Adaptive Hybrid Acquisition of PN Sequences Based on Automatic Multipath Cancellation in Frequency-Selective Rayleigh Fading Channels
Adaptive Hybrid Acquisition of PN Sequences Based on Automatic Multipath Cancellation in Frequency-Selective Rayleigh Fading Channels
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DOI：
10.1007/s11277-010-0112-7
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发表时间：
2010-08
影响因子：
2.2
通讯作者：
L. Hacini;A. Farrouki;Z. Hammoudi
中科院分区：
文献类型：
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作者：
L. Hacini;A. Farrouki;Z. Hammoudi
提出并研究了一种在频率选择瑞利衰落信道下直接序列码分多址通信的混合pn码采集方案。该系统最重要的特征是它能够动态估计可能位于参考信道中的多径信号的数量。所考虑的算法的基本思想是对部分相关进行排序，并通过更新噪声估计进行连续的滤波测试，直到第一次路径同步。导出了虚警概率和平均采集时间的精确表达式。研究了该系统的性能，并与自适应混合采集处理器（AHAP）和有序统计混合采集处理器（OSHAP）的性能进行了比较。研究了不同信道参数对采集性能的影响，即可分辨路径数、多径强度分布和信噪比。数值计算结果表明，所提出的获取方案优于传统的基于AHAP和OSHAP算法的获取方案。
A hybrid PN-code acquisition scheme is proposed and studied for direct sequence code division multiple access communications in frequency-selective Rayleigh fading channels. The most important feature of the proposed system is its ability to dynamically estimate the number of multipath signals that may lie in the reference channel. The basic idea of the considered algorithm is to sort the partial correlations and carry out successive censoring tests by updating the noise estimation until the first path synchronization. Exact expressions for the probability of false alarm and the mean acquisition time are derived. The performances of the proposed system are then studied and compared with those of the adaptive hybrid acquisition processor (AHAP) and the ordered statistic hybrid acquisition processor (OSHAP). The effects of various channel parameters on the acquisition performance, namely the number of resolvable paths, the multipath intensity profile and the signal-to-noise ratio are also investigated. Numerical results show that the proposed acquisition scheme outperforms the conventional ones which are based on AHAP and OSHAP algorithms.