OFDM电力线通信系统的时域信道估计方法

针对G3-PLC协议,提出了两种改进的时域信道估计方法。为达到时域降噪效果,采用了预置电力线信道最大时延的方法,但这使得相关的时频变换矩阵不满秩,无法直接采用最小二乘准则估计其时域特性。因此,文中提出一种基于修正变换矩阵的时域LS算法,解决了矩阵不可逆问题。同时进一步提出了一种无需信道统计特性的时域线性最小均方误差算法,大幅降低了复杂度。仿真结果表明,修正的时域LS算法和简化的时域LMMSE算法均性能良好。

Time-domain Channel Estimation Method for OFDM Power Line Communication System

For the G3-PLC protocol, two improved time-domain channel estimation methods are proposed in this paper. Presetting the maximum-delay of power line channel is used to achieve time-domain noise reduction. However, the corresponding time-frequency transform matrix is rank-deficient, and the LS criterion is not suitable for estimating the time-domain characteristics. To solve the problem, this paper presents a time domain channel estimation method based on modified matrix. And a time-domain LMMSE channel estimation method without channel statistics is proposed to reduce the complexity of the algorithm. The simulation results show that both the modified LS algorithm and the simplified LMMSE algorithm have good performance.