The RFID system comprises an antenna, transceiver, that marks the radio frequency and transmits the data to a processing device, and a tag or transponder, which is an integrated circuit comprising the RF circuitry and data to be transmitted.
In this system, signals are transmitted by electromagnetic or electrostatic coupling in the radio frequency section of the electromagnetic spectrum. The technology works in a similar fashion as barcode identification. One of the fundamental difference between them is that RFID eradicates the necessity for line-of-sight reading that the barcoding depends on.
Along with this, RFID scanning can be performed at longer distances than barcode scanning, as these systems have multiple frequency bands ranging from 120-150 KHz(LF) to13.56 KHz(HF) to 865-930 MHz(UHF) to 2.4-5.8 GHz(Microwave), which offer a transmitting range from 10 cm up to 200 m.
There are three types of tags: Active, Passive and Battery Assisted Passive(BAP). Active tags contain a battery and transfer signals autonomously, whereas passive contains no battery and requires an external source to evoke signal transmission. BAP uses battery for internal operations, but, at the same time requires reader for power to transmit the signal.
Participants have to wear a chest number containing passive tags that are read by antennae placed alongside the track. Ultra high frequency (UHF) tags are used, which give correct readings with specially designed antennae.
This method has been adapted by many recruitment agencies, like the Indian Railway Recruitment Cells, the police, and the power sector, where the candidates have to clear a PET (Physical Endurance Test) in their qualifying procedure.
RFID in Asset Management
RFID, along with moblie computing and web technologies, give an efficient way for companies or organizations to handle and record their assets along with their current status. Mobile computers, with integrated RFID readers, provide a complete set of tools that eliminate paperwork, and provide confirmed proof of identification and attendance.
RFID in Logistics and Transportation
RFID technology plays a key role in the field of logistics and transportation. Due to its business value and efficiency, transportation companies are implementing this technology in increasing numbers.
For example, the North American railroad industry has implemented RFID in its automatic equipment identification system. In this system, locomotives and rolling stocks are fitted with two passive tags that identifies the car number, type of equipment, equipment owner, number of axles, etc.
Aerospace applications have also incorporated the technology by tagging baggage with RFID tags, which are read by the airport's baggage-handling system. This helps improve the efficiency and reduces the possibility of misplaced items.
These were just a few of the many applications of radio frequency identification technology. These systems can be used wherever a unique identification system is required, from clothing tags to missiles to pet tags and food.