Open AccessInterconnected CPW Fed Flexible 4-Port MIMO Antenna for UWB, X, and Ku Band Applications
Author(s) -
Arpan Desai,
Jayshri Kulkarni,
M. M. Kamruzzaman,
Stepan Hubalovsky,
Heng-Tung Hsu,
Ahmed A. Ibrahim
Publication year - 2022
Publication title -
ieee access
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.587
H-Index - 127
ISSN - 2169-3536
DOI - 10.1109/access.2022.3179005
Subject(s) - aerospace , bioengineering , communication, networking and broadcast technologies , components, circuits, devices and systems , computing and processing , engineered materials, dielectrics and plasmas , engineering profession , fields, waves and electromagnetics , general topics for engineers , geoscience , nuclear engineering , photonics and electrooptics , power, energy and industry applications , robotics and control systems , signal processing and analysis , transportation
A coplanar waveguide (CPW) fed flexible interconnected 4-port MIMO antenna is proposed for UWB, X, and Ku band applications having a size $0.67\lambda \times 0.81\lambda \times 0.0028\lambda $ (at 3.58 GHz). The antenna parameters are characterized by using sets of real measurements to validate the antenna design and modelling. A precise milling machine is used for fabricating the single and 4-port antennas over a flexible FR-4 Substrate. Vector network analyser (VNA) is used for measuring scattering and transmission coefficients. As well as, a shielded anechoic chamber is utilised for measuring the far field radiations and the gain of the antenna under test (AUT). The basic antenna that is a part of the 4-port structure consists of a CPW fed octagonal structure surrounded by an octagonal-shaped slot. The MIMO ability is achieved by arranging the 4 identical elements symmetrically in a successive rotational means for achieving good polarization diversity. The connected ground between the elements is achieved by introducing a plus-shaped slotted structure separated by a slotted diamond at the center in the 4-port structure. None of the slots touches each other thus ensuring the common reference while maintaining the inter-element isolation better than 15 dB. The antenna demonstrated maximum gain and minimum efficiency of 6.8 dBi and 89%, respectively besides attaining a 10-dB impedance bandwidth of 125.83% (3.89-17.09 GHz) and envelope correlation coefficient (ECC) < 0.02. Finally, the 4-port flexible antenna is tested in terms of S parameters and ECC under bending conditions along the X and Y axis followed by a time-domain analysis that exhibited very good performance.