Journal of Systems Engineering and Electronics ›› 2012, Vol. 34 ›› Issue (6): 1102-1107.doi: 10.3969/j.issn.1001-506X.2012.06.04

• 电子技术 • 上一篇    下一篇

非周期直扩信号PN码盲估计技术

张晓林,李洪源   

  1. 哈尔滨工程大学信息与通信工程学院, 黑龙江 哈尔滨 150001
  • 出版日期:2012-06-18 发布日期:2010-01-03

Approach to blind estimation of PN sequence in nonperiodic DSSS signals

ZHANG Xiao-lin,LI Hong-yuan   

  1. College of Information and Communication Engineering, Harbin Engineering University, Harbin 150001, China
  • Online:2012-06-18 Published:2010-01-03

摘要:

在非协作信息侦测情况下,在扩频周期内,由于非周期性直接序列扩频(direct sequence spread spectrum, DSSS)信号的扩频序列具有不可重复性,再加上扩频信号的非同步性,使得扩频码的盲估计十分困难。在信息序列不相关,且已知扩频码周期、码速率和信息速率等参数的前提下,提出一种针对非周期性DSSS信号PN(pseudo-noise)序列的盲估计方法。该方法按照信息码元宽度进行分段,利用子空间跟踪算法估计各段PN序列,结合滑动窗口方法实现盲同步,并按照一定的顺序排列拼接实现PN序列盲估计。仿真结果表明,该方法运算量小,对存储空间要求低,在低信噪比条件下可快速准确恢复PN码序列。

Abstract:

It is difficult to estimate pseudo-noise (PN) sequence in nonperiodic direct sequence spread spectrum (DSSS) signals because of the nonsynchronization and irrepeatability in different durations of PN sequence  of nonperiodic DSSS signals in a noncooperative context. An efficient method that can estimate the PN sequence of DSSS signals is presented under the conditions that duration and rate of PN sequence, rate of information sequence is known and information sequence is irrelevant. With the help of sliding window, the blind estimating is achieved based on projection approximation subspace tracking (PAST) algorithms, and the PN sequence can be estimated after sorting and splicing. The experimental results show that this algorithm can estimate PN sequence quickly and accurately at low signal-to-noise ratio (SNR), largely reducing computational complexity and storage.