  We study the behaviour of WiFi and 5G cellular networks as they exploit the
recently unlocked 6 GHz spectrum for unlicensed access, while conforming to the
constraints imposed by the incumbent users. We use tools from stochastic
geometry to derive the theoretical performance metrics for users of each radio
access technology, which helps us in capturing the aggregate behaviour of the
network in a snapshot. We propose a framework where the portions of cellular
and WiFi networks are grouped together to form entities. These entities
interact to satisfy their Quality of Service demands, by playing a
non-cooperative game. The action of an entity corresponds to the fraction of
its network elements (WiFi access point and cellular base stations) operating
in the 6 GHz band. Due to the decentralized nature of the entities, we find the
Nash equilibrium using distributed Best Response Algorithm, where each entity
takes actions without any centralized scheduling. The results demonstrate how
the system parameters affect the performance of a network at equilibrium and
highlight the throughput gains of the networks as a result of using the 6 GHz
bands, which offer considerably larger bandwidths. The proposed framework is
flexible and can be used to model a variety of scenarios for feasibility and
performance assessment of the networks involved.
