OFDM系统中的信道自适应估计与跟踪算法比较

摘要

传统的QR分解和投影逼近子空间(PAST)分解算法,可用于矩阵的奇异值分解和秩数的估计.讨论了在正交频分复用(OFDM)通信系统中基于这两种分解方法对导引信号的子空间进行分解,实现信道矩阵的自适应跟踪估计.采用这种算法,降低了矩阵运算的雏数,使每个符号期间信道估计的运算量减少,信道估计的均方误差减小,接收机的误码性能得到改善,同时利用计算机模拟,对两种算法运用到信道估计中的跟踪性能进行了比较.%The traditional QR factorization and projection approximation subspace tracking (PAST) algorithm are used to singular value decomposition and to estimate the rank.The pilot based channel estimation and tracking for orthogonal frequency division multiplexing (OFDM) system is discussed.The two algorithms are used to track the channel metrix subspace, the channel adaptive tracking and estimation are realized, the rank and the calculation amount are reduced.The performanees of the mean square error (MSE) is improved.The performance of the two subspace tracking algorithms are compared through the computer simulation.