On the expiration date of spectrum sharing in mobile cellular networks

Driven by a combination of flat lining revenues and an explosive growth in the mobile data traffic and hence the need for network resources, mobile operators consider infrastructure-and spectrum sharing as a means to reduce operational costs. We develop and apply an assessment approach to quantify the benefits associated with spectrum sharing in an infrastructure-shared environment, and estimate the evolution of the derived `spectrum sharing dividend' as traffic loads, radio access technologies, spectrum availability and performance targets change over time. The obtained insights can assist operators and regulators in their assessment of the merit of spectrum sharing. Analysis shows that operators with loads that peak at different times continue to benefit significantly by sharing spectrum, despite the diminishing `trunking gains' of spectrum sharing as individual operator loads and capacities increase over time.