Dual-polarization 1-Bit/Quasi-2-Bit Low-Cost Programmable Metasurface with Control Circuit Merged

We propose a low-cost programmable metasurface (PM) with distinct advantages of being 1-bit or quasi-2-bit, featuring dual polarization, and requiring fewer I/O pins. This design merges the control circuit and the microwave structure layout on a thin, single-layer printed circuit board (PCB). To achieve this, we transform the aperiodic control circuit into a periodic circuit by loading D flip-flops, which is further simplified by loading controlled current sources. Based on the layout of the bias lines, a capacitive slot is added to form the microwave structure. Two PIN diodes are orthogonally surface-mounted to achieve dual-polarization characteristics. In unit arraying, D flip-flops are staggered to reduce I/O pins usage. The design can be easily extended to quasi-2-bit by stacking the PCBs. A 16×16 1-bit PM is simulated, fabricated, and measured to verify this design. The simulation includes functions such as generating high-gain beams, multi-beams, and electromagnetic waves carrying orbital angular momentum. The far-field patterns exhibited a ±60° scanning range, achieving a maximum aperture efficiency of 25%. This design introduces a simple, cost-effective, adjustable operating frequency, dual-polarization, 1-bit, or quasi-2-bit PM, with potential applications in communication, imaging, and sensing scenarios.