Tv white space reusing old spectrum in innovative ways - Networkshop44
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TV White Spaces (TVWS) are unused frequencies made available following the analog to digital TV switchover. A TVWS network can provide rural broadband or community internet access using available TV spectrum. Nominet tested a TVWS network in Oxford to connect sensors in a park to the internet, establishing a point-to-point link of over 470 meters. While TVWS has potential for extending connectivity, its use depends on location and spectrum availability may not be guaranteed. Further development is still needed to make TVWS radios and networks more user-friendly.
Tv white space reusing old spectrum in innovative ways - Networkshop44
- 1. TV White Space: Reusing old spectrum in innovative ways Pasquale Cataldi
- 3. TV White Space Reusing old spectrum in innovative ways Networkshop44 - 22 March 2016 @P_Cataldi - #TVWS Pasquale Cataldi
- 4. Outline 1. About Nominet 2. TV White Spaces • What it is • How it works • Use cases 3. The Oxford Flood Network 4. Conclusion #nws44 #TVWS4
- 5. About Nominet Nominet has run the .uk internet domain since 1996, managing a key part of the internet infrastructure 10 million internet domains on .uk registry, handling between 4 – 5 billion DNS requests per day Private not-for-profit company run for public benefit #nws44 #TVWS5
- 6. Nominet R&D Investigating emerging technologies that may have a impact on the Internet Applied research group Expertise across a wide range of topics Work and partner with all types of organisations globally Active contributors to internet standards #nws44 #TVWS6
- 7. Spectrum is a finite (and valuable) resource Demand for spectrum over the next decade will outstrip supply We can manage it more intelligently and meet the demand A win for governments, businesses and consumers The UK frequency allocation table …an empty box of chocolate #nws44 #TVWS7
- 8. TV white spaces TV white spaces are frequencies made available following the analogue to digital switch over #nws44 #TVWS8 •Line-of-sight not required •Up to 10 Km outdoor •Enhance indoor connectivity Superior propagation characteristics •ADSL-comparable performance •Carrier grade radios Great performance •No operator required •No need for complex infrastructure (like 3G/4G) Competitive cost
- 9. Sharing TV band DTT broadcasters (and wireless microphones, PMSE) operate in this spectrum and have priority TVWS access for other uses needs to be managed carefully to protect priority users TVWS is the ideal test-bed for smart spectrum management #nws44 #TVWS9
- 10. Accessing the available spectrum Geo-Location Database (WSDB) “Ask” before transmitting Spectrum Sensing “Sense” before transmitting It is easier to implement a database approach 1. No hidden-terminal problem 2. Easier to manage spectrum and enforce policies 3. Complexity in the cloud, not on the radios #nws44 #TVWS10
- 11. Ofcom regulatory framework List of qualified WSDBs TVWS availability maps for protection of DTT Details of PMSE assignments Whitespace Database(s) Master deviceSlave device TV Band WSDBs get updates about DTT and PMSE from Ofcom Upon request from a master device, a WSDB computes the maximum transmission power per channel Every 15 minutes masters must contact the WSDB to continue to transmit Whitespace Database(s) WSDBs #nws44 #TVWS11
- 12. Radios and WSDBs need to speak the same language The more databases radios can talk to, the better WSDBs want to make sure that they can interface with as many radios as possible PAWS standard The actual implementation of the protocol might change among different countries Although developed for TVWS, PAWS could be used for other portions of the spectrum #nws44 #TVWS12
- 13. TV white spaces have multiple uses Rural broadband Super Wi-Fi Emergency communications Internet of Things Community networks #nws44 #TVWS13
- 14. The Oxford Flood Network https://www.youtube.com/v/OWcx4lQy 5UI 14 #nws44 #TVWS
- 15. Getting data from some sensors to the Internet was challenging 1. There is no internet access in the park 2. 3G connection is flaky (and not free) 3. Directive LOS solutions would not work Solving a connectivity problem #nws44 #TVWS15 Our solution exploited multiple technologies 1. Sensors are connected to a hub through 868MHz radio modules 2. The hub is connected to the internet through a TVWS link (point-to-point) • Slave device close to the sensors • Master connected to the internet 3. We now also provide Wi-Fi connectivity to Hogacre Common
- 16. Master location – Speedwell House For the master location we initially selected Speedwell House 1. High building 2. Central location 3. County Council building 4. ~890 metres from slave However, Speedwell House is not a good location BT building in proximity of the master created too much interference BT building Speedwell (master + antenna) Hogacre Eco Park (slave + antenna) #nws44 #TVWS16
- 17. Master location - Chilswell Road We decided to move the master to a more suitable location to avoid the source of interference 1. Residential property on Chilswell Road 2. ~470 metres from slave We could establish the link without problems >16Mbps aggregated throughput #nws44 #TVWS17
- 18. Lessons learned from the Oxford Flood Network Areas poorly connected to the internet can greatly benefit from the use of TVWS Information from both WSDB and in-field measurements is necessary to optimally plan and deploy a TVWS network TVWS radios configuration might not be very user-friendly… like most radio devices, unfortunately #nws44 #TVWS18
- 19. Conclusion #nws44 #TVWS19 Spectrum management needs to become much smarter than it is nowadays Efficient spectrum sharing will undoubtedly happen in the future TVWS is an interesting technology to elegantly solve connectivity problems Great radio propagation characteristics at competitive cost Channel availability is not guaranteed - depends on location and time Awareness about TVWS needs to increase in the UK We do not expect a fast take-off in the adoption of this technology Applications will initially focus on alleviating the digital divide If you want to know more about TVWS opportunities, or deploy a TVWS network, come talk to us!
- 20. Q&A TVWS – It’s just the beginning Website nominet.uk Email Pasquale.Cataldi@no minet.uk Twitter @P_Cataldi - @Nominet R&D blog nominet.uk/researchbl
- 21. jisc.ac.uk Pasquale Cataldi nominet.uk Pasquale.Cataldi@nominet.uk @P_Cataldi - @Nominet nominet.uk/researchblog