Stochastic Geometry-Based Modeling and Analysis of Citizens Broadband Radio Service System

In this paper, we model and analyze a cellular network that operates in the licensed band of the 3.5-GHz spectrum and consists of a licensed and an unlicensed operator. Using tools from stochastic geometry, we concretely characterize the performance of this spectrum sharing system. We model the locations of the licensed base stations (BSs) as a homogeneous Poisson point process with protection zones (PZs) around each BS. Since the unlicensed BSs cannot operate within the PZs, their locations are modeled as a Poisson hole process. In addition, we consider carrier sense multiple access with collision avoidance-type contention-based channel access mechanism for the unlicensed BSs. For this setup, we first derive an approximate expression and useful lower bounds for the medium access probability of the serving unlicensed operator BS. Furthermore, by efficiently handling the correlation in the interference powers induced due to correlation in the locations of the licensed and unlicensed BSs, we provide approximate expressions for the coverage probability of a typical user of each operator. Subsequently, we study the effect of different system parameters on area spectral efficiency of the network. To the best of our knowledge, this is the first attempt toward accurate modeling and analysis of a citizens broadband radio service system using tools from stochastic geometry.