MIMO-OFDM系统中一种有效的信道估计方法

在多输入多输出正交频分复用(MIMO-OFDM)系统中，采用梳型训练符号的传统信道估计技术在子载波边缘会产生相当大的均方误差(MSEs)。为了减少这些子载波上的MSEs，提出了一种循环的梳型训练结构。在这种结构中，所有类型的训练符号都在每个天线上循环地发送。在接受端，用每个训练符号来估计信道频域响应，并采用与MSEs相对应的权重因子来平均这些响应。计算机仿真结果表明，这种循环的训练结构能够提供比传统的结构更高的信噪比(SNR)。

Enhanced Channel-Estimation Technique for MIMO-OFDM Systems

In multi-input multi-output orthogonal frequency-division multiplexing systems,conventional channel estimation techniques using comb-type training symbols give relatively large mean squared errors(MSEs) at the edge subcarriers.To reduce the MSEs at these subcarriers,a cyclic comb-type training structure was proposed.In the proposed cyclic training structure,all types of training symbols were transmitted cyclically at each antenna.At the receiver,the channel frequency responses that were estimated using each training symbol were averaged with weights obtained from the corresponding MSEs.Computer simulations show that the proposed cyclic training structure gives more signal-to-noise ratio gain than the conventional training structure.