Multi-Objective Optimization and Design of High-Efficiency OAM Antenna Based on Single-Sideband Time Modulation

In this paper, a design of circular single-sideband (SSB) time-modulated array (TMA) for generating orbital angular momentum (OAM) beams is proposed. It increases signal bandwidth significantly compared with conventional TMAs for generating vortex waves. Theoretical analysis and simulated results of the proposed SSB TMA modulated by the optimized four-step pulse are reported. Higher harmonic efficiency and total efficiency (98.73% and 64.15%) are achieved simultaneously. And mode 1, 2, and 3 OAM beams with mode purity up to 97.3%, 97.2%, and 79.6% are generated at the first positive harmonic frequency.