一种有效的STBC-OFDM联合信道估计解码算法  

Efficient joint channel estimative and decoding algorithm for STBC-OFDM

作　　者：郑勇[1] 冯大政[1] 李晓明[1] 

机构地区：[1]西安电子科技大学雷达信号处理国家重点实验室,陕西西安710071

出　　处：《系统工程与电子技术》2009年第2期274-277,共4页Systems Engineering and Electronics

摘　　要：提出一种针对空时块码正交频分复用(STBC-OFDM)系统在信道不确知或时变情况下的低复杂度联合信道估计与解码算法。该算法推导的出发点是观察到STBC-OFDM系统中关于信道参数的最小二乘代价函数与只有线性处理的STBC解码最小二乘代价函数是等价的,从而可利用循环最小化迭代方法求解。在这两个代价函数求解各自参数过程中,可以充分利用OFDM的信号特征和STBC的正交结构特征,使计算量大为减少。在迭代过程中,信号先不考虑有限字符性质,而是取值任意的随机变量。估计出信号值后利用有限字符性质进行量化修正,避免了此类迭代算法中的穷举运算,从而降低了计算量,加速了算法收敛速度。仿真结果表明了该算法的有效性。A low complexity joint channel estimative and decoding algorithm for STBC-OFDM systems in time varying or unknown channel is presented. The starting point of derivation of the algorithm is the observa- tion that the least square cost function for channel estimate is equivalent to the one for standard STBC decoding, so the iterative method of cyclic minimization can be exploited for resolving them. The features of both the OFDM signal and the orthogonal structure of STBC can be exploited to reduce the complexity of resolving the two functions greatly. Duration the iteration, the signal is treated as a continuous variable other than a discrete variable, and then is adjusted using the finite alphabet property, which reduces the complexity and speeds up the convergence. Simulation validates the effectiveness of the algorithm.

关 键 词：信道估计 空时块码解码 正交频分复用 循环最小化 

分 类 号：TN973.3[电子电信—信号与信息处理]