals on the effect of different filter order and whether weighted.