Composite material – A material that is made of multiple materials. The composite material combines strengths of multiple materials to produce a new material with better properties than the materials haveindividually.

Electrically thin radome – Single layer radome where the layer is less than 0.1 wavelengths thick at the frequency of interest.

Half-wave radome - Single layer radome where the layer is 0.5 wavelengths thick at the frequency of interest.

A-sandwich – A radome configuration consisting of a low dielectric core, with high dielectric skins on either side.

C-sandwich – A five-layer radome configuration with three skins having high dielectric constant, and two cores with a low dielectric constant.

Gain - The ratio of the power density of an antenna’s radiation pattern in the direction of strongest radiation to that of a reference antenna. The ability to focus an RF signal.

G/T – Figure of merit for satellite antennas similar to signal to noise ratio. Stands for gain/ temperature, where temperature is the noise temperature in Kelvin.

Insertion loss – Total energy loss due to reflection and absorption loss.

Reflection loss – Energy lost because it is reflected by the radome.

Absorption loss – Energy lost because it is absorbed and converted to heat due to dielectric loss.