Ofcom Look to Release More of the 1.4GHz Band for UK Mobile

Ofcom has today begun seeking feedback on the possibility of releasing another chunk of the 1.4GHz radio spectrum band – specifically the 25MHz slice of frequency between 1492-1517MHz – for use by modern 4G, 5G or even future 6G based UK mobile and mobile broadband networks.

At present both Three UK and Vodafone are already harnessing part of the L-Band spectrum (i.e 1452-1492MHz) to boost their mobile data connectivity (example) – mostly as a Supplemental Downlink (SDL) solution. But Ofcom has also been working to clear and re-purpose the additional frequency between 1492-1517MHz (here) for use by mobile operators, although it hasn’t been an easy task.

The problem is that the adjacent block of spectrum in the 1.5GHz band is currently used to operate Inmarsat‘s emergency communication satellite terminals on ships at and near ports, and on aircraft at and above airports. Use of 1492-1517MHz for mobile services is thus likely to cause interference to the receivers in these satellite terminals.

However, the regulator has now completed its technical analysis of the problem, which suggests that the band could potentially still be used for mobile and all while protecting the aformentioned users. But to do this would require specific power limits around ports and airports.

Ofcom’s Proposals

In order to protect these satellite terminals from new mobile use of the 1492-1517 MHz block, we propose to:

– define areas at ports and airports in which power flux density (“PFD”) from mobile base stations must not exceed certain limits (“PFD limited zones”); and

– define larger areas around these PFD limited areas within which new mobile base station installations will be coordinated to ensure that PFD limits are not exceeded within the ports and airports (“coordination zones”).

We are seeking stakeholders’ views on this initial proposal, as well as on how we should define these PFD limited zones and coordination zones. In this document, we explain our initial view that these zones could be defined by either simple or complex polygons, and we are interested in stakeholders’ views on these options, as well as other options they consider might be appropriate.

Options for making this spectrum available

Our initial view is that it may be appropriate to use an auction to authorise use of the 1492-1517 MHz block. We are also seeking stakeholders’ views on the format of a potential auction, as well as the most appropriate lot sizes.

The regulator is seeking feedback on all this by 12th January 2024 and will then set out their proposals for the band in another consultation, which seems likely to drop around the middle of next year. The real advantage of 1.4GHz is the fact that it’s able to deliver a fairly strong level of coverage and with reasonably decent data speeds, albeit somewhat dependent upon whether the device being used is able to harness the extended frequency.