G/TT (G upon T)

Gain-to-noise-Temperature ration of a receiving system; its sensitivity "Figure of Merit".

GIT (G over T)

Gain-to-noise-Temperature ratio of receiving system; its sensitivity or "figure of merit". The higher the GIT better the reception capability of earth station.

GaAs

Gallium Arsenide. High-mobility semicoductor material used in low-noise microwave devices.

Gain

The amount of amplification of input to output power often expressed as a multiplicative factor or in decibels.

Gateway

A network accesspoint. An interchange between two networks, for instance between national and international telecommunications networks (INTELSAT Gateway).

Gauge

A term used to denote the physical size of a wire.

GEO

The Geosynchronous Equatorial (Ciarke) Orbit. Unique orbit in which a body can remain essentially stationary relative to Earth coordinates.

Geosynchronous

Prograde orbit having a period equal to that of the Earth's rotation (need not imply geostationary).

Geosynchronous Orbit

The orbit directly above the equator, about 35,800 kilometers (22,300 miles) above the earth in space. Also known as GEO, geostationary and Clarke orbit. When positioned in this orbit, a satellite appears to hover over the same spot on the earth because it is moving at a rate that matches the speed of the earth's rotation on its axis.

GHz

Unit of frequency equal to 1000 MHz, one billion (10 °) cycles per second.

Giga

A numerical prefix denoting one billion (10 °).

Global Beam

Beam covering the entire visible Earth surface, (42 percent of the globe) as seen from the satellite.

GMT

Greenwich Mean Time. The international universal standard time

Gorizont ("Horizon")

Russian FSS satellites serving the STATSIONAR system in the C- and Ku-bands.

Gregorian

Dual-reflector antenna geometry using a concave ellipsoidal subreflector and paraboloidal main reflector.

Ground

A conducting connection between an electrical circuit and the earth or other large conducting body to sieve as an earth thus making a complete electrical circuit.

Ground Noise

Unwanted microwave signals generated from the warm ground and detected by a dish.

Group Delay

A signal distortion parameter.

GTO

Geostationary (Geosynchronous) Transfer Orbit.

Guard Band

An unused spectra of frequencies which lie above and below each transponder. The guard band helps to prevent adjacent communications signals from interfering with one another.