Baseband Signal Processing Algorithms And Implementation Of SSR Based On FPGA

With increasingly complicated practical needs in reality,and traditional algorithm of the Baseband signal processing,this thesis describes the basic principle and the main component of SSR firstly, emphasizing on the framework and function of the Baseband signal processing. In the aspect of signal format and communication protocol, the article makes a detailed introduction of the two data link models of SSR: mode A / C and mode S.and then we present a series of new algorithms of the Baseband signal processing: In the A / C mode signal processing, this algorithm focuses on multi-targets garbling, dephantom and defruit based on Sum to difference relation , Rising edge and Falling edge,MTL and Bit confidence;In the S mode signal processing, the algorithm includes declaring of data bit and confidence of bit and error correction,as well asDMTL for High dynamic range receiver ,which raises the sensitivity of S mode signal processing.Based on the simulation algorithm, this paper sets up the hardware verification platform based on FPGA and completes the realization of hardware circuit design and software algorithm with VHDL codes, system simulation. Verification shows that the above algorithms all achieve satisfying effects. Furthermore, algorithm of mode A/C can process three overlapped targets and S mode can exactly process the signals with power as low as-78dB. They improve the system accuracy and reliability of the A/C and S modes , then are quite useful in engineering.