A compact high-gain patch antenna using stacked rings in LTCC technology

A compact high-gain patch antenna using stacked rings based on low-temperature co-fired ceramic (LTCC) multilayer technology is proposed in this paper. Three metal stacked rings are employed to surround the patch antenna, acting as directors to guide the electromagnetic wave radiating toward broadside and, hence, improve the antenna's gain. Also, three ground planes are connected by metallic vias to form a cavity-backed structure, which suppresses the outward propagating diffraction wave and contributes to the improvement of the antenna's gain either. The fabricated antenna achieves a high gain of 8.1dBi at 36.7GHz including the loss of the feeding parts and radio-frequency (RF) probe, and the gain is relatively stable within the bandwidth. Furthermore, the antenna only occupies a compact size of mm3 which is much smaller than most of the other high-gain patch antennas on LTCC.