在通信侦察识别中,通信信号的码元速率估计是调制识别和信息解调的前提和基础。针对直接序列扩频信号的伪码码片速率估计问题,提出了一种利用联合循环高阶累积量非对角1-D切片特征参数,对直扩信号码片速率进行盲估计的改进算法。该算法将采样信号不同延时的非对角1-D切片进行联合处理,通过自相关、快速傅里叶变换、求模平方等方法,增强了谱线特征。仿真实验证明,改进算法较2-D切片算法简化了计算,并且在更低信噪比条件下,实现了对无先验信息直接序列扩频信号的码片速率盲估计。
In communication reconnaissance and recognition, the chip rate estimation of communication signals is the primary problem of modulated classification and information demodulation. An improved algorithm based on joint feature of cyclic high order off-diagonal 1 - D slice is proposed for the blind chip rate estimation of DSSS signals. The algorithm is enhanced the spectral by processing the sam- pling signals with united different delay off-diagonal 1 - D slices, and the process includes autocorrela- tion, fast Fourier transform and modulus square, etc. Simulation experiments have proved that, compared with 2- D Slice algorithm the improved algorithm simplifies the calculation and accomplishes the blind chip rate estimation of DSSS signals with no priori information in lower SNR condition.