Gurumantras: RFID Q) Sir, these days we hear a lot about RFID. What is RFID? A) Radio Frequency Identification (RFID) is a short term radio - technology that communicates information between a movable and a movable/stationary object. Q) Please throw some light on the History behind RFID. A) The technology behind RFID can be traced back to the nineteenth century where scientists Michael Faraday, James Clark Maxwell, Hertz and Marconi worked on electromagnetic waves (radio waves). Since one form of Radar is the combination of Radio broadcast technology and radar, it is expected that the thoughts of RFID occurred on the heels of the development of radar.[1] During the World War, some crude methods were used to alert the radar crew on the ground about the nationality of the planes.[2] An early work was done by Harry Stockman in his landmark paper, “Communication by Means of Reflected Power” published in 1948. However, it was only in 1950’s that RFID techniques were further explored and gained momentum. RFID tags were first used commercially in 1960s by Sensormatic, Knogo and Checkpoint which developed systems to counter the theft of merchandise. At that time, they could only detect the presence or absence of tags; however the tags could be made inexpensively and hence were quite effective in reducing pilferage. These systems were known as Electronic Article Surveillance (EAS). In the 1970s, notable advances were realized in the field but the intended applications were for animal tracking, vehicle tracking and factory automation. Mario W. Cardullo claims to have received the first U.S. patent for an active RFID tag with rewritable memory on January 23, 1973. Over the years, technology has been developed for multiple uses of tags across different business segments. The latest technology allows a reduction in the size of circuitry, reduction in cost of tags, increased functionality and increased reliability.
Q) Sir, How does this technology work? A) RFID tags are programmed and data is stored in the microchip of the tags. The RFID reader’s antenna transmits electromagnetic waves on the tag’s antenna. The tag sends radio waves back to the reader using power from its internal battery or power harvested from the reader’s electromagnetic field. The receiver picks up these waves and interprets the frequencies as meaningful data.[3] The data transmitted by the tag may provide identification or location information, or specifics about the product tagged, such as price, date of purchase, etc. The radio frequency used determines the speed of communication and the range. Low frequency tags (LF) operate at less than 135 KHz and are appropriate for short range uses like animal identification and anti-theft systems. Devices that operate at 13.56 MHz are known as High Frequency (HF) devices and are primarily used in contactless “Smart Cards”. Frequencies above 900 MHz are known as Ultra High Frequency (UHF) and are used by major retailers in their Supply Chains. Q) How is RFID different from Bar Codes? A) RFID technology doesn’t require direct line of sight whereas Bar Codes require a direct line of sight. RFID tags can be read upto a distance of 300 feets compared to Bar Codes which can be read only upto 15 feets. These two factors in addition to the fact that RFID tags can be read upto the read rate of 40tags/second makes RFID technology quicker to process and less timeconsuming. RFID tags are reusable and the information is alterable due to the read/write nature of the tags. In a RFID tag, Data can be encrypted, password protected, or one can include a “kill” feature to remove data permanently, so information stored is much more secure. RFID require minimal human cost, once the system is set-up compared
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