Research On Channel Estimation And Equalization In Cmmb

With the development of information technology, mobile multimedia broadcasting is going to be an important application of broadcasting and TV industry. In the recent years, China Mobile Multimedia Broadcasting (CMMB) is published by the State Administration of Radio Movie and TV, and has becomed a hot research. CMMB is an OFDM system based on the cyclic prefix (CP). Channel estimation and equalization is one of key techniques in the wireless communication area and one of the most important modules as well. In the thesis, the algorithm and implementation of channel estimation and equalization of CMMB system have been studied.The thesis proposes a method to solve the problem caused by the discontinuous of CMMB scattered pilots when applying the LMMSE based algorithm. Meanwhile, the improved DFT algorithm has been simplified in order to reduce the complexity.Cascaded one-dimensional interpolation method is adopted to complete two-dimensional channel estimation in CMMB to reduce the complexity of compution. At the same time, a new solution is proposed to solve the problem caused by the discontinuous of CMMB scattered pilots and the edge sub-carrier in the channel estimation process. Simulation result shows that the performance has improved about 3db compared with the traditional algorithm.At last, the channel estimation and equalization algorithm is chosen to implement considering the system performance and complexity. The verilog HDL model is proposed. And the module is implemented by FPGA(EPⅡC s180).