Research On Node Localization For Heterogeneous Wireless Sensor Networks

Wireless sensor networks which integrated sensor technology, distributed information processing technology, embedded computing technology, modern network and wireless communication technology, is a hot research field all over the world. Node localization is one of the important issues for wireless sensor networks. Only when we know the position of sensor nodes, can we analyze and process the data reported by the sensor nodes, so as to do further optimization. Heterogeneous wireless sensor network is consisted of nodes with different types. Nowadays, research on heterogeneous wireless sensor networks mainly focused on nodes deployment, routing protocols, topology control, and security mechanism etc. However, the special research on localization algorithm for the heterogeneous wireless sensor network is seldom found.The existing localization algorithm for wireless sensor network which only consider the same type nodes, cannot be directly applied to the heterogeneous wireless sensor network since its node localization algorithm need to consider the different localization mechanism and maximum radius among nodes. This paper research on node localization for heterogeneous wireless sensor networks and put forward a heterogeneous node localization method. Using this method to improve the existing localization algorithms can make them suit the heterogeneous wireless sensor network and improve localization performance.Based on the initial effort in analyzing the problems of wireless sensor network node localization and typical localization algorithms, we summarized the effects of the heterogeneities of heterogeneous wireless sensor network on node localization into three factors:the way of node localization, the mechanism of node localization and the communication radius between nodes. Then we describe the heterogeneous wireless sensor network node localization model and design a heterogeneous node localization method for the model. Using this method to locate the unknown nodes need to use the beacons of same types and different types. This method has the advantage of make full use of beacons resources, reduce cost, improve localization accuracy, can be generalized etc. Then we use this method into the typical localization algorithms and design the heterogeneous centroid algorithm, heterogeneous APIT algorithm and heterogeneous distance algorithm. Finally, we use the MATLAB to build a simulation platform and simulate the localization algorithms which mentioned above on this platform. Simulation results proved that compared to the original algorithms, the improved algorithms more suited to the heterogeneous wireless sensor networks.