一种基于物理熵源的扩频随机序列的产生及其扩频特性分析

摘要

The performance of spread spectrum communication systems is directly affected by the statistical performance of spread spectrum sequences. How to find novel high-speed spread spectrum sequences with good performance has been the focus of modern communications research. In this paper,the chaotic signal output from the semiconductor la-ser is used as the source of physical entropy. The double-precision auxiliary operation is performed by the photoelectric conversion and the Simulink platform,and a 4Gb/s high-speed physical random sequence is obtained.The true random feature was tested by the NIST standard test software and satisfies 15 test criteria,indicating that the random random nature of the obtained random physical sequence is excellent. Through the simulation of the spreading characteristics of truncated physical random sequences and chaotic sequences,the results show that the randomness,orthogonality,corre-lation and equalization of random sequences based on physical entropy source are significantly better than those of chaot-ic spread spectrum sequence.%扩频序列的统计性能直接影响扩频通信系统的性能,如何寻找性能优良的新型高速扩频序列一直是现代通信的研究重点.以半导体激光器输出的混沌信号作为物理熵源,经光电转换与Simulink平台进行双精度辅助运算,获得了4Gb/s高速物理随机序列.经NIST标准测试软件对其真随机特性测试,满足15项测试指标,表明得到的物理随机序列真随机特性优良.通过对截短物理随机序列与混沌序列的扩频特性进行仿真,结果显示基于物理熵源的随机序列经优选的随机性、正交性、相关性和均衡性几个方面显著优于混沌扩频序列.