Design And Implemetation Of Concatenated System Based On CPM And LDPC

The Continuous Phase Modulation (CPM) can be decomposed into a Continuous Phase Encoder (CPE) and a Memoryless Modulator (MM). The CPE is equivalent to a convolutional encode. It also has some coding gain. Hence, it can be form a traditional concatenated code system with CPM as inner code and LDPC as outer code. Obviously, the performance of power-efficient can be greatly improved by this kind of system. The key point is the complexity of system should be achievable.LDPC is a kind of Error-Correcting code which becomes focus in recent years. It uses message propagating between check-nodes and variable-nodes to carry out iterative decode. It both has advantage of performance and complexity.In this thesis, we introduced the encode algorithms and decode algorithms of LDPC and the design principle of H matrix. A decomposition approach to CPM is developed. We introduced the common Viterbi decode algorithms of CPM. We gave the diagram of concatenated system of MSK and LDPC, which is based on SISO BCJR algorithms. Based on the simulation result of different parameter, we analyzed the relationship between interleaver and system performance. We also gave the common principle of interleaver design. At last, we introduced one of the FPGA design of LDPC encoder and decoder.