| 摘要: |
| 针对DS/FH（直扩/跳频）混合扩频信号截获和参数估计问题，提出了一种基于延时相
乘结合自适应滤波和分段自相关的新方法。该算法首先将输入信号进行自适应滤波以提高
信噪比，滤波后送入延时相乘器，最后将乘积后数据分段进行自相关，通过分析谱图即可检
测DS/FH混合扩频信号的码速率谱线。计算机仿真显示，改进的算法不但能适应低信噪比(
-2
0 dB)条件下DS/FH混合扩频信号的检测，而且同时能够实现对码速率的估计。该方法所用
算法简单，适合采用硬件设计实现，且如果是合作目标信号，搜索时间短，实时性强。 |
| 关键词: DS/FH混合扩频 信号检测 延时相乘 分段自相关 自适应LMS
滤波器 |
| DOI： |
|
| 基金项目: |
|
| Detection and chip rate estimation of DS/FH hybrid signals based on delay-multiply and its improved algorithm |
| ZHANG Lei,MENG Fan-ji,HU Jian-ping,WANG Yu-wen |
| () |
| Abstract: |
| To deal with the issue of DS/FH(direct sequence spread spectr
um /frequency hopping) hybrid signal interception and parameter estimation,
a novel algorithm based on delay-multiply,sectional auto-correlation and adapti
ve filter is proposed．In this algorithm,the input signal is processed by adapti
ve f
ilter to improve signal-to-noise ratio(SNR) first. Secondly, the filtered signal
is sent to
delay-multiply and sectional auto-correlation is performed. Finally, the chip ra
te can be detect
ed by analysing the power spectrum. The computer simulations show that it can no
t only fit the need of the low SNR(about -20 dB) which is
quite
common in the detection of DS/FH signals，but also can give the estimations of
the chip rate in a simple way．This algorithm has little calculating demand so i
t is suitable for hardware implementation. If the input signal is cooperative s
ignal,the search time will be shorter,and the algorithm has good capability in
real-time processing. |
| Key words: DS/FH hybrid spread spectrum signal detection delay-multiply sectional auto-
correlation LMS adaptive filter |
