An array antenna based on coplanar parasitic patch structure

This article presents a 5 × 5 array antenna with the coplanar parasitic patch structure. The array consists of 25 patches and 24 resonance branches. Two center patches, which are fed by two high frequency SMA probes, serves as the driving elements, while the surrounding 23 patches are the parasitic elements. The resonance branches of the array antenna are used as a feed network to transmit the coupling energy. As a result, 25 patches on the substrate can be stimulated simultaneously. The array antenna has a simple feed structure and compact size. Compared with a standalone antenna, the coplanar parasitic patch array antenna has the advantages of wide bandwidth and high gain. Experimental results show that the proposed antenna operating band is 17.2–21.3 GHz; the impedance bandwidth is 20.5%; and the peak gain is 14.2 dBi.