5G Dual (S-/Ka-) Band Antenna Using Thick Patch Containing Slotted Cavity Array

An S-/Ka-band shared-aperture antenna with frequency switching function for 5G applications is proposed in this letter. The proposed antenna comprises a thick patch containing a slotted cavity array (TPCSCA), S-band feeding structure, and coaxial cables for Ka-band. The TPCSCA is designed using 16 Ka-band slotted cavity antennas inside an S-band thick patch. Half of these Ka-band antenna elements radiate a +45° slanted polarization wave, whereas the others radiate a -45° SP wave. These elements are arranged in the form of a checkerboard and fed by coaxial cables. The S-band feeding structure is designed as a microstrip-fed slot and operates the TPCSCA as a TM
₀₁₀
mode patch antenna in S-band. The measurement results show realized gains of 4.06-5.35 and 12.0-14.5 dBi over the S-band (3.44-3.56 GHz) and the Ka-band (27.54-28.46 GHz), respectively. The -3 dB beam steering coverage for the Ka-band is more than ±40° for both polarizations.