The main players in the European spectrum regulatory framework are the Euro- pean Commission (EC), and the Electronic Communications Committee (ECC), of the European Conference of Postal and Telecommunications Administrations (CEPT). The EC makes binding decisions on frequency use for EU member countries. The EC has made large investments in CR research.
The Radio Spectrum Policy Group (RSPG) of the EC is a high-level advisory group that assists the EC in the development of radio spectrum policy. The RSPG adopts opinions, position papers, and reports, as well as issuing state- ments aimed at assisting and advising the Commission at strategic level on radio spectrum policy issues, coordination of policy approaches, and harmonized con- ditions with regard to the availability and efficient use of radio spectrum neces- sary for the establishment and functioning of the internal market. The RSPG develops opinions on spectrum topics, e.g., digital dividend, collective use of spectrum (CUS), spectrum trading, etc. For example, CUS allows an undeter- mined number of independent users and/or devices to access spectrum in the
same range of frequencies at the same time and in a particular geographic area under a well-defined set of conditions. In February 2010, the RSPG also finished its report on cognitive technologies (RSPG 2010). The Radio Spectrum Commit- tee (RSC) of the EC assists the EC in the development and adoption of technical implementing measures aimed at ensuring harmonized conditions for the avail- ability and efficient use of radio spectrum, as well as the availability of informa- tion related to the use of radio spectrum.
National regulatory authorities have sole responsibility for managing frequency use in their own countries. In Finland, the testing of CRSs is already possible in the 470–790 MHz band if they do not cause interference to other radio traffic.
CR-related activities are on-going in different groups of the ECC. The Con- ference Preparatory Group (CPG) has been preparing for WRC. The CPG Pro- ject Team A PTA has prepared the draft CEPT brief on AI1.19 of WRC-12 on general regulatory and technical issues. The CEPT brief to the agenda item was finished in June 2010. The Working Group Frequency Management (WG FM) is responsible for coordinating the work on CRS issues. A correspondence group (CG CRS) was created to handle this. The Working Group Regulatory Affairs (WG RA) has created an ad-hoc group to identify possible WG RA-related work items on CR, including PT RA1, which looks into associated enforcement issues.
The Working Group Spectrum Engineering (WG SE) has established the group SE43 Cognitive Radio Systems – White Spaces (470–790 MHz). SE43 defines technical and operational requirements for the operation of cognitive radio systems in the white spaces of the ultra high frequency (UHF) broadcasting band (470–790 MHz) to ensure the protection of incumbent radio services/systems and investigate the consequential amount of spectrum potentially available as “white space.” SE43 can also provide technical assistance on further issues related to white spaces and CRSs. SE43 published an ECC Draft Report “Technical and operational requirements for the operation of cognitive radio systems in the ‘white spaces’ of the frequency band 470–790 MHz” in January 2011 (ECC 2011).
In Europe, there has been recent activity in the “digital dividend,” which de- notes the spectrum resulting from the switchover from analogue to digital TV in the bands 470–862 MHz. The activities in the digital dividend are closely related to CR, as the white spaces in TV bands have been considered a major applica- tion scenario and driving force for CR research.
According to the CEPT definition, white space is part of the spectrum which is available for a radiocommunication application (service, system) at a given time in a given geographical area on a non-interfering/non-protected basis with
regard to primary services and other services with a higher priority on a national basis (CEPT 2008).
CEPT Report 24 (CEPT 2008), published in July 2008, gives a preliminary assessment of fitting new services into TV white spaces. In Europe, white spaces in the TV bands (i.e., 470–862 MHz) are 8 MHz segments of spectrum between active TV stations in a given area in a given time. The available spectrum from the digital dividend is likely to be more limited in Europe than the US, and far less spectrum will be available than previously with analogue TV. Moreover, the band 790–862 MHz was identified for IMT at WRC-07, and the re-arrangement of this band in Europe will take a long time and cause high uncertainty over the extent of spectrum availability.
The major challenge in applying TV white spaces for communications is that program making and special event (PMSE) services already operate on the TV spectrum on an interleaved basis (e.g., wireless microphones, in-ear monitors) normally on a “tuning range” basis. PMSE services use white space spectrum intensively in certain areas at certain times. Their controlled employment is effi- cient in spectrum use.
Any new application that is proposed to exploit the TV white spaces is sup- posed to use CR techniques in order to detect the presence not only of TV sig- nals but also of PMSE users, which is challenging. In addition, an important remark is that any new white space application should be used on a non-
protected, non-interfering basis, which must be taken into account in CR re-
search. The proposed applications should not only be compatible with other services on the TV bands (e.g., current TV and PMSE equipment) but also with the possibility of evolution of TV planning and technology.
Before any sharing scheme could be applied to the TV bands, it should be carefully assessed and confirmed, including testing. CEPT remarks that it is too early to judge the final capabilities of CR technology, and further studies are needed. The feasibility of cognitive sharing schemes has not yet been demon- strated conclusively. The requirements for CRs should be looked into further, including, for example, interference to TV and PMSE services and the coexistence of different categories of license-exempt usage (e.g., asymmetric power needs).