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Spectrum reform in the UK: The development of Spectrum Usage Rights. Professor William Webb 2006. An introduction to our proposals for SURs. Background – The Spectrum Framework Review Selecting licence terms Associated issues Our Vision for Spectrum Management.
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Spectrum reform in the UK:The development of Spectrum Usage Rights Professor William Webb 2006
An introduction to our proposals for SURs • Background – The Spectrum Framework Review • Selecting licence terms • Associated issues • Our Vision for Spectrum Management
Ofcom’s Spectrum Management Agenda The Given: Fulfil our statutory duties Ensure optimal use of the spectrum Take account of the needs of all spectrum users Maximise economic benefits of the spectrum The Ambition: Make the UK the leading country for wireless investment & innovation A better signposted approach to spectrum, giving more certainty in the market A flexible approach to spectrum, providing opportunity for innovation A competitive communications market, providing opportunity for returns on investment
MF C&C L-E There are three possible ways to manage spectrum Command & Control ZoneOfcom manages it Market Forces ZoneCompanies manage it Licence-exempt Zone 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 Zones • Zones are currently demarcated by frequency. However, there are also dimensions of power and time
MF C&C L-E The Market Forces Zone Allocation(what the best use is for the spectrum) Assignment(who the best user is of the spectrum) Liberalisation Phase 1/2Users ask Ofcom if they can change the use “New” spectrum:Auctions Existing spectrum:Trading between users Liberalisation Phase 3Technology-neutral spectrum usage rights to allow users to make the change without consulting Ofcom 2004 0% 72% 2010
An introduction to our proposals for SURs • Background – The Spectrum Framework Review • Selecting licence terms • Associated issues • Our Vision for Spectrum Management
The “liberalisation” problem • A change of use by a licence holder may change the interference experienced by neighbours in both geography and spectrum terms • How to allow maximum flexibility without increasing uncertainty for neighbours? • Should the balance be towards caution or flexibility?
Our philosophy • A licence holder should not be adversely impacted by the actions of their neighbour unless • They agree • Or their neighbour has not taken up all their existing rights • The market is better able to determine optimal outcomes such as boundary conditions, than the regulator
Geographical PFD • Limiting EIRP • Simple, but does not provide certainty because a large number of base stations could be deployed near boundaries • Coordinating deployments • Guaranteed not to cause unexpected interference but how to decide what the rights are when agreement can’t be reached? • Aggregate PFD limit at boundary • Provides complete certainty to neighbour, licence holder has to conduct modelling or measurement to understand impact on their deployment • Proposed licence term • The aggregate PFD at or beyond [definition of boundary] should not exceed X dBW/m2/[reference bandwidth] at any height up to H m above local terrain for more than P% of the time
Out-of-band PFD • EIRP limit out of band • Currently used, but an increase in base station density increases interference levels • Technical coordination • Same issues as coordinating deployments • Use of a particular standard • Doesn’t meet the objectives of technical neutrality • PFD distribution across an area • Clearly defines probability of interference, although not actual locations where it will occur, difficult to measure but rights are clear • Proposed licence term • The OOB PFD at any point up to a height H m above ground level should not exceed XdBW/m2/MHz for more than Y% of the time at more than Z% of locations in any area A km2.
In-band PFD • Broadly the same problem as out-of-band • Could ignore on the basis that better receiver filters could be deployed – but this risks higher interference • Or treat in the same manner as out-of-band • Proposed licence term • The IB PFD at any point up to a height H m above ground level should not exceed XdBW/m2/MHz for more than Y% of the time at more than Z% of locations in any area A km2.
Indicative interference levels • A licence holder can work out the interference they can expect based on the sum of all the rights of neighbouring users plus noise floor and EMC-type emissions • This is not a “right” as such because of the vagaries of propagation • However, if they experience interference above this level they can investigate and call Ofcom if needed
An introduction to our proposals for SURs • Background – The Spectrum Framework Review • Selecting licence terms • Associated issues • Our Vision for Spectrum Management
Licenses are individual cells SURs work better in large areas • If a licence holder can expect interference in a particular area from more than one geographical neighbour then the allowed interference has to be divided among the neighbours – the “aggregation” problem • Difficult to do efficiently, and makes any subsequent negotiation more complex • If licences cover an area significantly larger than the coverage of a single transmitter then the chances of having more than one significant neighbour at any point is reduced • Equally, the value of changing licence parameters is likely larger for larger area licences • Therefore better to apply SURs to large area licences initially and then consider whether to cascade down Problem areas Licenses are areas
Negotiating with neighbours • Determine geographical neighbours by propagation modelling – at least direct neighbours • Determine frequency neighbours by modelling, at least 250% of channel bandwidth from band edge • Up to those making the change to ensure they include all relevant neighbours
Implementing within the current legal regime • If licence holders agree to a change in their boundary conditions they cannot currently make this change themselves • Licenses returned to Ofcom for approval, which will be forthcoming in most cases • In future consider changes to the legislation to allow licence holders to make these changes directly
An introduction to our proposals for SURs • Background – The Spectrum Framework Review • Selecting licence terms • Associated issues • Our Vision for Spectrum Management
The Ofcom Spectrum Vision • Spectrum should be free of technology, policy and usage constraints as far as possible • SURs are technology and usage neutral • It should be simple and transparent for licence holders to change the ownership and use of spectrum • SURs facilitate change of use • Rights of spectrum users should be clearly defined and users should feel comfortable that they will not be changed without good cause • SURs define rights more clearly than current licences