摘要
提出了基于小波块阈值降噪的OFDM信道估计算法。该算法通过对最小二乘信道估计算法的结果进行小波块阈值降噪来提高信道估计性能。与传统信道估计算法相比,块阈值降噪算法由于利用了信道频率响应小波系数的局部相关性,在仅增加少量运算量的前提下,大大降低了信道估计的均方误差、系统的误符号率和计算复杂度,运算量仅正比于有效子载波数,且在系统CP长度小于信道多径时延扩展时算法仍然可以保持很好的性能。数值仿真结果证明了上述结论的正确性。
A block-thresholding wavelet denoising based channel estimation algorithm was proposed.The algorithm improved the channel estimation performance by denoising the channel frequency function estimated by Least Square Estimator using block thresholding wavelet denoising.Compared with the conventional algorithms,block thresholding wavelet denoising algorithm ultilized the local correlation of the wavelet coefficients,so using the proposed method the mean square error and symbol error rate can be reduced greatly,and the computation complexity is only linearly proportional to the number effective subcarriers.The proposed method also poses good robustness when the CP length of the system is shorter than the delay spread of the channel.Numeric simulations show the performance improvement of the proposed algorithm to the conventional ones.
出处
《计算机科学》
CSCD
北大核心
2011年第6期74-76,105,共4页
Computer Science
基金
国家自然科学基金项目(60802009)
"十一五"国家863计划课题项目(2008AA01Z204)等资助
关键词
OFDM
信道估计
小波降噪
块阈值
OFDM
Channel estimation
Wavelet denoising
Block thresholding
