Multiuser Frequency Synchronization for Interleaved-OFDMA Uplink Systems  

作　　者：FAN Da CAO Zhigang 

机构地区：[1]Department of Electronic Engineering, Tsinghua University, Beijing 100084, China

出　　处：《Chinese Journal of Electronics》2008年第4期685-690,共6页电子学报（英文版）

摘　　要：This paper investigates the frequency synchronization in the uplink of the Orthogonal frequency- division multiple access （OFDMA） system with interleaved subcarrier assignment. In such a system, one of the key problems is the multiuser frequency synchronization, which focuses on the multiple-parameter estimation of the Carrier frequency offsets （CFOs）. In this paper, we propose a two-stage frequency offset estimation algorithm. The main advantage of the proposed method is that it can obtain the CFOs of all users simultaneously using only one OFDMA block. In addition, a novel CFO-compensation method is presented. Based on the inner signal structure of interleaved-OFDMA uplink, the new scheme uses adaptive beamformer to compensate the CFO of each user and isolate the signals of all users at the same time. Compared to the previously known methods, the proposed algorithm can provide accurate frequency synchronization and data detection without feeding CFO estimates back to active users for frequency adjustment.

关 键 词：Orthogonal frequency-division multiple access （OFDMA） Carrier frequency offset （CFO） Adaptive beamformer Matched filtering Minimum mean square error （MMSE）. 

分 类 号：TN914.51[电子电信—通信与信息系统]