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Land mobile radio systems use channels in the VHF or UHF bands, since the antennas used at these short wavelengths are small enough to mount on vehicles or handheld transceivers. Transmitter power is usually limited to a few watts, to provide a reliable working range on the order of 3 to 20 miles (4.8 to 32 km) depending on terrain.
The first formal specification was approved in 2005, and the first RV-C products were marketed at that time. The RVIA has continued to refine and expand the protocol, and in 2008 applied to ISO with the intention of opening the RV-C protocol to the world community. In 2006 the first RV-C-equipped RVs were sold in America.
The radio set is a mobile terminal that can transmit up to 40 miles (64 km) straight line-of-sight at up to 1 watt, using a traveling wave tube amplifier, or 96 miles (154 km) in tropospheric scatter at up to 1 kilowatt, using a tunable klystron amplifier, at a frequency range of 4.4 to 5 gigahertz and 1.2 to 2.2 gigahertz.
Long-distance calling from landlines was opened to competition in the early 1990s and the use of long-distance revenue to subsidise local service was phased out a few years later. It is not possible for mobile telephone subscribers or coin-paid telephone users to select a default carrier, so long-distance calls are often priced higher from ...
Note 2: "Long-haul communications" usually pertains to the U.S. Defense Communications System. Note 3: "Long-haul telecommunications technicians" can be translated into many fields of IT work within the corporate industry (Information Technology, Network Technician, Telecommunication Specialist, It Support, and so on). While the term is used in ...
Most of the growth in long-range radio communications since 2002 has been in the license-free bands (mostly 900 MHz, 2.4 GHz and 5.8 GHz). Global Pacific Internet and Innetix started wireless service in California in 1995 using Breezecom (Alvarion) frequency-hopping radio, which later became the standard 802.11. [citation needed]
With communication satellites used for long-distance communication links, current troposcatter systems are employed over shorter distances than previous systems, use smaller antennas and amplifiers, and have much higher bandwidth capabilities. Typical distances are between 50 and 250 kilometres (31 and 155 mi), though greater distances can be ...
In telecommunications, a long line is a transmission line in a long-distance communications network such as carrier systems, microwave radio relay links, geosynchronous satellite links, underground cables, aerial cables and open wire, and Submarine communications cables.