No. 290 (April 2002)
This issue of the Technical Review contains three articles on international planning conferences. Terrestrial broadcasting in Europe today is determined to a large extent by the 1961 Stockholm Plan for the VHF/UHF bands. Although broadcasting has developed greatly since 1961, the Stockholm Plan is still very important. It made assignments for many of today's FM radio and TV broadcasting services – and set criteria for addition of new services without causing undue interference to existing services. Few of those involved in the 1961 Conference would have expected that their work would still be valuable 40 years later.
Part of the Stockholm Plan was revised at a Conference held in Geneva in 1984. This covered use of the VHF Band II for FM sound broadcasting, particularly its extension to 108 MHz. Similarly, the Wiesbaden DAB planning conference in 1995 and the Chester Agreement in 1997 on digital terrestrial TV planning enabled the introduction of digital broadcasting. In June 2002, a conference will be held in Maastricht to plan the use of terrestrial DAB services in the 1.5 GHz band.
Despite all of this activity, full-scale digital broadcasting requires major re-planning of broadcasting networks. Consequently, the ITU has decided to convene a planning conference to revise the Stockholm Plan: a preparatory technical session will be held in May 2004, followed by the planning sessions in 2005 or 2006.
The first challenge is to find ways of permitting digital broadcasting to operate side-by-side with analogue broadcasting – without causing mutual interference whilst allowing the digital services to achieve significant coverage. As "radio waves do not respect national boundaries", this problem becomes even more complicated. In all European countries (with the notable exception of Iceland), broadcasting use of the spectrum is severely constrained by the need to avoid interference to or from services in adjacent countries. Although each country could have bilateral negotiations with each of its adjacent countries, it is more sensible for all countries to agree on some planning principles. This usually involves an international planning conference organized by the ITU or CEPT. As described in the various articles, such conferences may start with high ideals, but end in a series of compromises!
The second challenge is to determine how the spectrum can be used most efficiently in an all-digital era (i.e. when analogue broadcasting has been withdrawn). It seems unlikely that the optimal solution for the mixed analogue and digital environment will be optimal for the all-digital environment.
Even worse, the revised plan must accommodate the dramatically different requirements of different countries: for example, some countries envisage a rapid transition from analogue to digital broadcasting but their neighbouring countries want a more relaxed timetable. Some countries want digital TV services targeted at mobile and portable TV receivers, whereas others are planning on the basis of "traditional" TV services delivered via roof-top antennas.
Each EBU Member must decide if it needs digital terrestrial broadcasting (radio or TV). Some may feel there is no urgent need to introduce digital broadcasting within, say, the next 5 years. However, most recognize that digital broadcasting is inevitable in the longer term – partly because digital broadcasting offers many benefits and partly because analogue broadcasts may have to be closed down. If they want to introduce digital broadcasting, they will need adequate spectrum for digital broadcasting. This means that they must persuade their national administrations and/or spectrum regulators to participate actively in the forthcoming conferences.
A further challenge is that some other users of the spectrum (e.g. mobile telephone companies) are very keen to obtain access to the spectrum currently used for TV broadcasting. Governments and spectrum regulators are hoping that the revision of the Stockholm Plan will allow them to reallocate some spectrum currently used by broadcasting to other users. Given the planning problems caused by the coexistence of analogue and digital broadcasting, most broadcasting experts feel that little spectrum will be available for reallocation. But that view may not shared by spectrum regulators – or by telecoms operators!
In early March 2002, the UK Government published a "Review of Radio Spectrum Management" by Professor Martin Cave, who is a highly respected economist. This report emphasizes the need for flexibility in spectrum allocations and suggests that this would be best achieved by allowing market forces to determine the best use of the radio spectrum. Professor Cave proposes that "spectrum trading" should become the norm: all spectrum users would be required to pay charges that reflect the market value of "their" spectrum, but they would also be allowed to sell or lease any unused spectrum to other users.
The principle of spectrum trading is that it provides an incentive for existing users to release their spectrum to other users, especially to users who would pay the most for access to the spectrum. By such means, the hope is that spectrum usage would migrate over a period of time from "low value" to "higher value" applications. This implies an end to traditional methods of spectrum allocation. At present, the ITU Radio Regulations include frequency tables which allocate frequency bands to specific services, such as aeronautical mobile, broadcasting, fixed-satellite, radionavigation, radioastronomy, etc. If spectrum trading becomes a reality, we will not need international planning conferences!
