Radio Frequency IDentification

An RFID is a tiny electronic chip, called an RFID Tag - that can be scanned for information.  It is the same concept that is already in use for automobiles and toll roads, with their "smart tags".  There active RFID tags that do use batteries, and these are used for longer distance scanning and are less common.  But the beauty of this technology is that the most  RFID tags are passive - they do not require a battery !!

An RFID tag is similar to a barcode = but it can hold much more information, and cannot be easily obliterated or covered over like barcodes can.  These tiny tags are also called e-barcodes.  When RFID's are used to identify products in a store - the technology is called EPC (Electronic Product Code).

RFID Scan Frequencies

RFID operates in several frequency bands. The exact frequency is controlled by the Radio Regulatory body in each country.  The most common frequencies for RFID are:

In the UHF band, there are two areas of interest. Several frequencies in the 400 MHz band and then the band 860 930 MHz.  Each of the frequency bands have advantages and disadvantages for operation. The lower frequencies 125-134kHz and 13.56MHz work much better near water or humans than do the higher frequency tags. Comparing passive tags, the lower frequencies usually have less range, and they have a slower data transfer rate. The higher frequency ranges have more regulatory controls and differences from country to country.

The various bodies that control frequencies include the FCC in the USA and CEPT/ETSI in Europe.

The Problem with standard UPC Barcodes - Barcode-based systems are a standard Auto-ID technology, and will be an important legacy system for many years. But all bar codes have a fundamental limitation: they are a line-of-sight technology. This has a number of important consequences. First, in most cases, they need to be scanned manually. This means there is a labor cost associated with every read, and the possibility of human error. It is unlikely that consumers would bother to use bar codes in their everyday lives, scanning bar codes as you put items into the fridge is unlikely to become commonplace, for example. Second, bar codes need to read individually, and therefore singulated. Multiple items cannot be read at one time. Combined, these two factors mean that bar codes are only read at a few control points in the supply chain: in the case of the UPC, for example, normally just once, at the Checkout Counter.

RFID Advantages - RFID tags can contain information such as a product's expiration date and temperature, and they can be scanned from a distance of up to 30 feet. This makes it a lot easier for a retailer to find products in a warehouse and keep track of what condition they're in -- big advantages when it comes to managing inventory.  In fact, RFID tags are already being used to replace the bar codes now used to identify products. Many large retailers, including Wal-Mart, have recently announced their intentions to move over to RFID technology in the near future. RFID allows these companies to track their products using radio-frequency identification tags that can be scanned by radio waves at any time. Recently, there has been a groundswell of RFID-related products and services from IT providers. Microsoft, Intel, IBM and Sun Microsystems have joined vendors such as Texas Instruments, Symbol Technologies, NCR, Accenture and Bearing Point in advocating the technology as the solution for optimizing supply chain operations.