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)