Tracking maneuvering targets with multiple sensors using the interacting multiple model algorithm

One of the more difficult targets to track is an aircraft performing high speed maneuvers. The Interacting Multiple Model (IMM) algorithm uses multiple models that interact through state mixing to track a target maneuvering through an arbitrary trajectory. The IMM algorithm provides significantly better tracking results when compared to a single model track filter. To improve tracking performance, multiple sensors can be used to provide more information about the target. Using the measurements from several sensors with a single motion model track filter can provide improved track performance when compared to a single sensor system. Since single sensor track filters use decision-directed approaches for maneuver response, using multiple sensors with a single model track filter would be difficult to implement because periodic measurement updates cannot be expected and the sensors may be dissimilar with different accuracies. Thus a very complex tracking algorithm would be required. While the tracking performance of a single model may improve with additional sensors, it can be erratic for maneuvering targets. Using multiple sensors with the IMM algorithm can improve the IMM algorithm performance without the erratic performance exhibited by single model trackers. Target tracking with multisensor systems is described along with the IMM algorithm. Comparisons of track performance with IMM algorithm and single motion model track filters are presented for several sensor systems.