Research On Wireless Sensor Network Localization Algorithms Based On Dv-Hop

Wireless sensor networks is composed of many sensor nodes which are deployed in acomplex area beyond men’s approach by means of scattering randomly to collect andtransmit the data. Observers can acquire the fruitful answer quickly and directly, andwireless sensor networks perceive, collect and process the monitoring information of thetarget in a network area cooperatively. Node localization is the indispensable theoreticalfoundation and important link that attracts the attention of many scholars. Refer to datamonitoring, data control and wireless communications in wireless sensor networks, theposition information of an object is very important and the researcher’s work does notmake sense without corresponding position information. As a result, how to locate thegeographic information of the target to be monitored accurately has become a hot topic inthe research of wireless sensor networks.Range-based and range-free localization algorithms are applied more widely thanother localization algorithms of wireless sensor networks. Range-based localizationalgorithm needs the support of external hardware devices, while range-free localizationalgorithm is relatively simpler which has the lower cost and can estimate the locationinformation of the unknown node simply by network connectivity. At present, the DV-Hoplocalization algorithm has become a typical and active algorithm with a larger researchvalue due to low-cost without ranging and easier to develop. This article makes an in-depthstudy in the principle and the shortage of the DV-Hop localization algorithm mainly basedon the localization algorithm for wireless sensor networks and expand the discussion andperformance analysis of the algorithm by studying and comparing the improved DV-Hopalgorithms. The innovation of this paper lies in the following three aspects.1. The error sources of the DV-Hop localization algorithm were analyzed by summingup a mass of improved and optimized DV-Hop algorithms. The objective factor thatcaused the error was result of the uneven node distribution and the bad node in the network,what is more, the proportion of anchor nodes and neighbor nodes in the network.While thenumber of hops, average hop distance estimates and the error of location calculation alllead to the subjective factor. The performance index of DV-Hop localization algorithm canbe simulated objectively by means of the simulation experiments, including the nodedistribution in the network, the network connectivity and positioning errors.2. Particle swarm optimization for nodes localization algorithm in WSN based onhopping distances error-weighted was presented, namely WPDV-Hop localization algorithm. The improvements of this algorithm lied in the following three aspects aimingat reducing error sources of DV-hop localization algorithm. At first, limited the scope ofbroadcasting the data packet of anchor nodes. Secondly, calculated the average hopdistance error of anchor nodes, and estimated the average hop distance based on theerror-weighted according to this value. Finally, optimized the positioning nodes using animproved particle swarm algorithm. Simulation results show that the WPDV-Hoplocalization algorithm has better positioning accuracy and algorithm stability comparedwith the original algorithm, and reflects the actual state of the entire network better basedon these improvements.3. Location judgement for nodes localization algorithm in WSN based on hoppingdistances error-modified was presented, namely WLDV-Hop localization algorithm. Theimprovements of this algorithm lied in the following two aspects aiming at reducing theerror caused by the randomness of the anchor nodes and the error in the estimates of theaverage hop distance in the DV-Hop localization algorithm. At first, adopted the locationjudgement to select the best anchor nodes in the trilateral positioning method. Secondly,calculated the average hop distance according to the average hop distance error and thehop between the unknown nodes and anchor nodes. Simulation results show that theWLDV-Hop localization algorithm solves the problems in trilateral positioning effectivelywithout increasing the external overhead, and improves the positioning accuracy of thenodes.