The above titled paper was mistakenly omitted from the June 2010 JSAC issue (Vol. 28, No. 5) on Mission Critical Networking and appears here in its entirety.

Wireless sensor networks (WSN) have thus far been used for detection and tracking of static and mobile targets for mission critical surveillance applications. However, detection and tracking do not suffice for a complete and accurate target classification. In fact, surveillance target imaging yields the most valuable information. Current techniques mainly aim to provide images of static environment in a sensor network. Nevertheless, imaging of mobile targets requires networked and collaborative detection, tracking and imaging capabilities. With this regard, ultra-wideband (UWB) radar technology stands as a promising approach for networked target imaging due to its unique features such as having no line-of-sight (LoS) requirement. However, UWB wireless radar sensor network (WRSN) is yet to be developed for imaging of mobile targets. In this paper, an architecture and a new collaborative mobile target imaging (CMTI) algorithm for WRSN are presented. The objective is to efficiently obtain an accurate image of mobile targets based on the collaborative effort of deployed radar sensor nodes. CMTI enables detection, tracking and imaging of mobile targets as a complete WRSN solution. Performance evaluations reveal that CMTI yields high quality radar image of mobile targets inWRSN with very low communication overhead regardless of the target shape and velocity.