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Freeview

From Academic Kids

Freeview is a free-to-air digital television service in the United Kingdom broadcast from terrestrial transmitters using the DVB-T standard. Launched on October 30 2002 at 6am, it took over the DTT licence on 4 multiplexes to broadcast from the defunct ITV Digital.

Unlike ITV Digital and the cable and satellite digital TV services, it offers no subscription, premium or pay-per-view channels. All that is needed to receive the Freeview service is a set-top box costing around 30 to 100, or a new television with an integrated digital tuner. An annual television licence fee is levied for the service, the same fee that covers the analogue channels.

The Freeview consortium consists of the BBC, Crown Castle UK (part of National Grid Transco), and British Sky Broadcasting. The service broadcasts free-to-air television channels, radio stations and interactive services from the BBC, Sky and various other broadcasters. In March 2005, ITV and Channel 4, joint owners of multiplex 2, were invited to join the Freeview consortium [1] (http://www.digitalspy.co.uk/article/ds19874.html) [2] (http://www.dtg.org.uk/news/news.php?id=729).

It is commonly and incorrectly believed Freeview consists of the whole of the UK DTT platform. A subscription based service, Top Up TV launched in March 2004 using unused channel space. The Top Up TV service is not a part of the Freeview service; it runs alongside it on the DTT platform. Additionally, services on Multiplex 2 (Digital 3 and 4) and Multiplex A (SDN) are not part of the Freeview service, although they are often advertised as being part of Freeview.

At the end of 2004, it was reported that over 5 million households in the UK have Freeview, making it the second most popular digital TV format in the UK.

Contents

Full list of Freeview TV channels

See also: List of UK Digital Terrestrial television channels

Full list of Freeview radio stations

See also: List of UK Digital Terrestrial radio channels

The multiplexes

Digital Terrestrial channels in the United Kingdom are broadcast in six groups, or multiplexes (sometimes abbreviated mux) - the multiplexes are labelled 1, 2, A, B, C & D. Each multiplex represents a certain amount of bandwidth, which can be used for any combination of compressed video, audio and data. Within a multiplex it is possible to make trade offs between the number of channels and the quality of the picture and audio. Each of these multiplexes was given to the control of a different company, and they uniformly decided to go for quantity of channels over quality of service. Many grumpy engineers of the old school, bought up to believe in producing a high quality service, as well as members of the public with modern hi-fis and large television sets, are not terribly impressed by this.

When the British government allocated the multiplexes, it gave half the capacity on a multiplex to each existing analogue terrestrial broadcaster. This meant the BBC got a multiplex to themselves, ITV and Channel 4 shared the second, five and S4C shared the third. The remaining space was then auctioned off. A consortium of Granada and Carlton (then members of the ITV network, now merged) along with BSkyB successfully bid for, and set-up, the OnDigital (later ITV Digital) service. ITV Digital collapsed in a messy cloud of football and recriminations in 2002. The multiplexes were consequently taken over by a consortia of the BBC, CCI (who operate the transmission network) and BSkyB. In May 2004, a new service (Top Up TV) was launched to provide subscription content in unused space on Multiplexes 2 and A.

Multiplex 1 - BBC
TV: BBC ONE, BBC TWO (Not in Wales), BBC 2W (Wales Only), BBC THREE, CBBC Channel, BBC News 24
Radio: BBC Radio Scotland and BBC Radio nan Gaidheal (Scotland Only), BBC Radio Ulster and BBC Radio Foyle (Northern Ireland Only), BBC Radio Wales and BBC Radio Cymru (Wales Only)
Interactive Services: BBCi

Multiplex 2 - Digital 3 and 4 (Not Freeview)
TV: ITV1, ITV2, ITV3, Channel 4, GMTV, GMTV 2, UKTV Food*, E4, Bloomberg*, ITV News
Interactive Services: Teletext on 4, Teletext, 705 (Carrying the live video stream of Big Brother)

Multiplex A - ITV PLC (Not Freeview)
TV: five, abc1 (Not in Wales), S4C (Wales Only), S4C~2 (Wales Only), Tele-G (Scotland Only), QVC, bid.tv, UKTV Gold*, TCM*, Boomerang*, Cartoon Network*, Discovery*, Discovery Real Time*, Television X*, UKTV Style*, Screenshop, price-drop.tv, Screenshop 2, Xtraview
Radio: BBC Radio 1 (England version), 2, 3, 4 (FM version), Mojo, Heat.

