Low-Cost Aperture-Coupled 60-GHz-Phased Array Antenna Package With Compact Matching Network

Abstract

A low-cost multilayer antenna-in-package solution, using the standard printed-circuit-board (PCB) process, is proposed for the 60-GHz-phased array system. The design procedure focuses on overcoming the fabrication restrictions and realizing a low-cost, broadband, compact and reliable package solution. The multilayer stack-up structure consists of three laminates and two bondply layers, with which the antenna element, vertical quasi-coaxial via transition, antenna feedline, power, and low-speed interfaces are realized. An aperture-coupled patch antenna with a compact fan-shaped feeding network and a vertical quasi-coaxial via transition are proposed, fabricated, and measured. For the single antenna element, including the vertical quasi-coaxial via transition, the measured fractional impedance bandwidth ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\vert \text{S}11\vert &lt; -10$ </tex-math></inline-formula> dB) is 20.2%, and the measured peak gain is 6.9 dBi at 62 GHz. Based on the single antenna, a 16-element antenna package is realized in the dimension of 14 mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times14$ </tex-math></inline-formula> mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times0.925$ </tex-math></inline-formula> mm. Measurements show that each antenna element achieves a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\vert \text{S}11\vert $ </tex-math></inline-formula> less than −10 dB from 57.2 to 64.5 GHz, 4–7.5 dBi gain across all four IEEE 802.15.3c channels.