Memorandum submitted by Parliamentary
Office of Science and Technology (POST)
DIGITAL CONVERGENCE AND THE BBC CHARTER
INTRODUCTION
The BBC's Royal Charter is due for renewal
in December 2006. The Culture Media and Sport (CMS) Select Committee
announced an inquiry into the Charter renewal in March 2004. This
report is to provide the CMS Committee with an idea of how the
relevant technology has developed since POST examined the development
and convergence of digital communications in the UK in 2001 (POST
report and POSTnote 170[24]),
where the technology may take us over the time-frame of the next
Charter, and what the implications are for public service broadcasting.
BACKGROUND
Rapid changes in communication technology
are affecting the world of broadcasting. Whereas, until six years
ago, all television (TV) channels in the UK were received in analogue
form, many television programmes are now encoded and delivered
using digital technology. By encoding the signal digitally more
services can be delivered over a given amount of spectrum so enabling
more choice of channels as well as a range of interactive services.
Digital television
Digital TV (see below) in the UK can currently
be accessed by three main methods:
— digital satellite, mainly provided
in the UK by BSkyB;
— digital terrestrial television (DTT)
delivered through TV aerials, provided by the Public Service Broadcasters
and others, including Freeview (a consortium of the BBC, Crown
Castle International and BSkyB) and a (recently-launched) "pay-light"
subscription service provided by Top Up TV; and
— digital cable, via companies such
as NTL or Telewest.
Traditional analogue televisions cannot
decode digital signals, so viewers need either a set-top-box to
convert the signal or an integrated digital TV set (iDTV). Currently,
set-top-boxes for converting digital terrestrial TV (DTT) signals,
including Freeview, can cost under £50. Top Up TV requires
a slightly more complicated set-top-box or iDTV set, with the
PayTV facility either built-in or plugged in to a special "CI"
socket. For satellite TV, installation of a receiver dish and
satellite decoder is necessary. Most channels are received by
subscription or pay-per-view, but some can be received freely
(notably the BBC channels). Cable reception is also by subscription
and pay-per-view.
Digital television is more efficient in
its use of radio spectrum than analogue TV. Switching off analogue
TV will release some of the spectrum for further digital TV services
or other communication uses. In September 1999, the Government
set two pre-conditions for switch-off:
— availability—everyone who can
currently receive the main public service broadcasting channels
on analogue television (99.4% of the population[25])
must be able to receive them digitally by one or more methods;
and
— affordability—as an indicator
of this, 95% of consumers must have a digital TV receiver in the
home.
What is digital TV?
Until 1998, all TV channels in the UK were
received in analogue form—a continuously variable signal—whether
by aerial, satellite dish or cable. Digital TV encodes the original
television picture as a series of numbers (1s and 0s) then uses
computer processing to compress it so it can be transmitted in
a fraction of the "space" in the radio spectrum taken
by the equivalent analogue TV signal. Advantages of this method
of encoding and transmission include:
— more services can be delivered over
the same radio-frequency channel—so a wider selection of
services is possible;
— many different types of digitised
information can be transmitted—such as sound, still or moving
pictures, text and data. For example, as well as traditional programming,
faster, more interactive and graphical teletext services are possible;
— the digitised signals can be readily
manipulated using computer technology, stored electronically and
adapted for presentation on different devices;
— it is easy to provide interactive
services, such as using the remote control to obtain more information
about programmes, or with a modem and phone line to provide full
two-way interactivity (see Interactive section); and
— because a digital TV service takes
up less spectrum than its analogue equivalent, switching over
completely to DTT will make it possible to release some of the
UHF spectrum (see Spectrum Management section) for other purposes
(such as navigation or other communications). The Government argues
that this re-use will have economic benefit. However, much of
the released spectrum could still be used for digital TV or increase
the number and/or technical quality of services available. Further,
only limited spectrum could be re-allocated without requiring
large groups of viewers to change their receiving aerials.
Spectrum management
Both analogue and digital TV and radio
signals are transmitted over air in the radio frequency bands
of the electromagnetic spectrum. Both analogue TV and DTT share
the same (UHF) band.
