“…Amid these studies, various antenna design techniques, such as inverted-F, planar inverted-F antenna (PIFA), monopole, and loop, have been proposed. To the above-mentioned structure, slot antennas have also been applied in 5G communication due to their simple structure, wide operation band, and easy integration of active equipment [21][22][23][24][25][26][27]. However, when being used for 5G NR band applications, these slot antennas still have significant margins for improvement in terms of bandwidth utilization and other areas.…”