MIMO系统中迭代捕获算法的性能分析

基于迭代消息传递的伪码捕获方法能够在复杂度较低的情况下,极大的提高捕获速度,但在低信噪比下捕获性能下降很快。多输入多输出(MIMO)系统可以在不增加频谱资源和发射功率的条件下,削弱多径衰落,改善通信系统的性能。本文提出将迭代捕获算法应用于MIMO系统中,在接收端采用分集技术,运用最大比合并方法进行信号合并,然后用迭代算法进行捕获。仿真结果表明:将迭代捕获算法与MIMO系统结合,在不影响捕获速度的前提下能够有效提高信号的捕获概率,信噪比在-22dB条件下捕获概率达到90%以上,性能优于现有的迭代捕获算法。

Analysis of Iterative Acquisition Algorithm in MIMO Systems

The pseudocode acquisition method based on iterative message passing algorithm(IMPA) is able to improve the acquisition speed greatly under the low complexity condition,but decrease fast in the poor SNR conditions.In the multiple input multiple output(MIMO) systems,it can weaken the multi-path fading,and improve the performance of the communication systems without increasing the spectrum resource and the transmit power.In this paper,the IMPA used in MIMO system is proposed,in which the diversity technique is adopted in the receiver side,the maximal ratio combining(MRC) method is used to combine the received signals,and then the IMPA is used to acquire the signals.Simulation indicate that the IMPA used in MIMO can improve the acquisition probability effectively without impacting acquisition speed,the acquisition probability can achieve 90% when SNR is-22dB,and the performance is better than the existing method.