Research And Application Of Td-scdma System Turbo Decoder

With the rapid development of technology, people need advancing communication quality to transporting video and voice data. As a result, communication standards are improved. As the next generation of mobile communication standard of China, TD-SCMDA is accepted and identified by the world. Beyond some obvious characters like time synchronization and Code Division Multiplexing, TD-SCDMA also adopts turbo coding technology.Turbo code is paid much attention for its near Shannon limits capability. It is the suggested channel code solution in the high transporting rate environments according to TD-SCDMA standard. For the special decoding methods and MAP decoding algorithm, turbo decoding is hard to meet the requirements of real-time data transport.In this paper, we study the algorithm of turbo decoding aiming at the implementation of low-complexity and short-delay decoder. Matlab simulation method is used in the paper. Using the results of the simulation, we optimize some parameters as sliding-window length and iteration time. Some important modules are also realized by the C language to get the parameters of hardware implementation.Finally, this paper discusses the RTL (Register-Transfer-Level) implementation methods. From the simulation results with EDA tools, bit error rate and time delay are estimated. The feasibility of RTL design is also confirmed by comparison with the other analogous and finished Turbo decoders. Some improving advices are also put forward in the end.