An Improved APIT Algorithm Based on Direction Searching

Nowadays, wireless sensor network can be widely used in the military field, precision agriculture, environmental monitoring, intelligent home environment, urban transport and so on. As a core support technology of it, self-location node technology is the basis of most practical applications in WSN. Sensor's self-location methods can mainly be divided into two categories: range-based algorithm and range-free algorithm. In this paper, taking into account of the low positioning accuracy in the location-free APIT algorithm as a result of the sparse anchor nodes, we bring forward an improved APIT algorithm based on the direction searching. Simulation results show that by searching for the reliable direction, compared with the original APIT algorithm, the improved one can significantly improve positioning accuracy, with a higher reference value.