Licence-Exemption Framework Review A consultation on the framework for managing spectrum used by Licence-exempt devices May 2007

Contents Previous work on licence-exemption The current situation with licence-exemption Key aims and objectives from licence-exempt spectrum The key proposals Our vision for licence exempt spectrum

In the SFR we said that there are three possible ways to manage spectrum Command & Control Regime Ofcom manages it Market Forces Regime Companies manage it Licence-exempt Regime Nobody manages it Approach that is currently adopted for about 94%+ of the spectrum Approach advocated by Cave and implemented by trading and liberalisation Approach currently adopted for 6%+ of spectrum, some argue for radical increase We need to decide the right balance between the regimes. Regimes are currently demarcated by frequency. However, there are also dimensions of power and time. + The spectrum percentages correspond to frequencies up to 60 GHz, exclude spectrum used by the MoD, and represent percentages of amounts of spectrum bandwidth relative to the band centre frequency, rather than absolute amounts.

The SFR discussion of licence-exemption (LE) Increasing licence-exempt allocation to 7%+ of total spectrum allows enough for everyone to install equipment capable of delivering 100Mbits/s data services in homes or offices. Key area for innovation but we do not need much more. Focus on removing restrictions, e.g. higher power in rural areas. Today 6% 7% 2010 + The spectrum percentages correspond to frequencies up to 60 GHz, exclude spectrum used by the MoD, and represent percentages of amounts of spectrum bandwidth relative to the band centre frequency, rather than absolute amounts.

Higher power LE usage in rural areas We studied the technical and economic issues associated with higher power LE usage in rural areas in detail. The business case was marginal because there were few homes and businesses that were unable to obtain broadband access. Interference concerns were significant In rural areas there might be interference to areas such as airports and motorways. There was a risk that rural devices would be used in urban areas. As a result, we concluded that there was insufficient benefit to outweigh the risks of increasing the power in rural areas Unserved households in the UK

Contents Previous work on licence-exemption The current situation with licence-exemption Key aims and objectives from licence-exempt spectrum The key proposals Our vision for licence exempt spectrum

Spectrum used by licence-exempt devices A wide range of bands are used by LE devices. At frequencies below 1 GHz these tend to be narrow and fragmented, supporting low-rate (e.g. telemetry) services. By far the highest value is delivered within the 2.4 GHz band Unanswered questions: Should we have more spectrum for LE? Should these be for specific applications? What rules should apply to LE devices? Should all spectrum above a certain frequency and below a certain power be LE?

Current LE bands are lightly used At 2.4GHz average utilisation is 10% Red bar gives mean utilisation, grey boxes provide max and min recorded levels

Delivering on the vision of the SFR In the SFR we suggested an increase in LE spectrum of 1%, relating perhaps to an additional 200MHz at 5GHz Our recent measurements suggest a low level of utilisation of LE spectrum, especially in the existing 5GHz bands Hence, there seems little reason at this stage to extend the LE allocation in these bands We will keep this under review but at present do not expect to provide additional LE spectrum by 2010 at 5GHz

Contents Previous work on licence-exemption The current situation with licence-exemption Key aims and objectives from licence-exempt spectrum The key proposals Our vision for licence exempt spectrum

1: Higher economic value 2: Supply exceeds demand Licence exemption may be appropriate in some cases to maximise the efficient use of the spectrum Ofcom’s main objective is to maximise the efficient use of the spectrum – measured in terms of economic efficiency There are two reasons why making a band licence-exempt might achieve this 1: Higher economic value Making a band LE might result in more economic value than licensing it. To test this we need to make a forward prediction of use under licensed and LE usage 2: Supply exceeds demand In some bands, particularly at very high frequencies, there is more supply than demand and hence licensing imposes an unnecessary bureaucratic burden

A preference for international coordination In general, we prefer the market to achieve coordination and harmonisation through trading and change of use of spectrum in multiple countries However, LE spectrum requires regulatory intervention to identify the spectrum and establish the rules for its operation giving little opportunity for market forces to modify parameters As a result, it would generally be preferable for regulators to coordinate internationally as far as possible in order to achieve harmonised strategies and allocations We will work with CEPT, EC and ITU to aim for a harmonised approach to LE spectrum as far as possible although equally we will not unduly delay our initiatives if harmonisation appears difficult to achieve

Contents Previous work on licence-exemption The current situation with licence exemption Key aims and objectives from licence-exempt spectrum The key proposals Our vision for licence exempt spectrum

Our proposals fall into three key areas Better use of LE spectrum LE above a given frequency LE below a given power level Adoption of shared LE bands but with zoning by power and use of politeness protocols Above 60GHz most of the spectrum can be made LE At similar power levels to UWB usage can be made exempt

Better use of LE (1): Making bands available for a range of applications Some bands are reserved for particular applications (eg DECT) while others are more generally available (eg 2.4GHz) Making a band application-specific tends to reduce the probability of interference but also reduces the utilisation and scope for innovation Similar levels of interference control can be achieved through “zoning” and the use of politeness protocols – this is our preferred approach Zoning The division of the LE bands into those for low power or low utilisation devices and those for higher power/utilisation devices since high power devices tend to crowd out lower power ones. A role for the regulator Politeness protocols Techniques such as “listen before talk” to ensure that all users get a fair share of access to the spectrum and that different technologies do not attempt to drown each other out A role for the standards bodies

