Beam Switching for Intra- and Inter-Cell Mobility in mmWave Networks

This paper studies the impact of intra- and inter-cell mobility on mmWave networks with a specific focus on beam switching. The paper utilises a geometric model to partition the coverage area of a mmWave gNB cell into radial and angular sectors, thus accounting for the coverage footprints of planar antenna arrays with azimuth-tilt beam orientations (i.e., horizontal and vertical orientations). Using this model, intra-cell beam switching rate is derived analytically. We extrapolate the analysis using stochastic geometry to address inter-cell mobility and system-level beam switching. Our study establishes a relationship between the shape of the antenna array pattern and the beam switching rate. We validate our analysis via extensive Monte Carlo simulations and the results reveal the significant impact of the antenna configuration on beam switching rate. Even when the number of beams remains the same, the beam switching rate can almost double depending on how the antenna array elements are arranged.