A three-dimensional HT-TBD algorithm based on dynamic bias compensation under ambiguity of range and velocity

In order to solve detection problem for near-space hypersonic weak targets under ambiguity of range and velocity, a modified triple-stage Hough transform Track-Before-Detect (HT-TBD) algorithm based on dynamic bias compensation is proposed. Firstly, measurements crossing ambiguity intervals found out by hypothesis testing are compensated in range dimension for rebuilding lost spatial-temporal correlativity due to range ambiguity. Then, modified triple-stage HT-TBD approach is carried on for target point detection. Considering that standard three-dimensional HT-TBD brings about huge computational load, to reduce computation cost and ensure detection performance, three-dimensional measurements are mapped into three two-dimensional planes for point selections in every stage by two-dimensional Hough transform. Besides, point selection is employed by a new double integration means of noncoherent integration and binary integration in parameter space to make full use of energy information and decrease impact from strong interference simultaneously. Finally, range difference and median filtering are utilized to resolve velocity ambiguity, followed by managing to estimating high dynamic bias precisely and make compensation for it. Experimental results demonstrate the effectiveness of proposed algorithm.