RFID Application Introduction
RFID or Radio Frequency Identification is the use of any device that can be sensed or detected wirelessly through the use of radio frequency technology. RFID application has been used in many applications ranging from tagging of library books and assets, electronic toll collection system, healthcare, security access system and many other applications.
A typical RFID system consists of a transponder where a microchip with an antenna is embedded in an item. A reader with antenna is used to read data or write data to the transponder wirelessly. The data read is then passed to a computer where it is used for business transactions.
A study by IDTechEx shows that the market for RFID application in the year 2011 was USD6.51 billion and expected to hit USD7.67 billion in 2012. In the past, the cost of RFID tags was an obstacle to its use in mass quantity. However, as the wireless technology becomes more readily available and cheaper due to its demand in the global market, its use is expected to rise at a rate not imagined before.
There are basically 2 types of RFID in use today. They are passive and active types with frequency ranging from 125kHz to2.45GHz.
The passive tags do not have any transmitter and obtained its power supply from the electromagnetic waves emitted by the reader. This type of tags are cheaper and could range from 15 cents to 50 cents and require minimal maintenance. They have operational range of a few inches to 30 feet. The frequency used can range from 125kHz to 2.45GHz depending on the applications but usually lower frequencies components are cheaper. Passive tags are used in retail business and manufacturing processes.
The active tags have transmitter and its own power source. The power source can be solar energy, batteries or from other sources. The transponder is able to communicate with the reader without getting the power supply from the reader. The range of communication is from 60 feet to 300 feet with higher frequencies used. Frequencies used are 455MHz to 5.8GHz.
The application of active type is in large inventory assets control and containers where they need to be tracked over a larger area or distance. Another application is in electronic toll collection system where the transponder will be active when it received a signal from the reader. It then communicates with the reader and do the necessary transactions after which it will go back to sleep or idle mode. In this way, the lifetime of the batteries used in the transponder is extended.
The RFID passive type where a frequency of 13.56MHz is used in its development can be obtained here.
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