空时分组码MC-CDMA系统多用户检测

本文研究了在频率选择性瑞利衰落信道中工作于时分双工(TDD)模式的多载波码分多址(MC-CDMA)系统上行链路,在用户终端处使用两个发射天线,采用基于空时分组码的发射分集。考虑对应于子载波的衰落系数是信道冲激响应的离散傅里叶变换,给出了基于空时分组码的MC-CDMA系统上行链路信号模型。采用适用于同步CDMA系统的低代价Steiner估计器来进行基于空时分组码的MC-CDMA系统的信道估计,每个用户终端的两个发射天线各分配一个midamble。研究了基于空时分组码的MC-CDMA系统的解相关多用户检测、最小均方误差(MMSE)多用户检测,进行联合的多用户检测和空时码解码。仿真结果验证了上述模型及算法的有效性。

Multiuser Detection for a Space-Time Block Coded MC-CDMA System

In this paper, the uplink of a multicarrier code division multiple access (MC-CDMA) system in time division duplex (TDD) mode in frequency selective Rayleigh fading channel is investigated. Two transmit antenna are applied to the mobile terminal, using space-time block coding based transmit diversity. Based on the observation that the fading coefficients corresponding to subcarriers are discrete Fourier transform of multipath coefficients, the signal model of the uplink of a space-time block coded MC-CDMA system is presented. A low cost Steiner estimator for a synchronous CDMA system are proposed to perform channel estimation for a space-time block coded MC-CDMA system. A midamble is assigned to each of two transmit antennas in the mobile terminal. Furthermore, decorrelating multiuser detection and minimum mean square error (MMSE) multiuser detection are investigated for a space-time block coded MC-CDMA system. Joint multeruser detection and space-time decoding is conducted. Simulation results are listed to show the effectiveness of the above model and algorithms.