Range-based localisation algorithms integrated with the probability of ranging error in wireless sensor networks

In wireless sensor networks (WSNs), location information is regarded as essential information to achieve intelligent monitoring and control. Recently, a large number of rangebased localisation algorithms were proposed. Nearly, all of the algorithms are based on least square method, in which the sum of all ranging error is treated as the performance index. The disadvantage is ignoring the probability characteristics of ranging error. This paper aims to integrate the ranging characteristic to improve the localisation accuracy. First, introducing a probability factor represents the credibility of distance measurement. Then, the probability factor is integrated into the optimised performance index, and the location of unknown sensor node are estimated and calculated. In addition, the method of determining the probability factor of the ranging information is also provided. Finally, we have performed many simulations to validate the performance of the localisation algorithms proposed. Experimental results show that the localisation accuracy is improved.