Literature Survey for Source Localization in Wireless Sensor Networks

Source localization has been one of the central problems in many fields such as radar, sonar, telecommunications, mobile communications and sensor networks. A common technique for source localization is to utilize signal strength measurements of the emitted source received at an array of spatially separated sensors. The received signal strength (RSS) information defines a set of circular equations from which the source position can be calculated with the knowledge of the sensor positions. But in the conventional methods, shadow fading is the major challenge, which corresponds to multiplicative measurement errors. In order to overcome this shadow fading problem, two linear least squares (LLS) estimators are proposed in this project. The first one is a best linear unbiased estimator while the second is its improved version by exploiting the known relation between the position and range estimates. By using the two estimators, we can get the accurate location of the source.