EmbroideredTableCloth: GSM Fixed Phone

Until 1982, the main civil telecommunications system in the UK was a state monopoly known as Post Office Telecommunications. Broadcasting of radio and television was a duopoly of the BBC and Independent Broadcasting Authority : these two organisations controlled all broadcast services, and directly owned and operated the broadcast transmitter sites. Mobile phone and Internet services did not then exist.
The civil telecomms monopoly ended when Mercury Communications arrived in 1983. The Post Office system evolved into British Telecom and was privatised in 1984.
Broadcast transmitters, which belonged to the BBC and IBA, were privatised during the 1990s and now belong to National Grid Wireless, VT Communications and Arqiva.
Regulation of communications has changed many times during the same period, and most of the bodies have been merged into Ofcom, the independent regulator and competition authority for the UK communications industries .
All communications trunks are now digital. Most are carried via national optical fibre networks. There are several companies with national fibre networks, including BT, Virgin Media, Cable & Wireless, Easynet and Thus. Microwave links are used up to the 155 Mbit/s level, but are seldom cost-effective at higher bit rates.
The UK is a focal point for many of the world's submarine communications cables, which are now mostly digital optical fibre cables. There are many satellite links too, but these now provide a relatively small part of the international bandwidth.

EmbroideredTableCloth

2008年12月13日星期六

GSM Fixed Phone

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