Radio Frequency Identification (RFID) is defined as the use of radio waves to capture and read information that is usually stored on a tag connected to an object. An individual can read a tag up to a number of feet away and it is not necessary for one to be inside the direct line-of-sight in order to track the reader (Ahuja and Pavan 183)
A RFID system comprises of two parts that include a reader, and a label or tag. These tags are fixed with a receiver and transmitter. The two components on the tags of the RFID include the antenna and microchip. An antenna transmits and receives signals. However, information is processed and stored by a microchip. The tag entails the particular serial number for one particular object (Kaur et al 153). To access encoded information on the tag, a two-way transmitter known as a reader or interrogator give out a signal through the antenna to the tag. The responds of the tag depends on the information contained in its memory bank. The read results are then transmitted by the interrogator to the RFD computer program.
History of RFID
RFID was discovered during the Second World War to identifyaeroplanes. The key purpose was to use the radar signal of the airplane to read aproof of identity number to determine if there are enemies or allies.
In 1950s, RFID was explored theoretically with several pioneering scientific and research papers being published. In the 1960s, a number of researchers and inventors initiated prototype systems. Some commercial systems for instance, checkpoint, and sensormatic were connected with the electronic article surveillance (EAS) equipment that was used as an anti-theft system(Kaur et al 153). The 1-bit tags in these systems were used to ascertain the nonexistence or existence of a tag.They were also used in retail stores that sold clothing and other items of high value. This served as the most effective anti-theft measure and was recognized as the prevalent commercial use of RFID. In 1970s, the majority of the research institutions, developers, and researchers had interest in RFID. Most development work was taking place during this period and applications for like animal tagging were very important. RFID applications became popular and many people in difference areas started using them. RFID was very popular and this forced the United States to adopt an electronic toll collection. An electronic tolling system was established in Oklahoma in 1991, resulting in the passage of toll collection points at highway speeds(Ahuja and Pavan 183).Europe further became interested in RFID applications like access control, toll collections, and rail applications.
There was continued development in the 1990s. Presently, there is significant work being done in the rationalization of frequency spectrum allocation between nations, and introduction of various commercial applications. There are more than 350 patents registered with the patent office of the United States associated with RFID and its applications.
The third period of RFID begunin 1998, when researchers started to find and track objects as they moved in the middle oflocations.The research had an international outlook and concentrated on radio frequency technology. It also focused on how information on tags would be scanned and distributed among business partners.The work of the Auto-ID Center centered on decreasing the cost of manufacturing RFID tags, initiating open standards, and utilizing data networks for keeping and delivering large volumes of data.
Categories of RFID Systems
There are three categories of RFID systems as explained below;
Active RFID Systems
In this system, each tag has its specific source of power and transmitted. The battery is the key source of power. Active tags have their own sign to transmit stored data on their microchips. This category of system consistently works in the ultra-high recurrence (UHF) and provides a scope of up to approximately 100m. Active tags are used on expansive items for instance, huge reusable holders, rail autos, and varied resources that should be permitted over long separations. The two important categories of active tags are reference points and transponders. A radio sign from the reader awakens transponders and after power is switched on, it reacts by transferring a signal back. Transponders are used to moderate the life of the battery. Reference points are used as part of the majority of the ongoing finding systems (RTLS) in order to track the added area of an advantage consistently. Unlike the transponders, the reference point sends signals at pre-set interims.
Passive RFID Systems
In passive RFID systems, a radio signal is send to the tag by a reader antenna and reader. This system can operate in varied frequencies for instance, ultra-high frequency (UHF), high frequency, and low frequency radio bands. Because the ranges of a passive system are restricted by the power of the tag’s backscatter, they are usually less than 10m.Since this system does not need a transmitter or source of power and can only require an antenna r a tag chip, they are smaller, less costly, and easier to manufacture as compared to active tags. Passive tags can be packed in varied ways based on the particular application requirements of RFID (Jechlitschek 54). They can be mounted between a paper and an adhesive layer to make good RFID labels. Passive tags can also be mounted in various packages or devices to ensure that the tags are not affected by hash chemicals and high temperatures.Passive RFID solutions are significant in various ways for instance; they are used in supply chain to track goods, and to authenticate commodities like pharmaceuticals. It can also be applicable in distribution centers and warehouses, even though they have shorter ranges, by putting readers at choke points to check on the movement of assets.
Battery-Assisted Passive (BAP) Systems
It is an example of a passive tag that put together an important characteristic of the tag. It uses an integrated source of power commonly battery to power on the chip. The energy apprehendedfrom the reader is used for backscatter. BAP tags lack their personal transmitters (Smart Border Alliance 3).
Components of RFID
A RFID system comprises of three components and they include readers, tags, and host computer system.
It refers to a tiny device in the radio that is known as a smart tag, a transponder, or radio barcode. The tag has a simple silicon microchip that is mounted on a substrate. The entire device can then be encapsulated in varied material like plastic depending on its envisioned use. The concluded tag can be joined to an object like a pallet or box and read to determineits position, state, or identity.
