Track-before-detect of weak ballistic target using elliptical Hough transform

A track-before-detect (TBD) algorithm based on elliptical Hough transform (EHT) is presented for jointly detecting and tracking weak ballistic targets during its exoatmospheric flight. The new method makes use of the fact that the ballistic target follows the elliptical orbit when restricted to two-body problem. The relationship between raw radar measurements in the data space and the elliptical parameters in the parameter space is established with coordinate transformations. The EHT detection algorithm is designed and the orbit planarity is also considered to reduce the noise accumulation effect. The detection performances related to primary and second thresholds and signal-to-noise ratio (SNR) are analyzed and verified through simulations. The advantage of the new method lies in it can not only detect and track weak ballistic targets but also can predict the impact point by using available parameters.