Adaptive two-time-scale tracking filter for target acceleration estimation

TLDR: A new tracking filter is presented that copes with the problems associated with the synthesis of target trackers for air-to-air missiles and is based on the time scale separation inherent in the tracking dynamics.

Abstract: A critical phase during air-to-air interception is the homing phase. It is characterized by a short time to go and low bearing rates on the homing path. The phase is critical because any misconception with respect to the target maneuver may result in a substantial miss distance. This is essentially due to the lack of time to perform path corrections when the target produces a collision course error by an evasive maneuver. The estimation of the target acceleration is therefore crucial to the design of guidance laws that allow a fast response to target maneuvers. There are, however, severe problems associated with the synthesis of target trackers for air-to-air missiles. These problems include the lack of observability, modeling errors, and the restriction of the computation time due to high sampling rates. In this paper, a new tracking filter is presented that copes with the problems just mentioned. It is based on the time scale separation inherent in the tracking dynamics. In conjunction with a simple adaption scheme, this filter is able to track a large class of target maneuvers in a computationally efficient manner.