The small, portable imaging prototype system weighing 17 lbs. is capable of being quickly deployed. It can be operated remotely through either a wired or wireless Ethernet link under battery power for 2 hours. Control and display functions are performed by an off-the-shelf laptop computer. Tests of the system have established that it is capable of imaging the interior of a building and detecting motion through multiple internal walls and reinforced concrete exterior walls from a range of 30 meters. The development of this "through-the-wall" imaging sensor consisted of two phases. In phase 1 a significant benefit in radar H/W and S/W design was achieved by leveraging prior and current efforts of the grantee. A baseline radar imaging system was designed, and its performance was assessed during laboratory testing. One critical area identified in phase 1 was the potential program risk of FCC certification. Phase 2 leveraged phase 1 results in system design, performance, cost reductions, FCC certification, and law enforcement practitioner evaluation. Technology results included multiple sensor performance; system and radar cost-reduction analysis; and exploration of alternative FCC certification options. Upon completing phase 2, an imaging sensor had been developed that meets operational needs for law enforcement tasks. 18 figures and 5 tables