一种基于Kalman滤波器的低复杂度信道估计算法

在HF通信中，信道具有时变性，准确地跟踪信道对于接收端是必不可少的，提出了一种半盲迭代信道估计和译码的联合接收方案。通过较短的训练序列对信道进行初估计，假设当前时刻的信道参数不变，当信息数据来临时，进行一次译码，译码后的数据比特作为信道的先验输入信息，对信道实时跟踪，再进行下一次译码，直到满足条件为止。将信道估计引入迭代过程中，在增加少量复杂度的情况下，可提供较为精确的信道信息。

A channel estimation algorithm with low complexity based on extended Kalman filter

It is indispensable to track accurately the HF channel because of its time variation for the receiver. A joint scheme about semi blind channel estimation and decoding is proposed. A shorter periodic (non-random) training sequence was used to estimate the channel which was supposed to be invariable at present, the subsequent information sequence was decoded and sent to channel as the apriori sequence. Then the channel estimation and decoding were performed in turn again up to content result. The iterative approach provides reliable channel information with low computational complexity.