The project 'Tracking and positioning' is a part of a 'Security and Surveillance' system which requires monitoring the positions of security personal within the secured area. The word "security" in general usage is synonymous with "safety," but as a technical term "security" means that something not only is secure but that it has been secured .
The 'Security and Surveillance' system looks to provide all-round security to a restricted area (like a research lab) and also monitor the area round the clock so as to prevent a possible security breach. In this regard the 'Tracking and Positioning' system is of utmost importance as it allows a security official to monitor the position of the other security staff in the secured area and direct them appropriately as and when required.
The 'Security and Surveillance' system aims to provide high end security that involves a sequence of Biometric scanning and RFID based authentication. A secure wireless communication link and a system to track the position of security personal within the secured area are other components of the system that enable to the monitor of the security status of the restricted area.
Since prehistoric times, people have been trying to figure out a reliable way to tell where they are and how to get to their destination and back home again. Such knowledge often meant survival and economic power in society. The systems that intent to use location in order to register user's movement and to use the generated data for extracting useful knowledge define a new area of research that has technological as well as theoretical underpinnings.
Location-based applications encompass a broad range of markets, including entertainment, fleet management, commerce, safety and systems applications. In all cases, maximizing position location accuracy and availability is the predominant requirement.
One of the most straightforward solutions to meet the position location requirements is to use the Global Positioning System (GPS). However it is not an attractive option as the system increases the size and weight of hand set, and also causes drain of battery of hand set. To find the geographical location, the GPS receiver needs to have at least four satellites visible at all times, which is difficult in indoor calls.
Other methods such as infrared (IR) or radio-frequency (RF) beacon tagging overcome this limitation of GPS, but often require the expensive deployment of new infrastructure. Wi-Fi based positioning builds on an already existing, widely available infrastructure and works indoors as well as outdoors.
Another method of positioning is done by signal strength measurements from multiple access points. Since a change in signal strength is correlated to the distance between two stations, the locations can be estimated based on received signal strength indicator (RSSI) values. The system requires minimal setup time compared to other systems, which makes it readily available for real-world applications.
This system gives a course estimate of the position. A much higher accuracy rather insensitive to fading is based on time of arrival (TOA). In future system, only the time difference of arrival (TDOA) or enhanced observed time difference (E-OTD) measurements may be possible to compute.
The project 'Tracking and Positioning' aims to implement tracking to centrally locate the position of a person. The person to be tracked will be tagged i.e. he will have a 'unique' transmitter which would generate signals using which his position is to be tracked.
Stationary base stations, placed appropriately within the secured area would monitor the signals received from the mobile transmitter and use a specific characteristic of the received signals (signal strength, timing delay etc.) to calculate the position of the transmitter within the secured area. The system aims to monitor the position of the tagged personal from a central control room which is to be achieved by providing the data from each of the base stations to a central processing unit that would use these data to simulate the motion of the personnel.