# Exploring Carbon-Fiber UAV Structures as Communication Antennas for Adaptive Relay Applications
## 4 Discussion
Distance (Bottom-Right Plot): This plot compares the received power (dBm) at different distances (0.5 m and 2.0 m) for the theoretical and measured cases. The measured values (blue circles) show a slight deviation from the theoretical values (dashed line with squares), with error bars representing small inconsistencies due to environmental effects such as reflections or near-field distortions. As expected, the received power decreases as distance increases, following the inverse-square law, but real-world factors like multipath interference introduce slight variations. Overall, while the theoretical models provided a strong foundation for understanding antenna behavior, the practical measurements emphasized the necessity of empirical validation. The results confirm that a UAV copter frame can function as a directional antenna, with performance variations largely influenced by environmental and structural factors. Future optimizations, such as impedance tuning and material refinement, could further enhance signal transmission efficiency. In relation to broader developments in the field, the present study complements the findings reported in the article [12]. While that article presents a comprehensive survey of UAV-based antenna measurements--focusing on far-field and near-field campaigns using various airborne platforms and frequencies ranging from 20 MHz to 24 GHz--its emphasis lies in utilizing UAVs as flexible platforms for evaluating external antennas. These campaigns typically involved UAVs equipped with dedicated probes (e.g., log-periodic dipole arrays, horn antennas, monopoles) flying in circular or vertical trajectories to reconstruct 3D radiation patterns or validate propagation models such as two-ray or knife-edge diffraction. By contrast, the current work explores the integration of carbon-fiber monopole antennas directly into the UAV frame, shifting the perspective from the UAV as a measurement tool to the UAV as a radiating structure. Rather than externally mounted probes, the carbon-fiber airframe itself serves as the radiating element. This study evaluates core antenna metrics--center frequency, S\({}_{11}\), VSWR, gain, and radiation patterns--while also validating performance through empirical measurements under realistic propagation conditions, including small-scale fading, polarization misalignment, and environmental obstructions. Notably, while the review article highlights phenomena such as propeller-induced Doppler effects and UAV body interactions as potential challenges, the present study takes a step further by quantifying the impact of structural materials (carbon fiber) and environmental interactions on antenna behavior. The inclusion of Rician fading analysis, maximum-likelihood fitting of envelope distributions, and link budget verification over different distances adds depth to the practical characterization of embedded antennas. In summary, the reviewed article demonstrates the versatility of UAVs in antenna and propagation research, especially in large-scale field measurements, whereas the carbon-fiber antenna study advances the concept of structurally embedded, lightweight antenna systems for UAV communications. Together, these works illustrate two complementary directions: using UAVs to characterize antennas in complex environments and embedding antennas within UAVs for efficient, stealthy, and space-saving communication system design.