LSA Opens New Frequency Bands for Mobile Services
posted Dec 27, 2012 by Kari Heiska
The mobile industry has recently expressed their worries about the spectrum scarcity when it comes to the future capacity needs of the wireless broadband networks. It seem that the wireless community has reached a consensus that the spectrum needs of the fast growing mobile data traffic cannot be satisfied with re-farming of old bands for the new networks and services. In many cases the incumbent radio systems with existing users groups and ecosystem are strong; the performance and the cost of the old mature technology fit the requirements of the end customer optimally. Finding new replaceable harmonized frequency bands for the incumbent system would take too long compared to the need. In some cases there are no replaceable bands and technologies available at all.
LSA (Licensed Shared Access) is an enabling regulatory tool for opening new bands available for wireless broadband services and still allowing old incumbent services and technologies utilizing the bands. Geo-location database is a key enabler for the LSA regulatory regime. With the LSA databases the national regulators are able to control the interference levels and quality of the service for the incumbent as well as for the new services. The sharing between incumbents and new users can be realized in time, frequency and in location dimensions depending on the pre-defined sharing agreements and rules. The regulative foundations for the sharing scheme are based on the harmonized band plans, technical conditions and standards.
National administrations will need to consider the conditions and granting criteria for these new licenses. In addition to that national administrations need to find suitable way to convince incumbent service providers to compromise for given privileges. Incumbents need also to change their internal operating processes to make others aware of the coming operations, changes etc in their networks. The coordination between several operators of the new technology in the band has to be considered as well. This new era of spectrum usage will stimulate new innovative services once spectrum and new technologies are available for new user groups and networking service providers.
CEPT has started working on with the Licensed Shared Access. The ECC working group FM53 has already started its work. The target of the working group is among other things to report on sharing arrangements and band-specific conditions for the implementation of the LSA and to analyze the procedures for the assignments of the LSA. In addition to that the project group is considering the licensing scheme from the LSA licensee point of view: what are the requirements from the operator to be able to utilize the LSA bands in a reliable way. One of the first bands to utilize LSA is the 2.3 GHz band in Europe. The harmonization of the band is taken care of another CEPT group, FM52 which has also started its work. ETSI has also established a work item aimed at developing a System Reference Document (SRDoc) for mobile broadband services under LSA regime in the 2.3 GHz band.
So, many interesting things are happening in the areas of LSA and spectrum sharing .
Further information: firstname.lastname@example.org
Press release: Fairspectrum Provides TV White Space Database for Europe’s First Geolocation Radio License
HELSINKI, Finland. — Aug 27, 2012 – Fairspectrum Oy, a leader in the field of spectrum sharing technology, announced the deployment of Fairspectrum geolocation database in the communication system, which implements the Europe’s first TV White Space geolocation database radio license.
Finnish Communications Regulatory Authority (Ficora) has today issued a test radio license for cognitive radio devices on the TV White Space frequencies for Turku University of Applied Sciences. The license covers the 470-790 MHz frequency range and a 40 km x 40 km area surrounding Turku, Finland. The license is valid for one year. Nearly 300 000 people live in the radio license area. A geolocation database is an essential part of the license. The license is the first one in Europe having the geolocation database control of frequencies.
Spectrum sharing is a global solution for matching the increasing demand for wireless data communication and scarce frequency resources. TV White Space frequencies are a real world test laboratory of spectrum sharing. TV White Space can improve existing data communication services by increasing data rates or coverage area, it can make the services more cost efficient, and new services can be developed. Spectrum sharing in TV White Space is managed with a geolocation database. The geolocation database controls TV White Space device frequencies and transmission power so that the devices do not interfere other wireless communication systems like terrestrial TV or radio microphones.
Fairspectrum provides the geolocation database for the communication system according to the Ficora licence rules. Fairspectrum geolocation database applies geometrical computation in radio spectrum sharing. Geometrical computation makes Fairspectrum geolocation database efficient, fast, and easily customizable for various environments, regulations, and rules. The geometrical computation based rules can clearly be communicated between operators, regulators, and other users of the shared spectrum.
The issued license will be used in the WISE project. The WISE consortium consists of Nokia, Digita, Fairspectrum, Ficora, Turku University of Applied Sciences, University of Turku, and Aalto University.
WISE White space test environment for broadcast frequencies (WISE) is a Tekes funded research project in Finland, and it is a part of the Tekes Trial program. WISE studies efficient use of TV-band spectrum resources through cognitive radio technologies and geolocation databases. Tekes Trial program invites international experts and investments to benefit from its unique trial environment for cognitive radio and networks. For more information, visit http://wise.turkuamk.fi and http://www.tekes.fi/programmes/Trial.
