MIMO-OFDM系统定时与多径时延估计

提出的多入多出正交频分复用（MIMOOFDM）系统的定时估计和多径时延算法主要基于本地训练序列与接收信号的相关运算，其中引入噪声估计、一阶无限冲激响应（IIR）滤波器及删除相关值旁瓣处理，以提高定时估计精度；引入多帧联合统计，以提高多径时延估计精度. 仿真结果表明，该算法可有效抵抗频率选择性衰落信道影响，在低信噪比条件下，达到精确的定时同步；在信噪比大于6 dB，信道抽样速率为20 MHz时，多径时延估计均方误差（MSE）可达到10-7.

Timing and Multipath Delay Estimation for a MIMO-OFDM System

Timing estimation and multipath delay estimation algorithms for a multi input multi outputorthogonal frequency division multiplexing (MIMOOFDM) system were presented. The basic principle of these algorithms is based on the correlation operation between a local training sequence and the sampled received signal. Noise estimation, 1order infinity impulse response (IIR), and deleting the correlation lobes peak value were introduced to improve the performance of timing estimation. Probability statistics for multipath delay of multiframe was introduced to improve the performance of multipath estimation. Simulation results indicate that the algorithms are robust against a frequency selective fading channel: The timing synchronization algorithm shows satisfactory performance even at a low signaltonoise ratios (SNR), and mean square error (MSE) of 10-7 is obtained at SNR＞6?dB for the multipath delay estimation, while channel sampling rate is 20?MHz.