Research On Localization Algorithm Based On Signal Strength

Wireless Sensor Networks (WSN) is integration of sensor techniques, nested computation techniques and wireless communication techniques and so on. It is considered as one of the most significant emerging technologies in21st century.Position technology is the key technology of Wireless Sensor Network,which makes many experts and scholars at home and abroad attracted.The paper introduces the classification of the positioning algorithm and the positioning algorithm based on signal strength, also the performance evaluation of wireless sensor networks algorithm,propose the model for location algorithm. Mainly analyse three-border measurement based on signal strength and scheme of the location algorithm.The CC2431,RADAR and Calamari location system are introduced in detail.The wireless experiment platform is designed.The positioning nodes determine their positions used signal strength sent by reference nodes through three-border measurement.Three-border measurement based on the signal strength is realized on CC2430module with wireless locating codes written into SmartRF04EB and CC2430of TI company,which is used to measure in the actual environment.The floating-point numbers in the algorithm formula can not be displayed right,which leads to substantial errors.An improved algorithm for the algorithm of three-border measurement based on the signal strength is discussed and proposed by phenomenon in the experiment.A mapping table that reflects the relation between RSSI and d is list.Datas in experiments show that the improved algorithm has higher precision of positioning.The algorithm effectively solve the short precision problem and so on,simplify the algorithm and reduce the cost for node operation.