TETRA
Terrestrial Trunked Radio (TETRA) is a digital trunked mobile radio standard developed by the European Telecommunications Standards Institute (ETSI). The purpose of the TETRA standard is to meet the needs of traditional Professional Mobile Radio (PMR) user organisations such as those listed below.

• Public Safety
• Transportation
• Utilities
• Government
• Military
• PAMR
• Commercial and Industry
• Oil and Gas

Because the TETRA standard has been specifically developed to meet the needs of a wide variety of traditional PMR user organisations it has a scaleable architecture allowing economic network deployments ranging from single site local area coverage to multiple site wide area national coverage.
Besides meeting the needs of traditional PMR user organisations, the TETRA standard has also been developed to meet the needs of Public Access Mobile Radio (PAMR) operators.