RFID: Radio Frequency Identification

RFID, short for Radio Frequency IDentification, a technology similar in theory to bar code identification. RFID systems can be used just about anywhere, from clothing tags to missiles to passports to driver licenses -- anywhere that a unique identification system is needed. The RFID market is the fastest growing sector of the radio technology industry, with around 900 million $US in sales in 2005.

How it Works

A RFID system is made up of two components the Transponder and the Interrogator /reader. A reader typically contains a transmitter and receiver, a control unit and a coupling element. Many readers can also pass information on to other systems such as a PC. The transponder which is where data is stored consists of a coupling element and an electronic element. The transponder does not have its own power supply. When not in the interrogation zone of a reader it is totally passive. The power needed to run the transponder is supplied from the readers coupling unit.


Types of RFID Tags

Passive Tags

One type of RFID tags are known as 'passive tags'. Such tags do not use batteries and have no other internal power supply. Instead they utilize the electrical current from incoming radio signals to transmit a response. Such tags can not only broadcasting identification codes, but can also store small amounts of data, such as time and dates, which can monitor and report on the freshness of a product.

Semi-Passive Tags

Some radio frequency identification tags include a small built-in battery used solely for the purpose of storing data within the chip. Known as ‘semi-passive’ RFID tags, these tags allow for increased data storage, faster response times and increased transmitting distance. However they also have the additional capability of using the electrical current from incoming signals to power their reply.

Active Tags

‘Active’ tags use a larger internal power source to store both data and emit signals. These tags, also known as ‘beacons’, yield much larger transmission distances and have the ability to store and transmit data for a period exceeding ten years. Their disadvantage is they are considerably more expensive and larger than their ‘passive’ counterparts, on average the size of a coin. These tags might be utilized for larger shipments such as the crates that the products are shipped in.

Use of RFID tags

Today, RFID tags are employed in several ways. This list is growing as companies, businesses, and government institutions find new ways to use RFID tags:
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- Highway transponders for tolled roads (i.e. the ETR in Ontario)
- Global Positioning Systems (GPS)
- Pallet tracking in warehouses making barcodes obsolete
- Pet tracking and owner identification
- Anti-theft tracking in retail stores
- Use in keycards/ID cards for secure access, replacing magnetic strips or barcodes (Press Enterprise, 2006)
- Use in paper money to determine counterfeits

Advantages of RFID

There are several benefits to RFID tags that make them marketable to governments and corporations. For example, passports that are equipped with the tags will allow travellers to move through airport security without stopping to have their passport checked by customs officials. Hence, users of RFID are open to convenience.

Businesses and corporations also benefit from RFID. In management of supply chains, RFID tags allow suppliers to view location, movement and consumer demand for certain products (IBM, 2006) (IBM's "helpdesk", for example, provides RFID tracking solutions). This is opposed to having to physically count inventory and scan barcodes, which can present a logistical problem when products come in large quantities. RFID also makes business more secure (as in the Wal-Mart's case), since inventory can be tracked. This would result in lesser thefts occurring.

When applied to the consumers, businesses are able to create an interactive shopping experience for consumers, since their preferences and activity can be tracked through the use of RFID tags. Additionally, easier payment options can be made available if RFID tags are integrated with a pre-paid system, where a set amount is embedded into the tag. At the moment, RFID tags are moving forward into their second generation, but as they evolve, more options for their use will come about.

Disadvantages of RFID

The issues that revolve around the use of RFID tags consist largely of issues with privacy of users who are unaware that they are being tracked with an RFID tag. In many cases, consumers do not know that the product they are purchasing is equipped with an RFID tag.

Privacy advocates have raised the concern that the use of RFID can be scanned remotely, leading to a breach in the privacy of the individual (Richardson, 2006). A panoptic surveillance could be the possible result, where individuals will no longer be able to tell if they are under surveillance.

Another major concern is identity theft. RFID tags can be read by anyone that carries an RFID reader that is tuned to the proper frequency. As a result, criminals may have access to sensitive information that is made available through RFID tags. For example, the implementation of RFID tags into devices like credit cards, driver's licenses, passports, or keycards can be stolen.

Since RFID tags contain unique information, consumers may be keen to such technology since it affords them the convenience of having their preferences predicted when they are shopping or searching for products. This convenience can quickly turn into a problem when the tags carry anything from information about pant sizes, reading preferences, and a history of purchases, to information about medications, personal addresses or phone numbers, and banking information (Stockstill, 2006).

To view a video clip containing some of the disadvantages of RFID click here.

Case Studies

The 407 ETR

As the declining price of RFID tags make RFID systems economically viable, we are beginning to see this technology being put into use. The use of this technology in Canada is widespread, and is proving to be especially useful on roadways. As an example, 407 ETR Corporation, the company behind the new toll highway in Toronto's north end, uses RFID technology to replace the need for toll booth workers. Opened on October 14, 1997, the 407 ETR is a 108 kilometers transportation route serving daily commuters, varied industries and geographical markets. The electronic RFID receivers located on each overhead gantry capture driver information from RFID enabled transponders when passing through on-ramp and off-ramp portals. The use of such technology allows the ETR Toll-way to streamline billing by capturing the location, time and date of entry and exit.

Source: Welcome to 407 ETR [online]


FedEx makes use of RFID as well, to view the case study on FedEx click here.

Human Implantation of RFIDs

Human implantation of a radio frequency identification ship is now possible with modern technology and medicine.

RFID chips are most commonly implanted into the webbing between fingers or forearm and allow the owner, carrying the implant, such features as the ability to automatically open and unlock doors. It may even grant access to ones own computer.

The chip is enclosed in a glass casing which is inserted into a medical syringe and injected directly into the patient, with the only medical risk being infection. Such an operation could be performed by a physician or plastic surgeon using local anaesthetic.

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Such an RFID can be purchased on sites such as www.phidgetsusa.com where they sell RFID tags 3mm in diameter and 13mm long, for little more than two American dollars. Readers for such tags are also available from Phidgets.

As this technology is still new, most software for chips and readers must be engineered privately, with little for sale.

FDA and the VeriChip

In 2004 the Food and Drug Administration (FDA) decided that Applied Digital Solutions could market their RFID chip, the VeriChip, for implantation with intent of serving medical purposes.

The VeriChip, if used in health applications, would be scanned by doctors or other medical personnel and in turn produce a numeric code. This numeric code is linked to the patients file, producing faster access you vital information.


Amal Graafstra

Amal has an RFID tag implanted in his hand, learn more here.


"RFID: Technology tracks goods, now people." The Press-Enterprise (Riverside, California) (via Knight-Ridder/Tribune Business News) 20 Jan. 2006. Infotrac OneFile. University of Toronto Libraries. Brampton. 21 Feb. 2006.

Mason, Stockstill. "New library tracking system raises concerns." Inland Valley Daily Bulletin (Ontario, California) (via Knight-Ridder/Tribune Business News) 24 Jan. 2006. Infotrac OneFile. University of Toronto Libraries. Brampton. 21 Feb. 2006.

Richardson, W. Tim G. "RFID - Radio Frequency Identification." 12 Jan. 2006. Seneca College/University of Toronto. 21 Feb. 2006 <http://www.witiger.com/ecommerce/RFID.htm>.

IBM Canada. "Strengthening the Supply Chain." IBM Canada. 21 Feb. 2006 <http://www-306.ibm.com/e-business/ondemand/us/adv/ca/supply_chain.shtml>.

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