摘要
检测与估计扩频信号的载波频率是截获扩频通信的重要手段,在分析直扩BPSK信号特点和传统平方载波检测方法的基础上,根据对称相关变换的性质,提出了一种改进的基于对称相关变换的平方载波检测扩频信号检测与参数估计方法。通过平方检测器,信号在载波的倍频处产生离散线谱,检测离散线谱可实现扩频信号的检测与载波估计。为了提高算法的检测性能,通过对称变换,进一步抑制噪声,有效地改善了输出信噪比,实现了低信噪比下直扩信号的检测。仿真结果验证了所提出方法的有效性。
The cartier frequency detection and estimation is the key to intercept the spread spectrum signal. Based on analyzing the characteristics of DS - BPSK signal and the square detector, an improved square detector based on symmetrical correlation function is proposed for detecting and estimating the DS - BPSK signal according to the symmetrical transform performance. With the square detector, the discrete spectrum lines are produced near the two times of the cartier frequency, which can be used for signal detection. In order to improve the performance of the detection, the symmetrical correlation is further used to suppress the noise. By that way, the output SNR and detection performance is improved. The method is fit for the signal detection at low SNR. The simulation proves the validity of the method.
出处
《电子信息对抗技术》
2008年第1期1-4,16,共5页
Electronic Information Warfare Technology
基金
国防预研基金项目(J14105020077)