Fairspectum is a Finnish startup applying Internet services and computational geometry in the field of radio spectrum sharing. For more information, visit http://www.fairspectrum.com.
Ficora is Finnish Communications Regulatory Authority. For more information, visit http://www.ficora.fi
TUAS is Turku University of Applied Sciences. It offers education that develops working life and entrepreneurship, research and development services (R&D) and holistic development of organisations. For more information, visit http://www.turkuamk.fi.
European industry has traditionally been very strong in mobile communication technologies, which currently best represented by the LTE mega-trend. It is interesting to think how LTE and TV White Space paths could cross. 700 MHz band is TV White Space in Europe and a LTE band in US. The US basestations and terminals can directly be used as White Space devices in Europe. A few improvements like flexible multiplex gap, availability of TDD devices, and understanding geolocation database communication would increase the applicability. TV White Space could form a part of LTE transmission. Most likely it could be used to connect femto or pico basestations to the core network on rural areas. TV White Space could become 3GPP radio interface technology at least in three different ways. Defining it as non-3GPP access like WiFi is already there. TV White Space frequencies could provide frequencies for carrier aggregation, or TV White Space frequencies would be added to the list of supported band with the specific features required by the shared spectrum use. It may be difficult to believe that the operators would begin invest in a radio network without any guarantees about availability of the spectrum. That coiuld be provided with the help of Authorised Shared Access aka. Licensed Shared Access (ASA/LSA). The problem can be turned around and consider how LTE technology could become a part of a White Space system. Which of the LTE components could be applied as such or with small modifications in a TV White Space communiation system: radio interface, Radio Resource Management (RRM), or Core Network (VN). Another radical thought would be to interpret the WRC outcome about use of 700 MHz band "broadcast and mobile systems as co-primaries" in a way that the co-primary definition would not be between continents or countries like typically, but between smaller areas like between GE06 allotments. This way the 700 MHz LTE systems could be deployed as White Space networks without clearing the 700 MHz from from broadcast. Why should we consider combining LTE and TV White Space? If we believe that we can combine the benefits of both worlds in the same system, it definitely becomes worth while as the benefits of these technologies are currently quite different. LTE has a huge eco-system. It attracts investments as large as GDB of a medium sized country, the radio technology represents state of the art and at the same time is thoroughly understood, studied and tested. Overall LTE deployment and business is very predictable. TV White Space has a huge growth potential, it is open for many innovations, and principles and processes can be applied to other frequency bands and frequency sharing with other types of systems.
Further information about LTE and TV White Space can be found in the Fairspectrum presentation in Tekes trial seminar on May 4, 2012.
A White Space geolocation database is a tool to bring the regulatory spectrum sharing principles in practice. It administers the frequency use of the same TV band between TV broadcasting, Program Making and Special Events (PMSE) equipment like wireless microphones, and TV White Space Devices.
Workshop on Cognitive radio and software defined radio, organized by ECC CEPT and a research project Cost-Terra in Mainz, Germany on May 2-3, 2012, presented a wide view of regulators, researchers, and industry on the topic. Spectrum Sharing is an umbrella term including cognitive radio and TV White Space in the European regulatory terminology. The basic categories of spectrum sharing are cognitive technologies and location based technologies, which are best represented by spectrum sensing and geolocation database technologies, respectively. Interestingly, the majority of workshop discussion was around location based TV White Space technologies.
TV White Space geolocation database facilitates the spectrum sharing collaboration between regulators, broadcasters, PMSE, and TV White Space industry. Although the geolocation database has been introduced by the TV White Space industry, the collaboration assumes that also broadcasters and wireless microphones participate in contributing information to the database and benefit by doing so. In the Mainz workshop, Fairspectrum demonstrated four concepts how to bring these industries together. Through the geolocation database field strength input interface, the broadcasters can contribute their service areas calculated by themselves to the geolocation database. With the PMSE Manager, the wireless microphone users can maintain the geolocation information about their device frequencies, location and operation time. The regulators can effectively communicate the PMSE regulations to the wireless microphone users with the Frequencies for PMSE; and with the White Space Device, the regulators and TV White Space industry can test, demonstrate, and visualize the operation of a geolocation database.
Please, find more information on the topics through the following links:
Cambridge Wireless hosted an excellent TV White Spaces workshop in Duxford, UK on Apr 25, 2012. There were three recognizable themes in the event: to wrap up the learning of the best known White Space trials in Europe, to summarize the current state of the art of White Space around the world, and to collect the fighting spirit for the commercial breakthrough of the TV White Spaces technology.
