Array Antenna with HIS Metasurface for mmWave Imaging Applications

Compact Wearable Antenna with Metasurface for Millimeter-Wave Radar Applications

“…Regarding the antennas on substrates with identical ε r values or as close as possible to that of the antennas presented in this work [ 24 , 43 , 44 , 45 , 46 ], all of them provide G results much lower than the ones required in the target application. Although [ 43 ] shows a considerable bandwidth and is quite compact, it is on paper, which makes it unsuitable in contact with sweat or humidity and not very robust.…”

“…Moreover, its radiation efficiency is one-third of that achieved by the designs proposed in this work. It also stands out [ 24 ] for the G and BW that it provides considering its small size, although its performance is outmatched by the proposed antennas. The antenna designs corresponding to ε r values, which are slightly higher than 3 and lower than 3.6, [ 40 , 47 , 48 , 49 , 50 ], provide results of G lower than 14 dBi and with BW similar to that shown by the basic antenna of the present work [ 47 , 48 , 50 ], and in all cases lower than that provided by the antennas with metasurfaces proposed in this work.…”

“…In addition, these techniques improve only some of the antenna parameters, but not all at once (or considerably improve some at the expense of certain deterioration of others). Other recent works including [ 24 ] focus on either trying to reduce the size of an array of microstrip patches with corporate (parallel) feeding, improving some of its radiation parameters, but slightly worsening others and keeping the bandwidth, or slightly improving all the radiation parameters but not the bandwidth, while preserving size, based on a reduction in the coupling between the array patches by arranging a wall of unit cells between them and the suppression of the surface waves, with more than one row of unit cells in the front part.…”