Undergraduate Colloquium

Daniil Shaposhnikov: We explore optimization techniques and antenna synthesis strategies for real time low-frequency beamforming and interference nulling with an airborne antenna array. The focus is on utilizing the airborne network as a relay to transmit around attenuating obstacles, such as forests, with the goal of outperforming a direct link. Unlike traditional antenna design, where alignment accuracy of elements and mechanical tolerances are carefully accounted for, this airborne network is naturally sensitive to tilting and position errors due to environmental factors so we must account for this in our optimization.

Macy Mosier: We present an iterative approach for generating a focused beam, or a beam with a null in the far-field of an antenna grid arranged in a double cross formation. Building on the work of Egarguin[1], our method begins with a 2D far-field approximation to steer the antenna grid toward a desired direction. The far-field pattern is then normalized, and for each sidelobe exceeding a predefined threshold, currents are calculated for each dipole to cancel the sidelobe. This process is repeated until all sidelobes fall below the threshold. Additionally, a null can be introduced by performing the sidelobe cancellation process on all elements except the center, and then determining the center’s current to eliminate the far-field pattern in the null direction. The result is a focused beam with optional null placement and sidelobes that remain below the established threshold.

[1] Neil J. Egarguin, David R. Jackson, Daniel Onofrei, and Pratik Deb, Adaptive Beamforming with a Double-Cross Array of Dipoles on a Drone, 2024 IEEE Texas Symposium on Wireless and Microwave Circuits and Systems (WMCS)