Fuzzy Triangle Localization Algorithm In WSN And Simulated Implementation

The study of localization algorithm that obtains higher efficient and lower energy consumption is very important to wireless sensor network's theoretical study and practical application. The localization algorithm is usually divided into range-based and range-free. Range-based localization algorithm's hardware requirement for positioning device is high, so it does not apply to cost of hardware-constrained confined wireless sensor network. But range-free localization algorithm's hardware requirement is lower, and its localization accuracy has already met the needs of the majority of WSN applications, so it is a kind of cost-effective solutions.According to the idea of fuzzy math, this paper puts forward a range-free localization algorithm-FTL (Fuzzy Triangle Localization); and points out that the algorithm has the characteristics of adjustable localization accuracy. For the shortcomings of FTL's large volume of computation, this paper puts forward IFTL (Improved Fuzzy Triangle Localization). And FTL both belong to the fuzzy triangle localization algorithm. Ensuring localization accuracy, IFTL greatly reduces the volume of computation.After simulation to FTL and IFTL localization algorithms, this paper points out the impact that number of anchor nodes, density of anchor nodes, pass loss exponent shadowing's standard deviation and location of unknown nodes bring to the localization accuracy. Algorithm performance of IFTL is better than that of FTL on volume of computation, on volume of network energy consumption, and on localization delay time. But algorithm performance of FTL is better than that of IFTL on localization accuracy and on anti-interference ability. So, this paper supposes that FTL and IFTL have their own trade-offs and have their own performance characteristics.This paper simulates centroid localization algorithm, convex position estimation, DV-Hop, APIT, SBL, and puts analysis on and comparison to these five classic range-free localization algorithms and IFTL localization algorithm on localization error, network energy consumption, localization delay time, time and space complexities. The simulation result shows, comparison with these five classic range-free localization algorithms, IFTL algorithm has highest localization accuracy, lower energy consumption, shorter localization delay and lower computational complexity. So, we think fuzzy triangle localization algorithm overall performs better. In practical application, we should solve different problems or support different applications according to the features of FTL and IFTL localization algorithms.