DTT services are currently broadcast over
six multiplexes, or data pipes. Each multiplex carries several
channels and can be easily reconfigured to vary the number of
channels carried. However, this number is reduced when programmes
are transmitted at higher quality or resolution as this takes
up more bandwidth. New technologies have been developed which
are better at compressing the digital TV signal. These could,
in theory, increase the efficient use of the DTT bandwidth, but
would require all the existing DTT transmission systems to be
modified as well as a complete replacement of the existing receiver
population. However, these new technologies may be used in the
future to squeeze a broadcast quality TV signal down an xDSL telephone
line (see Broadband section).
Analogue-digital switchover
In 1999 the Government stated that digital
switchover could start in 2006 and be completed by 2010. To achieve
this completion date a Government decision to proceed on this
basis would need to be made around the end of 2004. The Government
will need to work closely with the communications regulator (Ofcom),
manufacturers, broadcasters and retailers to achieve this date.
The speed of digital technology development
soon makes the current generation of devices out of date. Consumers
are used to renewing computers and mobile telephones fairly regularly
to keep up with the latest applications, but they are not so used
to regularly changing their television sets and video recorders.
An upgrade policy is therefore needed to help encourage people
to keep up with the digital TV world. The technology is also very
complex, but needs to be extremely simple to install and use to
encourage widespread uptake.
Fifty-three per cent[26]
of households now have digital TV, up from 50% at the end of 2003
and 41% at the end of 2002. All the distribution platforms (methods)
are important to ensure widespread access to digital TV, taking
into account affordability and geographical coverage:
UK viewers by television distribution
platform (primary TV set) at end 2003
Sources: Ofcom, BBC estimates
of Freeview take-up (primary TV set only) and free-to-view satellite.
Does not separately show the very small numbers of subscribers
who receive linear digital TV channels via an xDSL service.
— DTT—the introduction of Freeview
in 2002 rapidly increased the uptake of DTT, with affordable decoders
and a wider choice of free-to-view channels than analogue TV.
During 2003 1.5 million DTT set-top-boxes or iDTVs were bought
and sales of iDTVs doubled.
— Digital satellite—subscribers
to SkyDigital have also continued to increase with 600,000 homes
added, during 2003, to the 6.9 million that already pay monthly
subscriptions for their pay TV services. Although there is almost
full geographical coverage (98%) by satellite there are some areas
that are in a satellite shadow or some buildings which cannot
have a satellite dish, eg for environmental reasons.
— Digital cable—the number of
homes with cable TV stayed constant throughout 2003, maybe because
they have not had any further major roll outs for financial reasons.
— Broadband—Digital Subscriber
Line (xDSL) technology (broadband) is forecast to start taking-off
as a platform for digital TV distribution this year with broadband
subscribers increasing rapidly (see Broadband section).
The terrestrial analogue signal will be
turned off region by region. Individual analogue channels may
also be turned off in sequence to free up some of the spectrum
for replacement high power digital transmissions before the final
total analogue switch-off date. It has not yet been decided in
which order the channels will be turned off.
It has been forecast that, left entirely
to the market, digital TV will be in 95% of households by 2013[27],
with only 72% of first TV sets converted by 2010[28].
Therefore, there are several barriers that still need to be overcome
before analogue switch-off if a 2010 date is to be achieved. These
include:
— Communication and marketing—a
report by the Generics Group for the Digital Television Project
shows that many people are not fully aware of what digital switchover
will mean. It is thought that when a definite date is announced
for analogue switch-off this will make a difference to the rate
in which people convert to digital TV. 5% of respondents to the
survey said they would never convert, with cost being reported
as a significant barrier. The report recommends that this barrier
be addressed, as well as encouraging people to start converting
to digital now so there is not a surge in demand for digital equipment
just before switchover in each region. However, there are still
millions of consumers who see no reason to adopt digital TV at
all, because they see the analogue switch-off policy as coercive;
think the new technology is too expensive, confusing and difficult
to use; or are simply happy with what they have already.
— Converting secondary TV sets—many
households that have digital TV have only their primary sets converted.
