A wide area, low cost patient location system is proposed that can be effective in quickly locating patients wandering off, such as patients with Alzheimer's. The system will consist of small, low cost, electronic bracelet units and several base stations. Our goal is to achieve an accuracy of 30 meters or less at a range of 6-10 miles using a single 25 kHz frequency allocation. The patient unit will operate for at least 3 months without changing batteries. The proposed effort consists of a design phase followed by a proof of concept demonstration. The demonstration will highlight all critical elements in achieving the accuracy goal, including multipath and in-building effects. In phase II, the proposed technology will be miniaturized and extensive field trials will be conducted. We will be working with gerontology experts to develop a plan for using the new technology to help care givers best deal with the problems of wandering. The proposed technology has a number of additional applications and can be combined with conventional proximity detection systems.
