Glossary of Terms

ADS-B: Automatic Dependent Survelliance Broadcast. Next generation ATC system permitting air to air communication and air traffic coordination without the involvement of a ground station.

AOPA: Aircraft Owners and Pilots Association

ATC: Air Traffic Control

ATCAC: Air Traffic Control Advisory Committee

ATCRBS: Air Traffic Control Radar Beacon System

DABS: Discrete Address Beacon System (aka "Super Beacon", "Mode S")

FAA: Federal Aviation Administration

FRUIT: False Replies Uncorrelated in Time

Garble: data corruption caused by receiving multiple signal replies when only expecting one

IFF: Identify Friend or Foe - a system for electronically differentiating between friendly and enemy aircraft

LL: Lincoln Labs

modulation: the process in which a bitstream is converted to a waveform compatible with a transmission channel

Mode A: Transmission of unique identifer in ATCRBS by planes. Also used in Mode S.

Mode C: Transmission of altitude in ATCRBS by planes. Also used in Mode S.

Mode S: Mode Select - a bidirectional one-to-one data-link for ground to air communication

SLS: Sidelobe Suppression. A technique originally used in ATCRBS and employed in Mode S which temporarily suppress planes from responding to interrogation signals if a plane is hearing the leakage of signal directed to another plane (sidelobe). This prevents planes from responding to signals not intended for them.

TACAN: Tactical Air Navigation System

TCAS: Traffic Collision Avoidance System