通过分析时分同步码分多址(TD-SCDMA)系统的载波频偏和信道特性,提出一种频偏与信道联合估计算法。该算法通过对训练序列部分相关,然后做差分将频偏和信道特性解耦。并通过逐次迭代最终精确估计出频偏和信道参数。仿真结果表明,算法频偏估计性能接近Cramér-Rao界。准确度较高;全链路仿真误码率性能优越,信道估计准确。算法复杂度不高。实用性强,同样适用于其它的TDD模式的CDMA系统。
An algorithm of channel and carrier frequency offset joint estimation is proposed in this paper with analyzing the characteristic of carrier frequency offset and wireless channel in Time Division-Synchronous Code Division Multiple Access (TD-SCDMA) system. Frequency offset and channel parameters can be uncoupled by means of partly correlating the training sequence and calculating difference, then they are estimated accurately through iteration. Simulation results show that the proposed algorithm performs quite well in both frequency offset and channel estimation. The frequency offset estimation performance is closed to Cramér-Rao bound, and the link performance is good. The proposed method has low complexity and strong practicability. It can be used in other Time Division Duplex (TDD) CDMA systems.