METHOD OF SELECTION OF SURFACE TARGETS Russian patent published in 1997 - IPC

FIELD: radar engineering; applicable in coherent-pulse radars intended for ship handling and aerospace reconnaissance of ships. SUBSTANCE: in the first stage of selection coherent radio pulses are radiated at a constant carrier frequency, reflected signals are received, complex signal envelopes are filtered in Doppler frequency for each range resolution element into M equally spaced frequency components, their power is measured, the measurement results are compared with the threshold level, preliminary decision on existence of a signal from a true target is taken; if the powers of at least one but not more than K adjacent frequency components exceed the threshold level, the second stage of selection is started, in which coherent radio pulses are radiated during n repetition periods at carrier frequency f_i returned from period to period by m values, reflected signals from targets taken as true ones in the first stage are received, procedure of coherent processing and filtration in Doppler frequency of the complex envelope is accomplished at each of m carrier frequencies in m channels respectively, the maximum value of power of frequency components in each of m channels is determined, normalized average value of modules of differences of the maximum values of frequency components is determined by mathematical dependence, compared with the threshold value, if it exceeds the threshold value, a final decision on existence of a signal from a true target is taken. EFFECT: facilitated procedure. 1 dwg