中文摘要：

利用所有发送天线同时发送的移位正交chu序列对已有的定时和频偏估计算法加以改进,提出了一种在多径衰落信道下具有高精度的快速多入多出-正交频分复用（MIMO-OFDM）系统定时和频偏估计新方法.分析表明,新方法具有定时准确检测概率高和小数频偏估计准确的优点,并且利用该算法可以在时域直接估计整数频偏,无需进行FFT运算,从而降低了系统同步的计算量.新算法的有效性在AWGN和第一径不是最强径的多径衰落信道下得到了验证.

英文摘要：

A fast and reliable technique with high performance for timing and frequency synchronization of multiple-input multiple-output （M IMO） orthogonal frequency division multiplexing （OFDM） system is proposed in multipath fading channel. The synchronization is achieved using shift-orthogonal chu sequence which is simultaneously transmitted from all transmit antennas in the same OFDM time instant. The analysis method gives out better detection properties in terms of higher correct timing detection probability and accurate fractional frequency synchronization. Furthermore, with the help of the proposed algorithm, the integral frequency offset in time domain can be obtained without FFT transform, that will reduce the computation complexity for the synchronization in MIMO-OFDM systems. The valid of the new algorithm is verified in AWGN channel and multipath fading channel in which the first path is not the strongest one.