| O and M |
Operation and Maintenance |
| OAS |
Orbit Adjust Subsystem |
| OB |
Outside Broadcast |
| OBE |
Out of Band Emission |
| OBM |
Outbound Multiplexer |
| OBN |
Out of Band Noise |
| OBO |
Output Back Off |
| OBP |
On Board Processing |
| OCC |
Operation Control Centre |
| ODU |
Outdoor Unit |
| OECD |
Organisation for Economic Cooperation and Development |
| OEM |
Original Equipment Manufacturer |
| OFDM |
Orthogonal Frequency Division Multiplex |
| OFDMA |
Orthogonal Frequency Division Multiple Access |
| OFHC |
Oxygen Free High Conductivity Copper |
| OFT |
Orbital Flight Test |
| OGO |
Orbiting Geophysical Observatory |
| OGSE |
Optical Ground Support Equipment |
| OLIT |
Orbital Launch Integration Tower |
| OMS |
Orbital Manoeuvring System |
| OMT |
Ortho Mode Transducer |
| OMT |
Ortho Mode Transition |
| OMUX |
Output Multiplexer |
| OOK |
On Off Keying |
| OPBO |
Output Power Back Off |
| OPIP |
Output Power Intercept Point |
| OPSK |
Octal Phase Shift Keying |
| OQPSK |
Offset QPSK |
| ORB |
Obeyed Reference Burst |
| ORBIS |
Orbiting Radio Beacon Ionospheric Satellite |
| ORSC |
Oxidiser Rich Staged Combustion |
| Osc |
Oscillator |
| OSD |
Operational Service Date |
| OSI |
Open Systems Interconnection |
| OSM |
Operations Safety Manager |
| OSN |
Output Switch Network |
| OSR |
Orbital Solar Reflector |
| OSS |
Operational Support System |
| OTV |
Orbital Test Vehicle |
| OTV |
Orbital Transfer Vehicle |
| OUB |
Occasional Use Bands |
| OW |
Orderwire |
