BY CAROLYN MATHAS
The use of RFID and NFC technology to access and share data is finally coming into its own, with the technologies, number of devices, and the killer applications ready to use them. These technologies are not new. Radio-frequency identification (RFID) consists of a small chip and an antenna that is used like a bar code and magnetic strip to provide a unique identifier for an object that must be scanned to retrieve data. Near-field communication (NFC) allows devices to communicate via radio signals when they are used in close proximity or by touching two NFC-based devices together. RFID and NFC both use radio signals to transmit information.
RFID was first used in World War II when it was noticed that when pilots rolled their planes reflected radio signals were altered. The British also created a friend-or-foe identity system by using a transmitter on a plane that broadcast a signal in response from a radar station on the ground, identifying the plane as friendly.
Post-war, early anti-theft systems confirmed payments were made. In 1973, Charles Walton, a California entrepreneur, received a patent for a transponder that unlocked a door without a key. In the 1970s, Los Alamos National Lab was asked by the Energy Department to develop a system for tracking nuclear materials. That system was eventually commercialized in the form of an automated toll payment system that is now used on roads, bridges, and tunnels worldwide. Los Alamos also developed a passive RFID system that used UHF radio waves to track cows to make sure they received the correct dosage of hormones or medicines. Intel recently developed a platform that placed UHF RFID into consumer electronics, embedding RFID functionality.
An RFID system has three parts: a scanning antenna, a transceiver with a decoder to interpret data, and a transponder (the RFID tag) that is programmed with data to be read. When an RFID tag passes through the field of a scanning antenna, it receives an activation signal from the antenna and the chip wakes up and transmits the data, which is picked up by the antenna.
What makes them a better option than thebarcode and strip technologies that preceded them is that RFID tags can be read up to 300 ft, compared to approximately 15 ft for barcodes. They’re also much faster with read rates of approximately 40 tags/s compared with a half second per read for a barcode reader.
Today’s RFID applications seem endless: baggage tracking, smart passports, animal subdermal tracking tags, credit-card-shaped tags for access, anti-theft merchandise tags in retail operations, warehouse and inventory management , and heavy-duty transponders to track shipping containers, trucks, railroad cars, and heavy machinery. RFID tags also perform well in such harsh environments as oil and gas, chemical, mining, and construction. They track equipment maintenance, are embedded to restrict access to data or devices in consumer electronics, track data-center assets, and provide real-time business intelligence and ROI data. RFID tags are now being combined with sensors so that the tag can work dynamically with the data gathered in real-time by the sensor.
An example of a recently released RFID device is the DLP-RFID2 SMT Module by DLP Design. Residing on a single, compact PCB; t he DLP-RFID2 is a low-cost compact module for reading from and writing to HF RFID transponder tags via an internal or external antenna. All operational power comes from one 3.0 to 5.0-V supply. An external antenna can be connected via a standard u.fl connector or I/O pin/pads.
Featuring a 13.56-MHz reader/writer, RFID/NFC reader, NFC peer and in-card emulation modes, the device reads the UID of up to 15 tags simultaneously. The device has an on-board internal antenna, and FCC/IC modular approvals in place. It has a current consumption reading of 55mA active and 4.4mA idle. The dimensions are 1.65 (L) x 0.735 (W) x 0.27 (H) in..
Applications for the module include real-time security, personal identification, pharmaceutical tracking, inventory/asset management and tracking, library/book management and tracking, baggage tagging, and sports event timing.
The DLP-RFID2-EDK kit is available to assist the developer in creating host software for the DLP-RFID2. The kit includes one RFID2 module, a DLP-RFID2U demonstration platform with an MSP430 microcontroller and LCD module, and a selection of small-format HF antennas.
Fig. 1: DLP-RFID2-EDK: DLP-RFID2U, DLP-RFID2 (shown mounted to the RFID2U) and Antenna Selection. (Source: DLP datasheet.)
An offshoot of RFID, NFC is already included in most smartphones (except the iPhone) where it’s used primarily for mobile payments. By waving an NFC-based smartphone (digital wallet) over or touching it to an NFC-based payment terminal, the phone functions as an ATM. While the digital wallet is so far the most common use, it can also be used to pay for parking at an NFC-based meter, as a transit or boarding pass, or security pass. NFC can also be used for the wirelessly transfer of data between two NFC-resident smartphones. Android’s Beam, BlackBerry, and Windows phones have such sharing features. Google estimates that by next year, NFC-based smartphones will account for 50% of the market.
One of the most compelling uses for NFC technology is in the medical field. Imagine checking into a hospital or clinic or even a doctor’s office with a smartphone, finding instructions on our prescriptions as usage and side-effects info appears on our phone. Medical professionals can use their NFC phones to make sure they are seeing the right patient, for access to areas, and that patients are receiving the prescribed care. Already diagnostic skin tags exist that monitor a patient’s environment, measuring glucose, UV light, or temperature and transmitting the data via a smartphone.
And example of combined NFC and RFID technology is found in the Texas Instruments TRF7970A multi-protocol, fully integrated 13.56-MHz RFID and NFC transceiver IC, an integrated analog front end and data-framing device for 13.56-MHz RFID and NFC systems. Built-in programming options suit it for a wide range of applications such as mobile devices, secure parking (Bluetooth, Wi-Fi, other paired wireless networks, public transportation or event ticketing, a passport or payment point-of-sale (POS) reader, short-range wireless communication tasks such as firmware update, product ID or authentication, medical equipment or consumables, access control, digital door locks, and the sharing of electronic business cards.
Fig. 2: Block Diagram for the Texas Instruments TRF7970A 13.56-MHz RFID and NFC transceiver IC. (Source: Datasheet.)
While both RFID and NFC technologies have existed for quite some time, there has never been the number of applications as there are today. These killer apps, providing secure access and sharing of information at our fingertips, are ensuring that both technologies will be seen in almost every aspect of our lives.
Advertisement
Learn more about Mouser Electronics
