Channel Estimation Algorithm Based On CMMB And Its FPGA Implementation

CMMB was issued as a china mobile multimedia broadcasting technology industry standards by the State Administration of Radio Film and Television with independent intellectual property rights. In this thesis, the definition and development of mobile multimedia broadcasting services are indicated. Currently, three major international mobile multimedia broadcasting standards are analyzed and compared, and the main technical characteristics of physical layer and the importance of channel estimation in the mobile multimedia broadcasting systems are discussed.Because of the significant advantages in the field of broadband wireless communications, Orthogonal Frequency Division Multiplexing(OFDM)technology has been widely applied in mobile digital TV terrestrial broadcasting systems.The basic principles of OFDM technology are discussed in this thesis. Channel state information can be extracted based on channel estimation methods in OFDM system receiver. Channel estimation solution for CMMB in OFDM system is indicated in the thesis.The wireless transmission scheme is introduced in this thesis. Then the characteristics of wireless broadcast channel for CMMB standard were analyzed. Impactions of Large-Scale fading wireless channels and Small-Scale fading wireless channels for wireless receiving signal are pointed out, and the Jakes channel models is established.The main channel estimation methods of scatter pilots based on CMMB are indicated in the thesis.These methods make full use of the scatter pilots information in CMMB standard, and they have good performances.A scheme suitable for FPGA implementation for CMMB channel estimation is presented in the thesis.Channel estimation algorithm for each module is implemented in the use of FPGA, and the functional simulation diagram is given. The simulation results show the effectiveness of the CMMB channel estimation solution based on FPGA.Finally, the work of this thesis is summarized and some notions for the future research are given.The simulation results show the effectiveness of the improved DFT interpolation algorithm and the linear--improved DFT two-dimensional interpolation algorithm.