Kognitiv radio kan gi mobilt superbredbånd Pål Grønsund, Telenor ASA Telecruise 2014
2 Cognitive radio is an intelligent and flexible radio system that can observe and learn from the environment and adapt accordingly
3 Power Spectral Density but not well utilized 0 1 2 3 4 5 6 GHz
Cognitive Radio can be used to dynamically access spectrum that is underutilized Frequency Spectrum Holes (White Spaces) Power Cognitive Radio Time t 1 t 2 t 3 Spectrum occupied by licensed users 4
There are mainly two methods to obtain information about available spectrum Spectrum Sensing Spectrum Database embedded sensors external sensors 5
The first commercial use of Cognitive Radio is in the TV White Spaces Frequency bands: Channel bandwidth: 54-698 MHz 6, 7 or 8 MHz 6
No. of available TV channels As an example, there were on average 19.9 available TV channels in Germany (ie. 160 MHz) 40 36 32 28 24 20 16 12 6 4 7 but there are fewer channels in urban than in rural areas. Beek, J. and Riihijärvi, J., TV White Spaces in Europe, in IEEE Transactions on Mobile Computing, vol. 11, no. 2, Feb. 2012. 0
Big players in the IT industry are investing billions of dollars in TV White Space technology Industry-led trials and pilots over the past two years have clearly demonstrated that TV White Spaces are just the beginning well-suited to provide low cost connectivity to rural communities with poor telecommunication infrastructure, and for expanding coverage in densely populated urban areas. but mobile operators do not seem to be very interested in cognitive radio, mainly due to the threat to their existing business. 8
Cognitive Radio will be allowed in other bands, TV White Spaces is considered a first step Radar bands S-band: 2700 3100 MHz C-band: 5200 5850 MHz The aeronautical band? 960 1215 MHz 9
Power Spectral Density What about Cognitive Radio operation in spectrum bands used for mobile communication? Quite high utilization, but not in all areas 0 1 2 3 4 5 6 GHz but there are approaches such as Authorized Shared Access (ASA) for licensed sharing of underutilized spectrum by a limited number of users. 10
Cognitive Radio brings threats and opportunities for the mobile operator Threats Reduced value of spectrum licenses Increased interference if other cognitive radios uses the mobile operator s own spectrum Increased (unfair) competition Opportunities Access to more spectrum in existing networks Opportunity to access spectrum in new markets 11
There are numerous use cases for cognitive radio, many that are attractive for mobile operators Cognitive Femtocell Cellular extension Rural broadband Backhaul 12
Offloading the LTE network using Cognitive Femtocells aided by a sensor network 1) deploy cognitive femtocells 2) deploy sensors 3) increase power 13 P. Grønsund, O. Grøndalen and M. Lähteenoja, Business Case Evaluations of LTE Network Offloading with Cognitive Femtocells, Telecommunications Policy, vol. 37, no. 2-3, pp. 140-153, Mar.-Apr. 2013.
We compare with the case of using conventional femtocells and additional base stations 1) deploy conventional femtocells 2) deploy macro base stations 14
Accumulated Costs [M ] Offloading LTE with cognitive femtocells can be more cost effective than using conventional femtocells and new base stations 21 18 15 12 9 6 3 Cognitive Femtocell Case Conventional Femtocell and new BS case 0 2017 2018 2019 2020 2021 2022 Year The most business critical parameters for the cognitive femotcell: cost for backhaul number of users supported coverage radius 15
In summary, Cognitive Radio can be used to provide wireless broadband at lower costs Cognitive Radio can be used to dynamically access spectrum that is underutilized. The first commercial use of Cognitive Radio is in the TV White Spaces, but this might just be the beginning. There are numerous use cases for cognitive radio that are attractive for mobile operators. Cognitive Femtocell Cellular extension Rural broadband Backhaul 16 Pål Grønsund (Pal.Gronsund@telenor.com) http://palgronsund.com, @palgronsund