802.11 Standard

A standard carrying out wireless local area network (WLAN) computer communication in the 2.4, 3.6 and 5 GHz frequency bands. It is maintained by the IEEE LAN/MAN Standards Committee (IEEE 802). 802.11 Standard is the basis for Wi-Fi specification. This technology is used by some RTLS solutions to calculate location.

802.15.4 Standard

A standard which specifies the physical layer and media access control for low-rate wireless personal area networks (LR-WPANs). It is maintained by the IEEE 802.15 working group. 802.15.4 Standard is the basis for the ZigBee specification. This technology is used by some RTLS solutions to calculate location.

Active RFID Transponder (Tag)

An RFID tag that has a transmitter to send back information, rather than reflecting back a signal from the reader, as a passive tag does. Most active tags use a battery to transmit a signal to a reader, however, some tags can gather energy from other sources. Active tags can be read from 300 feet (100 meters) or more, but they are more expensive than passive tags. They are used for tracking expensive items over long ranges. For example, the U.S. military uses active tags to track containers of supplies arriving in ports.


Software that utilizes data coming from the middleware and directly interacts with the end user. Examples of applications include: asset tracking and management, patient flow, temperature monitoring, infection control and hand hygiene, staff duress, inventory tracking and management, positive patient identification, business intelligence and reporting and wireless nurse call.

Air Interface Protocol

The rules that govern how tags and readers communicate.


A method of communication between passive tags (ones that do not use batteries to broadcast a signal) and readers. RFID tags using backscatter technology reflect back to the reader radio waves from a reader, usually at the same carrier frequency. The reflected signal is modulated to transmit data.


The range or band of frequencies, defined within the electromagnetic spectrum, that a system is capable of receiving or delivering.


Consist of small images of lines (bars) and spaces affixed to retail store items, ID cards and postal mail to identify a particular product number, person or location. Barcodes are a standard method of identifying the manufacturer and product category of a particular item.  A barcode reader uses a laser beam that is sensitive to the reflections from the line and space thickness and variation. The reader translates information from the image to digital data and sends it to a computer for storage or for another process.  2D barcodes store information not only horizontally, as one-dimensional barcodes do, but vertically as well.  That construction enables 2D codes to store up to 7,089 characters.  The traditional, uni-dimensional barcode has only a 20-character capacity.

Battery-Assisted Passive Tag (BAP)

These are RFID tags with batteries, but they communicate using the same backscatter technique as passive tags (tags with no batteries). They use the battery to run the circuitry on the microchip and sometimes an onboard sensor.  They have a longer read range than a regular passive tag because all of the energy gathered from the reader can be reflected back to the reader. They are sometimes called “semi-passive RFID tags.”


Identify individuals by comparing biological data, such as fingerprints, voice characteristics and iris patterns, against stored data for that individual.  Biometric systems consist of a reader or scanning device, software that converts the scanned biological data into a digital format and compares match points, and a database that stores the biometric data for comparison. Authentication by biometric verification is becoming increasingly common in corporate and public security systems, consumer electronics and point of sale (POS) applications. Specific biometric AIDC (Automatic Identification and Data Capture) technologies include finger-scanning, electro-optical fingerprint recognition, finger vein ID and voice recognition.

Data Retention

The ability of a microchip to maintain the information stored in EEPROM (Electrically Erasable Programmable Read-Only Memory). RFID tags and other microchips can typically retain data for 10 years or more, but data retention depends on temperature, humidity and other factors.

Electromagnetic Spectrum

The range or continuum of electromagnetic radiation, characterized in terms of frequency or wavelength.

Electronic Product Code (EPC)

Provides a unique identity for every physical object anywhere in the world, for all time. Its structure is defined in the GS1 EPCglobal Tag Data Standard, which is an open standard freely available for download from the website of GS1 EPCglobal. The EPC is designed as a flexible framework that can support many existing coding schemes, including many coding schemes currently in use with barcode technology. EPC identifiers currently support 7 identification keys from the GS1 system of identifiers.


A joint venture between GS1 (formerly known as EAN International) and GS1 US (formerly the Uniform Code Council, Inc.). It is an organization set up to achieve worldwide adoption and standardization of Electronic Product Code (EPC) technology.


A process of transmitting radio frequency energy from the RFID tag reader to stimulate a passive RFID tag to provide power to transmit its data back.


The number of cycles a periodic signal executes in unit time. Usually expressed in Hertz (cycles per second) or appropriate weighted units such as kilohertz (kHz), Megahertz (MHz) and Gigahertz (GHz).


GS1’s main activity is the development of the GS1 System, a series of standards designed to improve supply-chain management. The GS1 System is composed of four key standards: Barcodes (used to automatically identify things), eCom (electronic business messaging standards allowing automatic electronic transmission of data), GDSN (Global Data Synchronisation standards which allow business partners to have consistent item data in their systems at the same time) and EPCglobal (which uses RFID technology to immediately track an item).

