Radar target discrimination by spectrum analysis

摘要

A method for distinguishing between a target and clutter analyzes frequency components of returned wave energy to detect target energy characterized by being present in a narrow range of frequencies, by increasing in the range over time, or by remaining substantially in the range over time. The method utilizes time sequential spectra of the returned energy. The spectra may be signals from a plurality of band pass filters or may be a spectrogram. The energy in adjacent band pass signals and spectra frequencies are correlated to detect energy in a narrow range of frequencies. Differences in successive spectra are integrated to detect increasing energy in a range of frequencies. An energy peak detected in a narrow range by correlation is integrated to detect that the peak remains in the range. The method is adapted for use with a network having inputs receiving successive samples of the returned energy and having outputs individually connected to the inputs through multiplier elements providing selectable factors, a summing element, and a selectable and generally sigmoidal activation function.