Active tags — Electronic identification tags that use batteries as a partial or complete source of power to transmit the data structure. Normally used in wildlife/endangered species research. (See definition for “passive tags” listed below.)

Antenna — The antenna is the part of the reader/interrogator that radiates the radio frequency energy to, and receives energy from, the transponder.

Alphanumeric — Data comprised of both alphabetical and numeric characters. For example, the data sequence B143F6 represents an alphanumeric string. Often, this term includes other printable characters such as punctuation marks.

Anti-collision (Anti-contention) — A term describing an RFID system's capacity for avoiding conflict at the reader/interrogator for responses arising from transponders simultaneously present within the read/interrogation zone and competing for attention at the same time.

Binary (Bin) — A number in binary code that is always written in groups of four bits, each group represents one digit of the number. For example, 0011 1000 is 38.

Bit — An abbreviation for binary digit. A single element (0,1) in a binary number. ISO standard 11784 details the data structure or bit pattern of data placed on electronic transponders. The numeric structure is arranged on 64 bits that is divided into three primary data fields.

Byte — Eight bits of data

Biometrics — Measurement or observation of a feature or action of an animal such as iris or retinal patterns or DNA for the purposes of uniquely identifying the animal.

Capture field — The region of the electromagnetic field generated by the antenna in which transponders will operate.

Chip — The electronic chip consists of an integrated circuit and a capacitor that is attached to two ends of a coil.

Coil — That component of the electronic chip which consists of very thin wire winded 500 to 1000 times into a loop that has a diameter of 20 to 30 mm.

Collision — A term used to denote an event when two or more transponders are competing for attention from the reader/interrogator at the same time. As a result, data confusion to the interrogator may cause misreading.

Data — Representations — in the form of numbers and characters, for example — to which meaning may be ascribed.

Data accumulator — Any device (be it wired or wireless) such as a laptop or handheld computer or scale head that is capable of accepting data from the reader.

eID — Electronic identification, for example - by line of sight using light (bar code) or radio frequency transmission.

eTag — An animal identification device that contains an electronic chip. Also referred to as a transponder.

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

Full duplex (FDX) — A design principle whereby the return signal initiates as soon as the beginning of the interrogation signal is received and the smoothing capacitor in the transponder has been charged. The return signal is received repetitively and without interruption for as long as a continuous interrogation signal is maintained. An FDX transponder doesn't have to store energy to be able to return its entire data content.

Half duplex (HDX) — A design principle whereby the transponder initiates the return signal to the reader/scanner/interrogator only after the end of the interrogation signal has been received and only after the storage capacitor has been fully charged in the transponder. The return signal is then only sent once, since the transponder has emptied its storage capacitor after it has sent its entire data content.

Herd of origin — Herd of birth

Inductive coupling — Systems that use the inducing of a current into a coil as a means of transferring data or power are said to use inductive coupling.

Information — Something that is meaningful. For example, data may be regarded as information once its meaning is revealed.

Interface — An electrical or physical standard for the interconnection of devices. Some common interfaces include RS232, RS422 or RS485.

Interference — Unwanted electrical signals found in the operating environment of RFID equipment that interfere with the transponder's or reader's normal operation. Obviously, the effect of interference can be seen in reduced system performance.

Interrogator — A fixed or mobile data capture and identification device using a radio frequency electromagnetic field to stimulate and create a coordinated data response from a transponder. Often used as an alternative term to reader, transceiver or scanner.

ISO — International Organization for Standardization (

ISO 11784 — This international standard represents the definition of the data numeric architecture of the 64-bit (character) code for electronic animal identification.

ISO 11785 — This international standard describes the accepted protocol for transmission between the reader/scanner/interrogator and the transponder (tag). The standard consists of two transmission protocols, half duplex (HDX) and full duplex (FDX).

Manufacturer/Country Code — Three-digit code defined by ISO 11784 standard. If country codes are used, ISO 3166 standard is used (USA country code is 840).

Memory modules — Refers to the means of storing data content within the transponder. A variety of random access (RAM), read-only (ROM), write once-read many (WORM) and read/write (RW) memory devices may be noted.

National Institute for Animal Agriculture (NIAA; — NIAA is a new name in animal agriculture, but carries a strong legacy of providing the U.S. livestock industry with a forum to collectively address issues of common interest. The new organization, successor to the Livestock Conservation Institute (LCI), is the result of a progressive process and vision that began in 1996 when LCI's board of directors commissioned a long-range planning team to landscape an organization that would best serve animal agriculture in the 21st century.

Noise disturbance — A cause normally attributed to low data capture around heavily industrialized areas such as packing plant facilities and feedlot processing areas. In such areas, extraneous electromagnetic interference from inflorescence lights and other devices emit conflicting signals from other competing devices.

Noise immunity — An indication of the robustness of a system to operate in the presence of noise disturbance.

Orientation — The alignment of a transponder with respect to the reader antenna.

OTP — One-time programmable — Specific chip design where the device manufacturer programs the contents of the electronic chip. This design is normally done to correlate the electronic identification number with the visual identification number.

Passive tags — In order to transmit tag data content, the reader/scanner/interrogator must “excite” the transponder at a specific radio frequency. RFID tags that rely upon the energy generated from the magnetic field induced by the reader/scanner/interrogator in order to transmit tag data content. (See definition for “active tags” listed above.)

Process verification — The ability to verify whether an animal has received a specific product (such as a vaccine) or procedure (defined set period of weaning) as claimed by the seller.

Range — The distance at which consistent, successful reading and/or writing can be accomplished between the transponder and the reader/interrogator.

Read distance — Refers to the distance between the transponder and the reader antenna. The distance will be affected by the power available to the reader, the power available within the tag to respond and electromagnetic interference.

RFID (radio frequency identification) — Any electronic identification system comprised of a reader/scanner/interrogator and a transponder that can read or write data content using a specified radio frequency.

Reader (interrogator) — The device in a radio frequency system that contains the digital electronics that trigger the transponder to respond, and extracts and validates the information from the transponder's response. (See also interrogator, scanner or transceiver.)

Read only (R/O) — Specific chip design whereby the chip has information written into it during its manufacture. This information can only be read from the tag and can never be changed.

Read/write (R/W) — Specific chip design whereby data can be freely read or written to a transponder using a suitable programming reader.

RS232 — A common physical interface standard for the interconnection of devices. The standard allows for a single device to be connected at baud rates up to 9600 bps, at distances up to 15 meters.

RS422 — An interface standard similar to RS232 except that differential voltages across twisted pair cables are used. This standard is more noise immune than RS232 and is often used to connect single or multiple devices to a data accumulator at distances up to 3,000 meters.

Source verification — The ability to verify the source of animal as claimed by the owner or seller.

Transceiver — The reader/scanner/interrogator device that is used to interrogate/read a transponder.

Transponder — A reference to a radio-frequency identification tag that combines the technical terminology of transmitter (trans) and responder (ponder). The transponder becomes activated when placed inside a magnetic field generated by an antenna. The induced current in the coil in turn charges the capacitor located inside the chip. Depending upon the transfer protocol, the chip transmits its identification code (and attached information if R/W).

Wedge — Software that converts data from a scanner or interrogator into a format that a computer application can use, typically by making scanned data appear as though it were keypunched in.

Write once read many (WORM) — Specific chip design whereby a transponder can be part or totally programmed initially by the user and only read thereafter.