Network management Toolkit

RFID: An idea whose time has come

Mark Kaelin Builder.com

Published: 19 Feb 2004 15:29 GMT

In the information age, technical innovation is expected. We're frequently bombarded with the newest, latest, greatest technological innovations known to humankind only to be disappointed in what turns out to be merely the flash in the pan of marketing hype.

Radiofrequency identification (RFID), on the other hand, seems to have matured beyond the hype into the realm of practical products and useful services. To be sure, RFID has seen its share of hyperbole and hype -- refrigerators that order milk for you and Tupperware that tells you the sauerkraut is no longer edible come to mind. But putting these spectacular and peculiar applications aside for the Hammacher Schlemmer crowd, there is a real, growing market for the services and products RFID systems can offer.

As the need for RFID products increases, the opportunities for developers to write code that takes advantage of the unique qualities of this technology will be plentiful. In preparation for the inevitable increased need for qualified programmers and designers, let's take a look at what RFID is and what products are currently in use.

Get a technical description of what happens
A basic RFID system consists of three components:

An antenna

A transceiver, which includes a decoder

A transponder, in the form of an RF tag, electronically programmed with unique identifying information

When the antenna is packaged with the transceiver and decoder it is called a reader or interrogator. The RFID tags come in a variety of sizes and shapes, ranging from millimetres to credit-card sized.

RFID tags can be passive or active. An active tag is powered by an internal battery, while the passive tag gets its power from the reader that is attempting to access it. The key advantage of RFID products is the non-contact, non-line-of-sight aspect of the technology. The only limitation is the range of the emissions, which is determined by the power supplied to the system and the operating frequency of the tag.