Multiple target tracking based on symmetric measurement equations

An approach to track maintenance in multiple target tracking is presented in terms of measurements which are symmetric functions of target positions. In this approach, the data association problem is embedded in the process of target state estimation so that there is no need to consider possible target/measurement associations. For N targets moving in three-dimensional space, the first-order version of the target state estimator is an extended Kalman filter of dimension 6N. Attention is focused on the case of constant-velocity targets with the number of measurements (of a given coordinate) assumed to be equal to the number of targets