Miniaturized Dual-Band Broadside/Endfire Antenna-in-Package for 5G Smartphone

Abstract

This article proposes a miniaturized antenna in package (AiP) for 5G millimeter-wave smartphone that incorporates broadside and endfire arrays and supports a dual band covering 28 and 39 GHz. This article demonstrates that the proposed AiP is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$5.8\,\,\text {mm} \times 19\,\,\text {mm} \times 1.122$ </tex-math></inline-formula> mm. It is believed that this is the smallest 5G AiP that can support a 10 dBi antenna gain, a 10 dB return-loss bandwidth of 3 GHz, and more than 10 dB isolation for both broadside and endfire arrays. AiP consists of a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1\times 4$ </tex-math></inline-formula> patch antenna array for broadside radiation and a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1 \times 4$ </tex-math></inline-formula> dipole antenna array for endfire radiation. To miniaturize the patch antenna elements, a multilayer Reactive Impedance Surface (RIS) is embedded between the patch layer and the ground plane. This multilayer RIS idea greatly fits in 5G PCB-stack-up antennas where each stack-up layer essentially requires certain portion of copper area. For the endfire array antenna, miniaturization with bandwidth improvement is achieved by modifying the vertically bent folded dipole antenna (VBFDA) and adding a tightly coupled T-shape side via wall. The AiP achieves a 10 dB return-loss bandwidth of 26.22 to 29.57 GHz and 35.18 to 41.00 GHz for Multilayer RIS Patch Antenna (MLRPA), and 26.40 to 29.74 GHz and 36.65 to 40.72 GHz for VBFDA. The antenna gain is 11.6 dBi for MLRPA and 10.0 dBi for VBFDA.

Topics & Concepts