# Exploring Carbon-Fiber UAV Structures as Communication Antennas for Adaptive Relay Applications
## 3 Results
### Radiation Pattern in Azimuth and Elevation Results  
As a result of the experiment, radiation pattern graphs in the azimuth plane were plotted, as shown in Figure 15.  
Figure 15 depicts the 2D azimuthal field distribution of Antenna A (blue trace) and Antenna B (red trace) in polar coordinates, overlaid with their respective -3 dB contours (shown as lighter-shaded lines in matching colors). From this representation, the half-power aperture angle in the horizontal plane can be read directly. Both antennas maintain field levels within 3 dB of their peaks over essentially the full 360\({}^{\circ}\) sweep, confirming quasi-ommidrectional performance. Projecting each -3 dB contour onto a circle of radius R yields the effective aperture radius within which the antenna radiates or receives signals optimally. In practical terms, this large aperture radius ensures uniform coverage around a UAV, with received power oscillating between -50 dB and -65 dB (mean \(\approx\) -58 dB). Minor asymmetries--most pronounced for Antenna A (blue) between 270\({}^{\circ}\) and 330\({}^{\circ}\)--and the slightly smoother red contour of Antenna B may be attributed to small fabrication tolerances or reflections in the test environment, but in all cases, the radiation remains well within the half-power boundary.  
Figure 16 presents the radiation pattern in elevation obtained from the experimental measurements.  
The elevation-plane field distribution of the same two antennas, again with Antenna A in blue and Antenna B in red, each accompanied by its -3 dB beamwidth contour in a corresponding lighter hue. Both antennas exhibit two symmetric main lobes centered around the horizontal (0\(\simeq\)90\({}^{\circ}\)), with a -3 dB aperture angle of approximately 40-50\({}^{\circ}\) that defines their vertical half-power coverage. Antenna B's red beamwidth contour extends marginally farther--indicating slightly higher gain between 30\({}^{\circ}\) and 70\({}^{\circ}\) elevation--whereas Antenna A's blue contour is narrower yet more uniform, reflecting a tighter control of its radiating  
Figure 15: Radiation pattern in Azimuth.  
aperture. Near the end-fire directions (\(\theta\)\(\simeq\)0\({}^{\circ}\) and 180\({}^{\circ}\)), both contours collapse toward the center, illustrating the expected nulls of a vertically oriented radiator.  
The general shape of the graph is typical for vertically mounted antennas, where the electric field is weak along the main axis and stronger around it. The differences between the two antennas may reflect minor construction or alignment variations. Overall, the graph provides a clear representation of the elevation performance of the tested antennas and is useful for determining the optimal mounting angle in practical applications.  
By emphasizing the colored traces and their -3 dB contours, this analysis quantifies each antenna's spatial coverage: the broad blue and red apertures in azimuth confirm nearly uniform horizontal radiation, while the distinct colored beamwidths in elevation reveal the focused lobes and nulls that will dictate optimal mounting angles and link-budget calculations in UAV deployments.