Study on Defected Ground Structure Models with Miniaturized Patches for Broadband Wireless Systems

—This study presents a Defected Ground Structure (DGS) mechanism and improves its antenna properties. Three DGS models are discussed: two including a single antenna and one including an array microstrip antenna design. The microstrips are designed for broadband wireless frequencies of 2.1 GHz (5G Technology) for a single antenna, and 5.8 GHz (wireless local area network) for an array antenna. These frequencies are achieved using three shapes of DGS in the simulations and the results are suitable for broadband applications. The antenna patches are rectangular with two types of DGS, and an array circular with one type of DGS. The results show the DGS provides better bandwidth and gain for a single antenna. Nevertheless, DGS achieves gain enhancement for an array antenna and this design yields a miniaturized array antenna of 69.92% and 73.47% in width and length, respectively. The three shapes of DGS have different designs: rectangular patch antenna with frame-shaped DGS, rectangular antenna with rectangular slot-shaped DGS, and array circular antenna with rectangular slots of DGS. A rectangular patch antenna with frame-shaped DGS and an array circular antenna with rectangular slots of DGS yields bandwidths of 533 MHz and 327 MHz. The single antenna improves the fractional bandwidth by 25.38% with a miniaturized patch. Nonetheless, the array circular antenna with DGS obtains a gain enhancement of 16 dB greater than the initial array without DGS.