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1.What is RFID?
2.History of RFID
3.RFID Theory
4.Types of RFID Tags
5.What is RFID Reader?
6.Classification of RFID Frequency
7.RFID Applications
8.Benefits and Characteristics of RFID
9.Problems with RFID
10.Future of RFID
11.Successful Examples of RFID
12.RFID Relative Links
13.RFID Glossary
What is RFID?
Radio Frequency Identification (RFID), one member in the family of Automatic Identification and Data Capture (AIDC) technologies, used to describe a system that transmits the identity of an object or people wirelessly without physical contact by radio waves.

There are two components to any RFID system: a transponder called a “Tag”, and an interrogator called a “Reader”. Tags are the antenna enables the chip to transmit the identification information to a reader. With this in mind, each tag carries a unique identification number; which is programmed at the time of manufacturing to ensure the object can carries a distinctive identity and description. Readers are a component to scan the tags for their data, and a series of integration technologies that link the readers back to central systems that track the data being scanned.

History of RFID
RFID technology was invented in 1945, but it was not mainstreamed for commercial applications until the 1980s.

The first similar RFID tag invention was invented in 1945 by Leon Theremin, which the Soviet Union used as an espionage tool, not a RFID tag or chip, but it is accredited to being the technology that was used to develop the current RFID tags or chips.

More relevant technology was during Second World War, called IFF (Identification Friend or Foe), which used by the British in the World War II for the detection of airplanes of both friends and enemies.

In 1973, Mario Cardullo holds the patent for a passive radio transponder with memory- the modern RFID that uses radio waves to collect information from the memory.

In 1987, the first RFID road toll collection implemented in Norway.

Soon this technology began to invade everything. Nowadays, RFID is used in many applications: identification of all sorts of products, banking (VISA card…), security (E-seal and RFID system for custom, Boiler and equipment monitoring system, fireworks management, logistics management, security system for sections…), personnel identification, medical identification and wine identification.

1940 - 1950 Radars developed for the purpose of WWII
First similar RFID tag invention in 1948
1950 - 1960 Early explorations of RFID technology
1960 - 1970 Start of applications field trials
1970 - 1980 RFID really beginning to get popularized
1980 - 1990 Commercial applications of RFID enter mainstream market
1990 + RFID becomes a part of everyday life
RFID Theory
The RFID system typically consists of a tag made up of a microchip with an antenna, and an interrogator (reader), which is embedded with a single chip processor and an antenna.

The purpose of an RFID system is to enable data to be transmitted by a tag, which is read by an RFID reader and processed according to the needs of an application. Moreover, the data transmitted by the tag may provide identification or location information, or specifics about the product, for example, price, color, date code, etc. Also, RFID systems can be employed for tracking objects- as an invasion of privacy.

In short, RFID tags can carry data and serve as data transfer agents; a reader in range of the tag’s signal will receive the data, decrypt it, and forward it to the host computer for stores all collected data within a database.

The process of RFID system ( by Frequency Ware Inc.)
Types of RFID Tags
Generally, there are two types of RFID tag: active and passive.
  • Active RFID Tags
Active RFID tags contain an internal power source (battery) to transmit signal to reader. Active tags have greater communication distance and larger memory capacity then Passive RFID tags.

According to own power source, active RFID tags of a range of up to 1,500 feet and have a battery life of up to 10 years. The advantages of active tags are reliability, precision, and superior performance in adverse environments, like metallic and so on.

  • Passive RFID Tags
Passive RFID tags have no internal power supply. These passive tags are powered by an incoming radio frequency, which is received through the tag’s internal antenna. So, passive tags are read at a relatively short range from a distance of ten millimeters to over six meters away.

At present, these tags are enough to relay simple information, like number or name. The size of passive tags is small and thin. And, it is the lowest price of RFID tag.

