No. 31 TRANSMISSION, TECHNICAL STANDARDS AND RESEARCH
Transmission
Before the Broadcasting Act 1990, the Independent Broadcasting Authority (IBA), the ITC’s predecessor, was responsible for the transmission of television and radio for the ITV and commercial radio companies, Channel 4 and S4C in Wales. As a result of the Act, the bulk of the IBA’s engineering and transmission division was established as a separate company, National Transcommunications Ltd (NTL). In 1996, NTL was bought by CableTel, which has now adopted the name ntl.
In 1997 the former BBC television and radio transmission operation was privatised and became (apart from the World Service transmission aspects) Castle Transmission International, now known as Crown Castle International.
Broadcast transmission is licensed under the Telecommunications Act 1984, and economic regulation is carried out by Oftel. The ITC regulates the technical quality of television transmission through its licensing of Channels 3, 4 and 5 and digital terrestrial multiplex services.
The Broadcasting Act 1996 gives powers to the ITC in relation to transmission standards, with particular emphasis on digital services. See ITC note 40 for more information on digital TV and ITC note 45 for more information on conditional access.
Spectrum Management
The radio frequency spectrum available for television broadcasting is a limited and valuable resource. The ITC has a responsibility to ensure that the broadcast bands are put to good use. The majority of the ITC’s frequency planning work is carried out under subcontract by ntl or by Crown Castle Ltd. Overall, the ITC has to ensure that effective use is made of the radio frequency spectrum in the planning of new services and extensions to existing services.
Channel 3 (ITV) and Channel 4 services (including S4C in Wales) cover over 99% of the population of the UK, while Channel 5 is available to 80% of the UK population.
The ITC was responsible for preparing the frequency plan for the transmission of the Channel 5 service, and was involved in planning coverage extensions which provided improvements to the original plan. However, there is little scope for further extensions to Channel 5's analogue network, due to a shortage of available transmission frequencies, and it was always recognised that the service would not be able to match the coverage achieved by the main four analogue networks.
Digital terrestrial television (DTT) brings about a significant improvement in spectrum efficiency in the long term. The ITC prepared (in co-operation with the BBC) the frequency plan for the six UK DTT multiplexes, and is actively involved in the frequency planning which is necessary for the long-term transition to all-digital broadcasting in the terrestrial UHF bands. The ITC is leading the work of the Spectrum Planning Group as part of the government Digital Television Action Plan.
The ITC also manages frequency planning for Restricted Services Licensing (RSL) television services that provide locally oriented programming or coverage of events, in areas where frequencies are available.
Technical Quality Regulation
The Broadcasting Acts (1990 and 1996) require the ITC to include conditions in its licences for Channels 3, 4 and 5 and for multiplex services, which require the signals carrying these services to attain high standards of technical quality and reliability, throughout so much of the service coverage area as is for the time being is reasonably practicable.
These conditions require observance of the ITC Technical Performance Code. The main responsibility lies with the licensee to ensure that the material that it broadcasts is of the required standard. Compliance is verified by monitoring licensees’ own procedures, and assessing trends in performance. In view of the important role of public service broadcasters, particular attention is given to trends in standards of quality delivered by the relevant licensees. In addition, trends in complaints received via the ITC Viewer Relations Unit or via the ITC’s Regional Offices which refer to technical quality and reliability are considered against the requirements of the Code.
Standardisation
The development of new broadcast technology will bring benefits to viewers in the years ahead. Before affordable new systems can be introduced to consumers, however, a high level of investment will be required by manufacturers and broadcasters. One way in which the confidence to make this investment can be gained is through the agreement of international standards.
The ITC liaises with industry and standards groups to facilitate the development and adoption of open technical standards for the reception of its licensed public service broadcasts, in order to improve the interoperability of new consumer products.
As the regulatory body for commercial television, the ITC is able to provide the focus for long-term broadcasting developments and to advise the Government on the representation of UK policy on these matters both within Europe and in the rest of the world.
The ITC participates in the work of the standards committees of the European Broadcasting Union (EBU), the European Telecommunications Institute (ETSI), the International Telecommunications Union (ITU), as well as several other national and international industry and standards bodies.
Development of New Technology
New media technology developments mean that new types of video service are emerging and evolving. These might be delivered over satellite, cable, and mobile and fixed telecommunications systems. New types of interactivity are also emerging. Viewers can feed back responses, request further information, buy goods or services, or influence the way a programme evolves. The ITC needs to track and understand these technology developments to ensure that the regulatory framework and practice remain appropriate.
The ITC is also actively involved in the development and application of new technology for television. New systems are under investigation that would enable the implementation of copyright protection for programmes broadcast on television, and also content signalling and labelling. Of particular interest is the study of options for the future release of UHF spectrum, and the uses to which released spectrum might be put, arising from the eventual switchover from analogue to digital broadcasting.
We especially focus on technology where it can improve the accessibility of television by all citizens. For example, the ITC is currently leading a DTI funded project VISTA, that aims to develop a talking Electronic Programme Guide system to allow visually impaired viewers to select more easily the programmes they want to watch on digital television. We are also investigating the feasibility of using special processing in a digital television receiver to suppress background programme sounds to make the programme dialogue easier to understand for viewers with some hearing loss.
The ITC is also actively involved in promoting with its partners the Consumers Association and the Design Council, the need for easier to use digital television equipment that will ensure that all consumers are able to access and benefit from the expanding range of services available on digital television.
Further References
ITC Publications
ITC technical performance code (October 2000)
Television transmitting stations in the UK.
Technical enquiries are dealt with by technology specialists who may be contacted via the ITC Viewer Relations Unit, Tel: 0845 601 3608.
Enquiries relating to operational matters such as transmitter fault conditions, abnormal working and maintenance affecting television reception are the responsibility of the programme company concerned.
April 2003
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