Research On The Technology Of TPC In Two-channels Data Transmission System Based On Chase Algorithm

Turbo Product Code(TPC),is widely used in wireless communications, mobile communications, satellite communications, military communications and other fields due to its simple structure, low complexity of decoding,excellent performance of error correction, and the advantage of easy to realize. Based on the in-depth research and analysis of TPC encoding theory and decoding algorithm,this paper mainly studied the TPC decoding performance,and of it’s coding scheme and decoding algorithm In two-channels data transmission system combined with the need of practical application and the Chase algorithm.Firstly,this dissertation makes a study and analysis of TPC component code extended Hamming code algebraic decoding algorithm and its error correction ability, TPC coding principle and hard decision decoding algorithm on the basis of channel coding theory, laid a theoretical foundation for the later research.Secondly, this dissertation study the TPC Soft Input Soft Output iterative decoding algorithm based on Chase algorithm,and elaborated the decoding principle and the basic steps of the algorithm and the calculation process of soft information. Under the condition of AWGN channel, we make the BER simulatio n and analysis about the factors that influence the decoding performance. Simulation shows, After 3 iterations, relative to unencoded BPSK modulation system has coding gain of 5.7 d B, 3 btis quantization loss only 0.2d B than infinite bits quantization bits quantization when BER is 10-5. When the decoder can’t get channel information in the single channel data transmission system, this paper proposes a improved algorithm by increasing the sampling data to structure element reliability information.Finally, In the two-channels data transmission system, by adopting the idea of two-channels data jointly encoding, research the TPC algorithm. Combined with the application property of the two-channels data transmission system, under the circumstances of the decoder can and can’t receive reliability of information, put forward the dual differential encoding scheme and two-channels data merging decoding algorithm, then simulate in different channel conditions. The simulation results show that,decoding performance in two-channels data transmission system is superior then single channel data transmission system.