Active RFID Tags
Passive RFID Tags
Battery powered Powered by radio frequency
Read-write and read only versions available Read-write and read only versions available
Longer read ranges (10 to 1,500 feet) Shorter read ranges (Inches to 22 feet)
Higher tag costs ($10 to $1000 per tag) Lower tag costs (Less than $1 per tag)
2D location systems possible Item ID
Active Tags will broadcast all the time or sit waiting for a request from a reader to blast its signal. Item management
  •  Semi-passive RFID Tags
Semi-passive RFID tags are similar to Active RFID tags- battery powered, yet, it only uses for internal power from RF energy from the reader to broadcast the reply’s signal to reader. And, the battery doesn’t power as much as the active tag internal power source does. On the other hand, the semi-passive RFID tag can perform functions that a passive RFID tag cannot perform.
What is RFID Reader?
Basic function of the RFID reader is to converse with the RFID tag by originating radio waves from its antenna.

The RFID readers are classified on their variety, such as Microwave frequency, UHF (Ultra-high frequency), HF (High frequency) and LF (Low frequency) that are 5.8 GHz to 125 KHz. There costs are also reliant on their range; Microwave frequency readers are costliest, LF readers are the cheapest.

Mainly, there are two types of RFID reader: handhold and fixed.

  • Handhold Type Reader
The Handheld reader fits comfortably in the palm of your hand. Users carry this portable Reader while looking for specific items such as merchandise, inventory, or other assets.

The Handheld reader not only can be used to manually scan but also program individual tags. Instead of reading all tags in an area at one time, users can selectively read and program only particular items.

  • Fixed Type Reader
The fixed reader is an RFID interrogator mounted to a permanent or non-mobile structure enabling users to read RFID tag numbers attached to movable items.

Classification of RFID Frequency
Different frequencies have different characteristics that make them more effective for different applications.
There are four commonly used frequencies:
  • Low frequency
This Low frequency (LF) RFID operates at less in 125 to 134.2 KHz frequency, as well its read range is limited to less than a foot (0.33 meter). This frequency is typically used for short range RFID applications, for example, Access control. Besides, the LF tags use less power too.
  • High frequency
This High frequency (HF) RFID operates at round 1-400 MHz. The common specification is 13.56 MHz frequency, and its read range is longer than LF, generally 6-12 inches (medium read range). This kind of HF RFID tags are best suited for applications and often used in manufacturing processes and tracking and so on. For instance, library book tracking, Smart Cards.
  • Ultra-high frequency
This Ultra-high frequency (UHF) RFID operates at round 860 MHz to 960 MHz frequency and can read at long distances, up to 15 feet. This UHF RFID tags are mainly used for tracking cases and pallets. They can offer better range and can transfer information faster and farther than LF and HF RFID tags. But radio wave cannot pass through metallic and liquid items.
  • Microwave frequency
This Microwave frequency RFID operates at round between 1 to 5.8 GHz, and can used for long distance. The electronic toll collection is an example of this tag.

List of RFID Frequency




902-928 MHz


920-926 MHz


865.6-867.6 MHz


865.6-867.6 MHz


902-907.5 MHz



902-928 MHz


917-922 MHz

Costa Rica

902-928 MHz

Czech Republic

865.6-867.6 MHz


865.6-867.6 MHz

Dominican Republic

902-928 MHz


865.6-867.6 MHz


865.6-867.6 MHz


865.6-867.6 MHz


865.6-867.6 MHz

Hong Kong, China

920-925 MHz

865-868 MHz


865.6-867.6 MHz


865.6-867.6 MHz




865.6-867.6 MHz


952-954 MHz

Korea Republic

908.5-910 MHz

910-914 MHz


865.6-867.6 MHz


866-869 MHz

919-923 MHz


865.6-867.6 MHz


902-928 MHz


865.6-867.6 MHz

New Zealand

864-868 MHz


865.6-867.6 MHz


918-920 MHz


865.6-867.6 MHz


865.6-867.6 MHz


865.6-867.6 MHz

Russian Federation

865.6-867.6 MHz


866-869 MHz

923-925 MHz


865.6-867.6 MHz

South Africa

869.4869.65 MHz

917-921 MHz


865.6-867.6 MHz


865.6-867.6 MHz


865.6-867.6 MHz


922-928 MHz


920-925 MHz


865.5-867.6 MHz

United Kingdom

865.6-867.6 MHz

United States

902-928 MHz

RFID Applications
RFID has applications in various industries. RFID applications help in tracking products in the supply chain and during the manufacturing process. Different kinds of frequency RFID tags have different applications. Such as, LF (Low frequency) RFID tags are model for scanning objects at close range. UHF (Ultra-high frequency) RFID tags are best for scanning boxes of goods, and so on.