Such concepts are undoubtedly attractive to Governments (who are concerned with improving the economic climate) and to spectrum regulators (who face the almost impossible task of finding spectrum for new users whilst protecting the services of existing users). However, in most cases, it is difficult to identify the market price for spectrum. Professor Cave's view is that auctions should "become the default means of assigning licences to exclusive frequency bands". In a previous editorial entitled "Spectrum pricing", I outlined some of the problems of spectrum auctions as a mechanism to find the market price of spectrum.
Furthermore, Professor Cave recommends that broadcasters should pay the full market rate for their use of the spectrum. As public service broadcasters are obliged to provide near universal coverage (e.g. all EBU Members are required to provide services covering 98% of their nation's population), it can be argued that they have little discretion in how they use the spectrum. In many countries it would be possible to cover 70% of the population with just a few transmitters (and frequencies) – but providing coverage to 98% or more of the population requires much more spectrum. Unfortunately, Professor Cave rejects such arguments and insists that "spectrum charges on these broadcasters are justified".
Many EBU Members might think that the ongoing debates in the UK do not concern them. However, Professor Cave's report is likely to be influential beyond the UK. In particular, his view is that spectrum trading should be applied across Europe. As it is already very difficult to co-ordinate spectrum usage on an international basis – even where adjacent countries use spectrum for the same purpose (e.g. broadcasting) – it is obvious that spectrum trading faces huge problems, especially in the areas near to national borders.
In this respect, UK thinking may be conditioned by the fact the UK is physically isolated from the rest of Europe. This means that the UK has greater freedom in how it uses the spectrum compared with most countries in Europe that share land borders with several other countries. However, the UK's regulators seem to have forgotten a "bad experience": in the early 1980s, the mobile radio operators in the UK were desperate for additional radio spectrum and demanded access to the VHF "broadcasting" bands. They were not really very interested in Band I, but they declared VHF Band III to be "prime spectrum for mobile radio". The UK Government accepted their arguments, deciding that broadcasting in VHF Bands I and III should cease at the beginning of 1984 and that the released spectrum should be allocated to land mobile radio services. It is instructive to examine today's use of VHF Band III in the UK. Despite the increasing demands for spectrum for mobile radio services, VHF Band III is, even today, barely used for mobile radio. Why?
With the benefit of hindsight, we can see that the UK spectrum regulators underestimated the difficulty of using this spectrum for mobile radio whilst other nearby countries, such as France, Belgium, Netherlands and Ireland, continued to use it for TV broadcasting. Initially, it was felt that low power (25 watt) mobile radio transmitters could easily be accommodated in Band III. It was recognized that there might be a problem of occasional interference from TV transmitters in, say, Northern France to mobile radio services in London. In fact, the real problem was interference from mobile radio transmitters to TV services: the wide bandwidth of TV transmissions makes them susceptible to interference from mobile radio transmitters using many narrow-band (e.g. 12.5 kHz) channels. As the cumulative effect of such interference can be very significant, the spectrum regulators and broadcasters in adjacent countries rightly demanded that their TV services should be fully protected against interference. As mobile radio became subject to severe constraints, such as power limitations and regional restrictions, VHF Band III failed to become a valuable resource for mobile radio in the UK.
This "history" lesson indicates that radio services cannot be planned in isolation from neighbouring countries. Spectrum trading may offer many benefits, but we need to be realistic about the prospects for practical implementation. Spectrum trading certainly cannot ignore the problem of protecting other users, especially those in adjacent countries.
Innovative ideas, such as spectrum trading, must not divert our attention away from the forthcoming international planning conferences. Some EBU Members, together with the EBU Technical Department, are already making preparations for the 2004 and 2005/2006 Conferences. Although 2004 may seem to be very distant, there is a huge amount of technical work to be done if broadcasters are to obtain a satisfactory result. All EBU Members must ensure that they have the appropriate planning expertise and can devote sustained effort over the next 4 years to these important events.
Philip Laven
Director
EBU Technical Department
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