一种新的TDCS基函数随机相位产生方法及性能分析

A new method of basis function's pseudorandom phase generation in TDCS and its performance analysis

针对一维M序列生成变换域通信系统伪随机相位的不足,提出了一种采用双混沌序列生成基函数伪随机相位的方法,利用混沌序列映射替代M序列映射,并增加由混沌序列决定的映射控制抽头将伪随机相位产生法由一维扩展到二维,分析了采用双混沌序列生成基函数的各项性能指标变化。通过仿真验证,结果表明,采用双混沌序列的基函数伪随机相位生成法,无论是在单用户或是多用户情况下,都能有效地降低系统的误比特率,提高系统的抗截获性能以及多址信道容量。

Based on the requirements of the pseudorandom phase vector in transform domain communication system （TDCS）, a new method using double chaos sequences in phase mapping during the basis function generat on in TDCS is proposed. The m sequences is substituted for chaos sequences, meanwhile, a mapping controlling tap whose series is de- pended on another chaos sequences is added in, which extends the one-dimensional method of generating pseudorandom phase into two-dimensional. The implementation method regarding the correlation and randomicity performance of the basis function are discussed in detail. The simulation resuhs show that both the Bit Error Rate （BER） performances of single us- er and multi-user using new method are improved, and thereby it enhanced multiple access channel capacity and Low Prob- ability of Intercept （LPI） of TDCS signals.