US Patent 11973274 Single-switch-per-bit topology for reconfigurable reflective surfaces

A single-switch-per-bit topology for reconfigurable reflective surfaces (RRSs) is provided. Novel multi-bit unit-cell configurations are presented for radio-frequency (RF) RRSs with improved radiation efficiency and compact designs. Embodiments described herein realize a multi-bit RRS using an antenna array with multiple integrated switches at the ports of every antenna element (e.g., one at each port, providing one control bit per switch). By manipulating the states of the switches, the impinging waves on the surface are modulated, leading to beamforming in the desired direction. Some embodiments utilize a single switch-per-bit topology integrating single-pole-single-throw (SPST) switches (e.g., PIN diodes) into the unit-cell design, achieving up to 4 bits of phase quantization with only 4 switches. The exhibited radiation efficiency of the multi-bit RRS is significantly improved compared to lower bit configurations.