A Study on a Multi-carrier Multi-code based Next Generation DVB-T System

• Main Authors: Ying-Hung Li, 李盈宏
• Other Authors: Chia-Chi Huang
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/28822716992594594420

碩士 === 國立交通大學 === 電信工程系所 === 94 === DVB-T system is based on OFDM system, but the performance of OFDM system is limited by the interference of multi-path channel. To solve this problem, in this thesis we combine the OFDM and CDMA transmission techniques with walsh codes which has perfect orthogonality for data spreading. And we also use the iterative soft multi-path interference cancellation to improve the performance of the system. In addition, we use LDPC code, which can be close in the Shannon limit, to replace two codes which are used by DVB-T system. And we also propose a turbo equalization to improve the performance of the multi-path interference cancellation and the channel decoder by using the iterative pass of soft information between equalizer and decoder. Finally, the performances of these techniques mentioned above were evaluated by computer simulation in multi-path fading channels and from the simulation results, the performances are improved effectively.