摘要
将改进的有约束全域最优化方法与 Lorenz系统混沌同步方法相结合 ,提出一种对混沌CDMA扩频信号进行相位跟踪的新方法 .该方法不但吸收了优化方法中内、外点法相结合的混合型惩罚函数的有效性 ,而且保留了 Lorenz混沌同步方法中驱动信号对响应信号相位的逐步修正 ,非常适合于环境恶劣的移动信道 .模拟结果表明 ,新方法可获得比传统的“迟早门”检测器和一般的Lorenz系统混沌同步方法更低的系统误差 ,并能缩短平均搜索次数 ,对提高
A new method was proposed to realize the phase tracking of asynchronous chaotic CDMA spreading signals, which is based on the combination of improved restricted universal optimization method and Lorenz systems synchronization. It holds both the effectiveness of mixed penalty function that combines interior and exterior penalty methods in optimization, and the gradual modification to response signal by drive signal of Lorenz chaotic synchronization system, so this method fits the mobile channel in wicked conditions specially. The simulation results show that it can not only achieve lower minimal mean square error (MMSE) than the traditional early-late gate detector and generic chaotic synchronization of Lorenz system, but also shorten the average times of phase searching. So this method will operate in improving the receptivity of CDMA mobile communication systems significantly.
出处
《上海交通大学学报》
EI
CAS
CSCD
北大核心
2001年第11期1611-1615,共5页
Journal of Shanghai Jiaotong University
基金
国家自然科学基金重点资助项目 ( 69735 10 1
