Adaptive Spreading Code Assignment for an Expanded Time-Frequency OFDM System with a Zero-forcing Equalizer  

作　　者：WU Bo SHANG Yong XIANG Haige 

机构地区：[1]School of Electronic Engineering and Computer Science, Peking University, Beijing 100871, China

出　　处：《Chinese Journal of Electronics》2011年第2期312-316,共5页电子学报（英文版）

摘　　要：The Expanded time-frequency （ETF-） OFDM system uses the two-level spreading technology for data transmissions. This system has shown to be robust against the narrowband jamming in flat fading channels. However, in multipath fading channels, the orthogonality of its spreading codes can be destroyed. To mitigate the adverse effects of multipath fading, narrowband jamming, and white noise in ETF-OFDM systems, we propose a transmission approach that finds a proper spreading code assignment at the transmitter and adopts the zero-forcing equalizer at the receiver. Simulation results show that the proposed scheme enables the ETF-OFDM system to suppress the interference under multipath fading channels.

关 键 词：Code division multiple access （CDMA） Orthogonal frequency division multiple access （OFDMA） Resource allocation. 

分 类 号：TN929.5[电子电信—通信与信息系统] U491.123[电子电信—信息与通信工程]