Glossary of Electrical, Magnetic, and Other Scientific Terms

Absorption: A certain type of optical attenuation that converts energy waves (such as RF waves) into a different form of energy (such as heat) by interacting with the material properties of an object.

AEN: See Ambient electromagnetic noise.

ALOHA slot: This data transmission protocol was developed for one of the early local area networks. Hailing from the University of Hawaii, it describes a method of transmitting data that avoids data collision.

AM: See Amplitude modulation.

Ambient electromagnetic noise (AEN): Radio signals present in a specific location that need to be identified in order to determine the level of potential interference with an RFID system.

American Standards Code for Information Interchange (ASCII): A binary, 7-bit data encoding scheme comprising 128 codes used to represent all of the upper- and lowercase Latin letters, numbers, punctuation, and so on.

Amplifier: This electronic device increases a signal’s transmitted power. You typically use it in-line between a reader and an antenna if the antenna needs a stronger signal.

Amplitude: The height of a wave.

Amplitude modulation (AM): A signal encoding technique that modifies the amplitude of a radio wave (as opposed to its frequency) depending on the behavior of the signal that it is transporting. By changing the amplitude of a wave, an RFID tag can transmit a binary signal to the reader. The method of changing the amplitude is known ...

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