| TACAN |
Tactical Air Navigation System |
| TACS |
Total Access Communications System |
| TAG |
Technical Advisory Group |
| TAI |
Temps Atomique International |
| TAPC |
Terrestrial Aeronautical Public Correspondence = TFTS |
| T-DAB |
Terrestrial Digital Audio Broadcasting |
| TBR |
Technical Base for Regulation (ETSI) |
| TCAM |
Telecommunications Conformity Assessment and Market Surveillance Committee (EC) |
| TDD |
Time Division Duplex |
| TDF |
Télédiffusion de France (F) |
| TDM |
Time Division Multiplex |
| TDMA |
Time Division Multiple Access |
| TDRS |
Tracking and Data Relay Satellite |
| TDRSS |
Tracking and Data Relay Satellite System |
| TDWR |
Terminal Doppler Weather Radar |
| TEDS |
TETRA Enhanced Data Service |
| TETRA |
Trans European Trunked Radio |
| TETRAPOL |
A PMR technology |
| TFTS |
Terrestrial Flight Telephone System (= APC) |
| TG |
Task Group (ITU) |
| TIA |
Telecommunication Industry Association (USA) |
| TICT |
Transport Information and Control systems |
| TLSI |
Tracing Lost and Stolen Items |
| TMN |
Telecommunication Management Network (ITU) |
| TMO |
Trunked Mode Operation |
| TOVS |
TIROS Operational Vertical Sounder (NOAA) |
| TPC |
Transmitter Power Control |
| TRRL |
Tactical Radio Link |
| TSAG |
Technical Standardization Advisory Group (ITU) |
| TSLI |
Tracing Stolen and Lost Items |
| TTC |
Tracking, telemetry, and command |
| TV |
TeleVision |
| TWIM |
Terrestrial Wireless Interactive Multimedia applications |
| TWTA |
Travelling Wave Tube Amplifiers |
Committee on Radio Astronomy Frequencies