Programmable Metasurface Based on Substrate-Integrated Waveguide for Compact Dynamic-Pattern Antenna

A programmable metasurface based on a substrate-integrated waveguide (SIW) is proposed to realize a dynamic-pattern antenna, which satisfies the critical needs of low cost, ease of manufacturing, and easy integration with planar circuits in real-life applications. The proposed metasurface consists of 16 elements of complementary electric-LC resonators that are etched on the top layer of the SIW. Each element is installed with two p-i-n diodes to reach different states, which are controlled by a dc bias signal through a via from the backside of a printed circuit board (PCB). Both the element parameters and their positions along the SIW are carefully designed for better performance as an antenna. By utilizing different diodes' tuning schemes, the phase difference between the radiating elements can be dynamically changed, thereby realizing antenna-pattern generation and reconfiguration in real time. Experimental results show that the proposed metasurface can generate not only narrow-to-wide steerable directive beams but also complex multibeam patterns by programming different digital codes. A prototype is fabricated with low-cost PCBs, and good agreements among the simulated and measured patterns are observed. The proposed SIW-based metasurface has a great potential for applications in dynamic-pattern-enhanced microwave imaging, radar, and communication systems.