List of abbreviations: A

AAC Aeronautical Administrative Communications
AC/WPBX Advanced Cordless/Wireless Private Branche Exchange
ACTS Advanced Communications Technologies & Services
ADEOS Advanced Earth Exploration Satellite
ADM Administrative
ADS Advanced Digital System
ADS Automatic Dependent Surveillance (USA)
AEA European Airline Association
AeFS Aeronautical Fixed Service
AGA Air-Ground-Air
AeM Aeronautical Mobile Service
AeM(OR) Aeronautical Mobile Service (off-route)
AeM(R) Aeronautical Mobile Service (route)
AeMS Aeronautical Mobile Service
AeMSS Aeronautical Mobile Satellite Service
AeMSS(OR) Aeronautical Mobile Satellite Service (off-route)
AeMSS(R) Aeronautical Mobile Satellite Service (route)
AeRNS Aeronautical Radionavigation Service
AeRNSS Aeronautical Radionavigation-Satellite Service
AFSCN Air Force Satellite Control Network (USA)
AIS Automatic Ship Identification and Surveillance System
AmS Amateur Service
AMSAT Radio Amateur Satellite
AMSC American Mobile Satellite Corporation (USA)
AMSS Aeronautical Mobile-Satellite Service
AmSS Amateur-Satellite Service
ANACOM Autoridade Nacional de COmunicações (Portugal)
ANFR Agence National des Fréquences Radioélectriques (F)
ANS Air Navigation System
ANSI American National Standards Institute (USA)
AOC Aeronautical Operational Control
APC Aeronautical Public Correspondence = TFTS
APC American Personal Communications (USA)
APCO Association of Public-Safety Communications Officials-International, Inc. (USA)
API Advance Publication Information (ITU-R)
APRII Accounting Principles And Regulatory Interconnection Issues (CEPT)
APT Asia-Pacific Telecommunity
ARC Administrative Radio Conference
ARFA Allied Radio Frequency Agency
ARIA Advanced Range Instrumentation Aircraft (USA)
ARSR Air Route Surveillance Radar
ART Authorité de Régulation des Télécommunications (F)
ASA Austrian Space Agency (A)
ASDE Airport Surface Detection Equipment
ASK Amplitude Shift Keying
ASMS Advanced Satellite Mobile Systems
ASMS-TF Task Force on Advanced Satellite Mobile Systems
ASO Australian Space Office (Aus)
ASPG Arab Spectrum Management Group
ASTAP Asia-Pacific Telecommunity Standardization Program (APT)
ASTRON Netherlands Foundation for Research in Astronomy (NL)
ASV Advanced Safety Vehicle System
ATC Air Traffic Control
ATC Ancillary Terrestrial Component
ATDRS Advanced Tracking and Data Relay Satellite
ATDRSS Advanced Tracking and Data Relay Satellite System
AT-EZ Agentschap Telecom – Ministerie Economische Zaken (NL)
ATM Asynchronous Transfer Mode technology
ATN Amateur Television Network (USA)
ATNF Australia Telescope National Facility (Aus)
ATU Arab Telecommunication Union
ATS Air Traffic Services
ATV Amateur Television (USA)
AVI Automatic Vehicle Identification
AVM Automatic Vehicle Monitoring
AWACS Airborne Warning and Control System