Evaluating context based indoor positioning system using Wi-Fi standards

Context-aware computing is an emerging computing paradigm that can provide new or improved services, which are human centered and proactive in responding to the surrounding environment by exploiting user context information. There are many applications that provide context-aware services based on the location of the user. This paper proposes the implementation of Wi-Fi based architecture for location estimation and navigation system, which is cost-effective by employing existing IEEE 802.11 network infrastructure available in many office and home environments. The proposed approach can provide meter level accuracy, which is sufficient for most location-aware applications. The positioning system is deployed to estimate the present location of the computing device such as a PDA by approximating the relation between improved Received Signal Strength Indicator (RSSI) values and relative distance between the sender and receiver. It makes use of Modified Kalman Filtering which processes the available measurements, to estimate the current value of user's position. Using the location information obtained and the inputs from the user, positioning system navigates the user to desired destination. Thus the proposed system is able to position the user in a complex indoor environment with improved accuracy.