Design of Middleware for Using RFID Reader and Tag to Collect Traffic Information Implemented and Tested on Urban-bus for ITS Application

摘要

In this paper, we propose a website to exhibit the traffic information for every 5 minutes at certain places of street measured by three Radio Frequency Identification (RFID) readers for 216 tags installed on two different urban-bus companies and transmit those information via GPRS modem from testing point to control center. Each data can be used to indicate the exact point of traffic condition in a big city. Because the design hardware of reader is not suitable for the purpose of collecting traffic information, one can not adjust its resolution as you like. Thus, the analysis of turning point on the major errors of distance and timing errors is very important to let the system designer to take correct strategies to compensate for all of possible errors. One can conclude the following rule: 1) when speed is fast, timing error becomes dominant; 2) when speed is low, distance error becomes dominant. The result is very valuable for the local government to make a decision on the adjustment of urban-bus for their future use. The result shows that the application of RFID tag and reader is an alternative way to extract the traffic information instead of traditional loop detector. It is suggested that the vehicle speed estimated by 2 tags 1 reader is more accurate than that of by 1 tag 1 reader compared from historical data.