An Ultra-Wideband Study of Vegetation Impact on Upper Midband / FR3 Communication

TL;DR

This work addresses the under-explored impact of vegetation on FR3 communications by conducting ultra-wideband measurements from 6 to 18 GHz in an urban canyon. It introduces a simple vegetation-depth metric based on elliptical tree silhouettes and fits a frequency-dependent linear model L_veg(f, d_veg)=alpha(f) d_veg to quantify excess attenuation caused by foliage. Empirical results show excess vegetation loss increases with both vegetation depth and frequency, with alpha(f) ranging roughly from 0.86 to 2.48 dB/m across the studied bands. The findings provide a practical framework for foliage-aware link budgeting and network design in FR3, though notable scatter suggests broader measurements across vegetation types and geometries are needed to refine the model.

Abstract

Growing demand for high data rates is driving interest in the upper mid-band (FR 3) spectrum (6-24 GHz). While some propagation measurements exist in literature, the impact of vegetation on link performance remains under-explored. This study examines vegetation-induced losses in an urban scenario across 6-18 GHz. A simple method for calculating vegetation depth is introduced, along with a model that quantifies additional attenuation based on vegetation depth and frequency, divided into 1 GHz sub-bands. We see that excess vegetation loss increases with vegetation depth and higher frequencies. These findings provide insights for designing reliable, foliage-aware communication networks in FR 3.

Figures (4)

• Figure 1: Measurement site.
• Figure 2: Elliptical modeling of tree silhouettes for vegetation depth calculation.
• Figure 3: Sample PDPs between 6-7 GHz.
• Figure 4: Vegetation depth vs excess loss for different frequencies.