Next generation of radio spectrum management: Licensed shared access for 5G

Journal article, 2017

Deployment of 5th generation (5G) mobile communication technology is setting the stage for the next generation of radio spectrum management. New spectrum sharing arrangements have been identified as effective ways to satisfy emerging connectivity needs. In particular, the so-called Licensed Shared Access (LSA) regime has been given prominence in the European Union (EU) to facilitate access to additional spectrum necessary to meet the exponential growth of mobile data traffic. Under the LSA regime, already occupied, but underutilised spectrum would be shared, on a licensed-basis, between incumbents and mobile operators, under agreed frequency, location and time sharing conditions. A similar system has been proposed in the United States (US), called Spectrum Access System (SAS). In this context, the purpose of this paper is two-fold: firstly, to assess the novelty of the LSA regime with respect to existing spectrum sharing arrangements in the EU and, secondly, to identify the main differences between the LSA and the SAS regimes. Policy documents, academic papers, position papers and analysis reports are scrutinised to gather information on technical and regulatory aspects of existing and emerging spectrum sharing regimes. This paper concludes that the novelty of the LSA regime is found in the possibility for mobile operators to access additional spectrum below 6 GHz (GHz) with the regulatory certainty required to invest in 5G. Implementing other spectrum sharing regimes to access sub-6 GHz spectrum would not guarantee mobile operators protection from harmful interference and predictable Quality of Service (QoS). The comparison between the LSA and the SAS approaches suggests that the LSA regime can be implemented quicker and with less effort than the SAS regime, because of its lower level of technical complexity. Nevertheless, the LSA regime is expected to be overtaken by the SAS regime in the long term, as technology advances. The SAS regime would allow more users to coexist in the same spectrum bands thanks to spectrum sensing techniques.