41% of viewing in all homes is on secondary sets, and only 14%
of these have been converted so far.
— Aerial problems—some households
need new roof-top aerials, either to increase the signal strength
or to have a wideband reception to receive all DTT channels. This
problem will probably still exist after switchover. Some roof-top
aerials will have to be adjusted or replaced to receive signals
from a different transmitter. Many secondary sets use set-top
aerials through which it will be challenging to ensure good reception.
— Recording method—recording
digital broadcasts on video cassette recorders (VCRs) is not easy
at the moment. Using a (single tuner) set-top box for both the
TV and VCR will not allow viewers to watch one digital channel
whilst recording another digital channel. Twin-tuner set-top-boxes
could provide a solution. There are Personal Video Recorders (PVRs—see
Time-shifting TV section) with twin DTT tuners on the market already
but many viewers will want to retain their VCRs.
— DTT coverage—currently only
73 % of UK households can receive the full DTT service. Even after
analogue services have been withdrawn, and DTT transmission powers
increased, only 95% of households would be reliably covered from
the 80 current transmitter sites.
— Free-Sat—as DTT is not currently
receivable by the whole country, a viewer-friendly solution is
needed to provide a reliable subscription-free way of receiving
the main public service broadcasting channels via digital satellite.
Ofcom's role in switchover
Ofcom is the new communications regulator.
It replaced the five previous regulators at the end of 2003. Ofcom
is carrying forward the previous regulators' work in the sphere
of spectrum planning. This will include:
— considering spectrum charging, including
to the BBC who are not charged at the moment, to ensure efficient
use of the spectrum[29].
Increased charges for access to the existing analogue TV broadcast
spectrum might also act as a significant spur to the broadcasters
to promote early switchover;
— negotiating, planning and evaluating
the use of any released spectrum and co-ordinating the plan for
the regional roll-out of digital DTT transmission;
— reviewing the role and delivery of
public service broadcasting in an all-digital world;
— assessing the ease of use of digital
TV equipment on sale and enhancing the public's media literacy;
and
— monitoring and analysing the broadcasting
market and digital TV adoption and monitoring competition in the
broadcasting market.
THE CHANGING
FACE OF
BROADCASTING
Broadcasting is no longer simply scheduled
television on TV sets and radio programmes on radios. The BBC
already has an extensive, continuously developing website that
is widely used throughout the world. It is also possible to listen
to a number of BBC and commercial radio services on digital televisions,
to see written information and images on digital radios (see below),
to watch television on PCs and to watch videos and listen to the
radio on the Internet. There are several key trends in digital
technology:
— increased local storage (up to 4,000
hours of video by 2016);
— increased bandwidth to the home (enabling
films to be downloaded in minutes by 2016);
— increased personalisation (to help
make sense of huge increase in choice); and
— increased interactivity (enabling
new forms of virtual community).
Production
Most TV programmes are now produced using
digital technology because it is efficient and economic to do
so. It is also easier to store and re-use material. Programmes
can be made at a very high quality, if they are deemed to have
a long commercial shelf life. Once a programme is made at high
quality it can be distributed at a lower quality if necessary.
In preparation for a wider use of digital
technology, the BBC and others are already making high definition
television (HDTV) programmes even though there is only one HDTV
satellite service in Europe at the moment, serving Belgium (see
below). Some of these programmes can be sold to the USA that can
broadcast them on HDTV sets now. They can be broadcast in the
UK when this technology is ready to be used and enough people
have the appropriate sets for there to be a sufficient market.
High Definition TV
High Definition TV (HDTV) has a very high
picture quality, which is especially needed on larger screens
and for viewers used to DVD-video quality. Technological developments
and market circumstances mean that HDTV could be broadcast in
the UK within the next five years. However, it would be extremely
bandwidth-hungry, requiring most of a DTT multiplex which could
otherwise carry four to six Standard Definition [SD] channels.
Limited DTT bandwidth suggests that, in the absence of improvements
in the compression technology currently implemented for European
digital TV, HDTV could only be efficiently introduced for the
satellite and cable platforms. Although production costs for HD
programmes are similar to SD, there is a limited amount of suitable
content, eg high-end drama and sporting events such as the Olympics.
