在TD-SCDMA系统中，采用了很多先进的关键技术如联合检测、智能天线技术等，用于提高系统性能，而这些关键技术的性能在很大程度上依赖于信道估计的精确性。本文主要研究TD-SCDMA系统中的上行信道估计方法，以提高信道估计的准确度。 本文首先介绍了无线移动通信信道的衰落特性，然后介绍了TD-SCDMA系统的物理信道格式，同时结合TD-SCDMA系统的特点建立了系统的离散传输模型和阵列天线下时延和角度扩展的信道响应模型。简要介绍了TD-SCDMA系统中信道估计原理和方法。 本文提出了一种改进的基于子空间的多时隙平滑的信道估计方法，对该方法进行了详细推导和仿真分析。基于子空间的多时隙平滑的信道估计方法根据多径衰落信道的时延和角度变化缓慢的特性，利用较多时隙平滑得到空域时域信号子空间投影的方法抑制了噪声抽头的功率，提高了信道估计的准确度。 另外，本文对TD-SCDMA系统中的多小区信道估计方法进行了改进，提出了一种多小区迭代信道估计方法，给出了迭代方法的详细流程。并与原多小区信道估计方法进行了仿真比较，多小区迭代信道估计方法能够进一步提高本小区信道估计的准确度。

Many advanced key technologies like Joint Detection,Smart Antennas have been used to enbaIl∞the system perfornmce in TD-SCDMA systems．But,these key technologies pcrform撇rely Oil the accuracy of channel estimation．In this paper We mainly study the channel estimation algorithm to enhan∞the accuracy ofchannel estimation． In this paper we first introduce fading characteristic of the wireless mobile communication channel，then introduce the basic formations of the physical channel．And make a discrete-time model and the channel response model with time delay expoJld and the angle a删which under the array antenna．We intfoduo：in briefly the channel estimate pnnciple and the algorithm in TD-SCDMA system． In this paper We propose an improved channel estimate algorithm based on the subspace multi-time slot smooth,and then carry 011 the detailed derivation and the simulation analysis to this algorithm．It uses multi-time slot smooth airspace time domain sign丑l subspaf．七to suppress noise tap power,improve the channel韶痂n鲥on accuracy,under its mlll矗-palh fading channel delay and angle change characteristics ofslow． In addition,in this paper We improve the multi-cell channel estimation algorithm in TD-SCDMA system，propose a multi-cell iterative channel estimation algorithm,and describe the detailed iterative pID∞豁．Compare with the original multi-Cell channel estilnation by simulation．Multi—Cell iterative channel estimation algorithm may further enhance the channel estimation accuracy．