基于声光技术的扩频信号循环谱的检测

Detection of SS signal cyclic spectrum based on AO technique

扩频信号是被伪随机码调制的周期信号,因此它应被建模为循环平稳随机信号.基于循环平稳随机信号的谱相关理论,提出了一种采用基于声光信号处理技术的扩频信号循环谱检测方法.通过研究扩频信号的循环频率、循环功率谱和基于时间积分的声光循环平稳处理模型,利用声光循环平稳时间积分相关器,在循环频率处对扩频信号的声光相关函数(循环谱)进行检测.相比于传统的能量检测方法,循环谱检测方法具有更好的检测性能;对于噪声和干扰,无论是平稳的、还是非平稳的,循环谱检测方法都具有较强的抗干扰能力,仿真结果证明了其有效性.

The spread spectrum （SS） signal modulated by pseudo noise code is typically cyclostationary （CS） signal. Based on the spectral correlation theory of CS signal, a cyclic spectrum detection method of SS signal using acousto-optic （AO） signal processing technique was presented. The cycle frequency and cyclic spectrum of the SS signal as well as AO CS processing model were investigated. Via AO CS time-integrated correlator, the AO correlation function （cyclic spectrum） of SS signal was detected at the cycle frequency. Compared with the conventional signal energy detection methods, the cyclic spectrum detection has better detection characteristic. For noise and interference, no matter what they are stationary or non-stationary, the cyclic spectrum detection is with the quite antiinterference capability. The simulation results show the effectiveness of the method.