In addition HDTV is not compatible with any of the current digital
receivers and so a new specific HD receiver or TV would need to
be purchased by consumers.
The BBC, which is considering distribution of
HD, suggests that broadcasters could go a long way towards improving
picture quality, without making the leap to HD, by paying closer
attention to the way SD services are made and transmitted. Distribution
of HD would not, in itself, be a driver for digital take-up for
the owners of millions of small-screen SD analogue televisions
currently in the market, but it would be a service potentially
of interest to the growing number of owners of large screen devices.
Broadband
Broadband could become a fourth main method
for delivering digital TV once it is more widely available. Broadband
is a term used to refer to a group of technologies that can deliver
content to users over high speed telecommunications networks eg
cable or xDSL (a technology that allows copper telephone lines
to transmit broader bandwidth). This access is always available,
without the need to dial up.
Growth in UK broadband connections by residential
users and SMEs[30]
at the end of April 2004
Source: The Ofcom Internet
and Broadband Update. Ofcom, April 2004
Broadband roll-out is accelerating with
a 200% increase in take-up between October 2002 and November 2003.
There are now more than 3.99 million subscribers to broadband
and it is in 14% of UK homes. Broadband is currently available
to 90% of households, mostly concentrated in urban areas. BT expect
availability to reach 99.6% [31]
of households by the summer of 2005, though the transmission speed
may not always be adequate for full broadcast quality TV across
all of these households.
International broadband Internet take-up,
June 2003
Source: Broadband Audio-Visual
Services: Market Developments In OECD Countries, OECD, January
2004. G7 nations marked with*
With the rise in the use of broadband,
the potential advantages become clearer. It can deliver digital
TV to households where traditional digital TV platforms may be
unattractive, unavailable or impractical. Linear (ie real-time—as
broadcast) digital TV channels are already offered to TV sets
by Kingston Interactive Television and Video Networks (Home Choice).
Also, some PCs can be equipped to receive linear digital TV channels,
such as Sony Vaio, with the added advantage that the PC hard disc
drive can act as a video recorder and time-shift programmes (see
below).
Time-shifting TV
Time-shifting TV allows the viewer to set
their own schedule. One way of achieving this is through video-on
demand, which is now a practical proposition because of faster
broadband access. Video Networks' Home Choice package includes
high speed internet access of 1Mbps[32]
to a PC and digital television and on-demand channels to a television
set, through the same telephone line. The BBC has a video and
audio broadband service and also intends to make their archives
available via broadband Internet; however, programmes with commercial
value will be encrypted to limit access to seven days.
Personal Video Recorders (PVRs), such as Sky+
and similar DTT devices, are another way of time shifting digital
TV. Rather than recording programmes onto a tape, they use a large
hard disk drive (up to about 40 hours). Such systems differ from
conventional video recorders (VCRs) in that:
— as well as recording and playing
back programmes, the device can "pause" live programmes
(by recording the parts transmitted after the pause);
— there is no need to fast forward
or rewind tapes to search for programmes—a digital index
of recorded programmes is maintained and can be shown on the TV
screen;
— viewers can watch one recorded programme
while recording another; and
— some can also learn viewers' tastes
and record suitable programmes without being requested.
Such innovations have a number of possible
commercial and social implications. In some cases the recorder
is plugged into a phone line and calls back to the service provider
every day to maintain up-to-date schedule information. Data about
people's viewing habits could also be transmitted, and because
the hard disc drive is able to record details of all programmes
watched, this raises privacy concerns. Should PVRs become widely
used, the ability to skip advertisements may have ramifications
for advertisers and commercial television channels, although broadcasters
hope to increase the success of advertising spots by adding interactive
content. PVRs are much easier to use than conventional recorders,
which are infamous for the difficulty involved in programming
them. Therefore, it is conceivable that these tools will be used
more widely, allowing people essentially to schedule their own
programming. This could have implications for regulatory structures
such as the 9 o'clock watershed. A wide uptake of these PVRs could
lead to broadcasters transmitting more programmes at off-peak
times specifically to be recorded, so making fuller use of the
spectrum.
