The Algorithm Research Of DV-Hop Allocation In Intelligent Public Transportation System

With recent advances in sensor technology, low-power electronics, and low-power radio frequency design have enabled the development of inexpensive and low-power wireless sensors network, where each sensor node individually senses the environment but collaboratively achieves complex information gathering and dissemination tasks. Wireless sensor network can be applied to many areas such as military affairs, environmental monitoring, transportation, and become a new research focus in computer and communication fields. Many applications of wireless sensor networks are based on sensor self-positioning. Because of constraints in size, power, and cost of construction of sensor nodes, the investigation of efficient location algorithm which satisfy the basic accuracy requirement for WSN meet new challenge.In the recent investigation the location technology for WSN can be divided into two categories:Range-based approaches and Range-free approaches. Range-based method have better accuracy, but require additional hardware at the sensor nodes, which are nor available on regular application fort of sensor networks. Acknowledging that the cost of hardware requires by range-based solutions my be inappropriate in relation to the required location precision, researchers have sought alternate range-free solutions to the localization problem in sensor networks. Because of the hardware limitations of WSN devices, solutions in range-free localization are being pursued as a cost-effective alternative to more expensive range-based approaches. The range-free algorithm makes no assumption about the availability or validity of range information.The thesis focuses on investigation of DV-Hop algorithm in the environment of traffic road. Based on analyzing of the hop distance of the DV-Hop localization algorithm. Rssi-based and the average hop distance are proposed to solve nodes localization error. Considering the co linearity degree of nodes. Therefore, Hyperbolic is improved in order to enhance WSN’s stability and localization precision. In sensor field, ill-connected node can’t locate accurately by WSN, hence Max method is improved in this paper, which adds new beacon at the point that has the highest measured localization error among all points.Finally, simulation results show that the performance of localization algorithm is significant improved compared with the DV-Hop algorithm.