电力线中基于DFT的信道估计算法改进

Improvement of Channel Estimation Algorithm Based on DFT in Power Line

针对信号在线路传输中出现的反射、驻波等多径传输情况导致频率选择性衰落和噪声干扰等问题,提出一种基于离散傅里叶变换(Discrete Fourier Transform,DFT)的FA-DFT信道估计改进算法。该算法先通过子载波加权减小冗余信息对信道估计的影响,再根据DFT变换将时域变为频域,通过可靠性检验选择有效的信道估计。利用该信道估计值进行频域平均,可为不可靠的数据导频提供更好的信道估计。结果表明:该算法在误码率性能和均方误差的性能上更具优势,同时具有更好的健壮性。

Aiming at the problems of frequency selective fading and noise interference caused by multipath transmission such as reflection and standing wave in signal transmission,an improved FA-DFT channel estimation algorithm based on Discrete Fourier Transform(DFT)is proposed.Firstly,the algorithm reduces the influence of redundant information on channel estimation by subcarrier weighting.Then,the time domain is transformed into frequency domain according to DFT transform.The effective channel estimation is selected by reliability test,and the channel estimation value is used for frequency domain averaging to provide better channel estimation for unreliable data pilots.The results show that the algorithm has more advantages in bit error rate performance and mean square error performance,and has better robustness.