一种新的多址信道有效阶数估计算法

A Novel Algorithm for Multi-access Channel Effective Order Estimation

针对多用户正交频分复用/空分多址(OFDM/SDMA)系统上行链路多址信道,基于噪声信道提出了一种新的信道有效阶数和信道冲激响应联合估计算法。该算法以最大似然为目标函数,构建了基于差分进化并行搜索信道有效阶数并进行信道冲激响应估计的联合框架。算法引入赤池信息量准则作为搜索阶数最优的评判函数,以提高信道有效阶数和信道冲激响应的估计精度。仿真验证了所提算法的有效性和可靠性,结果表明引入赤池信息量准则(AIC)在降低有效信道阶数估计误差的同时提高了时域最大似然信道估计器的性能。特别地,在误码率为10-5时,所提算法能够获得约1.5 dB的性能增益。

In order to improve the precision of channel parameter estimation, a novel channel effective order estimation scheme is proposed for multi-user Orthogonal Frequency Division Multiplexing/Space Division Multiple Access（OFDM/SDMA） uplink system in this paper. Exploiting Akaike＇s Information Criterion （AIC） as the evaluation function to search the optimal order, this scheme performs a joint channel ef- fective order and channel impulse response estimation in a parallel way based on the differential algorithm. With the introduction of AIC, it can reduce the estimation errors of multi-access channel effective order. Simulation results verify the validity and reliability of the proposed scheme. It is also shown that the proposed scheme achieves a better mean square error performance than the fixed channel order scheme and improves the performance of time-domain Maximum Likelihood channel estimator.