Making better use of LE (2): Limited use of light licensing Light licensing is an approach where anyone wanting to use the spectrum has to register their details in a database Varying degrees of light licensing might require them to resolve interference if it is their fault Benefits include An ability to coordinate with incumbents such as satellite operators to work around particular geographical areas Lower risk of interference for users under some regimes In general, we believe that devices will increasingly be able to deliver the same low risk of interference through self-coordination We accept that this is not the case yet and that light licensing will have a role to play We expect to make decreasing use of it over time

LE above a given frequency At higher frequencies the spectrum is increasingly little used This is due to the poor propagation and high equipment costs The probability of interference is low because of the low range of devices This results in an area of spectrum where supply exceeds demand and hence licensing is unnecessary There is some use in these bands, and given that there is excess supply we propose to leave existing use unchanged Licence-exempt Light-licensed Licensed

Exemption of low-power transmitters Below a certain power level devices generally do not cause material interference The FCC has long had a “Part 15” limit below which devices are allowed to operate without a licence The UWB legislation effectively sets a low power limit in Europe We propose to extend this above 10GHz Below 10GHz the line shows the UWB limits. Above 10GHz the upper line is our proposal for low-sensitivity applications and the lower line for high sensitivity applications

Exemption of low-power transmitters (1) Radio devices which transmit at sufficiently low power levels do not cause material interference. Such devices are candidates for licence-exemption. Can we define generic power limits below which all transmitters are exempt from licensing? The FCC has long had a Part 15 limit below which devices are allowed to operate without a licence. The UWB legislation effectively sets such power limits in Europe (for transmitter bandwidths greater than 50 MHz). We propose generic radiation power limits that are: 1) based on UWB limits for frequencies < 10.6 GHz. 2) based on a relaxation of UWB limits for frequencies > 10.6 GHz. and below which all transmitters are exempt from licensing.

Exemption of low-power transmitters (2) Proposed generic radiation power limits (guidelines): Relaxed limits for underlay co-existence with insensitive services (20 dB/decade) UWB Limits Relaxed limits for underlay co-existence with sensitive (e.g. passive) services (20 dB/decade) 10.6 GHz

Exemption of low-power transmitters (3) Limits on mean EIRP spectral density, such that aggregate interference from transmitters exceeds 5% of ambient noise with a probability of 0.1%. 2 m2 Activity factor 100% Min. distance 0.15 m UWB 0.5 m2 0.05 m2 Activity factor 5% Min. distance 2 m Free-space link-budget deteriorates with the square of frequency for a specific receiver antenna gain. Increasing EIRPs can be tolerated at higher frequencies, with incumbent receivers experiencing the same marginal degradation in their performance.

Contents Previous work on licence-exemption The current situation with licence exemption Key aims and objectives from licence-exempt spectrum The key proposals Our vision for licence exempt spectrum

The Ofcom licence-exempt spectrum vision We will providing spectrum for licence-exempt use where it will enhance the efficiency of spectrum use Our preference will be for the spectrum to be used by a wide range of applications, subject to regulator-defined constraints on radiated power characteristics, and authorised polite protocols defined by standardisation bodies We support the licence-exempt usage of unused high-frequency bands, especially those above 100 GHz We support the exemption from licensing of all low-power transmissions below the UWB limits (with a relaxation of those limits at frequencies above 10.6 GHz)

Consultation questions (1) Q1: Do you agree that the spectrum commons model should be the preferred approach for licence-exempt use of spectrum, and that application-specific allocations should only be considered where technical constraints or safety issues require this? Q2: Do you agree with the proposal for multiple classes of spectrum commons? Q3: Do you agree with the distinction made between the licence-exemption and light-licensing regimes? Q4: Do you agree with the view that the licence-exemption and light-licensing regimes will converge in the future? Q5: Do you agree with the proposed mixture of licence-exempt and light-licensed use of the 105−275 GHz spectrum? Do you agree with the bands that have been identified for such use?

Consultation questions (2) Q6: Do you agree with the view that the use of the 275−1000 GHz spectrum should be licence-exempt? Q7: Do you agree with the view on the levels of future demand for licence-exempt usage in the 40−105 GHz spectrum? Do you agree that the Group-A bands identified above should be considered for licence-exempt use? Do you agree that licence-exempt and light-licensed use of the Group-C bands identified above should only be considered when there is evidence of demand for such use? Q8: Do you think it could be desirable for transmissions at levels below certain power spectral density limits to be exempt from licensing? Q9: Do you agree with the transmission limits proposed in this document? Q10: Do you agree with the harmonisation strategy discussed above in the context of licence-exempt devices? Q11: Do you agree with the view that no additional regulatory instruments, beyond those available today, are required for the protection of licence-exempt equipment?

Consultation Info For more information on the LEFR consultation http://www.ofcom.org.uk/consult/condocs/lefr/ For more information on other open Ofcom Consultations http://www.ofcom.org.uk/consult/condocs/?sector=Radiocommunications&open=Yes&submit=Go For more information on closed Ofcom Consultations or regulatory statements http://www.ofcom.org.uk/consult/condocs/?open=No&sector=Radiocommunications