自适应滤波自编码扩频系统的同步捕获研究

在自编码扩频通信系统中,扩频码从随机数据流中产生,具有动态可变特性。利用自适应滤波提取扩频码的自编码扩频通信系统就是在传统自编码扩频通信系统的基础上,引入了谱估计中AR滤波的概念,动态地把信源序列转换成高斯白噪声分布的数据流,然后经二值量化得到具有良好相关特性与平衡性的伪噪声序列作为扩频序列。编码序列的同步捕获是自编码扩频通信系统中的关键技术。为了可靠地解调信号,必须建立快速、可靠的同步。本文即是针对这种自编码扩频方法提出的一种周期性地发送同步头的编码同步捕获方案,并对方案的性能进行了理论分析和实验仿真。

Study of Synchronization Acquisition Scheme for SESS System with AR Filter Algorithm

In self-encoded spread spectrum (SESS) communication system,the spreading codes are generated based on the random data stream and are time-varying random codes.Based on the traditional SESS system,a new method is presented to produce the SESS codes with the algorithm of auto-regressive (AR) filter in the estimation of power spectral density (PSD),by which the source sequence is converted into white Gaussian noise, and becomes pseudo-noise (PN) sequence with good relativity and balance after binary quantization.Acquisition algorithm for synchronization is a key technology in SESS system.For reliable signal de-spreading, rapid and reliable synchronization is needed.An efficient acquisition scheme based on transmitting the synchronization head periodically for SESS system with the algorithm of AR filter is presented in this paper,and the theoretical analysis and simulation are discussed in detail.