Energy Efficiency in Relay-Assisted mmWave Cellular Networks

TL;DR

This paper analyzes the energy efficiency of relay-assisted mmWave cellular networks considering directional beamforming, LOS/NLOS path loss, and practical alignment errors, providing insights into system parameter impacts.

Contribution

It introduces a stochastic geometry-based model for energy efficiency in relay-assisted mmWave networks, incorporating beamforming errors and diverse system parameters for the first time.

Findings

Energy efficiency depends on BS and relay densities.

Beamforming alignment errors reduce energy efficiency.

LOS interference range significantly impacts performance.

Abstract

In this paper, energy efficiency of relay-assisted millimeter wave (mmWave) cellular networks with Poisson Point Process (PPP) distributed base stations (BSs) and relay stations (RSs) is analyzed using tools from stochastic geometry. The distinguishing features of mmWave communications such as directional beamforming and having different path loss laws for line-of-sight (LOS) and non-line-of-sight (NLOS) links are incorporated into the energy efficiency analysis. Following the description of the system model for mmWave cellular networks, coverage probabilities are computed for each link. Subsequently, average power consumption of BSs and RSs are modeled and energy efficiency is determined in terms of system parameters. Energy efficiency in the presence of beamforming alignment errors is also investigated to get insight on the performance in practical scenarios. Finally, the impact of BS and RS densities, antenna gains, main lobe beam widths, LOS interference range, and alignment errors on the energy efficiency is analyzed via numerical results.