CAJ | 학술논문

针对长期演进(LTE)下行正交频分复用(OFDM)系统的最小二乘(LS)信道估计算法对噪声比较敏感的问题,提出了一种基于小波变换去噪与变换域插值相结合的信道估计方法.该方法通过在最小二乘(LS)估计之后加入小波阈值去噪过程,再通过变换域低通滤波插值估计进行双重去噪处理.计算机仿真结果表明,该估计方法能够有效地去除加性高斯白噪声,比一般的LS估计算法性能要好,在一定程度上弥补了LS估计算法对噪声敏感的缺陷.
침대장기연진(LTE)하행정교빈분복용(OFDM)계통적최소이승(LS)신도고계산법대조성비교민감적문제,제출료일충기우소파변환거조여변환역삽치상결합적신도고계방법.해방법통과재최소이승(LS)고계지후가입소파역치거조과정,재통과변환역저통려파삽치고계진행쌍중거조처리.계산궤방진결과표명,해고계방법능구유효지거제가성고사백조성,비일반적LS고계산법성능요호,재일정정도상미보료LS고계산법대조성민감적결함.
To solve the problem that least-squares (LS) channel estimation is sensitive to the noise, a new method of channel estimation in the LTE (long term evolution) orthogonal frequency division multiplexing down-link transmission system is proposed. The method combines wavelet de-nosing with interpolation in the transform domain, and it reduces the effect of the noise acting on the channel estimation effectively. This channel estimation method uses least-squares (LS) estimation at first, then uses the wavelet de-noising by thresholding and interpolation based on low-pass filter in the transform domain to reduce the noise. As verified by computer simulations, the proposed method exhibits high estimation accuracy, because it can eliminate the additive white Gaussian noise effectively, so it makes up the flaw of LS estimation which is sensitive to the noise.