An Extremely Low-Profile and Longilineal Dual-Band Shorted Patch Antenna for 5G Mobile Terminal Applications

This letter proposes an extremely low-profile, longilineal dual-band shorted patch antenna suitable for narrow and elongated space applications. By etching a vertical slot, four resonant modes of the shorted patch, namely TM0.5,0, TM0.5,1, TM0.5,2,and TM0.5,3modes, are adjusted to realize the initial dual-band operation. Then, two symmetrical transverse slots are etched to adjust the impedance matching. The bandwidth of each band is extended to 200 MHz by incorporating the parasitic modes of parasitic patches on either side into each band separately. The covered frequency bands are partial N78 [(3.4 to 3.6) GHz] and partial N79 [(4.8 to 5.0) GHz], suitable for Chinese communication operators. The proposed antenna is fabricated and measured. It has an extremely low profile of 0.011λLand a longilineal shape of 0.711λL× 0.113λL(λLrefers to the vacuum wavelength at the lowest frequency of the operation band). Measured results show that the impedance bandwidths of −6 dB are 3.39 GHz to 3.59 GHz (200 MHz, 5.73%) and 4.80 GHz to 5.00 GHz (200 MHz, 4.08%), respectively, with measured average total efficiencies of −2.98 dB and −3.11 dB, respectively.