Localization method of wireless sensor network for greenhouse based on genetic BP algorithm

To meet the need of greenhouse mobile node location, a kind of greenhouse wireless sensor network localization method based on genetic BP(back propagation) algorithm was presented. The approach mainly included three stages: path loss index determination, localization model training and unknown nodes positioning. First of all, during the process of anchor nodes communication, path loss parameters could be determined by using minimum mean square error estimation method after applying the gauss correction model to enhance positioning information accuracy; Then, a mapping relationship model between the unknown node coordinate and the distance vector from unknown node to anchor nodes was established by using genetic BP algorith; Finally, the received RSSI value from each anchor node to unknown node could be converted into distance vector, and then entered localization model to estimate the unknown node position. The experiment result showed that the greenhouse wireless sensor network localization method was fully considering the effect of environment on signal transmission model, the localization error rate below 2m was 24%, the localization error rate below 3.5 m was 86% and the relative localization error was less than 4.8%. The method has high ability of stability and precision, and meets the practical need of greenhouse environment localization.