Radar system for detecting close range of targets using frequency-modulated continuous wave and stepped frequency waveform and method of detecting same

摘要

The elimination technique of the present invention is implemented in a system, and a radar signal processing method is used to detect near range targets. The present invention uses frequency modulated continuous wave (FMCW) or stepped frequency waveforms and is capable of detecting proximity targets that are generally ambiguous due to transmitter leakage and internal influences. This cancellation technique operates by transmission of one or more reference ramp signals and then subtracts the coherent average of the reference ramp signals transmitted from one group of successively transmitted and received ramp-down signals. The last group of FM ramp return signals are non-coherently integrated to achieve more stable target detection statistics. In particular, the technique according to the present invention comprises the following processing steps: generating a plurality of predetermined reference ramp signals, coherent averaging the target return signals corresponding to the transmitted reference ramp signals to generate a reference average signal Subtracting a reference average signal from each lamp return signal to produce a removed ramp signal, Fourier transforming each of the stored ramp signals, calculating a magnitude of the Fourier transform signal Performing a non-coherent integration of the magnitude detected signal, thresholding the integrated signal, centroding a thresholded signal indicative of a range for a target with the centroid location closest to the target, And displaying target data for a target that is smaller than the selected money blocking range.