Multiplex B - BBC
TV: BBC Four, CBeebies, BBC Parliament, News loops (Available via BBCi), Community Channel
Radio: BBC 1Xtra, BBC Radio Five Live, BBC Five Live Sports Extra, BBC 6 Music, BBC 7, BBC Asian Network
Interactive: BBCi {extra content}, "701", "702", "703" (carrying BBC Parliament and the News Loops)

Multiplex C - CCI
TV: Sky Travel, Sky News, UKTV History, Sky Sports News, E4 +1
Radio: talkSPORT, 3C, Premier Radio

Multiplex D - CCI
TV: UKTV Bright Ideas, The Hits, ftn, TMF, Thomas Cook TV, Ideal World, Men & Motors
Radio: BBC World Service (Europe), The Hits Radio, Smash Hits!, Kiss 100, Magic 105.4, Q, Oneword, Jazz FM 102.2, Kerrang!)

* indicates a Pay TV service

Use of multiplexing technology

The astute reader will notice that some of these multiplexes carry a much larger number of services than others. Firstly, a number of services share bandwidth - so some channels turn off when others are on. (For example you will never see BBC Four and CBeebies together in the same room, as they use the same space in Multiplex B.) In addition, some multiplexes have fewer channels so as to allocate more data to fewer services, thus ensuring higher quality (for example, BBC One on Multiplex 1 is carried as a 5.5 Megabit stream, while Sky Sports News uses 2 Megabits per second.)

On top of this, the modulation of the multiplexes can be varied to squeeze higher digital bitrates out of the same portion of the electromagnetic spectrum. This comes at the cost of making it harder to get a good signal. There are three basic modulation schemes currently in use in the UK; in order of bandwidth efficiency, they are: QPSK (only used for tests in the Oxford and London areas), 16 QAM and 64 QAM, each with a progressively higher bitrate, at the cost of progressively higher likelihood of signal degradation. Currently multiplexes 2 and A use 64 QAM (and are consequently more prone to poor reception) while the other multiplexes all currently use 16 QAM.

Furthermore, multiplexes can make use of statistical multiplexing at the MPEG video coder whereby the bitrate allocated to a channel within the multiplex can vary dynamically depending on how difficult it is to code the picture content at that precise time, and how much demand there is for bandwidth from other channels. In this way, complex pictures with lots of detail may demand a higher bitrate at one instant and this can result in the bitrate allocated to another channel in the same multiplex being reduced if the second channel is currently transmitting pictures which are easier to code, with less fine detail.

New compression technology

New compression technology has opened up two free slots on the Crown Castle multiplex, with the possibility of more to follow on this and other multiplexes. The additional capacity has been achieved by technology developments that have allowed the company to broadcast the additional channels using limited bandwidth. The two slots were made available for bidding earlier this year, and due to the limited capacity on the DTT service in the UK, broadcasters bid in millions in order to gain bandwidth. ITV won the bidding for the first slot (on which it launched Men & Motors on May 2, 2005), and Channel 4 the second. Channel 4 launched E4 +1, as opposed to its new channel More4, on the multiplex when the slot became available on June 1 (E4 launched on Freeview on May 27).

7 Day EPG

As of Monday 26 July 2004 the 7 Day Electronic Programme Guide began to roll out across the country. This technology, tested earlier in the year, means that users are able to view a full week of programme schedules on specially enabled Freeview Boxes.

See also

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