【摘要】 由于双线性时频分布(BTFD)对多个Chirp成分信号的时频表示存在交叉项干扰,因而在低信噪比情况下直接在时频平面难于进行检测和参数估计.该文提出了将信号的双线性时频分布作为图像,利用Hough变换检测图像中直线的原理,将多Chirp成分信号的检测与参数估计转换为在参数空间寻找局部极大值及其坐标的问题,可以使得检测和参数估计一并完成.仿真实验表明,该方法不仅能够有效地检测多Chirp成分信号并估计其参数,而且有较高的抗噪声性能,并能起到抑制与信号自项重叠的交叉项干扰的作用.更多还原

【Abstract】 Because of the presence of cross-term interference in bilinear time-(frequency) distribution (BTFD) of multi-component chirp signals, it is difficult to detect the chirp components and estimate their parameters in a time-frequency plane in case of low SNR. In this paper, considering the time-(frequency) distribution as an image and using the Hough transform for straight line detection from the (image,) a novel method is proposed in which the detection and parameter estimation is carried out (simultaneously) by searching the local peak values and their corresponding coordinates in the image. (Simulation) results show that the method is not only effective in detecting and estimating the multi-component chirp signal, but can also suppress noise and cross-term interference.更多还原