Ofcom Update on the TV White Space issues Andy Gowans, SPG, Ofcom UK 18th November 2009 IEEE802 Interim Meeting Atlanta 18 th November 2009

1 Contents Interleaved Spectrum or TV White Space – Ofcom Consultation – European Studies – Next Steps

2 Ofcom Consultations on TV White Space 2nd consultation on DDR band manager award published 27/06/09 and closing date 27/09/09. For details see This will determine how and who PMSE users in the band will be managed in the future. Statement on Cognitive Radio Consultation published 01/07/09 see ; Consultation on Geolocation for Cognitive Access A discussion on using geolocation to enable licence exempt access to the interleaved spectrum published 17/11/09 see ;

3 –Sensing We were not convinced by the arguments that suggested that detection alone cannot offer adequate protection. However, we noted that implementation of detection-only devices at the sensing levels being requested is likely to be many years away. We also concluded that there was little advantage in rapidly making UK only regulations so we decided to await to align where appropriate with any European or international regulations being developed for sensing.. –Geolocation Geolocation databases appear to bring some advantages in terms of reducing the probability of harmful interference while enabling efficient use of spectrum, but we fully recognise the practical difficulties associated with this approach. We seen advantages and disadvantages to both detection and geolocation databases. We concluded to enable both detection and geolocation databases and allow stakeholders to determine which approach they prefer. Indeed, both approaches could even be amalgamated. We also provisionally concluded on the parameters needed for sensing but noted that further discussion would be needed as to how a geolocation database might operate. This latest consultation and discussion document is intended to stimulate and inform such discussion. Previous Statement on Cognitive Radio Consultation

4 Key parameters for devices from the July statement PMSE Cognitive ParameterValue Sensitivity assuming a 0 dBi antenna-120 dBm in 8 MHz channel (DTT) -126 dBm in 200 kHz channel (wireless microphones) Transmit power4 dBm (adjacent channels) to 17 dBm Transmit-power controlRequired BandwidthUnlimited Out-of-band performance< -46 dBm Time between sensing< 1 second Table above sets out the key parameters for Sensing that we concluded upon in July statement and have subsequently proposed for use in studies taking place in Europe (ECC SE PT43). See previous paper ofcom-update-on-the-digital-dividend – Cognitive for more details on how these parameters were derived. MERGED RESULTS SENSING

5 The new Ofcom consultation on geolocation We realise that the signal levels for sensing proposed in the July statement are extremely low, so we believe this alternative approach needed to be considered further. We see geolocation as a promising alternative to sensing. This is where cognitive devices measure their location and make use of a “geolocation” database to determine which frequencies they can use at their current location. Devices are prohibited from transmitting until they have successfully determined from the database which frequencies, if any, they are able to transmit on in their location. This new consultation and discussion document focuses on geolocation and the mechanisms likely to be needed for it to work. It is intended to aid the thinking that is taking place around the world on geolocation rather than as a statement of clear regulatory intent. As such, it is hoped that it will further discussion and speed the development of possible geolocation solutions. It does not seek to change in any way the decisions on general cognitive access and sensing set out in our July 2009 statement. GEOLOCATION

6 Key parameters being discussed in Consultation PMSE GEOLOCATION Based on previous work and workshops held with key stakeholders we believe that the key issues to be addressed in developing a geolocation approach are: 1.The information to be provided by the device to the database(s). 2.The information returned from the database(s) to the device. 3.The frequency of update of the database(s) and hence the periodicity with which devices will need to re-consult. 4.The modelling algorithms and device parameters to be used to populate the database(s). 5.The maintenance of the database(s). See for full details.

7 Key parameters being discussed in Consultation PMSE GEOLOCATION 1.The information to be provided by the device to the database(s). We suggest that this be flexible with the device allowed to select from providing only its location through to providing location, locational accuracy, device type and preferences as to the amount of information that it receives. As the device provides additional information the database can tailor its response, in some cases allowing higher power levels. We note that this may require standardisation work around the protocols to be used.

8 Key parameters being discussed in Consultation PMSE GEOLOCATION 2.The information returned from the database(s) to the device. We suggest that this should be a list of frequencies and power levels for each geographical pixel or location. Alternatively, if the device has moved to a different country, the database might return the address that the device now needs to send its enquiry to.

9 Key parameters being discussed in Consultation PMSE GEOLOCATION 3.The frequency of update of the database(s) and hence the periodicity with which devices will need to re- consult. Because some licensed uses of relevant frequencies might require access at short notice – for example some PMSE users - we suggest that devices be required to recheck the database at least every two hours.

10 Key parameters being discussed in Consultation PMSE GEOLOCATION 4.The modelling algorithms and device parameters to be used to populate the database(s). We make some detailed suggestions as to propagation algorithms, assumed device sensitivity and methodology that would enable the database to derive the list of frequencies that could be available for cognitive devices from the information provided about licensed use.

11 Key parameters being discussed in Consultation PMSE GEOLOCATION 5.The maintenance of the database(s). We note that someone will need to develop and host the database and that costs will be incurred. We seek views as to who should be responsible for the database and on what terms, where the costs might fall and what role it would be appropriate for regulators to play.

12 Contents Interleaved Spectrum or TV White Space – Ofcom Consultation – European Studies – Next Steps

13 European Developments on White Space Remit : To define technical and operational requirements for the operation of cognitive radio systems in the white spaces of the UHF broadcasting band ( MHz) to ensure the protection of incumbent radio services/systems and investigate the consequential amount of spectrum potentially available as “white space Two correspondence groups established –Determination of detection thresholds –Requirement for Geolocation database Status of the work and meeting documents can be found at : > ECC Activities > WGSE > SE43www.ero.dk CEPT Work (ECC SE PT43) established June 09 European alignment can occur through informal, semi-formal or mandatory processes. An informal route would entail all countries individually selecting the same standard. A semi- formal route might be via a CEPT recommendation that was widely adopted. A mandatory process might be via European Union (EU) legislation Technical work is now taking place within CEPT group SE43 on cognitive access, although this is at an early stage.

14 Contents Interleaved Spectrum or TV White Space – Ofcom Consultation – European Studies – Next Steps

15 Closing date for the comments on the Ofcom consultation/discussion document by 9 February We will give due consideration to all responses in determining the most appropriate course of action. See for more detail. If we decide to work internationally to achieve harmonisation, it may take some time, perhaps years, for all the necessary processes to be concluded. At present, the key points of interaction are with the FCC and the White Spaces Coalition in the US and within CEPT and the EU in Europe. Once we are satisfied that we have taken all relevant factors into account (possibly including further consultation) and done all that we can to ensure appropriate international harmonisation, we will proceed with the necessary steps to licence exempt cognitive access to interleaved spectrum in the UK. This may involve further consultation including draft regulations and then, in the light of responses, making those regulations. Because we do not yet know whether and in what form international harmonisation might be achieved, we cannot give guidance as to how long it might take to reach this stage The PMSE Band Manager award in the UK may have effect on our deliberations on the use of cognitive systems in the white space also as this will determine how and who will manage the PMSE community in this band in the future. Next Steps