一种未知脉冲信号检测与瞬时频率高精度估计方法

A method for unknown pulse signal detection and high-precision instantaneous frequency estimation

针对未知脉冲信号检测与瞬时频率估计问题,提出了一种基于瞬时频率高精度估计的联合检测方法.在瞬时频率高精度估计中,采用快速傅里叶变换分析与陷波滤波器相结合,实现对未知信号瞬时频率高精度估计.在未知脉冲信号检测中,采用能量累积法和瞬时频率方差法相结合方式,综合瞬时频率方差检测器和能量累积检测器的优势,可对未知脉冲信号实现有效检测.结果表明,在一定信噪比条件下,本文方法可以实现对未知脉冲信号瞬时频率的高精度估计,瞬时频率估计方差接近克拉美罗下界,估计精度提高了0.1%,同时实现了对窄带和宽带未知脉冲的有效检测.

In order to solve the problem of unknown pulse signal detection and instantaneous frequency estimation,a joint detection method based on high-precision instantaneous frequency estimation was proposed.In this high-precision instantaneous frequency estimation,fast Fourier transform(FFT)analysis and notch filter were combined to achieve high-precision instantaneous frequency estimation of unknown signal.In the unknown pulse signal detection,the combination of energy accumulation and variance-of-instantaneous-frequency(VIF)methods was employed,the advantages of VIF and energy accumulation detectors were integrated,thus the effective detection of unknown pulse signal could be achieved.The results show that at a certain signal to noise ratio(SNR),the proposed method can realize high-precision instantaneous frequency estimation of unknown pulse signal,the VIF estimation is close to Cramer-Rao lower bound(CRLB),the estimation precision gets improved by 0.1%,and the effective detection of unknown pulse signal at narrow and board bands can be completed at the same time.