Research On Reader Network Planning In Wireless Location System

With the high degree of automation increasing, more and more people require intelligent living. With the advent of smart home, intelligent transportation and smart grid, extensive research on wireless location system plays more and more important role. Currently, many location means are used for indoor location system, such as ultrasonic location technology,ultra-wideband location technology, ZigBee indoor location technology and radio frequency identification technology. The study of this paper is RFID indoor location system. Whether RFID technology can be applied in indoor location depends on RFID network planning. There are mainly two kinds of RFID network planning which are readers anti-collision and tags anti-collision. The aim of this study is how to achieve the reader network planning.Current planning mean for the reader network is taking overall aspects into consideration,such as environment, label distribution, distribution of the reader and interference when model, which makes the modeling of complex and not ideal.In allusion to the collision of readers in the RFID network,this paper combines area coverage, intelligent optimization algorithms and graph coloring theory to optimize the network step-by-step. Firstly, use PSO algorithm to arrange the readers without considering the collision of reader. However, the tags should be covered in the reader's radius of any reader. Then according to distribution of obtained reader, get adjacency matrix based on graph theory. Finally, combine graph coloring algorithm to assign the slots of the readers. Optimize step-by-step without taking the engineering economic factors and excessive interference factors into account can make optimize easily, improve the reader reading rate, reduce the complexity of the RFID network planning and improve security and reliability.Firstly, describe the wireless indoor location system in detail from two respects, the principle of location and solver algorithm. And then introduce the structure,working principle and process of the research object in detail. Several models and reader collision models are given later. At the same time mathematical model of research object in this paper is given in this passage.Secondly, describe certainty seamless coverage of area coverage, PSO algorithm,improved PSO algorithm and bacterial foraging algorithm. Then apply these algorithms in first step of RFID network planning,the reader layout. Compare the merits of the results of these optimization algorithms, and give detailed layout of each algorithm.Finally, study graph theory, graph coloring theory and several graph coloring algorithms.Summarize the relevant concept about graph and study on the rules of graph matrix which are used to gain adjacency matrix based on graph theory. Get flow of the maximum degree priority colored graph coloring algorithm used for reader layout. Then obtained slot allocation graph by simulation of graph coloring which regards the reader adjacency matrix as input of algorithm. Thus the second step of RFID network planning is completed.