The World Radiocommunications Conference (WRC) 2012 discussed an accelerated schedule for allocation of 700 MHz band for mobile data communications in January and February 2012. It was a wake-up call for the European industries utilizing the TV UHF band: terrestrial TV broadcasting, Program Making and Special Events (PMSE) including radio microphones, and TV White Spaces. Pearse O’Donohue, Head of Radio Spectrum Policy in European Commission reminded that European Commission has not yet expressed its statement on the use of 700 MHz band, and he recommended that the current users of the 700 MHz band would join the forces to protect their interests. Following the same topic, Richard Thanki from University of Southampton emphasized that a slight increment on mobile spectrum of possible new 700 MHz band has a much smaller impact on people's lives than enabling a plethora of new services with TV White Space. These services were presented in a great overview of TV White Space potential applications by prof. William Webb from Neul.
In addition to the fantastic presentations, Cambridge TV White Spaces Trial Summit had a number of demonstrations. Without going to the details of the demonstrations, I still can feel the words of Kari Heiska, Digita: "Not so many years ago, LTE had same size of demonstration room, same number of stands, and same size of devices in the Mobile World Congress."
It is a privilege to belong to this group of people who have a clear mission to increase the efficiency of radio spectrum use, improve the communication services of the people in the world, and make those services more and more affordable by increasing competition.
The presentations of the event are available here.
The media visibility of TV White Spaces development in Europe is currently dominated by UK and specifically the Cambridge area. Last week, the Cambridge trials were demonstrated to the European regulators of CEPT SE43 working group. In the same event, Andrew Gowans presented the Ofcom views of TV White Space regulation and standardization. He divided the standardization need of technical issues in four different catogories with examples:
- Needs European harmonization in ETSI or CENELEC: White Space Devices (WSD) spectrum emission mask and conformance tests,
- Needs technical standardization in IEEE, 3GPP, Weightless SIG, or IETF: WSD radio interface,
- Decided by the local regulator: Accrediation of the database provider, and
- Manufacturer differentiation: Technical algorithm, which specifies the available TV channels and maximum transmission power,
The transfer from analog to digital broadcasting enables the TV White Space communication opportunity. Netherlands, Finland, and Sweden are forerunners in the analog switch off (ASO). UK has an interesting situation as it started the digital TV transmissions first in Europe, but the completion of ASO is still ongoing. A case study of TV White Spaces capacity in Finland confirms the fact that in the urban and highly populated areas there is less capacity available than on rural areas. A forecast of TV White Spaces diffusion is computed based on Bass diffusion model, the s-curve which has a slow start, an exponential growth phase and a saturation point. Nordic countries - and UK as an White Spaces exception - are expected to become early adopters. When the industry revenue per country is taken into account in the estimates, the large economies: Germany, UK, France, and Italy begin to dominate soon.
Fairspectrum representatives discuss TV White Spaces in the today published book TV White Space Spectrum Technologies: Regulations, Standards, and Applications.
When talking about TV White Space (TVWS), it is easy to remember that TVWS devices (WSD) should not cause interference to TV broadcasting, but they are not the only devices to protect. In a regulative context, the radio microphones are either specifically mentioned as an instance of Program Making and Special Events (PMSE) equipment or more generally, they are a part of other radio communication that should not be interfered. The principle is justified and easy to understand, but what does it mean in practice. Which TVWS device power levels cause interference to radio microphones? How far the devices still interfere the radio microphones? The Finnish Tekes WISE project decided to find this out and organized a measurement campaign in the largest theater in Helsinki, in Helsingin kaupungin teatteri. Among other results, the following observations related to a typical WSD use were made: in the audience the WSD interferes radio microphones both on the co-channel and on the adjacent channels. Within a distance of 100 m from the theatre building, the co-channel interference can be observed, but on the adjacent channels the probability of interference is very low. A half a kilometer away neither co-channel nor adjacent channel is a problem.
There are three commonly referred methods for TVWS and cognitive radio interference management: geolocation database, spectrum sensing, and cognitive pilot channel. In all regulations in which the TVWS operation is specified, the geolocation database is chosen alone. In all measurement locations, we were able to detect the transmitting radio microphones with a spectrum analyzer, even if it was not possible to interfere the microphones anymore. This observation raises the discussion of need for spectrum sensing to detect the radio microphones. In many countries, the radio microphones need a licence for radio transmission. In practice, a relatively large portion of radio microphones are used without a licence, and even if the licence exists, the location of use is not specified. For a proper protection of the radio microphones with a geolocation database, either the radio microphone licensing should better cover the real use and the location of the radio microphones should be collected; or the WSD should implement a continuous spectral sensing on the co-channel and a few adjacent channels.
