Design of a Broadband High-gain Patch Antenna for 5G Millimeter-wave Applications

In the letter, a planar broadband high-gain patch antenna is proposed for 5G millimeter-wave (mm-wave) applications. It consists of two 0.787-mm-thick Rogers RT/duroid 5880 dielectric substrates and three copper cladding layers. In the top copper layer, there are two pairs of rectangular patches. Each pair of rectangular patches are connected with a meandered U-shaped thin strip. To enhance the band of operation and simultaneously improve the impedance matching, a stepped narrow strip is introduced and placed between the two pairs of rectangular patches. The middle and bottom copper layers together with three metal columns form a substrate integrated waveguide (SIW) cavity. A narrow slot is etched in the middle copper layer along the long wall of the SIW cavity so as to couple the electromagnetic energy to the radiating elements located in the top copper layer. Simulations demonstrate the proposed antenna realizes a broad band of 25.1–30.7 GHz by merging three different resonant frequencies. Across the band of operation, the antenna obtains a high gain with a peak value of 11.44 dBi. Moreover, unidirectional radiation patterns with front-to-back ratio higher than 20 dB can be found and the co-polarization is better at least 20 dB than the cross polarization over the whole band of operation. With all these good performances and simple planar integrated configuration, it is easy for the antenna to develop into an antenna array.