Detection and Tracking using Wireless Networks

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Accessible communications are becoming an important part of most people's everyday life. Both business and private users increasingly expect to be able to contact people and get information from any location, not just while at the office or workplace. The incredible success of the mobile phone has further increased the expectations of users in this area. To cater for this demand, a new generation of connectivity possibilities based on wireless local area networks (LAN's) named Wi-Fi is being established.Wi-Fi, or Wireless Fidelity allows you to connect to the Internet from your chair at home, a bed in a hotel room or a conference room at work without wires. Wi-Fi is a wireless technology like a cell phone. Wi-Fi enabled computers send and receive data indoors and out; anywhere within the range of a base station. It's several times faster than the fastest cable modem connection and is rapidly being installed in many locations, such as corporate facilities, in airports, hotels, coffee shops and other public areas equipped with Wi-Fi access. Wireless networking is expanding to longer range outdoor systems as well via WiMax. Wi-Fi and WiMax are based upon an Industry standard technology known as IEEE 802. This is relatively easy and inexpensive to implement and is being widely deployed in many public areas and commercial settings. It has been estimated that over 30 million Wi-Fi cards would ship in 2004 illustrating the impressive rate of growth of this technology. Wireless LAN transmissions can thus be viewed as a future, widely available local area signal. Apart from the communications aspect, these signals have the potential to be used for other purposes. Particularly of interest is the possibility of detecting objects and people using the principles of Radar. In conventional Radar pulses are transmitted and received by the same equipment. In its simplest form this allows the user to detect whether a target is present and how far away from the radar it is by the time delay before the pulse is returned. IF the transmitter and receiver are separated then the processing is slightly more complex but the basic principles still apply. Using wireless LAN transmissions for this purpose could lead to the development of a surveillance capability from a ubiquitous and accessible source. All the transmissions would already be available and a relatively simple receiver system could be designed to carry out this task. There are, of course, many problems to be overcome in applying these relatively simple principles in a real world situation. The proposed full research programme will examine the problems in the context of these initial results and aim to demonstrate that a surveillance system based on wireless networks is a viable alternative and addition to existing systems. The integration of this technique with one existing system (video camera) will also be examined. Such a combination could provide a powerful tool to detect for example anomalous or suspicious behaviour. UCl have already started an initial feasibility study of the technique with promising results and basic target detection capability has already been established. This project addresses a completely new area. Successful development of this technology would result in a major advance in local area detection. Such a system would complement ongoing research into other local area detection techniques such as those using mobile phone systems and RFID tagging. This technique could be used for many purposes including improving internal and external security in private and public areas and identification and tracking of goods and people. Particular applications could be in crime reduction, terrorist threat mitigation and stolen goods detection and tracking.