基于MAP算法的OFDM系统迭代信道估计

提出一种运用在OFDM系统中的迭代最大后验概率信道估计方法。译码器利用信道估计值形成译码模块的软信息，通过交织，反馈到信道估计模块中，使外信息在信道估计模块和译码模块之间循环迭代。信道估计模块中采用线性最小均方误差算法对信道参数进行估计。通过信道估计模块和译码器之间软信息的循环迭代，充分利用有效的外信息，降低误码率，提高OFDM系统的性能。

Iterative Channel Estimation for OFDM System via MAP Algorithm

An iterative Maximum A Posteriori(MAP)channel estimation algorithm for Orthogonal Frequency Division Multiplexing(OFDM) system is proposed. The soft information from decoder is used by receiver. After interweaving the soft information, the receiver feeds them back to the channel estimator, in which the algorithm estimates the channel parameter. Through the iteration between the channel estimator and decoder, the useful soft information can be employed completely, which contributes to reduce the Bit Error Rate(BER), and improves the performance of the OFDM system.