Research On The Indoor Positioning Algorithm Based On RFID Technology

At present, the IOT (Internet Of Things) boom is sweeping all over the world. As aresult, the related technologies are developing rapidly through this precious opportunity.RFID (Radio Frequency Identification) technology is the cornerstone of the IOT. Due toits special advantages of non-contact, multi-objective, non line-of-sight, fast recognitionand high efficiency, RFID has become the research focus at home and abroad.Along with the rapid development of the mobile telecommunication network andmobile Internet, in today’s era of global village, the position information plays asignificant role in the fast-paced society. At the same time, it has a huge impact on thesurveillance of the IOT. The indoor positioning, as the hot spot in wireless positioning,not only changes people’s way of life, but also affects the life quality. Being regarded asthe shining star, RFID is becoming the most popular indoor positioning technologybecause of its unique characters. Therefore, the research of indoor positioning based onRFID technology has a great value in the theoretical research and practical application.The thesis introduces the working principle of a RFID system firstly. Then it has abrief introduction of the reader and the tag, which are the main components of thesystem. After that, the application examples and characteristics of RFID technology areshowed; meanwhile, RFID technology development trend is forecasted. Then this thesisputs focus on the classic LANDMARC (the LocAtioN iDentification on the dynaMicActive Rfid Calibration) nearest neighbor positioning algorithm and VIRE (VirtualReference Elimination) algorithm which are based on the received signal strength. Theirprinciples, advantages and disadvantages are analyzed respectively. On this basis, weacquire the essence of these two classic algorithms: nearest neighbor reference tagsfrom LANDMARC, the idea of building virtual reference tags from VIRE. However, alarge amount of unnecessary calculation occurrs when regarding all the reference tags asthe choice of the nearest neighbors in LANDMARC algorithm. An improved algorithm,RFID indoor positioning algorithm based on the space division of virtual grid, isproposed. This improved algorithm divides the positioning space into different subspaceareas in advance, according to the reader’s position, number and different effectivereading range. Thus it lessens the influence of the readers and the reference tags far from the tags to locate. Besides this, the method builds the space division of virtualgrids and selects nearest neighbors dynamically to get the position of the undeterminedtags.The simulation results show that the positioning precision of the improvedalgorithm is higher than the LANDMARC algorithm without any increase of realreference electronic tags. In addition, it has a better stability, more concentratedcumulative error distribution and stronger environmental adaptation ability. Inconclusion, the improved algorithm can obtain an ideal positioning result.