Some applications can be summarized as follows.

  • Supply chain automation
  • Warehouse control system
  • Retail control system
  • Manufacturing
  • Industrial automation
  • Custom management
  • Asset management
  • Security systems
  • Medical applications
  • People tracking
  • Location control
  • Logistics management
  • Passenger and transportation management
  • Animal Identification
  • Container control (E-seal…)
  • Harbor container management system
  • Boiler and equipment monitoring system
  • Automatic monitoring management system
  • Timing
The above list is only small representation of RFID applications in the RFID market. RFID applications are still being developed and improved as the technology advances.

Moreover, the RFID technology is advancing day-by-day and researches are on to help reduce the cost that can lead to easy availability of the RFID services. Thousands of worldwide companies have renovated to RFID systems to improve efficiency in production and security features.

Benefits and Characteristics of RFID
Nowadays, RFID is already having a significant impact on many businesses.

RFID can deliver benefits in many areas from tracking work in progress to speeding up throughput in a warehouse and so on.

Here is the list of RFID benefits and features.

  • RFID (Tag) can be read from a distance and from any orientation
  • RFID(Tag) do not require line of sight to read
  • RFID (Tag) have both read and write capabilities
  • RFID (Tag) Can provide large amounts of data
  • RFID (Tag) can be embedded easily into different objects
  • RFID (Tag) can read at rapid rates- at a speed of up to 1,000 tags per second
  • RFID (Tag) can be read in harsh environments where operating temperatures range from 22 degree Fahrenheit to +159 degree Fahrenheit
  • RFID (Tag) is costly but efficient
  • RFID (Tag) do not get damaged easily
  • RFID system offers permanent identification- tags encrypt information with unique identification
  • RFID reduces administrative error, labor costs associated with scanning, reading and shipping
  • RFID improves businesses and guarantee traceability
  • RFID can help to improve the forecasting
Problems with RFID
RFID technology has a lot of benefits, but it also has several drawbacks that have limited its adoption on a more widespread scale.
There are some problems with RFID:
  • About privacy problem, RFID tags can be read without your knowledge and agreement:
    Because of the tags can be read without obviously scanned, anyone with an RFID tag reader can read the tags embedded in your belongings without your agreement.
  • About security problem, RFID tags are difficult to for consumers to remove: some are tiny; others may be embedded inside a product where consumers cannot notice it
  • About standard problem, RFID has been manufactured in different ways by different manufacturers: this issue may be cause problems for companies
  • About interference problem, RFID systems can be easily disrupted: the electromagnetic spectrum is easy to jam at the right frequency, and active RFID tags can be repeatedly disrupted to wear the battery down
  • About reader collision problem, RFID reader collision occurs when the signals from two or more readers overlap: the tag is unable to respond to simultaneous queries
  • About tag collision problem, RFID tag collision occurs when many tags in a small area meanwhile: it is easier for vendors to develop systems to respond one at a time
Future of RFID
RFID is a future. RFID has unlimited potential future. Currently, lots of countries are taking RFID technology. The acceptance is rising at a very speedy rate. RFID technology is continuously advancing. RFID not only provides better functionality but also creates more multiple societies. However, as each coin has both sides, RFID technology has a few side effects. The most problem of RFID is privacy of the individual. When the problem is resolved, RFID technology will into everyday functions in the near future.
Successful Examples of RFID
  • About inventory management: Wal-Mart is one of the stronger advocates for widespread use RFID technology to control inventory. Wal-Mart installed RFID readers on the store receiving docks that record the arrival goods by RFID tags. And, some RFID readers are installed in the doorways of the storage room into sales area. Wal-Mart use sales data and RFID system automatically creates a list of goods which need to be restocked from the storage room or shipped from the manufacturers. Generally speaking, Wal-Mart save uncountable dollars in labor and product cost by using RFID technology.
  • About anti-smuggling and cargo management: The cargo RFID e-Seal provided by Alexan Tech Inc., is completely created under the original ISO/PAS 17712 high security seal standard, E- seal is kind of passively abandoned electronic seal. By using Alexan RFID e-seal, it can enable the automatic customs clearance, eliminating smuggling through cargo and fully cargo management, therefore enhancing the efficiency and national competitiveness. Alexan RFID e-seal had presented regarding to experience of using this e-seal for the Customs Control on Transit Containers by Taiwan government at 28th APEC meeting in Singapore on Feb., 2009.
  • About distribution management: The Coca-Cola Company, the world's largest beverage company, markets four of the world’s top five soft drink brands, and a wide range of other beverages. The Coca- Cola Company innovate a machine- Freestyle, which integrate RFID technology to offer over 100 different beverages in a machine. Each individual cartridge, the key to the large drink selection, comes from the plant marked with a passive RFID tag. Readers within the machine track the cartridges and ensure that they are installed properly and keep tabs on their contents, it thus the machine’s success.
  • About security management for specific area: The RFID system of security management provided by Alexan Tech Inc., is can be used for security management in the nursing house, elementary school, and other campuses or sections. By using Alexan RFID security system, it can monitor and control environment for people to prevent harm and so on.
  • About pharmaceuticals management: Pharmaceutical company, OxyContin, have embedded RFID tags in drug containers to track and avert the stealing of highly controlled drugs.
  • About account management: Visa card is combining smart cards and RFID tags so people can conduct transactions without using cash.
  • About tracking application: The United Nations uses RFID technology to track the movements of its personnel. And Continental Airlines uses RFID tags to track passenger bags to reduce the number of lost luggage and make it easier to route luggage.
RFID Relative Links
The Leading Brand of RFID Reader
The Leading Manufacturer of RFID Reader
The Leading Manufacturer of RFID Tag
The Leading Manufacturer of RFID E-seal
The Leading Manufacturer of RFID Systems
RFID Glossary