A reader comprises of varied antennas that are accountable for distributing and receiving radio waves. The readers can be either permanent or movable and can read and write information on them. This can be attained in environment where traditional methods of collecting information are not applicable. The main advantage of the reader is that information can be written to the tag several times and consequently, it is easier to store a history with the article.
The picked up data by the readers is transmitted to a host computer that uses specialist software of RFID to transmit information to the correct application for processing into important information (Want 34).
The major difference between frequencies is the rate at which the interrogator produces a field at which tags can operate. A combination of development profiles and physical limitations offer varied benefits and functionality (The Association of the Automatic Identification and Data Capture Industry (AIM) 27).For instance, Hf and UHF tags can only be incorporated at a distance of up to 0.8m and 15m respectively from a reader. HF use silicon chips that are large in size and this result in increased security functionality as compared with the present UHF solutions.
The allocations of frequency are commonly managed through regulations and legislations by the respective governments.Globally, there are variations in frequencies that are used for RFID applications even though standardization through ISO and the same organizations in helping its compatibility.For instance, Europe and the United States use868 MHZ and 915MHZ for UHF respectively. Presently, there are limited frequencies available for RFID applications.
Application of RFID Technology
Presently, most nations have embedded RFID tags for security reasons and personal identification. RFID tags are used in hospital, military, and retail. In hospital, RFID can be used to track the present location of a doctor and inhibit access to sensitive material and drugs. RFID is used in military to track the movement of a person during exercise. RFID tags are further used in retail to offer protection against theft, identify details of a product, and track inventories.
RFID Privacy Concerns
One of the largest barriers to the use of RFID technology is private security concerns. The major fear of clients is tracking their movements after purchasing goods in a store ifRFID tags are used on specific commodities and not removed after purchasing them. Customers are also concerned about having their purchasing habits tracked (Stevanovic 24). EPCglobal initiated a type of switch in tags that enables vendors todeactivate a tag after buying a product. Other initiatives by RSA Security like the development of a Blocker tags has prevented RFID tags from being read.
With regard to frequency, RFID tags are categorized into three:
Low Frequency (lf, 30- 500 KHz)
This type of frequency is less costly compared with the higher frequency tags. Because they are suitable for almost all applications, the required time for a tag to stay in a readers range is high. The main advantage with this type of frequency is that it is least affected by the existence of metal or fluid. One of the disadvantages of this type of frequency is its short reading range.
Ultra High Frequency
This category comprise of tags with the highest range among all tags. It ranges 30 meters and above for active tags and between 3-6 meters for passive tags. UHF has different frequencies in different nations. The high rate of transmission of UHF tags makes it easier to read a tag within a short time. UHF tags are costly unlike other tags and they are highly affected by metal and fluids. UHF tags are mostly used in automated toll collection systems (LIE-ZUDOR et al 56).
This category of tags has high rates of transmission and varies and it is costly as compared with low frequency. The most popular example of HF tags is smart tags and they work at 13.56MHZ.
Benefits of RFID
The detection of a tag without human intervention lessens the cost of employment and reduces human errors that occur during data collection. Secondly, RFID tagshave a longer read range as compared with barcodes. Tags are less sensitive to extreme conditions for instance chemical, physical damage, and dust.
Limitations of RFID
The price of tags varies depending on its type. The cost of semi-passive and active tags is more of interference, permitting their application for scanning goods of high value over long ranges.
An attempt to read a number of tags at time may lead to a signal collision and loss of data. This can only be prevented using anti-collision algorithms, which is an added cost.
The ideal choice of frequency relies on various factors for instance the mode of transmission. RFID tags use two types of data transmission based on the behavior of electromagnetic fields at the chosen frequency.This may have a negative impact on the safe reading range. This is because it is easier to use devices with longer read range in higher frequencies.
In conclusion, RFID technology is significant because it can specifically solve specific problems as explained in this report.
Ahuja, Sanjay, and Pavan Potti.”An Introduction to RFID Technology”.CN, vol 02, no. 03, 2010, pp. 183-186.Scientific Research Publishing, Inc,, doi:10.4236/cn.2010.23026.
Jechlitschek, Christoph. A Survey Paper on Radio Frequency Identification (RFID) Trends.1st ed., 2013,
Kaur, Mandeep et al. “RFID Technology Principles, Advantages, Limitations,& Its Applications”.International Journal of Computer And Electrical Engineering, 2011, pp. 151-157. IACSIT Press, doi:10.7763/ijcee.2011.v3.306.
LIE-ZUDOR, Elisabeth et al. The RFID Technology and Its Current Applications 1st ed., 2006,
Smart Border Alliance,.R F ID Technology Overview. 1st ed.,
Stevanovic, Dusan. Radio Frequency Identification (RFID).1st ed., 2007,
The Association of the Automatic Identification and Data Capture Industry (AIM).Radio Frequency Identification (RFID).1sted., 2001, http://ipmasset.com/docs/RFIDPrimer.pdf.
Want, Roy. An Introduction to RFID Technology.1st ed., 2006,