Comparative Analysis of a Super-Wideband Millimeter Wave Array Antenna for Body-Centric Communications

Abstract

The future of wireless technology is moving towards millimeter wave bands due to a surge in the use of wearable gadgets in current wireless bands. The 60 GHz band is unlicensed around the world and has gathered high research interest. At this band, the atmospheric absorption is very high, which results in short-range communication. High gain antennas are a core requirement for operating at 60 GHz. In this paper, we are proposing three different arrays consisting of 2, 3, and 4 elements of a novel patch design. The radiating patch consists of a semicircular disc fed by a microstrip feed line. The ground plane has been etched into a novel shape. The radiator and the ground plane are attached to a 1.5 mm thick FR-4 substrate which has a relative permittivity of 4.3. The radiating elements are connected linearly to form arrays. In free space, all three arrays achieved a very wide bandwidth of more than 20 GHz, and the maximum gain varied from 3.44 dBi to 6.2 dBi. The arrays were also simulated under human body conditions by modelling a three-layer phantom. At different distances from the phantom, the maximum gain increased by more than 1 dBi. The antenna shows 4.855 dBi, 5.032 dBi, and 6.66 dBi gain for 2 array, 3 array, and 4 array, respectively, when simulated on the three-layer human model phantom. The antenna has a very good VSWR value for all three array structures. On the human body phantom, the proposed antenna design in this research shows 1.214, 1.120, and 1.023 VSWR values for 2 array, 3 array, and 4 array, respectively. The efficiencies were highly affected, as expected from patch antennas. The simulation results are obtained from CST Microwave Studio.