Design of miniaturized dual-band filtering antenna with improved selectivity utilizing square complementary split ring resonator for 5G MM-wave automobile applications

In this article, the design for 5G millimeter wave (mm-wave) applications of miniaturized low-profile dual-band filtering antenna with increased gain and high selectivity using moon-shaped parasitic patches and square complementary split-ring resonator (SCSRR) is featured. The proposed design comprises of two rectangular stubs and two separate moon-shaped parasitic patches that operate for wideband impedance matching and the improved passband selectivity is achieved by employing an inter-digital line with SCSRR, which in turn is implemented to obtain second passband with improved dual-band selectivity. In addition, the filtering antenna's operating bands can be modified to the desired frequency range by individually tuning the inter-digital line, SCSRR size and location. The filtering antenna is designed to show that it operates at 26.5–29.5 GHz (Europe) and 37–43.5 GHz (USA) suitable for 5G mobile communication. Furthermore, the presented filtering antenna features are investigated in an antenna housing effect environment to examine the 5G mm-wave spectrum for automobile applications, whereas the radiating characteristics are examined in free space environment for experimental validation. By and large, the experimental validation reveals the four radiation nulls and dual band bandpass filter responses delivers a passband average gain of 4.2 and 4.37 dBi. The presented filtering antenna configuration exhibits dual band radiation in Ka-band spectrum with constant gain, radiation efficiency and radiation pattern characteristics for 5G mm-wave band high speed automobile communication.