Radio frequency identification (RFID) is a system that transmits the identity (in the form of a unique serial number) of an object wirelessly, using radio waves

RFID or Radio Frequency identification is a technology that enables the tracking or identification of objects using IC based tags with an RF circuit and antenna, and RF readers that "read" and in some case modify the information stored in the IC memory.

The RF tags could be divided in two major groups:

1. Passive, where the power to energize the tag’s circuitry is draw from the reader generated field.
2. Active, in this case the tag has an internal power source, in general a battery that could be replaceable or not, in some case this feature limited the tag lifetime, but for some applications this is not important, or the tag is designed to live more than the typical time needed.

The RF tags could be seen at first sight an "improvement" of the bar codes used today almost everywhere. But they provide several key advantages over the classical optical systems.

Benefits

• Do not require line of sight.
• Could store far more information than a printed bar code.
• In some case are writable, so they could store data during its lifecycle.
• Could have additional electronic that could sense environmental factors as temperature, humidity, light, pressure, etc.
• Provides an automatic way to recognize fuel type for vehicle, issue reward points, collect payment, give reward point or transaction data quickly and easily without human intervention
• Allows data to be transferred securely.
• Companies use independent suppliers, data from each of them can be carried on tags and uploaded to the Company's central system.
• Easy and reference-free identification of customer

Limitations

Every technology has its limitation, and limitation is the key driving force for new technologies to evolve. RFID does have its own limitations.

1. The demand should drive down the price.
2. The smart tag technology is yet to be perfected , today on an average 20% of the tags do not function properly
3. Physical limitations like reading through liquid or metals still exists.
4. Accurate read rates on some items can be very low
5. Nylon conveyor belts and other RFs can disrupt the tag transmissions in warehouses
6. Increase in expenses - the suppliers will have to equip their warehouses and transport vehicles with readers. These readers have to be connected to the computer networks for exchange of information. All these mean additional costs related to hiring technical consultants and additional hardware.

Concerns

Some key concerns associated with RFID technology that restricts its operational viability includes:

1. The basic privacy concerns associated with an RFID system is the ability of ubiquitous tracking of anybody without consent.
2. With RFID tags getting smaller and smaller, it is now even possible to hide tags in such a way that the consumer may be unaware of the presence of tags.

New Security Features

However, as technology is evolving, it’s getting richer with features to address existing concerns.

Some of the new security features added to the technology includes:

1. Spamming any reader that attempts to scan tags without the right authorization, thus confusing the reader to believe that there are many tags in its proximity.
2. Kill Switches: Newer RFID tags are being shipped with a Kill Switch, which allows the RFID tags to be disabled.

Technology and Architecture

RF (Radio Frequency) communication occurs by the transference of data over electromagnetic waves. By generating a specific electromagnetic wave at the source, its effect can be noticed at the receiver far from the source, which then identifies it and thus the information.

The RFID tag which contains the tagged data of the object generates a signal containing the respective information which is read by the RFID reader, which then may pass this information to a processor for processing the obtained information for that particular application.

An RFID tag is composed of an antenna, a wireless transducer and an encapsulating material.

These tags can be either active or passive. While the active tags have on-chip power, passive tags use the power induced by the magnetic field of the RFID reader.

An RFID reader consists of an antenna, transceiver and decoder, which sends periodic signals to inquire about any tag in vicinity. On receiving any signal from a tag it passes on that information to the data processor.

The data processing subsystem provides the means of processing and storing the data. RFID systems can also be differentiated based on the frequency range it uses.

• 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-frequency (850 MHz to 950 MHz and 2.4 GHz to 2.5 GHz) systems, offering long read ranges (greater than 90 feet) and high reading speeds, are used for such applications as railroad car tracking and automated toll collection.

However, the higher performance of high-frequency RFID systems incurs higher system costs.

Industry Standards

RF (Radio Frequency) communication occurs by the transference of data over electromagnetic waves. By generating a specific electromagnetic wave at the source, its effect can be noticed at the receiver far from the source, which then identifies it and thus the information.

Standards are critical in RFID. Be it payment systems or tracking goods in open supply chains. A great deal of work has been going on to develop standards for different RFID frequencies and applications.

RFID standards deal with the following:-

• Air Interface Protocol - The way tags and readers communicate
• Data Content - Organizing of data
• Conformance - Tests that products meet the standard
• Applications - How applications are used

There are two major and somewhat conflicting organizations into the standards business

• ISO
• Auto-ID Centre (now handled by EPC Global).

EPC standards for tags are the class 0 and class 1 tags:

• Class 1: a simple, passive, read-only backscatter tag with one-time, field-programmable non-volatile memory.
• Class 0: read-only tag that was programmed at the time the microchip was made

Class 1 and Class 0 have a couple of shortcomings, in addition to the fact that they are not interoperable. They are incompatible with ISO standards. The new EPC standard ~V Gen2 is designed to be fast tracked with ISO standards but for some disagreements over the 8 bit Application Family Identifier (AFI).

ISO has developed RFID standards for automatic identification and item management. This standard, known as the ISO 18000 series, covers the air interface protocol for systems likely to be used to track goods in the supply chain. They cover the major frequencies used in RFID systems around the world.

Applications

There are two main area of applications, defined broadly as proximity (short range) and vicinity (long range).

Some other areas where passive RFID has been applied in recent past are:

• Person Identification
• Food Production Control
• Vehicle Parking Monitoring
• Toxic Waste Monitoring
• Valuable Objects Insurance Identification
• Asset Management
• Access Control
• Mass Transit Ticketing

Some areas where Active RFID has been applied in recent past are:

• Inventory Control
• Asset Tracking