Full‐Space Triple‐Channel Circularly‐Polarized Metasurface with Arbitrary Amplitude Allocation and Independent Phase Control

Abstract Flexible manipulations to amplitudes and phases of multi‐channel circularly polarized (CP) waves using a single metasurface have attracted significant attention in recent years. Here, a full‐space triple‐channel circularly‐polarized metasurface (FSTCM) is proposed to achieve arbitrary amplitude allocations and independent phase controls. The FSTCM is composed of receiver‐transmitter integrated meta‐atoms, in which a phase‐delay line is introduced between the receiving and transmitting patches. By adjusting the impedance matching characteristics of the receiver and the polarization characteristics of the transmitter, the amplitudes of co‐polarized reflection, co‐polarized transmission, and cross‐polarized transmission under a CP incident wave can be arbitrarily allocated, while their phases can be independently controlled by combining the geometric phases of receiver and transmitter with the propagation phase of the phase‐delay line. As experimental demonstrations, a three‐beam transmit‐reflect‐array antenna (TRA) with arbitrary energy allocation and different radiation angles, and a bidirectional TRA with low sidelobe levels (SLLs) for both reflection and transmission beams is designed, fabricated, and measured, respectively. The simulated and measured results of two TRAs agree very well with theoretical predictions, showing that the proposed FSTCM can provide greater degrees of freedom for controlling CP waves and has good performance.