Analysis of Blockage Effects on Roadside Relay-Assisted mmWave Backhaul Networks

mmWave communication is a highly promising technology for 5G wireless backhaul. However, network performance is hard to predict due to the sensitivity of mmWave signals to blockages. In this paper, we propose an analytical framework to incorporate blockage effects and evaluate blockage robustness within a previously proposed interference-free topology for roadside relay-assisted mmWave backhaul. Through stochastic geometric analysis, the blockage probabilities for four types of blockages identified in prior work are derived as a function of the topology parameters and obstacle density. Analysis of the effect of topology parameters on blockage probability yields insight that leads to a modified topology, which maintains the desirable interference-free property but has better blockage robustness than the original topology. Simulation results demonstrate that the modified topology can maintain very high throughput and has significantly improved robustness as compared to the original topology, while using the same number of relays.