The events industry in the UK alone is estimated to be worth GBP 70 billion, with the UK content industry estimated to be worth GBP 43 billion. Both industries are reliant on wireless technologies, for example, to allow speakers and performers to move freely, without the tie of physical cables. The ever-increasing scale and finesse of events require increasingly complex equipment (e.g., wireless microphones and in ear monitors, IEMs) to achieve impressively low latency and high reliability and provide seamless experiences for audiences. These devices are known under the designation PMSE (Programme Making and Special Events) or SAB/SAP (Services Ancillary to Broadcasting, Services Ancillary to Programme-making).
For these devices to function wirelessly however, they require access to spectrum. There are various bands in use by PMSE equipment, but a key band in use globally is the 470-694 MHz range. This spectrum is also used by terrestrial television broadcast services. Broadcast services, generally, make use of high power, high tower networks to provide wide area coverage from relatively few sites. Broadcast transmitters reuse frequencies across the network, but with a separation distance in the tens to hundreds of kilometres to reduce interference. This limits the potential for broadcast services to share the spectrum with many services, but does allow for very effective sharing with PMSE.
PMSE, for the most part, operates at comparatively very low powers, in very localised settings and for limited amounts of time. For example, an event requiring PMSE equipment may only take place within a particular venue, for just a few days. Consequently, PMSE’s spectrum usage is similarly localised and temporary. This allows PMSE to take advantage of the pockets of usable spectrum between broadcast transmissions, so-called ‘white spaces’. Importantly, this sharing arrangement allows PMSE equipment to achieve the low levels of latency and high levels of reliability required in delivering events.
For many years, broadcast and PMSE have been able to share the spectrum incredibly effectively, demonstrating the real opportunity that shared spectrum can offer. The harmonised 470-694 MHz band in use across all of Region 1 allows for easy travel around the Region (broadly EMEA) by PMSE users with equipment able to function well in all territories with comparatively little retuning effort. In many countries, access to this spectrum is also licence-exempt, i.e., users are able to plan usage themselves without having to rely on licences from a central regulator.
Consideration of the band at WRC-23
The 470-694 MHz range is being considered under WRC-23 Agenda Item 1.5 later this year for potential allocation to the mobile service. Consideration of the band is based on the reported decline in the usage of broadcast services in many countries, improvements in the spectral efficiency that broadcast television technologies can achieve, and an increasing demand for mobile broadband services (IMT, International Mobile Telecommunications). Low frequency spectrum is attractive for mobile services in that it propagates well and can achieve superior building penetration when compared with the mid- and high band spectrum used elsewhere in mobile networks. The 700 and 800 MHz bands have previously been refarmed from broadcasting to mobile networks in many countries.
PMSE, like broadcast, has benefited from technological developments that allow for improved spectral efficiency. For example, improved device design and innovations, such as WMAS (wireless multichannel audio systems), can achieve much closer spectral spacing for devices than has been possible previously, effectively reducing the spectrum requirements of PMSE devices. However, whilst demand for broadcast spectrum is reportedly decreasing in some cases, PMSE spectrum is showing the opposite trend. A recent study from the European Commission showed that demand for PMSE spectrum was increasing in 50% of the EU Member States, with Spain showing the biggest increase at 20% a year. As a result, the extent to which technological developments can meet increasing demand, even without any reduction in the available spectrum, is unclear.
Regional positions are still developing ahead of WRC-23. CEPT for example has agreed a European Common Proposal (ECP) to introduce a secondary allocation to the mobile service within the 470-694 MHz band, with the potential to upgrade this to primary at WRC-31, with the current primary broadcast allocation maintained. The ECP also notes the importance of the spectrum for PMSE and expresses support for its continued development. This would arguably be a positive outcome for broadcasting – the primary broadcasting allocation is retained which, any mandated change from national or supranational regulators aside, would allow countries to continue using broadcast where required. Similarly, a secondary mobile allocation would allow some flexibility for use by mobile services, albeit limited in the case that broadcast continues to use the band due to the requirement to protect incumbent services.
For PMSE however, this may not represent an ideal outcome. PMSE currently operates under a footnoted secondary allocation (noting that PMSE operates under the mobile service, but that the footnote specifies usage by PMSE applications). A more general secondary allocation to the mobile service (open to IMT) would place PMSE at the same level of priority. Whilst IMT would likely only have access to the spectrum having secured licences (generally national) through auction proceedings, the two services having the same level of priority could reduce the barrier to such an eventuality occurring.
