Wideband, Beamsteerable Connected Slotted-Patch Antenna Array for On-Package Millimeter Wave Applications

In this work, a long connected slot is cut out on a proximity-coupled patch antenna plane for the first time. The proposed connected slotted-patch antenna array (CSPAA) is designed, analyzed, fabricated, and measured for on-package millimeter-wave (mmWave) applications having wide beamsteering capabilities. Microstrip lines are used to excite the patch and the connected slot. The CSPAA is designed on a seven-layer vertical stack-up, making it suitable for on-package scenarios. The fabricated CSPAA has a measured bandwidth of 21.07% (centered at 28 GHz) and a measured realized gain of 9.51 dBi at broadside, yielding a total efficiency of 83%. The CSPAA demonstrates wide beamsteering capabilities up to ±390 with a compact form factor of 0.0881λ3 (1.52λ x 0.58λ x 0.1λ), where λ is the free-space wavelength at 28 GHz. A comprehensive comparison of the proposed CSPAA with the state-of-the-art shows that the proposed prototype has excellent bandwidth, gain, wide beamsteering capabilities, and a smaller form factor compared to previous solutions for mmWave on-package applications.