Gains of Restricted Secondary Licensing in Millimeter Wave Cellular Systems

TL;DR

This paper models a mmWave cellular system with restricted secondary licensing, demonstrating that spectrum sharing can be economically beneficial and improve network performance, especially with narrow beams and dense networks.

Contribution

It introduces a stochastic geometry-based model for secondary licensing in mmWave systems, analyzing economic and technical feasibility of spectrum sharing.

Findings

Secondary licensing can be beneficial for original operators and authorities.

Spectrum sharing gains increase with narrower beams.

Network densification enhances sharing benefits.

Abstract

Sharing the spectrum among multiple operators seems promising in millimeter wave (mmWave) systems. One explanation is the highly directional transmission in mmWave, which reduces the interference caused by one network on the other networks sharing the same resources. In this paper, we model a mmWave cellular system where an operator that primarily owns an exclusive-use license of a certain band can sell a restricted secondary license of the same band to another operator. This secondary network has a restriction on the maximum interference it can cause to the original network. Using stochastic geometry, we derive expressions for the coverage and rate of both networks, and establish the feasibility of secondary licensing in licensed mmWave bands. To explain economic trade-offs, we consider a revenue-pricing model for both operators in the presence of a central licensing authority. Our results show that the original operator and central network authority can benefit from secondary licensing when the maximum interference threshold is properly adjusted. This means that the original operator and central licensing authority have an incentive to permit a secondary network to restrictively share the spectrum. Our results also illustrate that the spectrum sharing gains increase with narrow beams and when the network densifies.