Positioning Algorithm Based On DV-Hop In Wireless Sensor Network

With the rapid development of science and technology in today’s society,wireless sensor network has been widely used in every field of human daily life andsocial activities. Positioning technology plays a crucial role for wireless sensornetwork. If there are some available position informations, many new applicationsabout wireless sensor network can be developed. The most common locationalgorithm bases on whether need to range or not, the algorithm is divided intorange-based technology and range-free localization algorithm. Since range-freelocalization algorithm requires a small hardware cost and can be easy to realize, it is ahot spot and focus in the research.This paper is mainly research on range-free DV-Hop localization algorithm.Firstly, it analyzes the DV-Hop algorithm principle, and points out the defects of thealgorithm, then analyzes some existing improved DV-Hop algorithms. Secondly,according to the large positioning error, the defect of low coverage when the anchornode scale is smaller in classical DV-Hop algorithm, the paper proposes a newalgorithm called IDV-Hop (Improved DV-Hop).IDV-Hop algorithm is mainly improves in three aspects:①Fixed average hopdistance. Using the mean of whole network average jump distance and single anchornode average jump distance to replace the classical DV-Hop average when in theuneven distribution network, the estimated value of the average jump distance notonly can reflect the whole network average jump from the overall situation, but alsocan reflect single anchor node estimated jump distance from the local situation, thusthe average jump distance value is more close to the real value.②Select the bestanchor nodes combination to locate. Anchor node position information has a biginfluence on final unknown node coordinates calculation. According to the differenceof the unknown node to anchor node connectivity, IDV-Hop algorithm selects the bestthree anchor nodes group to calculate the unknown node coordinates, thus thecalculated average hop distance will be more accurate.③The unknown nodeupgrades to anchor node. The number of anchor nodes plays a key role on the networkcoverage rate, IDV-Hop algorithm upgrades the maximum Priority Pri value ofunknown node to auxiliary anchor node. The auxiliary anchor node and originalanchor nodes broadcast information again, then choose the maximum value of thereordered unknown node Priority Pri. The located unknown node of maximumpriority Pri value upgrades to auxiliary anchor node again, until all the unknown node positioning are finished by such circle. So, the anchor node can cover more unknownnode, and thus improve the network node coverage. Lastly, the improved algorithm iscompared to classical DV-Hop algorithm with the MATLAB software, The simulatedresults show that the IDV-Hop algorithm are superior to the classic DV-Hop algorithmin the location accuracy and coverage rate.