Relative Accuracy based Location Estimation in Wireless Ad Hoc Sensor Networks

In sensor networks, the location of a sensor making an observation is a vital piece of information to allow accurate data analysis. GPS is an established technology to enable precise position information. Yet, resource constraints and size issues prohibit its use in small sensor nodes that are designed to be cost efficient. Instead, most positions are estimated by a number of algorithms. To date, however, the focus was on individual accuracy of each sensor´s position estimates in isolation to the complete network. In this paper, we propose a novel positioning algorithm called nQUAD to enable representative topology information based on relative accuracy. nQUAD makes use of relative distances to determine the quadrant it resides in and refines its estimation according to neighbor provided information and reports a level of certainity along with estimates. Our experiment results suggest significant improvements in individual accuracy in comparison to lateration based alternatives. At top of all, drastic improvements are achieved in the overall topology to enable accurate analysis of data.