Research On The Low Complexity Synchronization In TD-SCDMA Downlink

TD-SCDMA has been successfully applied to commercial aim and the new mobile communication technologies such as TD-LTE have been developed and tested. Generally, the synchronization unit repuires many hardware resources in these communication systems. Therefore, it attracts much attention on how to reduce the complexity of synchronization modules.First, based on the TD-SCDMA special frame structure and the previous researches, this manuscript studied several pre-synchronization algorithms of power ration detection (PRD), and then investigated the quantized word length influence and the output word truncation. Simulations reveal the optimal value of quantized threshold and the output truncation length, which significantly degrades computation loads of the pre-synchronization algorithm. Moreover, this thesis proposed two fine synchronization algorithms with low complexity and good performance, whose quantization effects were also analyzed. The above algorithm were tested by MATLAB simulations, the result demonstrated that the proposed method was of less computations while maintained good performance in a larger signal-to-noise ratio (SNR) range. In order to further validate the proposed algorithm, the FPGA simulation including both the PRD pre-synchronization and the fine synchronization were prformed, resulting in reliable and consistent results.Taking into consideration that TD-SCDMA and the TD-LTE have similar frame structures, we extend the proposed pre-synchronization algorithm to the TD-LTE system. The MATLAB simulation showes a good performance of pre-synchronistion.