Active RFID tag: This kind of RFID tag is known as a battery-assisted tag, it needs battery powered, though they may gather energy from other power sources. Active RFID tags transmit a signal to a reader and can be read over 100 feet.

Agile reader: An agile reader can read tags at different frequencies or using different methods of communication between RFID tag (transponder) and reader (interrogator).

Antenna: The element that enables an RFID tag to send and receive data.

Automatic identification and data capture: Technology associated with the acquisition of machine-readable information and creation. For example, bar codes and radio frequency identification (RFID).

Battery-assisted RFID tag: This kind of RFID tag also known as semi-passive RFID tag, it incorporate batteries and use the battery power to run the tag circuitry and sometimes an onboard sensor.

Concentrator: A device that communicates with some RFID readers for the purpose of gathering data, which passes on the information to a host computer.

Dead tag: The RFID tag cannot be read by a reader.

Electronic Product Code™ (EPC): Electronic product code (EPC) is an identification scheme for university identifying physical objects via RFID tags or other items. And, it is a serial number created by the Auto-ID Center that will complement barcodes.

Electronic Seal: Electronic seal (E-Seal) consist of a metal locking bolt with a plastic case that holds the RFID tag linked to a sensor. Electronic seals enable computers to authenticate that data or electronic massages have not been altered, providing a level of security in digital communication.

EPCglobal Inc. ™: This is a non-profit organization between EAN International and the Uniform Code Council, Inc. The EPCglobal is leading the development of industry-driven standards for the Electronic Product Code™ (EPC) to support the use of Radio Frequency Identification (RFID).

Fixed reader: An RFID reader (interrogator) mounted to a permanent or non-mobile structure enabling users to read RFID tag data attached to movable items.

Frequency: Frequency is not only the number of occurrences of a repeating event per unit time but also referred to as temporal frequency. One Hz equals one complete waveform in one second. RFID tags utilize low, high, and ultra-high and microwave frequencies.

Geographical information system (GIS): A geographic information system (GIS) or geographical information system captures, stores, analyzes, and presents data that is linked to location. Basically, a GIS is a system that includes mapping software and its application to remote sensing, land surveying, photography, mathematics, geography, and tools that can be implemented with GIS software.

Global location number (GLN): The Global Location Number (GLN) is part of the GS1 systems of standards. It is a simple tool used to identify a location and can identify locations uniquely where required.

