Wideband Single-Layer D-Band Patch Antenna with Parasitic Elements and Superstrate Loading

This paper proposes a D-band patch antenna featuring four parasitic elements and a loaded superstrate layer. Inspired by a previous parasitic patch antenna design, the new structure is synthesized from scratch using characteristic mode analysis. The new design features different operating principles that enable low-cost single-layer fabrication on PCB HDI technology, while retaining wideband operation and high gain performance of the previous design. With the coupling between the active and parasitic patches limiting the bandwidth and radiation performance, a superstrate is added to improve the parasitic coupling and hence allowing a larger gap between the patches that fulfills fabrication requirements. The simulated results demonstrate that the antenna achieves 20.2% 10 dB impedance bandwidth and 9 dBi peak gain. The low cost and high performance make the design suitable for 6G applications.