通信侦察中一种新的码速率盲估计方法

Blind estimation of symbol rate in communication reconnaissance

在截获信号调制样式未知的情况下,提出了一种码元速率估计方法。把正交解调后的I路或Q路信号延迟相乘自相关后,通过在频域测量与码元速率对应的谱线来估计码元速率。仿真结果表明,该算法即使在很低信噪比情况下,也不受脉冲成形滤波器及其系数的影响,具有很好的稳健性。该方法为码元速率估计提供了一种新的思路。

A method of symbol rate estimation is proposed without the knowledge of signal modulation type. After multiplying the in-phase component or the quadrature component of the intercepted signal by its delay, the autocorrelation will be estimated. As a result, in the frequency domain, the discrete spectral lines occur at the location which is corresponding to the symbol rate. The symbol rate can be quickly estimated by detecting the location of the discrete spectral lines. Simulation results show that the method is immune to pulse-shaping filter and its parameter in the condition of low SNR. The method provides a new idea to symbol rate estimation.