| I |
Inspection |
| IAD |
Inflatable Aerodynamic Decelerator |
| IAF |
International Astronautical Federation |
| IAGA |
International Association of Geomagnetism and Astronomy |
| IAM |
International Address Message |
| IAMAP |
International Association of Meteorology and Atmospheric Physics |
| IAI2 |
Inmarsat Air Interface-2 |
| IAP |
Initial Acquisition Phase |
| IBI |
Intergovernmental Bureau for Informatics |
| IBG |
Inbound Group |
| IBO |
Instantaneous Bandwidth |
| IBS |
Intelsat Business Service |
| IBTO |
International Broadcasting and Television Organisation |
| IC |
Integrated Circuit |
| IC |
International Channel |
| ICAO |
International Civil Aviation Organisation |
| ICC |
International Chamber of Commerce |
| ICD |
Interface Control Document |
| ICN |
Idle Channel Noise |
| ICNIRP |
International Commission on Non-ionising Radiation Protection |
| ICO |
Intermediate Circular Orbit |
| ICRF |
International Celestial Reference Frame |
| ICRP |
International Commission for Radiological Protection |
| ICRS |
International Celestial Reference System |
| ICSC |
Interim Communications Satellite Committee |
| ICSU |
International Council of Scientific Unions |
| ID |
Identification |
| ID |
Identifier |
| IDA |
International Development Association |
| IDCC |
International Data Coordination Centres |
| IDD |
International Direct Dial |
| IDF |
Intermediate Distribution Frame |
| IDFT |
Inverse Discrete Fourier Transform |
| IDIQ |
Indefinite Delivery Indefinite Quantity |
| IDP |
Integrated Data Processing |
| IDR |
Intermediate Data Rate |
| IDS |
IF Distribution System |
| IDS |
International Data Service |
| IDU |
Indoor Unit |
| IE |
Index Error |
| IEC |
International Electrotechnical Commission |
| IEEE |
Institute of Electrical and Electronic Engineers |
| IERS |
International Earth Rotation and Reference System |
| IESS |
Intelsat Earth Station Standard |
| IETF |
Internet Engineering Task Force |
| IETS |
Interim European Telecommunications Standard |
| IF |
Intermediate Frequency |
| I/F |
Interface |
| IFA |
In Flight Abort |
| IFC |
In Flight Connectivity |
| IFL |
Interfacility Link |
| IFRB |
International Frequency Registration Board |
| IIP |
Instantaneous Impact Point |
| IISL |
International Institute of Space Law |
| IL |
Interleave |
| ILC |
Initial Launch Capability |
| ILD |
Injection Laser Diode |
| IM |
Initial Mass |
| IM |
Intermodulation |
| IMBU |
Integrated Modem and Baseband Unit |
| IMD |
Intermodulation Distortion |
| IMMAT |
Impedance Matched Multi-Axis Test |
| IMO |
International Maritime Organisation |
| IMP |
Intermodulation Products |
| Impd |
Impedance |
| IMR |
Intermediate Module Repeater |
| IMR |
Intermodulation Rejection |
| IMU |
Inertial Measurement Unit |
| IMUX |
Input Multiplexer |
| Inc |
Inclination |
| InGaP |
Indium Gallium Phosphide |
| INS |
Inertial Navigation System |
| INU |
Inertial Navigation Unit |
| I/O |
Input/Output |
| IOCTF |
IOC TDMA Facility |
| IOP |
Input/Output Processor |
| IOR |
Indian Ocean Region |
| IoT |
Internet of Things |
| IOT |
In Orbit Test |
| IOTS |
In Orbit Test System |
| IP |
Internet Protocol |
| IPA |
Intermediate Power Amplifier |
| IPBO |
Input Power Back Off |
| IPDS |
Inmarsat Packet Data Service |
| IPE |
Internet Protocol Encapsulator |
| IPOLL |
Initial Poll |
| IPPSD |
IP Packet Switched Data Bearer Service |
| IPR |
Intellectual Property Rights |
| IPS |
Input Processing and Service Request Generation Block |
| IPS |
Instrument Pointing System |
| IPU |
Instrument Power Unit |
| IPX |
Internet Packet Exchange |
| IR |
Infrared |
| IRD |
Integrated Receiver Decoder |
| IRIG |
Inter-Range Instrumentation Group |
| IRS |
Integrated Reception System |
| IRT |
Independent Review Team |
| ISAM |
In-space Servicing, Assembly and Manufacturing |
| ISAP |
In Situ Air Production |
| ISEP |
In Situ Electricity Production |
| ISEP |
In Situ Energy Production |
| ISFP |
In Situ Food Production |
| ISB |
Independent Sideband |
| ISC |
International Switching Centre |
| ISCC |
International Service Coordinating Centre |
| ISD |
International Subscriber Dialing |
| ISDN |
Integrated Services Digital Network |
| ISI |
Intersymbol Interference |
| ISL |
Intersatellite Link |
| ISL |
Interstation Signalling Link |
| ISM |
Interstellar Medium |
| ISMC |
International Switching Maintenance Centre |
| ISN |
Input Switch Network |
| ISO |
International Standards Organisation |
| ISOE |
Integrated Sequence Of Events |
| ISOG |
International Satellite Operators Group |
| ISP |
Internet Service Provider |
| Isp |
Specific Impulse |
| ISPIC |
Inmarsat Service Provider Identification Code |
| ISPP |
In Situ Propellant Production |
| ISPRS |
International Society for Photogrammetry and Remote Sensing |
| ISRU |
In Situ Resource Utilisation |
| ISRU |
In-Space Resource Utilisation |
| ISS |
International Space Station |
| ISS |
Interrupt Safety Systems |
| ISS |
Inter-Satellite Service |
| ISTC |
Integrated System Test |
| ISWP |
In Situ Water Production |
| ITA |
International Telegraph Alphabet |
| ITAR |
International Traffic in Arms Regulation |
| ITT |
Invitation To Tender |
| ITU |
International Telecommunications Union |
| ITV |
Interactive TV |
| IUCAF |
Inter Union Commission of Allocation of Frequencies for Radio |
| IUGG |
International Union of Geodesy and Geophysics |
| IUS |
Interim Upper Stage |
| IXC |
Interchange Channel |
