Elena Puigrefagut (EBU)
While Europe seems divided on which position to take at the World Radiocommunication Conference in Dubai in November (WRC-23), the Radio Spectrum Policy Group (RSPG) of the European Union has prepared a draft opinion on the use of the 470–694 MHz band beyond 2030. After an open consultation during the summer, the draft opinion is expected to be approved in October.
The 470–694 MHz band is the core band for digital terrestrial television (DTT) and audio PMSE (e.g., radio microphones). It is governed by the ITU Geneva 2006 Agreement (GE06). However, the extent to which the band is used by broadcasting services differs across countries.
At EU level, the band is made available to broadcasting services, including free television and audio PMSE, until at least 2030. This was a provision of the same EU Decision (2017/899) that harmonized the use of the 700 MHz band (694–790 MHz) for mobile services (5G mobile) across the EU after a common date (30 June 2020) and called on the European Commission to review the use of the band. Although the Decision does not include a date for such a review, the so-called Lamy Report, which formed the basis of the Decision, points to 2025.
In advance of any regulatory decisions that WRC-23 may take and the EC review of the use of the band by 2025, the RSPG draft opinion analyses the flexibility in the existing regulation, discusses different future usage scenarios, and provides recommendations to Member States.
The RSPG recognizes that the existing regulation already provides enough flexibility for the use of the band by services other than broadcasting, for example mobile services, in function of national needs. This flexibility is found:
- in the Decision (EU)2017/899, although any new use needs to respect the interference requirements of broadcasting services in neighbouring countries and cannot claim protection from them;
- in the GE06 Agreement via the envelope concept, which relies on the equivalence of spectral power density to allow the use of a frequency assigned for DVB-T by another service of equivalent spectral power density. Declaration 42, signed by all EU Member States, extends the concept to any type of service irrespective of whether or not it has a primary status in the table of frequency allocations of the ITU.
This recognition of existing flexibility in current regulations is important because those countries supporting a co-primary allocation of the 470–694 MHz band to mobile services at WRC-23 claim ‘flexibility’ as one of the main arguments. Broadcasters have always said that the regulations are already sufficiently flexible and that co-primary allocation would not bring any additional flexibility. On the contrary, various studies and real cases have shown that broadcasting and mobile services cannot operate on the same frequencies in the same or adjacent areas without causing harmful interference to each other. The interference can be reduced by geographically separating the services with large distances, which could go, in some cases, up to several hundred kilometres. Therefore, such an implementation would be impractical in many European countries.
The RSPG draft opinion also recognizes that Member States have not made use of the existing regulatory flexibility, apart from some local trials with new services as 5G Broadcast. However, the opinion does not mention that the 5G Broadcast standard has recently been updated to include 6, 7 and 8 MHz bandwidths, therefore being able to use the full potential of GE06 digital entries, which are harmonized at 8 MHz.
5G Broadcast is to be deployed using existing high-tower, high-power broadcasting sites, currently used for DTT. By choosing modulation parameters that deliver a robust 5G Broadcast signal, good coverage for mobile reception can be achieved without the need to deploy dense low-power networks. Therefore, the introduction of 5G Broadcast alongside DTT would not significantly increase the adjacent channel interference levels, contrary to what the RSPG draft opinion says.
Possible future scenarios
Three possible future use scenarios in different EU Member States are discussed in the draft RSPG opinion. The first scenario assumes DTT as the main platform in the 470–694 MHz, to deliver linear television content for at least the 2030–2040 period in a given country. Non-linear content would be provided via broadband platforms and the platforms could be combined through the use of technologies like HbbTV and DVB-I. PMSE would continue using the band and innovation would be possible through deployment of the most efficient technologies (such as DVB-T2 and HEVC video coding).
The second scenario considers that DTT could still be the main platform for linear television but that part of the band could be used for 5G Broadcast and/or mobile services limited to downlink only (using SDL, supplementary downlink). That scenario assumes that both 5G Broadcast and SDL could use existing GE06 coordinated frequencies as well as, potentially, interleaved spectrum, reducing additional coordination efforts.
This raises some concerns. SDL is a mobile service that would be deployed by mobile network operators using dense low- power networks. Coexistence with DTT and 5G Broadcast, both using high-power, high-tower sites, would be difficult in terms of adjacent channel interference. This type of interference between broadcast services can be mitigated by co-siting the services. Co-siting broadcasting and mobile services like SDL seems difficult and even impossible when we talk about different types of networks. Adding filters to roof-top antennas is another mitigation option in cases of fixed broadcast reception but it would be impractical in the case of SDL using interleaved frequencies.
The third scenario assumes that the use of the band by DTT in some countries would be limited and that mobile services would implement a full FDD (frequency-division duplexing) band plan with both uplink and downlink streams. This scenario is of high concern for broadcasters because the implementation of mobile uplink services would require significant and probably challenging frequency coordination efforts and PMSE would have a reduced range of frequencies to access.
The RSPG draft opinion provides ten final recommendations. They are broadly aligned with broadcasters’ views. A few are worth highlighting here.
The diversity of situations across EU countries regarding television viewing habits makes it impossible to harmonize a single scenario for Europe for the use of the 470–694 MHz band, even after 2030. Member States can use the flexibility in existing regulatory measures to implement different uses and future regulatory measures will need to take account of the diversity of scenarios.
Technical coexistence of the different scenarios is difficult, and solving interference issues requires detailed and complex cross-border coordination between countries. In particular, the RSPG notes that a harmonized FDD plan for the 600 MHz band throughout the EU is not anticipated, and certainly not up to 2030.
In addition to the technical evolution of television services, there are other important nation-specific factors such as market demand, audiovisual policy and sovereignty, which will be crucial in the coming years in shaping the use of the 470–694 MHz band after 2030.
In the meantime, WRC-23 in November will take decisions regarding the spectrum allocations in the UHF band. While both the broadcaster (AUB) and telecommunications (ATU) bodies in Africa and the countries of the Regional Commonwealth for Communications (RCC) have already agreed a position of No Change’ in line with the EBU, Europe still needs to confirm its position, hopefully aligned with RSPG recommendations that support the use of the band for DTT and PMSE.
This article first appeared in issue 57 of EBU tech-i magazine.
- For further information on the EBU’s position regarding WRC-23, see the white paper No change at WRC-23 maximizes public value and innovation in the UHF band.
- EBU Technical Report TR 064 explores compatibility between 5G Broadcast and other DTT systems in the sub-700 MHz band.