The measurement reports can be found in:
The related Fairspectrum letter (in Finnish) to the Ministry of Transport and Telecommunication can be found in:
The last number of the Finnish Prosessori-magazine writes how Finland could utilize unused TV frequencies. The article reports about Tekes WISE project. TV White Space (TVWS) communication technology offers excellent propagation characteristics and a broad bandwidth giving high bitrates for data connections also on the sub-urban and rural areas. The unique co-existence of various communication technologies on the same frequencies challenges the interference management. The TVWS systems should not cause interference to earlier built systems like TV broadcasting or radiomicrophones. The suggested solution for the interference management is a geo-location database in USA, UK, and Canada. Finnish radio regulators have not yet defined how to solve this issue. WISE project has carried out extensive measurements to understand how to balance between interference protection for priority systems and capacity and availability of the TVWS systems.
After a long day at work I returned home and parked my car on my own parking space. Next morning I was again waiting on a highway during the familiar rush hour, but luckily I did not have to look for a parking space at the office, as I had my one dedicated only to me. At least, this is how it used to be. First our office parking lot was converted to a first come - first served area, and when I moved closer to the center there was no dedicated parking spaces available anymore. Did someone ask, if I want to share my parking space with my colleges? If I was paying myself for the parking space, I might have been offered a more economical shared parking lot option. If my parking lot was dedicated to me, but the cost was shared by all employees i.e. paid on the company level, what would have been my motivation to give my dedicated parking lot for common good.
TV white space introduction has the same dilemma. The TV broadcasters, mobile, fixed, and satellite operators have their own dedicated frequency bands. The promoters of TV white space technology request them to begin to share something that has been in their own control. As the neighboring channels and physical areas are dedicated to someone, whose telephone number I know, I can contact them when I notice interference on my channels. What would motivate the current license holders to share their spectrum allocations, when they do not need them themselves? The regulators may set a policy that no other type of spectrum is available but to share the spectrum. The other option are the economical incentives. Either the use of shared spectrum should be of a lower cost or the spectrum holder should be able get additional income by allowing other users on their frequencies. Many countries will use a combination of all of these, and finding a balance between them will take some time, especially when the dedicated users are fighting for their dedicated parking spaces.
Finnish Ministry of Transport and Communications (LVM) organized a public hearing about the 800 MHz frequency band on Nov 14, 2011. In the resolution draft, one of the most argued points was the goal to strengthen the government budget with the auction of the band. It has been a common practice in most countries, but rather unique in Finland. Earlier the collected or required funds have been directed towards improving communication services. Another common concern from the telecommunications industry were the service coverage requirements. If they are set for the 800 MHz LTE coverage solely, the currently ongoing LTE deployments on other frequency ranges may slow down. The current mobile operators would prefer the coverage requirements for LTE combining the coverage of the operator on all frequencies. On the other hand, the draft version of the resolution brings the new entrants more equal chances in this respect. For a few years, the mobile operator frequencies have been given out in a balanced way, no matter if it happened through a beauty contest or an auction. The resolution draft is an exception. One operator will get more bandwidth than the others. This might increase competition and prices in auction, but it could also raise the motivation of a new entrant.
Although the discussion proceeds around LTE and mobile users, the first persons who experience the 800 MHz resolution are the radio microphone users. They have to change their equipment to work on the TV frequency areas. Unfortunate for the radio microphone users, the transfer is not that simple, because the microphones cannot be used on the same frequencies, which are used by the local terrestrial TV broadcasting. As a consequence, before using the microphone in a new location, the user should study tens of maps showing GE06 allotment plans, then he should go through a list of over 600 transmitters, and then look for any exceptions on the that location and frequency. For fixed installations made by professional audio engineers, the current guidance is feasible, but for other users the selection of the correct frequency becomes close to a random process.
LVM is looking for written comments for the resolution. In order to help the microphone users, the following actions could take place:
- There should be an easy to use online service to help the radiomicrophone users in the frequency selection
- It should be possible to utilize a part of the suggested 5.4 M€ for such a service
- The online or otherwise machine readable information about the higher priority transmitters should be on the level that such a service can be implemented.
A demo of a possible radiomicrophone service can be found in http://www.radiomikrofonit.fi/test/.