A study of the G-H-K tracking filter, volume 1

This report is concerned with the investigation of the G-H-K filter for tracking maneuvering targets. The selection of the filter coefficients is based on the amounts of noise and maneuver, and other system considerations such as critical damping or best transient response for specified smoothing. Several filter initialization schemes were tested. For low acceleration maneuvers, a considerable amount of smoothing can be achieved without losing track. However, in order to track severely maneuvering targets, one must select coefficients which give a faster transient response at the expense of smoothing capability. Therefore, it is logical to use an adaptive filter with a good smoothing capability when the target is not maneuvering and a fast response during a target maneuver. Clearly, the main problem is to detect the maneuver in a reasonable amount of time. This can be done using a simplified matched filter followed by a threshold detector. The proposed adaptive filter was evaluated through computer simulation using typical trajectories. The performance of the adaptive filter is limited by the number of samples required by the detection filter and could probably be improved using a more complex maneuver detection filter.