Basics of RFID. What is RFID? How it works? What are target Applications?
First of all, RFID is the abbreviation for Radio Frequency IDentification.
An RFID system serves to identify:
- People (access control)
- Objects (logistics)
- Places (transport systems)
- Transactions (payment systems)
RFID essentially performs the same tasks as the widespread barcode or magnetic strip, but offers several advantages as a successor technology:
- No direct line of sight required
- Read/Write functionality
- Different memory sizes / technologies available
- Security features available
- Multiple tags can be read simultaneously
- Works in harsh environment
How it works?
RFID technology is based on the transfer of data by means of electromagnetic fields – in other words, by radio. Information about an object is stored on a data carrier, known as a transponder or tag, which is attached to the object. This transponder consists of an antenna and a chip containing the individual object data. This information can either be object-related data or simply a unique serial number that creates the connection to the actual data in a database. As with the barcode, the data carrier is attached to the object and allows the information to be read at any time or altered as desired. To do this, the tag communicates with the read/ write station, commonly known as the reader.
What are target Applications for RFID?
- PCB tracking
- Process automation
- Pharmaceutical / medical
- Vending machines
- Service / maintenance
- POS terminals
- Product authentication / brand protection
- Access to buildings / machines
- Immobiliser systems
- Wireless payment / loyalty programmes
An antenna is connected to a transceiver (which is generally known as a reader). Typically, one to four antennas are attached to a single reader, and those antennas send out the reader's signals. Basically, the reader tells the antennas how to generate the proper RF field which can cover area size depending on the power output and the frequency. When an RFID transponder (or tag) moves into the antenna's radio field, it becomes active and sends back to the antenna whatever information has been programmed into its memory. A reader receives the tag's signal through its array of antennas, decodes the signal, and sends the information to the host computer system. A reader can also transmit special signals to a tag — telling a tag to come alive, synchronizing a tag with the reader, or interrogating all or part of the tag's contents.
There are generally two types of transponders: active and passive.
Active transponders have their own power supply in the form of a battery. This enables them to transmit at higher power levels and thus be read or written at greater distances (up to and over 100 m). As a result, these tags are relatively large and, due to the technology, more expensive than passive transponders.
Passive transponders obtain their energy from the electromagnetic field of the reading device. This means that they do not require their own power supply, which makes these transponders very small and economical.Learn More
World International Standardization bodies
There are two main international RFID standards bodies or standardisation bodies:
- ISO - International Standards Organisation
- EPCglobal - Electronics Product Code Global Incorporated
Although these two organisations provide the main RFID standards organisations, there is also a plethora of other standards that apply to niche areas of RFID. In terms of the standardisation organisations ISO is the longest established. In 1996 it set up a joint committee with IEC to look at standardisation for RFID technology. The ISO RFID standards fall into a number of categories according to the aspect of RFID that they are addressing. These include: air interface and associated protocols; data content and the formatting; conformance testing; applications; and various other smaller areas. In addition to the ISO RFID standards, there are also the standards from EPC Global. In 1999 a number of industrial companies with MIT set an consortium known as the Auto-ID consortium with the aim of researching and standardising RFID technology. In 2003 this organisation was split with the majority of the standardisation activities coming under a new entity called EPCglobal. The Auto-ID Center retained its activities associated with the research into RFID technologies.Learn More