Global trade item number (GTIN): Global Trade Item Number (GTIN) is an identifier for trade items developed by GS1.The standardized system for identifying objects and services created by the Uniform Code Council and EAN International.

GS1 (Global Standard One): GS1 is an international non profit organization dedicated to the development of global standards and solutions to improve the efficiency as well as visibility of supply and demand chains globally and across multiple sectors. The GS1 System of standards is the most widely-used supply-chain standards system in the world.

High frequency RFID tag (HF RFID tag): High frequency (HF) tag generally operates at 13.56 MHz. It can be read from less than 3 feet away and transmit information faster than low frequency (LF) tags.

Interposer: A device connecting an RFID microchip to an antenna to create an RFID transponder.

Low frequency RFID tag (LF RFID tag): This kind of tag generally operates at 125 to 134.2 KHz frequency. The drawbacks of low frequency (LF) tag are they have to be read from within three feet and information transfer speeds are slow, they are less subject to interference than ultra-high frequency UHF tags.

Microwave RFID tag: This kind of RFID tag can operate at 1 to 5.8 GHz (above 415 MHz), it has very high rates and can be read up to 30 feet, but is costly and us e a lot of power and expensive.

Mobile reader: This RFID interrogator is easily transported, allowing people to read RFID tags in a warehouse or other setting along the supply chain.

Near-field communication (NFC): Near- field communication is a short range and high frequency wireless communication technology that enables to exchange of data between devices over about four inches distance. RFID tags closer then one full wavelength away from the tag reader are said to be “near field”, while more than one full wavelength away is “far field”.

Object names (naming) service (ONS): This is a component of the EPCglobal Network and a system for looking up unique Electronic Product Code (EPCs) and information about the item associated with the code.

Passive RFID tag: The sort of tag has no power supply, instead, powered by an incoming radio frequency. And, passive RFID tag is read at relatively short-range from a distance of ten millimeters to over six meters away.

Portal: An RFID reader gateway that tagged items to moved through a portal reader to collect RFID tag data.

Radio frequency identification (RFID): Radio frequency identification (RFID) is a technique for using radio waves to identify the objects. A RFID system consists of an antenna and a transceiver to read the radio frequency as well as transfer the data to a processing device (reader), and a transponder (tag) that is an integrated circuit containing the radio frequency circuitry and information to be transmitted.

Reader: Reader also called interrogator- a device used to communicate with RFID tags and it has one or more antennas that can emit radio waves and received a signal back from the tag.

Read-only RFID tag: This kind of RFID tag cannot be changed unless the tag is electronically reprogrammed.

Read range: The distance from which tag readers can accurately and reliably communication with RFID tags.

Read-write RFID tag: This sort of RFID tag can store new data, often used on reusable containers and other storage assets.

RFID tag: A microchip attached to an antenna and packaged so that it can be attached to an object. There are three kinds of RFID tags, active, passive and semi-passive tag.

Scanner: An electronic device, such as an RFID tag reader, that sends and receives radio waves (frequency).

Semi-passive tag: Semi-passive RFID tags are similar to Active RFID tags- battery powered, yet, it only uses for internal power from RF energy from the reader to broadcast the reply’s signal to reader.

Smart card: A smart card, chip or integrated circuit card (IC card), is any pocket-sized card with embedded integrated circuits which can process data. A contactless smart card uses RFID technology to send and receive data.

Smart reader: A reader that can filter data, execute commands and perform functions similar to a personal computer.

Tag: A microchip attached to an antenna and packaged so that it can be attached to an object.

Tracking: This is the most common RFID tag application.

Transponder: A transponder working on a RFID basis is attached the athlete and a unique code that is detected by radio receivers located at the strategic points in an event.

Ultra-high frequency RFID tag (UHF RFID tag): The Ultra-high frequency (UHF) RFID operates at round 860 MHz to 960 MHz frequency and can read at long distances, up to 15 feet.

Uniform Code Council, Inc.: The Uniform Code Council, Inc. - non-profit organization, dedicated to the implementation and development of standards, global supply chain solutions.

Wavelength: The wavelength is the spatial period of the wave – the distance over which the wave's shape repeats.

Write range: The maximum distance over which data can be written to an RFID tag.

 Copyright © 2009 Alexan Tech. Inc.