Alpha-beta-tracking index (α-β-Λ) tracking filter

An alpha-beta-tracking index (alpha-beta-Lambda) tracking filter for the single target tracking is proposed for maneuver-following capability. The tracking filter incorporates an estimation technique of the tracking index in the gain approximation algorithm (IEEE Trans. Aerospace Electron. Systems AES-20 (March 1984) 174) and uses a gate-growing method to measure the degree of the target's maneuver. It involves a changeover algorithm which switches over to the conventional alpha-beta filter when the tracking target reaches stationarity, and switches over to the gain approximation algorithm when the tracking target begins to maneuver. The data association algorithm based on comparing matching score makes the gate-growing process reliable in clutter environment and at the same time has the ability of identifying the target, not requiring a separate step. Simulation results show that it is more robust in terms of its ability to minimize the prediction error irrespective of whether the target is in maneuver or not, and whether the target trajectory is linear or not. The proposed alpha-beta-Lambda filter can realize the accuracy of the Kalman filter with an algorithm as simple as the well-known alpha-beta filter. (C) 2002 Elsevier Science B.V. All rights reserved.