Open AccessDevelopment and performance analysis of conformal UWB wearable antenna under various bending radii
Author(s) -
Narbada Prasad Gupta,
Mithilesh Kumar,
Raaz Maheshwari
Publication year - 2019
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/594/1/012025
Subject(s) - antenna (radio) , bending , dissipation factor , bent molecular geometry , radiation pattern , return loss , materials science , optics , bend radius , acoustics , physics , dielectric , electrical engineering , optoelectronics , engineering , composite material
Antennas for off-body wearable applications needs to be flexible and its electrical characteristics should be stable in different body postures, different bending or stretching environments. Therefore, the designed antenna should be such that, even if the antenna is bent frequently, it should operate properly. In this paper, a conformal UWB antenna is reported which has been optimized to be conformal to any body shape and size. The proposed antenna has been designed on RT Duroid substrate with dielectric constant of 2.2 and loss tangent 0.0009. The thickness of the material is 0.127 mm. Due to low thickness; it can easily be bent and mounted on curved surfaces. The size of the antenna is 35 × 31 mm 2 . To accomplish the design process, two different bending radii have been considered to bend the proposed antenna. The two bending radii of 25 mm and 50 mm have been chosen; one corresponding to the arm of a healthy child of around 5 years age and another corresponding to a healthy person of age about 35 years with medium built. The simulated radiation efficiency and total antenna efficiency are more than 60% for the bending at 25 mm and 50 mm radii in the UWB frequency range from 3.1 GHz to 10.6 GHz. The gain of the proposed antenna for both the bending radii is changing from 1.4 dB to 5.3 dB. The return loss of the proposed antenna is obtained for 25 mm and 50 mm bending radii of curvatures and it is below 10 dB in UWB range. A prototype of proposed antenna has been fabricated and tested on Rohde & Schwarz 40 GHz VNA. Measured results are in close agreement with simulation results.