RFID is in use all around us. If you have ever chipped your pet with an ID tag, used EZ-Pass through a toll booth, or paid for gas using Speed-Pass, you've used RFID. In addition, RFID is increasingly used with biometric technologies for security.Unlike ubiquitous UPC bar-code technology, RFID technology does not require contact or line of sight for communication. RFID data can be read through the human body, clothing and non-metallic materials.
A basic RFID system consists of three components:
1. An antenna or coil
2. A transceiver (with decoder)
3. A transponder (RF tag) electronically programmed with unique information
The antenna emits radio signals to activate the tag and to read and write data to it. Antennas are the conduits between the tag and the transceiver, which controls the system's data acquisition and communication. Antennas are available in a variety of shapes and sizes; they can be built into a door frame to receive tag data from persons or things passing through the door, or mounted on an interstate toll booth to monitor traffic passing by on a freeway. The electromagnetic field produced by an antenna can be constantly present when multiple tags are expected continually. If constant interrogation is not required, the field can be activated by a sensor device.
Often the antenna is packaged with the transceiver and decoder to become a reader which can be configured either as a handheld or a fixed-mount device. The reader emits radio waves in ranges of anywhere from one inch to 100 feet or more, depending upon its power output and the radio frequency used. When an RFID tag passes through the electromagnetic zone, it detects the reader's activation signal. The reader decodes the data encoded in the tag's integrated circuit (silicon chip) and the data is passed to the host computer for processing.
Author: Olga Kharif
Title: "RFID: On Track for a Rapid Rise"
Date: Feburary 4, 2004
page: 1-2
Refrences: http://www.businessweek.com/technology/content/feb2004/tc2004024_8389_tc165.htm?chan=search
20300780 Entry 10
No comments:
Post a Comment