Coverage and Rate Analysis for Millimeter Wave Cellular Networks
Tianyang Bai and Robert W. Heath, Jr.
To appear in IEEE Trans. Wireless Commun., 2014.
Millimeter wave (mmWave) holds promise as a carrier frequency for fifth generation cellular networks.
Because mmWave signals are sensitive to blockage, prior microwave cellular network models do
not apply to analyze mmWave cellular networks directly. Leveraging concepts from stochastic geometry,
this paper proposes a general framework to evaluate the coverage and rate performance in mmWave
cellular networks. Using a distance-dependent line-of-site (LOS) probability function, the locations of
the LOS and non-LOS base stations are modeled as two independent non-homogeneous Poisson point
processes, to which different path loss laws are applied. Based on the proposed framework, expressions
for the signal-to-noise-and-interference ratio (SINR) and rate coverage probability are derived. The
mmWave coverage and rate performance are examined as a function of the antenna geometry and
base station density. The case of dense networks are further analyzed by applying a simplified system
model, in which the LOS region of a user is approximated as a fixed LOS ball. The results show that
dense mmWave networks can achieve comparable coverage and much higher data rates than microwave
systems, despite the presence of blockages. The results suggest that the cell size to achieve best optimal
SINR scales with the average size of the area unblocked by blockages to a user.