使用混沌扩频序列增强DS/SS系统性能

基于Logistic映射，利用交织器设计扩频序列发生器，其产生的混沌序列具有良好的相关特性和旁瓣特性，并且是不必寻优而自身平衡的。将这种序列作为扩频序列应用于直接序列扩频系统中，能够有效地减少多址干扰，提高系统的容量，增强系统性能，信息也能够被加密。将这种序列和传统的扩频序列以及普通的混沌序列应用于扩频系统，仿真结果表明，设计的混沌序列性能优于其他的扩频序列。

Performance enhancement of DS/SS system using chaotic spreading sequence

In this paper,a chaotic sequence generator based on Logistic map and interleaver was proposed and used to generate spreading sequence.The generated chaotic sequence is balanced itself and has excellent correlation property and sidelobe property.When the sequence is applied to Direct Sequence/Spread Spectrum(DS/SS) system,Multiple Access Interference(MAI) can be mitigated by using the spreading sequences.The system capability and performance can be enhanced,and the information can be effectively encrypted.The Bit-Error Rate(BER) performance of spreading sequence from the proposed chaotic sequence generator was compared with that of the conventional m-sequence and Gold sequence.Results show that the new sequence has a noticeable improvement in BER performance in low Signal-toNoise Ratio(SNR).