This paper presents a high-gain, wide-beamwidth planar antenna on a thin substrate for the unlicensed 60 GHz band, with a substrate thickness of 0.05 λ0 and a single RF chain. The proposed antenna achieved a peak gain of 7.8 dBi and beamwidth of 129° while maintaining a stable gain and wide angular coverage across 57~64 GHz. These results were enabled by the incorporation of supporting directors and a guiding wall that induced additional fields and structurally stabilized the radiation characteristics, thereby ensuring a robust performance with a simple configuration. The proposed antenna effectively mitigated communication blind spots caused by misalignment in short-range millimeter-wave scenarios and demonstrated a strong potential for compact and energy-efficient next-generation wireless communication systems.
Han et al. (Sun,) studied this question.