Interactive
All UK digital TV operators offer some
TV-specific interactive services, such as an up-to-the-minute
choice of news stories. Web TV, Internet access on the television,
has not taken off, although a few years ago it was thought it
would be very popular; however, its popularity may increase when
accessed over a broadband connection.
There are two levels of interactivity which
can be associated with digital TV. Full interactivity requires
a return telecommunications channel eg a telephone line connected
to the TV or set-top-box to enable activities such as voting.
However many broadcasters make use of "local" interactivity—also
known as enhanced broadcasting—which does not require a
return path. For programmes such as Wimbledon, viewers can choose
which tennis match they want to view and have extra information
such as results, statistics and players' profiles at the touch
of a button without the need for a return path. The level of interactivity
provided by each distribution platform may not always be the same,
even for the same programme, due to the different characteristics
of the platforms; for instance the limited bandwidth on the DTT
platform may restrict what can be provided eg the number of alternative
Wimbledon matches to view.
Electronic Programme Guides
Most set-top boxes and PVRs have electronic
programme guides (EPGs) which enable viewers to:
— see what programmes are available
by date and time—and sometimes by subject;
— view background information, for
example on the actors, directors, the film locations, etc;
— build personal lists of their favourite
channels;
— build personal lists of programmes
to watch in the days ahead—the EPG will then remind them
when the programme is about to start or will start the video/DVD
recorder;
— buy movies on demand; and
— block out specific channels or programmes
above a certain rating.
More advanced set-top boxes and EPGs will
allow personalised profiles to be stored and then used to identify
likely programmes of interest. They will also provide more advanced
search options.
The order that channels are listed on these
EPGs has been shown to influence the watching pattern of many
people. Ofcom is required by the Communications Act 2003 to publish
a Code which would apply to all EPG providers. The Code must explain
how public service channels (the BBC's public services, ITV1,
Channel 4, Five and S4C) should be given "appropriate prominence"
on each television service accessed through an EPG. The draft
Code also sets out what EPG providers should do to enable people
with visual or hearing impairment to benefit from the services
on offer.
Benefits to local communities
Digital technology is allowing services
to target specific communities. The BBC are developing technology
so more television programmes will be signed and/or sub-titled
for the deaf and hard-of-hearing, with these facilities being
an option to turn on. There will also be more audio description
for programmes available for the blind and partially sighted.
Television and radio channels can be more localised. On their
Internet site, the BBC have recently launched a virtual community
interactive website called "iCan". This enables people
to find local information, get involved in local issues and interact
with others in a similar position.
Digital radio
Both analogue and digital radio share the
same (VHF) radio frequency band. As with digital television, digital
radio offers the opportunity for more channels, and high reception
quality. It can also be used to broadcast text and pictures (eg
giving more details on the music being played), and for interactive
services. To receive digital radio, a digital receiver is needed.
The range and affordability of portable digital radios is increasing
but they are still more expensive than analogue radios. It is
also possible to receive several radio services on digital TV,
and many broadcasters also make their output available on the
Internet. There are now many digital stations, with a wide range
of local digital commercial and public service stations. There
are no current plans to turn off the VHF analogue radio signal,
as analogue radio does not use as much bandwidth as analogue TV.
FUTURE DEVELOPMENTS
The spectrum freed by digital switchover
could be used to provide additional broadcasting services such
as extra DTT channels, more radio services and interactive services.
More localised services could be provided. Existing broadcasting
transmitters could be used to send TV and other forms of data
to mobile devices. Provided the necessary international agreements
were secured, the freed spectrum could ultimately supply the capacity
for entirely new wireless communications services, such as mobile
wireless broadband.
Mobility will be an important factor in
future communications. Television could be broadcast to 3G mobile
phones and personal digital assistants (PDAs), which can already
be used to access the Internet, download and play music and videos,
and receive radio. Television could also be available on public
transport, with specially produced, up-to-the-minute short programmes
such as current affairs and news. Freed bandwidth could additionally
be used for management services such as traffic congestion information.