High-Frequency (HF)

The frequency bandwidth from 3 MHz to 30 MHz. HF RFID tags typically operate at 13.56 MHz, can normally be read from less than 3 feet away, and transmit data faster than low-frequency tags, although they consume more power than low-frequency tags.

Infrared (IR)

A technology that uses electromagnetic radiation with a wavelength that is longer than that of visible light but shorter than that of microwaves and terahertz radiations. The IR signal does not penetrate walls, ceilings, floors or large objects inside a room, but it does bounce off any object in its path. This technology is used to enable RTLS systems.

International Organization for Standardization (ISO)

A non-governmental organization made up of the national standards institutes of 146 countries. Each member country has one representative and the organization maintains a Central Secretariat in Geneva, Switzerland, that coordinates the system. Most RFID related ISO Standards are:

  • ISO 10536: The international standard for proximity cards
  • ISO 11784: The international standard defining frequencies, baud rate, bit coding and data structures of the transponders used for animal identification.
  • ISO 14443: A set of international standards covering proximity smart cards.
  • ISO 15693: The international standard for vicinity smart cards.
  • ISO 18000: A series of international standards for the air interface protocol 
  • used in RFID systems for tagging goods within the supply chain.
  • ISO 7816: A set of international standards covering the basic characteristics of smart cards, such as physical and electrical characteristics, communication protocols and others.


LAN (Local Area Network)

A relatively small network (compared to a WAN) covering small areas like a room, a department, a building, a campus, etc.

Low-Frequency (HF)

The frequency bandwidth from 30 kHz to 300 kHz. Low-frequency RFID tags typically operate at 125 kHz or 134 kHz. Low-frequency RFID tags have to be read from within three feet, and their data transfer rate is slow, but they are less susceptible to interference than UHF tags.


A means of storing data in electronic form. A variety of random access (RAM), read-only (ROM), Write Once-Read Many (WORM) and read/write (RW) memory devices can be distinguished. In RFID terms, it’s the amount of data that can be stored on the microchip in an RFID tag. It can range from 64 bits to 2 kilobytes or more on passive tags.

Microwave Tags

A term that is sometimes used to refer to RFID tags that operate at 5.8 GHz. They have very high transfer rates and can be read from as far as 30 feet away, but they use a lot of power and are expensive. (Some people refer to any tag that operates above about 415 MHz as a microwave tag.)


In the RFID world, this term is generally used to refer to software that resides on a server between readers and enterprise applications. The middleware is used to filter data and pass on only useful information to enterprise applications. Some middleware can also be used to manage readers on a network.



A term to denote the process of superimposing (modulating) channel encoded data or signals onto a radio frequency carrier to enable the data to be effectively coupled or propagated
across an air interface. Also used as an associative term for methods used to modulate carrier waves. Methods generally rely on the variation of key parameter values of amplitude, frequency or phase. Digital modulation methods principally feature amplitude shift keying (ASK), frequency shift keying (FSK), phase shift keying (PSK) or variants.

Near Field Communication (NFC)

Is a set of standards for smartphones and similar devices to establish radio communication with each other by touching them together or bringing them into close proximity, usually no more than a few centimeters/inches. Present and anticipated applications include contactless transactions, data exchange, and simplified setup of more complex communications such as Wi-Fi. Communication is also possible between an NFC device and a passive RFID Transponder (Tag).


Passive Transponder (Tag)

A battery-free data carrying device that reacts to a specific, reader produced, inductively coupled or radiated electromagnetic field, by delivering a data modulated radio frequency response. Having no internal power source, passive transponders derive the power they require to respond from the reader’s electromagnetic field.


A set of rules governing a particular function, such as the flow of data/information in a communication system.

Radio Frequency Identification (RFID)

A technology that incorporates the use of electromagnetic coupling in the RF portion of the electromagnetic spectrum to uniquely identify an object, animal or person.  RFID uses a wireless non-contact radio system to transfer data from a tag attached to an object, for the purposes of automatic identification and tracking.  RFID is coming into increasing use as an alternative to barcode, as it does not require direct contact or line-of-sight scanning.  RFID systems consist of three components – the antenna, the reader or transceiver (often combined into a single device) and a transponder (tag).  The antenna transmits a signal that activates the tag, which then transmits data back to the antenna.  The data is used to notify a programmable logic controller that some specific action should occur.

Read Only

Term applied to a transponder in which the data is stored in an unchangeable manner and can therefore only be read.

Read Range

The distance from which a reader can communicate with a tag. Active tags have a longer read range than passive tags because they use their own power source (usually a battery) to transmit signals to the reader. With passive tags, the read range is influenced by frequency, reader output power, antenna design, and method of powering up the tag. Low-frequency tags use inductive coupling, which requires the tag to be within a few feet of the reader.

Read Rate

The maximum rate at which data can be communicated between transponder and reader/interrogator, usually expressed in bits per second (bps or bits.s-1).


