Extremely Low-Profile Dual-Band Antenna Based on Single-Layer Square Microstrip Patch for 5G Mobile Application
Yuehui Gao, Junlin Wang, Xin Wang, Zhanshuo Sun
Abstract
This letter presents an extremely low-profile dual-band antenna based on a single-layer square microstrip patch for 5G mobile application. The antenna has a height of only 0.8 mm (about 0.009 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">λ<sub>L</sub></i> at 3.45 GHz) and a footprint of 30 × 30 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> (0.345 × 0.345 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">λ<sub>L</sub></i> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ). The TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">10</sub> mode at around 3.56 GHz and the TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> mode at around 4.91 GHz for the antenna are obtained by etching a pair of symmetrical circular notches and a narrow rectangular slot on the square patch. The TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1/2,0</sub> mode at around 3.45 GHz and the TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1/2,1</sub> mode at around 4.83 GHz of the antenna are generated by further placing two two-order matrix-style shorting pins. The combination of the four modes can overcome the effect of insufficient bandwidth due to the very low profile, resulting in 3.4–3.6 GHz (partial 5G N78 band) and 4.79–4.94 GHz (partial 5G N79 band) dual-band operation. The measured results are also presented.