US Patent 11467242 Direction-of-arrival estimation apparatus, method, and non-transitory medium

A direction of arrival estimation apparatus includes at least first and second sub-arrays to receive a reflected wave of a transmission waveform from a target; first and second phasing parts that perform phasing of reception signals at the first and second sub-arrays to generate first and second sub-array beams; an arrival time difference calculation part that calculates first and second correlations of the reception signals of the first and second sub-array beams at first and second time points to find an arrival time difference between times of the reflected wave arriving at the first and second sub-arrays, based on a result of a predetermined operation on the first and second correlations and a time difference between the first time point and the second time point; and a direction of arrival calculation part that finds a direction of arrival of the target based on the arrival time difference.