Accounting for glint in target tracking

Glint is a major error source for radar tracking at short ranges. It occurs because a target is not a single reflector, but is a collection of reflectors. The returns from these multiple sources may interfere, leading to apparent shifts in the target position. Glint is non-Gaussian and correlated in nature, and may even have infinite variance. Previous work on glint includes the use of the score method to reduce the effect of large errors, and the use of filters which account for the correlation. Only limited work has been done using multiple model techniques. The importance of glint in missile applications justifies further work in the area. The work presented here investigated several multiple hypothesis techniques which seemed particularly suited to this problem. One approach was to approximate the error distribution with a Gaussian mixture. This generates a multiple hypothesis filter, where each hypothesis uses a simple extended Kalman filter. This was extended to take account of the correlation structure of the glint. These methods were tested against a fairly realistic representation of glint which provided a stressing test for the filters.