Research On Localization Algorithm In Wireless Sensor Network

Wireless sensor networks, as a brand-new technique in information acquisition and processing, can be wildly used in many areas such as national defense, environmental supervision, medical treatment, outer space exploration, counter-terrorism and disaster retrieval. It is considered as one of the most important techniques of the 21st century. But for most applications, data without location information has limited use. Localization has become one of the indispensable supporting techniques in wireless sensor networks, and has widely drawn attention of domestic and foreign scholars.Existing localization algorithms can be roughly divided into two categories: range-based localization algorithm and range-free localization algorithm. For the limitations of battery, cost and volume in wireless sensor networks, the range-free localization algorithm has higher practicability. However, most of range-free algorithms require the beacons to be of high density and uniform distributed, bringing about the cost increasing, aggravating the competition and conflict in communication, and severely limits the application areas of range-free localization algorithm, which is called the beacon scarcity problem.In this paper, with the motivation of solving the beacon scarcity problem, we use only one mobile beacon to constantly broadcast its location in the network, helping the node to make range-free localization. This method decrease the beacon cost to the least, and gets the special distribution of reference positions through controlling the moving route of the beacon, therefore can effectively overcome the beacon sacristy problem. Considering the difference in application scale, we designed a proximity based mobile beacon assisted localization algorithm (PMALoc) for the application of small scale, and designed a distance-in-hops based mobile beacon assisted localization algorithm (HMALoc) for the application of large scale.We have analyzed and compared in theory the energy consumption of algorithms proposed in this paper and similar kind algorithms using static beacons, and both of the algorithms have lower energy consumption. To further validate the practicability of the algorithms proposed, we examined the...