A compact CPW-fed band-notched UWB-MIMO flexible antenna for WBAN application

Abstract

A compact coplanar waveguide (CPW)-fed band-notched ultra-wideband (UWB) multiple-input multiple-output (MIMO) flexible antenna on liquid crystal polymer (LCP) substrate is designed. It is composed of two orthogonal elements, tampered feeder and asymmetric ground plate. To improve the port isolation (S₂₁), an inverted F-shaped branch is added. The measurement results demonstrate that the antenna has achieved impedance bandwidths (S₁₁< −10 dB) of 890 MHz (2.4–11.3 GHz) except one rejected band of 3.1–4.3 GHz, and the port isolation is higher than 23 dB. The influence of human body and bending have also been experimented. The results show that the designed antenna has satisfactory bandwidth, high isolation, sound gain in working bands, the characteristics of flexibility and low specific absorption ratio (SAR) values, which indicate the excellent application in the WBAN systems.

KEYWORDS:

• CPW (coplanar waveguide)
• LCP (liquid crystal polymer)
• MIMO antenna
• flexible
• band-notched
• tampered feeder
• asymmetrical

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China under grant number 61371022.

Notes on contributors

Chengzhu Du

Chengzhu Du was born in Haikou, Hainan Province, China. She received the B.S. degree from the Xidian University, M.S. degree from Nanjing University of Posts and Telecommunications and PhD degree from Shanghai University, in 1995, 2003 and 2012, respectively, all in electromagnetic wave and microwave technology. She is currently an associate Professor of Shanghai University of Electric Power. Her research interests include flexible antenna and textile antenna, multiband and wideband antennas, and MIMO technologies.

Gaoya Jin

Gaoya Jin was born in Shijiazhuang, Hebei Province, China in 1995. She received the B.S. degree from the Shanxi Datong University in 2018. She is currently pursuing the M.S degree in College of Electronics and Information Engineering, Shanghai University of Electric Power. Her research interests include UWB-MIMO antenna, flexible antenna.