It could also be possible to connect wirelessly all home entertainment
devices, and also control them remotely from a greater distance
using, for instance, a mobile telephone, eg to set the video to
record.
Currently the UK average bandwidth for
broadband is 512 kbps[33],
which costs about £25 per month; higher bandwidths cost more.
However, in Tokyo it is now possible to have 45 Mbps (around 100
times as much) for an equivalent price. 64% of UK households now
have a computer, so with the performance to cost ratio of broadband
doubling every 18 to 24 months then broadband will very quickly
become more and more accessible and commonly used. Current constrictions
on broadband are:
— the cost of laying the fibres to
carry the broadband information and connect with local copper
telephone lines—60% of this is digging up the road;
— the bandwidth bottleneck when the
signal gets closer to the home—the signal needs to go through
the copper telephone lines which slow it up, and there is only
a certain amount of bandwidth which is shared by groups of customers
so high usage in that group slows the data rate;
— copyright and intellectual property
rights challenges, which will become more complicated and more
relevant with the converging technologies; and
— image quality is still not at the
level of traditional television.
It is currently cheaper to broadcast, but with
the advance of broadband, switching may become cheap enough for
consumers to want to set their own schedules more. The effect
that these emerging technologies will have on regulation is currently
uncertain and internet issues are specifically being investigated
within a global context. Internet based audio-visual services
are still not universal enough to replace existing media, but
there is currently a general consensus that broadcast scheduled
television will still have its role in society, even when broadband
is universal.
Summary
Whilst the future of communication technologies
cannot be precisely mapped out, certain general trends can be
projected. The BBC Charter could potentially be renewed for another
10 years, up to 2016. Within this period there will be changes
in the technology used by the BBC and its consumers, and this
will also lead to changes in the way the BBC and its consumers
interact. It could be predicted that in this period in the UK:
— the analogue DTT signal will be switched
off, so all DTT will be digital;
— broadband take-up will become near
universal;
— broadband service will become faster
and better quality with bandwidth being affordable at potentially
100 times greater speed;
— use of broadband mobile devices will
increase, giving consumers access to information on demand;
— video-on-demand and PVRs will allow
greater numbers of consumers to set their own schedules;
— interactive enhanced broadcasting
will be more common, giving more information than the standard
scheduled programmes;
— consumers will use their television
sets for more two-way interaction, eg voting during programmes;
— some information and programmes will
be more localised and community specific;
— consumer choice will increase, so
the interfaces of devices, such as EPGs, will need to be simplified
to increase widespread access;
— it will become much easier for individuals
to create and broadcast their own audio-visual programmes; and
— scheduled broadcast programmes will
still be watched, though will not be as popular as now.
Over the last few years new technology
has already changed the role the BBC plays in public viewing.
In reviewing the BBC Charter and its time frame from 2006, the
Government will have to consider a number of technological issues.
These include:
— for how long will there continue
to be a market for scheduled broadcast programmes?
— with the fragmentation of the broadcast
market, is there still a role for a publicly funded public service
broadcaster?
— how much the BBC should keep up with
changing technologies and how it can do this without affecting
nascent markets?
May 2004
24 E is for Everything? Public policy and converging
digital communications. POST report 170, December 2001. Back
25
Although the figure for Channel 5 is lower. Back
26
Ofcom, May 2004. Back
27
Progress Towards Achieving Digital Switchover-a BBC Report to
the Government, BBC, 26 April 2004. Back
28
Attitudes to Digital Switchover: The Impact of Digital Switchover
on Consumer Adoption of Digital Television. Prepared for the Digital
Television Project by the Generics Group, March 2004. Back
29
The BBC do however contribute to the cost of spectrum enforcement
eg Ofcom's role in shutting down pirate broadcasters. Back
30
SMEs-small and medium enterprises. Back
31
The Ofcom Internet and Broadband Update, April 2004. Back
32
Mbps-Mega (1 million) bits per second. Back
33
10 kbps-kilo (1 thousand) bits per second. Back
|
