Advanced ESM Angle Tracker. Volume 1. Theoretical Foundations
Khoury, Edward N. · Defense Technical Information Center (DTIC) · 2006
This report summarizes the NRL implementation of a filter used for ESM angle tracking. The filter is an Interactive Multiple Model (IMM) filter that uses three standard Kalman filters as a basis for filtering and predicting emitter bearing angle. Filter selection for the IMM is based on the expected variation of emitter trajectories and the imposed spherical coordinate system. The derivation of the IMM is well documented and is not addressed in this report; only implementation aspects of the IMM are addressed here. The ESM angle tracker was developed to operate with the NRL ESM-ATD, which provides highly accurate but intermittent bearing and elevation reports. ESM parameters are tracked with first-order filters and provide the basis for associating intermittent bearing/elevation tracks in dense scenarios. The tracker is fully automatic, uses sequential Bayesian hypothesis testing for track initiation, and uses maximum likelihood association implemented across all filters to maximize single-event association probabilities.