RFID Reader System Project

As part of the requirements in a junior-level wireless communications course for an Electrical and Computer Engineering Technology program, students are required to design and implement an RFID reader system to record multiple tag IDs. This lab project utilized the ThingMagic M5e-C embedded RFID OEM module. This OEM module was mounted in a plastic enclosure box with an attached antenna and a flexible cable for I/O connections. A printed circuit board was designed to interface the assembly to a standard lab breadboard. The enclosure box, OEM module, PCB, and RFID tags were then provided to each student team. The overall objectives for this lab project included connecting a PC to the RFID module via RS-232 and designing LabVIEW software to control the module. The students were required to configure the RFID module, read 5 tag IDs (using the GEN2 protocol), store the tag IDs to a file on disk, and add header information to the file containing the students’ names and a time & date stamp. A detailed listing of the command and response packets is provided, along with an example of the tag IDs. A summary of the contents of the student reference materials and the lab handout are also included. Assessment results showing grading statistics, lab report format, and grading rubric are provided. An example of a student’s results for the project is shown, and recommendations are included to help ensure student success on the project. Introduction to the Wireless Communications Systems Course The wireless communications systems course is a junior-level course for Electrical and Computer Engineering Technology students, and it is required for students in the Electrical Engineering Technology option and one of several possible technical electives for students in the Computer Engineering Technology option. Course topics include wireless communications technology, transceivers, modulation techniques, serial communications, and applications which consist of Personal Area Networks (PAN) and radio frequency identification (RFID) systems. The students’ background includes LabVIEW with data acquisition (DAQ) devices for the design of measurement systems 1-3 . Additionally, students complete a course on high-level programming applications of object-oriented and procedure-oriented languages for electrical and electronic problem solving. The course is 3 credits and consists of 2 hours of lecture and 2 hours of lab per week. The lab content is designed to reinforce concepts discussed during lecture. Each lab is considered a design project since it contains a series of engineering requirements and takes either 2 or 3 weeks to complete, depending upon the scope of the project. Each project is completed by a student team that consists of no more than 2 students (some students prefer to work by themselves). Students pick their team members at the beginning of the semester. For nearly all of the projects, students are expected to work outside of the scheduled lab time in order to complete the objectives. The grading rubric for each lab project is shown in Table 1. There is a 5% reduction per day for late lab report submittals. P ge 24056.2 Table 1. Lab Project Grading Rubric. Items for Consideration Grade % All the objectives of the lab assignment successfully completed with technically accurate results. 60 Content of lab report 30 Spelling, grammar, and writing style 10 A listing of the projects for the course is shown in Table 2. During the last three weeks of the semester, students complete the RFID reader system design project. The purpose of this paper is to describe the details about the RFID project. Table 2. Lab Project Schedule. Lab # Lab Title # of weeks to complete Lab 1 Signal Generation & Spectrum Analysis 2 weeks Lab 2 Filtering and Digital Graphic Equalizer Design 2 weeks Lab 3 Serial Communication for Voice Transmission 2 weeks Lab 4 IR Telemetry System 2 weeks Lab 5 Wireless Sensor Network 2 weeks Lab 6 Bluetooth-Enabled Instant Messaging 2 weeks Lab 7 RFID Reader System 3 weeks RFID Reader System Design Project The RFID reader system design project consisted of one laboratory exercise, and it was designed to be completed in three weeks. Just prior to this project, students were introduced to RFID technology, RFID standards, and product tagging during the lecture 4-5 . Earlier in the semester, serial communications and communications protocols were covered. For the RFID project, each student team was provided an enclosure box that contained a ThingMagic M5e-C embedded RFID OEM module mounted to the bottom of the box, a flexible flat cable interfaced to a 12-pin 1mm pitch ZIF (zero insertion force) connector on the RFID module, and a half-wave dipole antenna mounted to the side of the box. Additionally, each team received a PCB with a surface mount ZIF connector interfaced to the same flexible flat cable and a 0.1” spacing header that can be used to mount the PCB directly onto a breadboard. An image of the enclosure box, RFID module, and PCB is shown in Figure 1. In order for students to be successful, the lab handout consisted of two sections: an exercise part and a software design part. The exercise part was designed to introduce students to the commands for manually controlling the RFID module. The software design section provided the detailed engineering requirements for the design project. P ge 24056.3 Figure 1. Enclosure Box, RFID Module, and PCB. Exercise Section of the Lab Project Handout For the exercise part of the lab project, the students interfaced the RFID module to the PC RS-232 port. This required them to design the hardware interface that would link the RFID module to the PC's RS-232 port. They referenced the developer’s guide for the RFID module to check the pin-out of the ZIF connector on the RFID module 6 . Then they used an RS-232 transmitter/receiver to convert between the proper voltage levels. An executable LabVIEW RS-232 terminal program was provided which allowed them to send command packets to and receive response packets from the RFID module. Each packet contained HEX values for the data length, command OpCode, and CRC-16 character. Each student team was given 5 squiggle RFID tags and asked to configure the RFID module for the region code and tag protocol, and to read the tag IDs. This portion of the lab could be considered a "spike" solution and allowed the students to verify their hardware interface as well as gain familiarity with the devices operation. A response packet was sent from the RFID module for each command packet it received. Tables 3 and 4 show the configuration for the command and response packets. Table 3. Format of Command Packet. Header Data Length Command Data CRC-16 1-byte 1-byte 1-byte 0 to N bytes 2-bytes Start of packet. Equal to 0xFF Defines the number of bytes N (in HEX) in the data field of the packet Command OpCode (in HEX) Defines the data (in HEX) required for the command Determined by CRC polynomial 0x1021. High byte is first.