The changes will allow the operator to deploy a dual-band massive MIMO solution capable of supporting with 3.4-3.8GHz and 3.9GHz band
UK regulator Ofcom has opened a consultation after mobile operator Three UK (Hutchison 3G or H3G) asked it to vary its existing 3.9GHz licence to enable it to broaden its 5G fixed wireless access (FWA) packages. The operator gained the FWA (3925 – 4009MHz) spectrum after its acquisition of UK Broadband (UKB) in 2017.
Ofcom is proposing to vary the technical terms in the 3.9GHz licence in line with H3G’s request to support 5G technology. The regulator believes such a move can bring additional benefits to consumers without creating harmful interference for other spectrum users. In reviewing H3G’s request, Ofcom also identified an opportunity to update the terms of access to 3.9 GHz spectrum to better align with its policy objectives for the wider 3.8–4.2 GHz band.
The regulator is therefore proposing to clarify how H3G can reserve spectrum under its 3.9 GHz licence, consistent with the first-come-first-served, shared framework for all users in the 3.8–4.2 GHz band. Specifically, it is proposing to introduce a requirement for H3G to use the spectrum ‘assignments’ that it requests. This is like the requirement already in place for Shared Access users in the band. Ofcom will phase in this requirement over five years.
It is also proposing to change the technical assumptions used for coordinating H3G with Shared Access users. These changes will reduce the area “sterilised by each of H3G’s assignments.” By that Ofcom pointed out that H3G currently has around 26,000 assignments (at nearly 9,000 locations across the UK) in the 3.9 GHz spectrum. “These assignments are currently not in use and prevent other users from accessing this spectrum,” said the regulator.
What the changes mean
Following the variation, 3UK will hold 84MHz of contiguous spectrum in the band to improve and expand its FWA service in the UK. The licence variation would allow 3UK to deploy 5G and Adaptive Antenna System (AAS). The variations will also align the technical conditions of the 3.9GHz licence with UKB’s 3.6GHz holding but keeping the same power level as existing 3.9GHz licence. 3UK plans to offload 5G FWA traffic from 3.4-3.8GHz to dedicated 3.9GHz.
The current conditions include an outdated and restrictive emissions mask, preventing 3UK from utilising standard equipment for any 5G deployment. Furthermore, the current licence lacks specific AAS conditions for base station maximum power and out-of-band emissions masks. Without these AAS conditions, 3UK will be unable to deploy massive MIMO. “Producing a UK-specific variant to meet our licence conditions is not justifiable due to low volumes and increased production costs. As a result, approving the proposed licence variation would allow 3UK to deploy a dual-band Massive multiple-input multiple-output (massive MIMO) solution capable of supporting with 3.4-3.8 GHz and 3.9 GHz band, thereby reducing the requirement for specialized equipment,” stated Ofcom.
Shared access
In the UK, the 3.8-4.2GHz band is mainly used by Shared Access licensees, satellite earth station, point-to-point fixed links, private network providers and FWA provided by 3UK. Ofcom has stated in its Evolution of Shared Access Licence Framework consultation that the popularity of the 3.8-4.2 GHz band reflects its suitability for a range of newer 5G use cases, with a developing 5G ecosystem and significant bandwidths available. However, with the current licence conditions, obtaining 5G equipment is currently difficult.
Ofcom said the proposed variation licence will allow 3UK to align technical conditions with other 5G licences and with Shared Access Licences. It added this shouldn’t have an adverse impact because 3UK is proposing to vary the technical requirements of the 3.9GHz licence with other 5G licences such as 3.6 GHz but is not proposing to increase the base station power levels. In addition, in its Shared Access Licence Guidance document Ofcom already has in place a “parties should work together and reach a mutual agreement” clause on dealing with adjacent channels potentially causing interference.
Old Millicom licence
UKB is the latest in a long succession of companies to have held the 3.9GHz licence since it was initially granted in 1992 by the Radiocommunications Agency to Millicom. The licence originally gave access to 2 x 84MHz of spectrum at 3605-3689 MHz and 3925-4009MHz for use in FDD form and was subsequently partitioned into two separate licences as part of Ofcom’s decision to vary UKB’s spectrum access licence for 3.6GHz spectrum.
The regulator is not currently proposing to change the level or structure of fees for the 3.9GHz licence for now, but it may be subject to review in the future. The consultation runs until 15 July 2024, and the regulator plans to publish its final decision in Q4 2024.