Department of Electrical Engineering, Shiraz Branch, Islamic Azad University, Shiraz, Iran.
School of Electrical Engineering, Iran University of Science and Technology, Tehran, Iran.
Sci Rep. 2021 Oct 28;11(1):21265. doi: 10.1038/s41598-021-00679-8.
In this paper three different multi stub antenna arrays at 27-29.5 GHz are designed. The proposed antenna arrays consist of eight single elements. The structure of feeding parts is the same but the radiation elements are different. The feeding network for array is an eight way Wilkinson power divider (WPD). To guarantee the simulation results, one of the proposed structures is fabricated and measured (namely the characteristics of S, E-, and H-plane patterns) which shows acceptable consistency with measurement results. The simulation results by CST and HFSS show reasonable agreement for reflection coefficient and radiation patterns in the E- and H- planes. The overall size of the proposed antenna in maximum case is 29.5 mm × 52 mm × 0.38 mm (2.8 [Formula: see text]× 4.86[Formula: see text] × 0.036[Formula: see text]). Moreover, for Specific Absorption Rate (SAR) estimation, a three-layer spherical human head model (skin, skull, and the brain) is placed next to the arrays as the exposure source. The simulation results show that the performance of proposed antennas as low-SAR sources makes them ideal candidates for the safe usage and lack of impact of millimeter waves (mmW) on the human health. In all three cases of SAR simulations the value of SAR and SAR are below the standard limitations.
本文设计了三种工作在 27-29.5GHz 的多短截线天线阵列。所提出的天线阵列由八个单兀组成。馈电部分的结构相同，而辐射单元不同。阵列的馈电网络是一个八路威尔金森功率分配器（WPD）。为了保证仿真结果的准确性，对其中一种结构进行了制作和测量（即 S、E-和 H-平面方向图的特性），结果表明与测量结果具有良好的一致性。CST 和 HFSS 的仿真结果在 E-和 H-平面的反射系数和辐射方向图方面具有较好的一致性。在最大尺寸的情况下，所提出的天线整体尺寸为 29.5mm×52mm×0.38mm（2.8λ×4.86λ×0.036λ）。此外，为了进行比吸收率（SAR）评估，将一个三层球形人体头部模型（皮肤、颅骨和大脑）放置在阵列旁边作为辐射源。仿真结果表明，所提出的天线作为低 SAR 源的性能使得它们成为安全使用毫米波（mmW）并避免其对人体健康产生影响的理想候选者。在 SAR 仿真的所有三种情况下，SAR 和 SAR 的值均低于标准限制。
