UK regulator Ofcom is offering two options to current occupants of the 3.6-3.8 GHz band as it pursues more spectrum for 5G.

The band has been identified by the regulator as suitable for future mobile use, and part of it is already authorised for mobile and fixed communications.

But Ofcom wants to take more. It points out national regulators across Europe have identified the wider 3.4-3.8 GHz band as suitable for 5G. Ofcom itself is readying an award of 150 MHz in the lower part of the band at 3.4 to 3.6 GHz.

While currently occupied by point-to-point fixed providers, and satellite services, the 3.6-3.8 GHz band has low intensity of usage.

Freeing up the band would involve eventually awarding 116 MHz not currently used for mobile services.

But analysis shows large separation distances are required to prevent interference in the band, raising a question how mobile operators would share with the band’s incumbents.

Ofcom said it has two options. In the first, incumbents’ current authorisation would continue. Mobile licences would have terms and conditions aimed at preventing interference. Given the large separation distances required, this would likely deny mobile operators in the band access to large geographic areas around the UK. The regulator would consider reviewing spectrum fees for existing occupants of the band to reflect this, Ofcom said.

The second option is to remove incumbents’ authorisation, so the fixed links and satellite providers would no longer be licensed to use the band, with appropriate notice being given.

New mobile licences would include interim terms and conditions aimed at preventing interference until the end of the notice period to minimise disruption.