Patent ID: 6894640

Claim:
A method for processing radar return data in order to reject returns from a negative doppler shift swath to mitigate corruption of returns from a positive doppler shift swath, the radar receiving returns at each of a right channel, a left channel, and an ambiguous channel, said method comprising: sampling the radar data from each of the channels; converting the radar data samples into in-phase and quadrature components; separately filtering the in-phase and quadrature components of the radar data samples; converting the filtered in-phase and quadrature components of the radar data samples to doppler frequency signals, using cascaded second order infinite impulse response filters; separately filtering the in-phase and quadrature doppler frequency signals with band pass filters centered at the doppler frequency; subtracting the quadrature components of the filtered doppler frequency signals from in-phase components of the filtered doppler frequency signals; and determining phase relationships between the right, left, and ambiguous channels using the filtered in-phase and quadrature doppler frequency signal components, the quadrature components subtracted from the in-phase components.