Abstract’RFID (Radio Frequency Identification) uses radio wave to identify an object. It’s mainly used to automatic identification of object in similar manner to barcode but it is not replacement of barcode. Different varieties of RFID tags can be found in market based on their functionalities.
Index Terms – History of RFID, Classification of RFID tags, RFID application, RFID frequency band, RFID privacy concern
RFID contains silicon chip and antenna. RFID tags can be attached to any object. RFID tags antenna’s main task is to process of energy capture and transfer of unique tag id. A tags chip can contain data related to any product like manufacture name, model no etc .It can also stores more information as compare to barcode. It has been widely used in application like tracking system like inventory tracking system. Also used in automatically identify object in similar manner to barcode but It carries additional advantage over barcode that’s, it doesn’t required straight line to read the tag. Although RFID reader has longer read range as compare to barcode. It can be also used to identifying objects concurrently. E.g. Prof can take attendance of the entire class at a time instead of taking attendance one by one. Following figure shows basic working of RFID technology.
RFID was invented by the BRITISH in World War 2 to identify airplane remotely that is whether plane as friend or enemy.
The first commercial application of RFID is ‘EPC'( Electronic Article Surveillance). It was developed in 1970s as theft prevention system. That was based on tags that can store a bit. That bit was read when customer lefts stores and system would ring alarm if bit was not unset.
In the end seventies RFID was used for animal tagging.
In the 1980s, US state decided to use RFID as toll collection.
The first paper related to RFID is released by Harry stockman.
The first patent on RFID was issued in 1973 for a passive radio transponder with memory
III. CLASSIFICATION OF RFID
RFID tags can be classified in two categories.
W1) Active tags 2) Passive tags and 3) Semi passive tags.
1) Active tags contains internal power source. It can transmit stronger signal. It has longer read range up to 100 meters. Its main drawback is that is dependent on battery life. It is costly as compare to passive RFID tags. Its size is relatively same as deck of playing card. The lifetime of Active tag is up to 5 years.
2) Passive tag gets power from external reader. Since the lack of a battery, passive tags are the smallest and cheapest tags available It transmits weaker signal. Its size is smaller and it is also cheaper as compare to Active tags. Because of above advantage passive tags are used most commonly in market. It can be read tags up to few meters (10 cm to few meters). It is long lasting because it do not contains internal power source.
3) Semi passive tags are those tags that have an internal power source that keeps the micro chip powered at all times. Because of this advantage chip can respond faster to queries as compare to passive tags. It is also costly as compare to passive RFID tag. As well as in semi passive RFID tags the antenna is not required for collecting power that is why it can be optimally used for back scattering and therefore increasing the reading range. Because the tag does not use any energy from the field the back scattered signal is much stronger and increasing the range even further. Therefore, a semi-active tag has usually a range larger than a passive tag. RFID tags can also classify in read only tags and read/write tags
IV. APPLICATION OF RFID
1) RFID tags can be used in supply chain management that is shown in below figure.
2) Nowadays, many countries embedded RFID tags in passport for personal identification and security reason.
3) RFID tags can be also used electronic payment system like debit card and debit card.
3) RFID is currently used in military, hospital, retail etc. In hospital RFID can be used in tracking of equipment, tracking the current location of doctor and restrict access to drug and other sensitive material.
4) In military, RFID can track personnel movement during exercise. It can also be used in identify vehicle as being either military or non military.
5) In retail, RFID can be used to provide protection against theft, tracking of inventories, identify product details.
V. FREQUENCY RANGE
RFID tags can be further classified into three regions in respect to frequency:d
1) Low frequency (LF, 30 – 500 kHz)
This type of tags is cheaper than any of the higher frequency tags. Because they are enough fast for almost all the applications, however for larger amounts of data , the time required for a tag has to stay in a readers range will increase. Advantage of LF tag is that low they are least affected by the presence of fluids or metal. The disadvantage of such tags is their short reading range
2) High frequency (HF, 10 – 15MHz)
This types of tags have higher transmission rates and ranges but also more expensive than LF tags. Smart tags are the most common example of HF tags and they work at 13.56MHz
3) Ultra high frequency (UHF,850 – 950MHz, 2.4 – 2.5GHz, 5.8GHz)
This type of tags has the highest range of frequency among all tags. It ranges from 3-6 meters for passive tags and 30+ meters for active tags. Frequency range for UHF tags is differ for different countries. UHF tags have the higher transmission rate, which allows reading a tag in a very short time. This feature is important where tagged items are moving with a high speed and remain only for a short time in a readers range. UHF tags are also more expensive than any other tag and they are severely affected by fluids and metal. UHF tags are mostly useful in automated toll collection systems
VI. RFID PRIVACY CONCERN
Personal security concerns can be one of the largest barriers to widespread adoption of RFID technology. Customer fears that their movements could be tracked after leaving a store if RFID tags are used on particular products and not removed when it is purchased. Consumers have also voiced concern over having their buying habits automatically tracked. EPCglobal has designed a type of switch in tags that will allow vendors to permanently disable a tag at point of sale. RSA Security has also developed a ‘Blocker Tag’ which can be used as a shield to prevent RFID tags from being read.
We can conclude that with the help of RFID technology we can efficiently solve particular problems as discussed in report in faster way.
 Radio Frequency Identification. Wikipedia.
 A survey paper on RFID trends by Christoph Jechlitschek
 RFID (Radio Frequency Identification): Principles and Applications by Stephen A. Weis MIT CSAIL
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