摘要
针对现有MIMO-OFDM分布式天线系统的定时同步算法不能准确估计精确符号定时的局限性,提出了一种MIMO-OFDM分布式天线系统的定时同步算法,新算法设计了一个正交变周期训练序列(OVP)集,每根发射天线的前导符号由此集合中的一种训练序列构成,利用天线间训练序列的正交性和变周期性,在接收端定义了相应的帧头捕获度量函数和精确符号定时度量函数,能准确地估计出分布式天线系统的时延矩阵。仿真结果显示:无论在AWGN信道还是多径衰落信道下,各天线时延和天线间时延(ITD)的估计性能都要优于传统算法,有效地解决了MIMO-OFDM分布式天线系统的精确符号定时同步问题。
For the inaccuracy of symbol timing estimation in the existing timing synchronization algorithms, a novel algorithm is proposed for multiple input multiple output-orthogonal frequency division multiplexing （MIMO-OFDM） systems with distributed antennas. A set of orthogonal variable-period （OVP） sequences is designed for this algorithm. The preamble used for timing synchronization of a transmitting antenna consists of several identical training sequences which are taken from the sequence set. At the receiver, the orthogonality and period variability among training sequences are used to design the metric functions for frame capturing and symbol timing. This method can accurately estimate the time offset matrix and greatly improve the performance of timing synchronization in multi-path channel. Simulation results show that no matter in AWGN channel or in multi-path channel, the proposed algorithm outperforms traditional methods in estimating time offset of each antenna element and the inter transmitter delay （ITD）. It effectively solves the problem of symbol timing synchronization in MIMO-OFDM systems with distributed antennas.
出处
《电波科学学报》
EI
CSCD
北大核心
2010年第4期717-724,共8页
Chinese Journal of Radio Science
基金
国家自然科学基金(60672065)
湖南省教育厅基金项目(09C960)