The impacts of spectrum allocation changes
Loss of spectrum for any industry is difficult. During clearance of the 700 MHz band for mobile services, PMSE users in the UK and many European countries were awarded grants to mitigate the impact of retuning existing equipment or purchasing new equipment. A similar arrangement could occur in the event of loss of further spectrum in the 470-694 MHz range. However, financial compensation may not be sufficient to mitigate all impacts, i.e., too little spectrum being available. For example, loss of the 600 MHz band in the US affected the Super Bowl, with insufficient PMSE spectrum available to support production of the event in some areas. To address this, special dispensation had to be granted by the FCC for exceptional use of the recently repacked 600 MHz spectrum during the event.
The PMSE industry has been arguing that it is reaching the point at which further reductions will affect its ability to continue to deliver services at the level expected. This message is beginning to be echoed by others outside of PMSE manufacturers as well. In the French national frequency agency’s (ANFR) ‘Paris 2024 Spectrum Management Plan’, it requests stakeholders use wired PMSE equipment wherever possible as it anticipates difficulties in securing sufficient spectrum for users. This issue is confounded by competition venues being near to central Paris where IMT deployments limit the extent to which PMSE can make use of historic PMSE bands, e.g., the 700 or 800 MHz bands, thereby limiting the extent to which a Super Bowl 600MHz type solution could be utilised.
Options for PMSE
In the event of further spectrum loss, options for PMSE are mainly to look to alternative technologies or frequency bands. For example, 5G (through URLLC, or ultra reliable low latency communications) could be well placed to deliver wireless performance of the level required by PMSE users. Trials are promising, but there are still improvements required to deliver on the most demanding requirements for the likes of IEMs in live events. A benefit of using IMT equipment is in the equipment and spectrum standardisation it achieves, effectively retaining some of the harmonisation benefits of the current 470-694 MHz band.
Conversely, even when using 5G equipment, there will need to be consideration on how PMSE users gain access to spectrum. For example, access to public 5G networks may not be able to deliver sufficiently high performance to meet the needs of PMSE users. Use of network slicing on public networks, or use of private networks, could be an option to ensure performance. The practical and economic case for network slicing for PMSE is relatively unexplored, but spectrum is increasingly being made available in C-Band for private networks in many countries. Operation of a private network would introduce a new burden on venues and PMSE users, however.
There is also the option of alternative permanent frequency bands. Unlicensed spectrum is available across many bands and countries, the operational requirements of which could be suitable for PMSE equipment. However, if these bands are outside the tuning range of existing equipment and no ecosystem exists in these bands, users would not be able to take advantage of their availability. Further, the propagation characteristics of alternative bands may not be able to replicate the performance of 470-694 MHz, particularly with regards to body loss.
In terms of alternative spectrum made available specifically for PMSE, several countries are in the process of, or have already, made additional spectrum available. For example, the UK has made spectrum in L-band available for PMSE, shared with aeronautical uses. This band has not been made available elsewhere, and as such equipment manufacturers have been hesitant to develop equipment for just the UK market. France is making additional spectrum available for the 2024 Olympics in amateur radio bands. This is likely to only be temporary, meaning that without developments in PMSE spectral efficiency, the PMSE spectrum scarcity issue expected during the Olympic Games may be encountered again in future.
Access to high coverage, high quality mobile broadband is vitally important across many countries and industries. WRC-23 Agenda Item 1.5 allows an opportunity to provide additional spectrum to the mobile service, thereby supporting aims to improve mobile services. However, regulators and industry need to be aware of the implications of introducing a mobile allocation. PMSE equipment, and sufficient access to appropriate spectrum, are hugely important to the content and events industries around the world. Technological developments have improved PMSE equipment’s ability to deliver services within the spectrum available, but the spectrum allocation changes being considered at WRC-23 risk materially affecting the ability to provide the levels of reliability and service required. Managing the band in the face of this disparate demand will be challenging and require a careful and considered approach.
Access Partnership is closely tracking this issue and, through its expertise across the technical, policy, and regulatory sectors, is well placed to provide necessary support on the issues raised. Please contact firstname.lastname@example.org for more information.