A particle filtering algorithm for cooperative tracking of nodes in wireless networks

Tracking nodes in a wireless network is beneficial for many applications. This is, however, a challenging task in multihop networks, particularly when combined with the limitations in processing power and communication capability of the nodes. The task is further complicated when rapid deployment of the network is required. In this paper we present a new algorithm for cooperative tracking of nodes, which allows accurate tracking over large indoor areas using only a small number of anchor nodes. The proposed algorithm is based on the multiple model particle filter and addresses several tracking issues not previously addressed in the literature. Further, we present a new indoor ranging error model based on our measurements that is simple, yet widely applicable, and gives much better localization accuracy compared to the standard Gaussian error model. Experimental results using a deployed wireless network, where GPS referenced nodes are used as anchors, demonstrate the effectiveness of the proposed algorithm.