WCDMA中联合迭代信道估计与解码的研究

首先介绍了基于WCDMA系统中RAKE接收机的信道估计方法，然后将Turbo原理引入信道估计，针对WCDMA系统提出两种迭代信道的估计方法。通过使用RAKE接收机或解码之后的软信息来改善整个WCDMA系统的性能，对WCDMA系统中联合运用信道估计与解码技术进行了研究。由于联合信道估计与解码技术可以利用通信系统不同模块之间的“软信息”交换，从而有效地提高了信道估计准确程度和解码器的性能。仿真结果表明，利用解码之后的软信息来修正信道估计的方法较传统的RAKE接收机中的信道估计方法性能有较大改善，在误码率为10^-2左右时，提高大约1dB。

Joint Iterative Channel Estimation and Decoder in WCDMA System

Firstly, the channel estimation in RAKE receiver based on WCDMA system is reviewed. Secondly, the Turbo encoding is integrated in the channel estimation algorithm. Two iterative channel estimation schemes with soft decision feedback for WCDMA system is considered. Joint channel estimation with soft output from RAKE receiver and associated decoder techniques are also discussed. Using these techniques, the precision of channel estimation and the performance of decoder can be improved effectively by exchanging information between different units of a communication system. Results of simulation demonstrate that the method of using soft information obtained from encoding to improve the precision of channel estimation is much better than the method used in traditional receivers. Under the condition of 10-2 BER for decoder feedback, performance can be improved about 1 dB.