Inter-Operator Base Station Coordination in Spectrum-Shared Millimeter Wave Cellular Networks

TL;DR

This paper analyzes spectrum sharing in millimeter wave cellular networks, showing how inter-operator base station coordination improves coverage especially in dense, high-power, and wide-beam scenarios.

Contribution

It models the rate coverage in spectrum-shared mmWave networks with inter-operator coordination, deriving new analytical expressions and validating them with simulations.

Findings

Coordination enhances coverage in dense, high-power networks.

Wide beamwidths (30° or more) benefit more from coordination.

Analytical model accurately predicts coverage probabilities.

Abstract

We characterize the rate coverage distribution for a spectrum-shared millimeter wave downlink cellular network. Each of multiple cellular operators owns separate mmWave bandwidth, but shares the spectrum amongst each other while using dynamic inter-operator base station (BS) coordination to suppress the resulting cross-operator interference. We model the BS locations of each operator as mutually independent Poisson point processes, and derive the probability density function (PDF) of the K-th strongest link power, incorporating both line-of-sight and non line-of-sight states. Leveraging the obtained PDF, we derive the rate coverage expression as a function of system parameters such as the BS density, transmit power, bandwidth, and coordination set size. We verify the analysis with extensive simulation results. A major finding is that inter-operator BS coordination is useful in spectrum sharing (i) with dense and high power operators and (ii) with fairly wide beams, e.g., 30 or higher.