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RFID enabled Document and Asset tracking solutions
 
 
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RFID Systems…
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RFID technology can be applied to many business processes, namely asset management and tracking, logistics, product identification and tracking, personnel tracking, access control, document management and so on. This technology is also used in quality control processes, product authentication and even operational productivity.

Low-frequency (30 KHz to 500 KHz) systems have short reading ranges and lower system costs. They are most commonly used in security access, asset tracking, and animal identification applications. High (HF)and Ultra High Frequency (UHF) (850 MHz to 950 MHz and 2.4 GHz to 2.5 GHz respectively) systems, offering long read ranges (greater than 30 metres) and high reading speeds, are used for such applications as railroad car tracking and automated toll collection.

The significant advantage of all types of RFID systems is the non-contact, non-line-of-sight nature of the technology. Tags can be read through a variety of substances such as snow, fog, ice, paint, crusted grime, and other visually and environmentally challenging conditions, where barcodes or other optically read technologies would be useless.

RFID tags can also be read in challenging circumstances at remarkable speeds, in most cases responding in less than 100 milliseconds. The read/write capability of an active RFID system is also a significant advantage in interactive applications such as work-in-process or maintenance tracking. Though it is a costlier technology (compared with barcode), RFID has become indispensable for a wide range of automated data collection and identification applications that otherwise, would not be possible.

An RFID system consists of three components: a tag, a reader, and a database.

Types of tags

RFID tags are produced in various configurations depending on their functionality. Following is a list of the functionality associated with each class of tag.
Class Attributes
Class 0 Read only passive ID tags
Class I Write once passive ID tags
Class II Passive tags with added functionality, eg memory or encryption
Class III Semi – passive
Class IV Active tags – communicate with readers and other tags on the same frequency band.
Class V Essentially readers can power class I,II, and III as well as communicating with Class IV and with each other
A tag consists of a microchip, and an antenna imbedded in a substrate (usually paper or plastic). Every tag is uniquely identified and is either passive, semi passive or active.

Passive Tags

Passive tags are composed of an integrated electronic microchip and an antenna coil that includes basic modulation circuitry and a non-volatile memory.

The tag is energized by a time-varying electromagnetic radio frequency waves that are transmitted by the reader. The information contained on the tag is transmitted back to the reader through the same radio waves.

The unique identity of the tag is decoded by the reader and passed to a host. Tag manufacture can be customised to suit to the application for which its intended.

Anatomy of a passive label
Active Tags

Active tags are powered by an internal battery and are typically read/write, i.e., tag data can be rewritten and/or modified. An active tag’s memory size varies according to application requirements; some systems operate with up to 1MB of memory. In a typical read/write RFID work-in-process system, a tag might give a machine a set of instructions, and the machine would then report its performance to the tag.

This encoded data would then become part of the tagged part’s history. The battery-supplied power of an active tag generally gives it a longer read range. The trade off is greater size, greater cost, and a limited operational life (which may yield a maximum of 10 years, depending upon operating temperatures and battery type).

Readers

Readers are the communication core of RFID systems they can both read and write to compatible tags.

Readers come in many different configurations and can be hand held or fixed depending on the required function. Most of them have the following integrated components: Antenna, Transceiver, Microprocessor, Memory, Communications Interface, Power source and Controller.

Radio Frequency Ranges

RFID systems are also distinguished by their frequency ranges as detailed in the following table.
Band Frequency Range Frequency Used Tag type Read Range Application
Low(LF) 30  – 300 KHz 125 or 134 Khz Passive 15 - 90 cm Animal ID, Security Personnel Tracking
High (HF) 3 – 30 Mhz 13.56 Mhz Passive 15cm – 1.2 m Item tracking Document Tracking
Ultra High (UHF) 300 Mhz – 1 GHz  866 - 950 MHz Active and Passive 3 to 6 m Product tracking, Logistics
Micro Wave (MW) 1GHz up 2.5 or 5.8 Ghz Passive and Semi Passive 30 m Railroad container tracking, Tolls, E-tag
                            
Last updated date:15/06/2010  web site by