3D Printed Extended Lens as a Button Antenna for Off-Body Links at 60 GHz

This paper presents a 3D printed extended hemispherical lens antenna for Body Centric Communications in 60 GHz band. The prototype consists of a 3D printed lens made of Polylactic Acid with three planar broadside patch antenna elements used as a source for the lens. The direction of the main beam antenna is switched by changing the excitation of source elements. The measured overlapping impedance bandwidth of the fabricated antenna is from 57.27 GHz to 60 GHz with reflection coefficient better than -10 dB. The main beam direction switches in broadside direction with 3 dB angular coverage from -29.2 degrees to +30 degrees by changing the radiating elements at 60 GHz. The measured gain is 15.28 dBi at 60 GHz. The beam switching capabilities and high gain with broadside radiation characteristics make the proposed antenna a suitable candidate for off-body links at 60 GHz. The effect of placing the antenna structure over the body is also studied in this paper. The body to off-body link measurement is successfully demonstrated with extended lens over the body and an open-ended waveguide as an external node.