The Research Of Range-Based Localization Algorithms In Wireless Sensor Network

Wireless sensor network (WSN) has received increasing attention in recent years, which has wide applications in the aspects of industry, military, and environment. Knowledge of nodes location is an essential requirement for many applications. Without location information of sensor nodes, the sensed data or the detection of events is nonsense.This paper introduces the classification and the developing situation of location technology in WSN. Some classical localization algorithms and its advantages and disadvantages are introduced in details. By analyzing the localization principle, the localization process is divided into two phases:the ranging phase and the localization phase. In the ranging phase, considering the tendency of small volume and low power, the RSSI ranging technology is taken. As environmental factors have a large impact on RSSI ranging accuracy, this paper discusses the RSSI value of the abnormal processing, and puts forward a set of online modeling and error compensation method.In the localization phase, analyzing the classic trilateral localization algorithm, This paper put forward ill-condition equations in trilateral localization algorithm for the first time. Trilateral location algorithm based on the minimum condition number is presented innovatively.Many ranging and localization experiment are conducted. We draw a conclusion:RSSI value is highly affected by the environment, and the3σ method processing, on-line modeling and error compensation can effectively improve the ranging accuracy. On the other hand, the proposed trilateral localization algorithm based on the minimum condition number in this paper has a good performance than the classical nearest trilateral localization algorithm in localization accuracy, which provides the basis in theory and in practice for the optimization of the trilateral method.