Improved Dv-hop Algorithm Applied Research, In The Random Sensor Networks

With the deep study of wireless sensor network technology, many protocols and applications of information location-based have been out, which made the location technology become one of the main supporting technologies of wireless sensor networks. According to whether need to measure the physical distance between the nodes, positioning technology can be divided into: range-based localization algorithm and range-free localization algorithm. If the distance or angle between the nodes need to be measured, the algorithm is range-based localization algorithm, and if only according to network connectivity information can estimate the position of unknown nodes, the algorithm is range-free localization algorithm.In positioning technology DV-Hop as an range-free localization algorithm is widely used. But the disadvantage of this algorithm is to replace straight-line distance by using hop distance. The higher positioning accuracy can only be found in a dense isotropic network. There is a big error in the randomly distributed wireless sensor networks.This paper mainly studied the application of range-free wireless sensor network localization algorithms DV-Hop algorithm (Distance vector-hop) in the random sensor networks. By analyzing the reason of larger positioning error in random sensor networks, this paper proposes an improved DV-Hop localization algorithm WDH + DAH. Improved algorithm takes the effects which hop count and the average hop distance has made on positioning accuracy into consideration. In the steps number of obtaining hops count, people can take hop count increment as integer 1or decimal according to the different levels of signal attenuation from sending node to receiving node. Weighted variable average hop distance can be used when people calculate distance. Thus people can get a more accurate calculation distance form the unknown node to the beacon node and finally improve positioning accuracy.This paper analyzes the original algorithm and improved algorithm by simulation. The simulation results show the improved algorithm can greatly improve the random sensor network node positioning accuracy based on a slight increase in node energy consumption.