| 摘要: |
| 对于任何一种扩频PN码捕获系统来说,捕获性能在很大程度上取决于检测概率P_D和虚警概率P_(fao)在常用的平方律PN码捕获检测器中,P_D和P_(fa)的准确值可由相关器输出信号的概率密度函数(pdf)来估计.这篇文章提出用一种抽样数据方法来导出pdf.结果发现,对于码同步时,pdf是非中心X平方(Chi-square)分布,然而,对于码非同步时,pdf是中心X平方分布.利用这些分布,用广义的Q函数导出了P_D和P_(fa)的闭合表达式.这些结果对研究扩展频谱的工程师在系统设计中调整各种临界参数是非常有用的. |
| 关键词: 扩频系统,检测概率 |
| DOI： |
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| 基金项目: |
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| Closed-form statistical analysis for square law PN acquisition detector performance in spread spectrum systems |
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| Abstract: |
| For any spread spectrum PN code acquisition system,the acquisition performance is strongly dependent on the probabilities of detection and false alarm P_d P_(fa).In the commonly used square law PN acquisition detector,the accrurate values of P_d,P_(fa)should be evaluated from the probability density function(pdf) of the correlator output signal.In this paper,a sampled data approach is proposed to derive this pdf.It is found that the pdf is a noncentral chi-square distribution for a synchronized code,but a central chi-square distribution for the unsynchronized situation.Using these distribution the closed form solutions for P_d and P_(fa)are given in terms of the generalized Q-function.These results Will be very useful for spread spectrum engineers to adjust critical parameters in system design. |
| Key words: Spread Spectrum Systems,Probabilities of Detection |
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