Defence and armed forces – guidance

Sharing defence spectrum

The Ministry of Defence intends to open up some military frequency bands for new sharing opportunities for public and private sector users.

Demand for radio spectrum has grown significantly in recent years especially for the use of wireless broadband services accessed via smartphones, tablets and other mobile devices.

Mobile operators having migrated from 2G to 3G and now 4G networks to enable higher data rates and better quality services to be delivered, continually seek access to larger amounts of spectrum for their future use, to expand their networks and to deploy new technologies. This rapid increase in demand has led the UK government to actively consider ways of releasing spectrum by making new bands available for commercial exploitation.

As custodian and manager of nearly 30% of all UK radio spectrum the Ministry of Defence (MOD) has an obligation to make the best possible use of this scarce resource, by using it efficiently for operational purposes and by supporting an increasingly diverse set of services, applications and users with diverging requirements, whenever this can be done without compromising operational effectiveness.

The majority of MOD managed bands are already shared with a number of public and private sector organisations for national security, emergency services, science and transport. This adds to the complexity of making them available for other uses.

There are a number of aspects that need to be considered and weighed up together. These include the characteristic and sharing potential of each band, the need for coordination and harmonisation across countries and continents and how flexible the regulations must be to adapt to changing requirements. Incumbent users will have to be protected from interference from new users either coexisting in the band or in adjacent bands.

The avoidance of interference will require detailed analysis of existing users’ profiles as well as detailed modelling of potential new users’ profiles. The identification and prioritisation of bands will reflect the anticipated complexity associated with sharing with defence assignments, the availability of spectrum across the UK and the level of commercial interest MOD identifies.

Sharing models

In its simplest form spectrum sharing models can be categorized by two defining features; the first is whether the sharing can be defined as sharing among equals or primary-secondary sharing, and the second is whether the arrangement is based on cooperation or coexistence.

If the sharing arrangement comprises sharing among equals all devices have equal rights and typically more flexibility about how to avoid negatively impacting neighbours. Where sharing is based on cooperation devices communicate with each other to avoid mutual interference, where sharing is based on coexistence there is more of a risk of mutual interference. An important variation on this model is that of band manager where one entity is given a license to control a block of spectrum and the right to grant temporary access for a fee through a secondary market. Access may be for a short period (days) or for longer periods (years).

Primary-secondary is probably most useful for systems that need guaranteed quality of service but uses the spectrum infrequently i.e. the emergency services. Exchanges between primary-secondary operators provide an opportunity for the primary to guarantee quality of service for the secondary. It could also be an opportunity for the primary to demand payment.

Where sharing is based on cooperation the primary and secondary devices communicate with each other to avoid mutual interference. Where sharing is based on coexistence the secondary device is essentially invisible to the primary, which means that all the complexity of sharing is borne by the secondary user. Before sharing takes place under such arrangements rules must be established to protect the primary. Secondary devices will either be restricted to transmitting at such low power that they never cause harmful interference to the primary or they may be allowed to transmit opportunistically when it can be determined that transmission will not cause harmful interference.

Many factors must be considered when deciding to adopt a particular spectrum sharing arrangement, including potential gains in spectral efficiency and the ability to meet the needs of applicants regarding interference, protection, congestion and support for mobility. The most efficient and cost effective approach will depend on the type of systems involved, given the diversity of systems under current consideration broadcasting, public safety systems point-to-point links, multiple sharing models within given bands may have to be considered.

Sharing opportunities: update

MOD’s initial screening of bands identified the following as suitable for sharing.

870-872 & 915-917 MHz Returned to Ofcom for SRV use in line with EEC Regulations
1427–1452 MHz There is thought to be scope for sharing opportunities in a number of large urban areas
2025–2070 MHz Long term sharing agreement now in place to allow PMSE greater security of use
4800–4900 MHz There is thought to be scope for sharing opportunities in a number of regions across the UK
7900–7975 MHz There is thought to be scope for sharing opportunities in a number of regions across the UK
10–10.125 GHz Removed from sharing plans to allow cross-government sharing

An updated list can be found on page *** of the Ofcom CFI

The MOD welcomes requests for access to any of the spectrum bands where it is thought sharing opportunities exists. Responses will assist the MOD in gaining a more detailed understanding of potential shared uses, inform coexistence studies and assist the MOD in understanding the implications of new users on its own Defence use. This will enable the MOD to make decisions on the type, nature, scale, location and duration of any sharing possibilities.

Applying to share MOD spectrum

Complete the Sharing Defence Spectrum Application Form and post or email it to:

CTO Spectrum Policy 3
Ministry of Defence
Main Building

Email: Sharing Defence Spectrum

MOD will use the applications forms to inform the demand for sharing and may approach applicants for more information.

Applicants should note that the MOD is not obliged to enter into any trade and may refuse an application at any point prior to contract signing. Examples of reasons for refusal to trade may include unmanageable technical issues, issues relating to national security and the possibility that the application is likely to distort competition.

Contacting us

MOD welcomes the views of stakeholders on the potential use of MOD managed bands. You can contact us by post or preferably by email. Please include the following on any correspondence;

  • contact name, address and telephone number
  • organisation representing
  • your questions/feedback

In line with the UK government’s transparency agenda, MOD intends to publish on its website any feedback that will help inform the sharing process. Correspondents should note that such information will be totally non-attributable and will not contain personal data. If you provide information to us that you regard as commercially sensitive, please let us know in your response and we will not publish it.

Contact point

If you would like to discuss any of the issues raised on this webpage or need advice on the appropriate format for responses, please contact the following.

Spectrum Policy 3
Level 2 Zone M Desk 49
Main Building
London SW1A 2HB