The BBC and commercial operators are gradually adding DAB transmitters
to the national BBC and Digital One national networks to expand
coverage as far as is economically viable.
While the BBC's national VHF/FM radio transmitter networks enjoy
approximately 98% population coverage, it is likely to be some years
bef re their DAB coverage reaches this figure. However [in 2009] the
authorities stated aim was to switch off all national FM transmitters
by around 2015, suggesting that full nationwide coverage should be
achieved by the DAB network by this time
Economics plays a more important factor in the currently under-utilised
commercial Digital One network, so it is unlikely that D1 will be
able to attain the almost universal (98%) coverage that would seem to
be the aim of the BBC. Due
to the laws of dimishing returns; further expensive transmitters would
cover increasingly smaller areas of population to a point that, for
DAB, the cost of coverage per head of population becomes economically
unjustifiable.
In 2005 Ofcom released an additional frequency
block in VHF Band III for a further national DAB multiplex. The
licence to operate this second national DAB multiplex was wond by a
Channel Four Television consortium, but by 2009 the economic downturn
had made the business model financially unviable and Channel Four were
forced to hand back the licence, so for the time being there will not
be a second national DAB multiplex.
In 2005 Ofcom also released a further three frequency blocks for
expansion of
local DAB multiplexes to provide almost universal coverage in areas
already served by major commercial local radio stations.
Note that BBC local radio does not have its own multiplex. BBC local
radio stations are carried on the local commercial radio multiplexes by
agreement.
BBC National
Multiplex Coverage Map 2006:
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Above: BBC National
DAB Radio coverage in 2006
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Commercial
National (Digital One / D1) DAB Coverage Map 2009:
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Above: Digital One National DAB
Coverage as in 2009
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Map Showing The
Commercial Local Multiplexes Operating By 2005:
[Note: These
commercial multiplexes are obliged by Ofcom to carry the BBC LOCAL
RADIO
station(s) in their area]
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LOCAL
DAB
MULTIPLEXES LICENCED UP UNTIL 2005
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ADDITIONAL DAB
COVERAGE AREAS
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Apart
from
the coloured areas shown on the map, additional local DAB coverage
is also provided, or will soon be provided in the following areas:
Cornwall, Plymouth, Reading & Basingstoke, Nottingham, East
Sussex, Great Yarmouth, Cardigan Bay,
Montgomery, Colwyn Bay, Carlisle, West Cumbria,
Dumfies & South West Scotland and The Borders.
There
are many "white" areas on the map
where, under the original plan, there were no spare frequencies
available for local
DAB coverage. This situation was resolved in 2005 when the
government
and Ofcom released additional spectrum space in VHF Band III for
further DAB expansion. This comprises three additional frequency
blocks. These 'white'
areas
include Northamptonshire, North Devon, Hereford and Worcester,
Somerset, Gloucestershire, North Norfolk, Suffolk,
Cambridgeshire, Oxfordshire, South West Wales, North Wales,
Lincolnshire, Shropshire, Western Scotland and Northern Ireland
Ofcom have also
allocated an additional VHF Band III frequency block to
provide one extra national
commercial DAB
multiplex.
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NOTE ABOUT LOCAL
MULTIPLEXES NOW ON AIR: In addition to the solid areas marked on
the above map, the following areas have now had their local multiplexes
switched on:
Cornwall 11B - NOW Cornwall; Plymouth 12A - NOW Plymouth;
Reading 12D - NOW Reading & Basingstoke;
Nottingham 12C - NOW Nottingham. All now on air.
Local
multiplexes have also been
authorised for East
Sussex, Great Yarmouth, Cardigan Bay,
Montgomery, Colwyn Bay, Carlisle, West Cumbria,
Dumfies & South West Scotland and The Borders and will subsequently
come
on air after the usual Ofcom advertisement and awards procedures.
The map above
shows the licencing structure up to 2005 and takes advantage of all
the spectrum space
(frequencies) that had been made available by the government / Ofcom in
V.H.F.
Band III for DAB radio at that time. Three additional
frequency blocks approved by the government / Ofcom in 2005 in
the V.H.F. Band III will allow more local services (multiplexes) to be
added, and thereby filling in many of the "white areas" that until then
had been left with no prospect of a local DAB multiplex - which
carry both local commercial stations and the BBC Local Radio station(s)
in the area:
Ofcom has begun
licencing the additional local multiplexes from 2006 onwards.
This will provide virtually
universal coverage of local DAB broadcasting.
The 'white'
areas
that include Northamptonshire, North Devon, Hereford and Worcester,
Somerset, Gloucestershire, North Norfolk, Suffolk,
Cambridgeshire, Oxfordshire, South West Wales, North Wales,
Lincolnshire, Shropshire, Western Scotland and Northern Ireland
Ofcom have also allocated an additional VHF Band III frequency block to
provide one extra national commercial DAB
multiplex that may have similar coverage to the existing commercial
national multiplex operator, Digital One.
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| Click to view DAB
DIGITAL RADIO PAGE |
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Above: Digital One
National DAB Coverage as in 2006
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