Range‐spread target detection using time delay‐frequency matched filter

Abstract

A novel time delay-frequency matched filter (t-f-MF) of a mixer output is presented in this study and it is used to design a new range-spread target detector in the background of white Gaussian noise. First, the mixer output of a target is proved to be composed of several sinusoidal signals, and then the matched signal of the mixer output is constructed. Next, the authors use the matched signal to obtain the t-f-MF of a mixer output. The energy of the t-f-MF for the target signal concentrates around zero frequency, whereas that for the white Gaussian noise spreads over the entire frequency domain. According to this, the authors design a range-spread target detector that is capable of detecting a target with high velocity. The proposed detector is evaluated by measured radar data. Experimental results show that the proposed detector outperforms the conventional detectors. The results also show that the detector is robust against the target gesture.