中文摘要：

提出了衰落信道下的一种迭代盲信道估计与译码算法，推导了高阶调制下的MAP估计和ML估计表达式，并证明了在信噪比充分大或块衰落信道的块长充分大时。MAP与ML估计是等价的。通过仿真发现，在对迭代信道估计与译码算法的影响上，信噪比与衰落信道的块长之间存在着折中关系，并分析了块衰落信道的块长对迭代信道估计与译码算法的性能的影响。

英文摘要：

An iterative blind channel estimation and decoding algorithm for block fading channels is proposed. MAP and ML estimation expression is derived and it proves that MAP estimation is equivalent to ML estimation when SNR or the block length of the block fading channel goes to infinity. Simulation results show that there is a tradeoff between SNR and the block length of block fading channels which determine the performance of the proposed iterative algorithm. The impact of the block length of block fading channels on performance of the proposed algorithms is analyzed.