Research Of Sidelobe Suppression And Doppler Compensation Algorithms For Biphase Coded Signal

The sidelobe suppression and Doppler compensation algorithms for biphase coded signal are emphasized on in this paper.First of all, basic characteristics of biphase coded signal are analysed, including time domain and frequency spectrum characteristics, autocorrelation function and feature of echoes, and two classical biphase coded sinals - Barker code and m sequence code - are also introduced. After that, a sidelobe suppression algorithm - optimal PSL mismatched filtering algorithm– is discussed. Mismatched filtering results of this algorithm in different reference sequences and different sampling rates are analyzed in detail, and the corresponding simulations and analysis are also given. Then two Doppler compensation algorithms are studied in detail, including the Doppler compensation algorithm based on phase correction and the Doppler compensation algorithm based on alternant m sequence code, and the corresponding simulations are given. The results indicate that these two algorithms can compensate Doppler frequency effectively. Meanwhile, the disadvantages and limitations are analysed, and comparison of these two algorithms is given. Finally, based on the research and development of a radar signal processing system, the sidelobe suppression algorithm and the Doppler compensation algorithm based on alternative m sequence code are implemented on TS201. The comparision and analysis of the processing results of DSP and MATLAB are given, which illustrates the effectivity and efficiency of these two modified algorithms in projects.