Applied to a radio frequency identification system, it is the ability to both read data from a transponder and to change data (write process) using a suitable programming device. See RFID Reader.


Determines how well a tagged person or item can be tracked to a specific location (e.g., resident room, ER bay).


A technology that uses both radio waves and infrared for identification and tracking purposes. This technology is used to enable some RTLS systems.


The International RFID Business Association (RFIDba) was founded in April 2004 as a not-for-profit, educational, technology and frequency agnostic, trade association dedicated to serving the business needs of the end user community with vendor neutral information on RFID and RTLS technologies along with information on other associated, complimentary technologies.

RFID in Healthcare Consortium

The RFID in Healthcare Consortium (RHCC) is a not-for-profit, subsidiary organization of The International RFID Business Association (RFIDba) and operates under its auspices, guidelines, governance, and by-laws. The Consortium was founded on September 13th, 2008 to initially address EMI issues with RFID & RTLS technologies but has recently transformed itself into a full fledged trade organization. The Consortium is an educationally focused, vendor neutral, technology and frequency agnostic organization dedicated to promoting the use and adoption of RFID and RTLS technologies in the healthcare, assisted living and nursing home industries.

RFID Reader

A device that is used to interrogate a passive RFID Tag. The reader has an RFID antenna that emits radio waves; the tag responds by sending back its data.

RFID Receiver

A device that listens for RF (radio-frequency) signals and converts them into data packets that are available for further processing. It is used with active RFID tags, which continuously emit pre-programmed messages.

RFID Transponder (Tag)

A microchip attached to an antenna that can be applied to an object. The tag picks up signals from and sends signals to an RFID reader. The tag may contain a unique serial number, and may have other information such as a customer account number. Tags come in many forms, such as smart labels that have a barcode printed on them, or the tag can simply be mounted inside a carton or embedded in plastic.  RFID tags can be active, passive or semi-passive.

RTLS (Real-Time Locating System)

Refers to technology that is used to locate and track people and items (such as assets, equipment, inventory) by associating a tag with each person or item. This term is commonly used in reference to “active” locating technologies.

SAW (Surface Acoustic Wave) Devices

Devices using a transponder technology in which low power microwave signals are converted to ultrasonic waves by and on the surface of a piezoelectric crystal material forming the tag. Surface applied ‘finger’ transducers determine the form and data content of the reflected return signal.


An electronic device that senses a physical entity and delivers an electronic signal that can be used for control purposes.

Smart Cards

Plastic cards about the size of a credit card with an embedded microchip. A smart card can store much more data than a magnetic stripe card. It can be loaded with data, used for telephone calling, electronic cash payments, accessing services and other applications. The card can be refreshed for reuse. Some smart cards can include programming and support multiple applications.


An electronic TRANSmitter/resPONDER, commonly referred to as a Tag.

Ultra-high-Frequency (UHF)

The frequency bandwidth from 300 MHz to 3 GHz. Normally, RFID tags that operate between 866 MHz and 960 MHz can send information faster and farther than high- and low-frequency tags.  UHF signals cannot pass through many items with high water content.  UHF tags are generally more expensive than low-frequency tags, and they consume more power.


A technology that uses a cyclic sound pressure with a frequency greater than the upper limit of human hearing. The production of ultrasound is used in Real-Time Location Systems as it can provide room level location accuracy because the sound does not penetrate walls.

Ultra-wide Band (UWB)

Any radio technology having bandwidth exceeding the lesser of 500 MHz or 20% of the arithmetic center frequency. This technology is used to enable RTLS systems.

Stands for Wide Area Network. As its name suggests, it is a computer network that covers a far wider area than a LAN. WANs cover cities, countries, continents and the whole world. A WAN is formed by linking LANs together.


Refers to any system that uses the 802.11 Standard, which was developed by the Institute of Electrical and Electronics Engineers (IEEE). Wi-Fi networks operate in the 2.4 and 5 GHz radio bands, with some products that contain both bands (dual band). Wi-Fi is a very common wireless technology that is used to connect machines in a LAN. This technology is used by some RTLS systems for locating purposes.

Wireless Sensor Network (WSN)

A network of spatially distributed autonomous sensors to cooperatively monitor physical or environmental conditions, such as motion, temperature, pressure, sound, or vibration. In addition to one or more sensors, a sensor network is typically equipped with a radio transceiver or other wireless communications device, a small micro-controller, and an energy source – usually a battery.


The process of transferring data to a transponder, the internal actions of storing the data, which may also encompass the reading of data to verify the data content.

Write Once Read Many (WORM)

Distinguishing a transponder that can be part or totally programmed once by the user, and thereafter only read.

Write Rate

The rate at which data is transferred to a transponder and stored within the memory of the device and verified. The rate is usually expressed as the average number of bits or bytes per second over which the complete transfer is performed.


See 802.15.4 Standard