基于消除误差累积的OFDM信道估计算法研究

Channel Estimation Based on Elimination of Error Accumulation in Time Variant Multi-path OFDM System

在LS算法和判决指导算法基础上，提出了基于消除误差累积的时变多径OFDM系统信道估计算法。消除误差累积算法使用低频率插入导频的方法来消除判决指导算法中误差累积传播问题，在兼顾系统有效性的同时增强了系统的可靠性。仿真结果表明，当插入导频的频率可以跟踪信道的突变速率时，该方法可以很好的抑制判决指导算法中的误差累积传播问题，其误码性能可以改善1—2个数量级。

A new channel estimation algorithm based on LS algorithm and adjudging guidance algorithm is presented which is applied in the time variant multi-path OFDM system. The new algorithm solves error accumulation propagation in adjudging guidance algorithm. Considering the efficiency of the system, the new algorithm improves reliability greatly compared to adjudging guidance algorithm. The simulation results show that when the frequency of inserting pilots can follows the channel variation rate, error accumulation propagation can be restrained well with the proposed algorithm, and the performance of BER can increase by ten to twenty times.