This Small Business Innovation Research (SBIR) Phase I project will investigate the rapid deployment of wireless networks for the purpose of device-free localization (DFL) in tactical through-building surveillance applications. DFL locates people inside of a building using only simple radio devices deployed on the outside of the building. In a police or military operation, these devices are thrown or launched around the building, and then measure the received signal strength (RSS) between many pairs of devices. Within seconds of deployment, the DFL system shows a map tracking people and objects within the building. Such a system requires rapid deployment techniques and real-time operator-free network configuration. This project will advance the state-of-the-art in self-configuring and adaptive wireless networks. Methods for using reconfigurable antennas to direct the antenna pattern through the building regardless of how a sensor lands will be developed. For operator-free deployment, the network will have devices which self-localize, and learn the statistics of the particular radio channels to be measured. The combined results will show that tactically deployed wireless devices can be used to rapidly obtain intelligence regarding occupants before entering a dangerous building.
The broader impact/commercial potential of this project are significant, as lives are lost every year because law enforcement officers do not know what is happening on the other side of a wall. If successful, this project will enable a product for police/SWAT and military special operations forces (SOF) which will save lives by providing actionable intelligence prior to entering a dangerous building. Existing radar technology for through-wall imaging is too expensive ($100k) for all but the most cost-insensitive applications. We plan a product that, because of its low cost, small size, and ease of use, will be standard equipment in police departments and in SOF teams. We will thus capture a portion of an $78 billion surveillance equipment market, which is growing at a 10-13% annual rate. Development of rapid deployment technologies for wireless networks will benefit a wide range of environmental monitoring and "internet-of-things" systems.
This SBIR Phase I project has developed and tested a prototype through-wall localization system for use by emergency personnel who need to find where people are in a building before they enter the building. The prototype system would be used in an emergency as follows. First, when emergency personnel arrive, they would stick hockey puck-sized transceivers to the outside wall, or throw transceivers around the outside of a building. These transceivers would automatically form a network, estimate their own locations via GPS and pairwise measurements, and then start to make measurements between transceivers of the change in the radio signal strength (that is, the number of bars) between every pair of transceivers. A laptop, tablet, or smart phone in range listens to the collected data and computes and displays an image map showing where in the building the people are located. Knowing where the people are will help SWAT team members or firefighters protect their lives and the lives of the people in the building. Although military technology exists to see through walls, this product will be significantly less expensive and show motion across an entire building, not just through one wall. The broader impact is that such a system could become standard equipment in emergency response across the nation, thus creating the situational intelligence that can save lives in dangerous situations. In this project, our intellectual merit is that we have made significant steps toward such a system, and in particular, one that can be deployed quickly. We developed an improved imaging algorithm, and successfully demonstrated its use at several building sites. We showed that GPS is sufficient for the level of transceiver self-localization accuracy required. We showed that a house could be accurately monitored with as few as ten transceivers. We quantified the improvements possible when using directional antennas. Finally, we held a live demonstration of the prototype system at a house in Salt Lake City, and had SWAT and police members present testing the system and seeing how well it worked. All signs indicate that the technology can achieve the necessary performance, and market truly needs this product and will adopt it at the price which it could be sold.
