A K_a-band antenna based on an enhanced Franklin model for 5G cellular networks

This article presents a millimeter-wave antenna to cover 28- and 38-GHz bands recommended by Federal Communications Commission for the 5G cellular networks. The conventional narrowband Franklin antenna is modified geometrically to transform into a multiband antenna provided with a linear array arrangement to fit multiple patches in a compact assembly to achieve smaller form factor and improved gain profile. The suggested structural modifications are deployed to diversify the fundamental theory of Franklin antennas to generate wideband and multiple resonances. The measured results show an impedance bandwidth of 28–39 GHz covered by the three resonances. The realized gain is above 7 dBi in the complete range of operation, while the peak gain is 10.23 dBi at 36 GHz. The proposed antenna signifies its high potential to fulfill demands of 5G wireless systems.