A radio repeater is a combination of a
radio receiver and a radio transmitter that receives a weak or low-level signal
and retransmits it at a higher level or higher power, so that the signal can
cover longer distances without degradation. This article refers to professional,
commercial, and government radio systems.
In
dispatching,
amateur radio, and
emergency services communications, repeaters are used extensively to relay
radio signals across a wider area. With most emergency (and some other)
dispatching systems, the repeater is
synonymous
with the
base
station, which performs both functions. This includes
police,
fire brigade,
ambulance,
taxicab,
tow truck,
and other services. The civilian
GMRS service in the United States and
UHF CB service
in Australia also use repeaters in much the same fashion as amateur radio
operators do; however, the Canadian GMRS service is an expansion of the
Family Radio Service and is designed to operate simplex-only.