Figure 1
From: Multiplexed Millimeter Wave Communication with Dual Orbital Angular Momentum (OAM) Mode Antennas
The ring resonator. (a) The waveguide ring resonator with two feeding ports (EPA and EPB). The angle between two feeding ports is γ. The circular slot is in the narrow wall of the resonator. (b) The traveling-wave electric field distribution in the resonator and the radiation field from the slot.
