Evaluation of spectrum access options for indoor mobile network deployment

The investments in indoor mobile networks are highly related to the spectrum availability and its associated authorization options. The aim of this paper is to discuss the differences in the spectrum demand taking into consideration both wide and local area network deployment requirements and the kind of actor that provides the indoor wireless access. The analysis covers different authorizations options namely licensed, unlicensed, licensed shared access (LSA) and secondary access. A quantitative approach is used to analyze the differences between macrocell and femtocell deployments focusing on deployment cost and spectrum demand. This is complemented by a qualitative study to explore and discuss the strategic business decisions of different actors in view of the available spectrum bands and spectrum authorization options. The main conclusions from this study are; spectrum has more value in macrocell deployment scenarios than in femtocell ones. More spectrum in macrocell deployment scenarios means that operators can deploy less number of new sites and exploit previous infrastructure investments. Femtocell networks are often coverage limited which allows for frequency re-use. As a consequence, the value of spectrum is not the same for mobile network operators (MNOs) and for local network operator (LNOs). MNOs are traditionally confined to macrocell deployment strategies which entail the exclusive usage of licensed bands. While, the use of licensed spectrum by LNOs may incur more cost than the cost of infrastructure deployment. This explains why the use of unlicensed bands is lucrative and viable for LNOs. Furthermore, the LSA scheme may or could soon become an enabler for LNO´s business due to the prevailing technical, regulation and policies developments.