一种有效的CFCR域LFM信号分析方法

为了解决现代电子战领域中无延迟的线性调频信号分析方法计算量大,以及低信噪比情况下抗噪性能和估计精度不理想的问题,提出了一种有效的无延迟线性调频信号分析方法。所提算法通过利用局部尺度傅里叶变换和傅里叶变换,将线性调频信号变换到中心频率-调频率的二维域中。在中心频率-调频率域中,线性调频信号的能量得到有效积累,形成易于检测的尖峰。通过检测尖峰坐标,得到信号参数的估计值。为了提高估计精度和降低计算量,采用了双尺度估计策略。仿真结果验证了低信噪比情况下,该算法具有良好抗噪性能和估计精度,并且所提算法计算量小,易于实现。

Effective method for analysis of LFM signals in the CFCR domain

In modern electronic warfare, to solve the problems of high computation cost, poor anti-noise performance, and low estimation accuracy of no delay Linear Frequency Modulation (LFM) signal methods under a low Signal-to-Noise Ratio (SNR), an effective method for analysis of no delay LFM signals is proposed. By using Local Scale Fourier Transform (LSFT) and Fourier transform, the LFM signal is transformed into a two-dimensional domain named the Centroid Frequency-Chirp Rate (CFCR) domain. In the CFCR domain, the energy of the LFM signal is effectively accumulated to form a peak which is easy to detect. By locating the peak, the parameter estimation of the LFM signal is obtained. In order to improve the estimation accuracy and reduce the computational cost, a two-scale estimation strategy is adopted in this paper. The algorithm has low computational complexity and is easy to implement. The simulation results verify that the algorithm has a good anti-noise performance and estimation accuracy under a low SNR.