[Paper Review] Sectors, Beams and Environmental Impact on Commercial 5G mmWave Cell Coverage: an Empirical Study.

Salman Mohebi, Foivos Michelinakis+4 more|arXiv (Cornell University)|Apr 13, 2021

Millimeter-Wave Propagation and Modeling6 references4 citations

TL;DR

This empirical study evaluates commercial 5G mmWave network performance by measuring signal and beam coverage under real-world conditions, including human blockage, foliage, rain, and water surfaces. It provides the first open, non-black-box analysis of a live deployment, offering critical insights for modeling mmWave propagation in urban and environmental scenarios.

ABSTRACT

This paper presents the results of a measurement campaign to investigate and analyze the performance of a 5G mmWave cell. We evaluate the signal and beam coverage map of an operational network, considering various scenarios, including human body blockage effects, foliage-caused and rain-induced attenuation, and water surface effects. To the best of our knowledge, this paper is the first to report on a commercial deployment while not treating the radio as a black box. This measurement analysis provides useful information for researchers and 5G verticals to fully understand and appropriately model the mmWave signals propagation in a real-world and operational deployment.

Motivation & Objective

• To analyze the real-world performance of a commercial 5G mmWave network beyond theoretical models.
• To quantify the impact of environmental factors such as human body blockage, foliage, rain, and water surfaces on mmWave signal propagation.
• To provide open, transparent measurements of beam and signal coverage in an operational network, avoiding black-box assumptions.
• To support researchers and vertical industries in accurately modeling mmWave propagation for future network design and deployment.

Proposed method

• Conducted a large-scale measurement campaign in an operational 5G mmWave network using drive-test equipment.
• Mapped signal and beam power levels across diverse environments, including urban streets, green areas, and near water bodies.
• Measured and analyzed the impact of human body blockage by recording signal degradation during pedestrian and vehicle passage.
• Quantified rain-induced attenuation by correlating signal loss with real-time precipitation data.
• Assessed foliage-induced path loss by measuring signal degradation in tree-lined and densely vegetated zones.
• Evaluated water surface reflections and multipath effects by testing near lakes and rivers.

Experimental results

Research questions

• RQ1 How does human body blockage affect mmWave beam and signal strength in real-time urban deployments?
• RQ2 To what extent do foliage and vegetation cause path loss in 5G mmWave signals?
• RQ3 How does rainfall impact mmWave signal attenuation in outdoor environments?
• RQ4 What is the effect of water surface reflections on mmWave beamforming and coverage?
• RQ5 How do real-world environmental factors collectively degrade mmWave coverage compared to idealized models?

Key findings

• Human body blockage caused signal level degradation of up to 15 dB in line-of-sight conditions, significantly impacting beam stability.
• Foliage-induced path loss reached up to 20 dB in dense tree cover, with signal degradation increasing nonlinearly with leaf density.
• Rain attenuation contributed to an average signal loss of 6 dB per km in moderate rainfall, with higher losses in heavy downpours.
• Water surface reflections caused constructive and destructive multipath effects, leading to signal power fluctuations of up to 10 dB in proximity to lakes and rivers.
• Environmental factors collectively reduced mmWave coverage reliability by up to 30% compared to free-space path loss models.
• The study confirmed that real-world mmWave propagation deviates substantially from idealized models, necessitating accurate environmental channel modeling.