Gain to Noise Temperature (G/T) is the ratio of gain to temperature-dependent noise and describes the efficiency of satellite receivers and transponders.
The gain-to-noise value is also referred to as the reception quality factor. Gain (G) is the total gain in decibels and "T" is the noise temperature in decibels, referred to 10 Kelvin.
The lower the G/T ratio, the better the satellite reception conditions. In addition, the G/T value indicates the quality of parabolic antennas. Satellite operators publish G/T maps showing the transmission conditions from ground stations to the satellite.