Improvement in Depth–of–Return-Loss & Augmentation of Gain-bandwidth with Defected Ground Structure For Low Cost Single Element mm–Wave Antenna

Abstract

The present research involves the design, fabrication & testing of a low-cost wide-band mm-Wave prototype antenna. The FR4 structure was composed of a Defective Ground Structure (DGS), a Concentric Circle at the bottom edges, and a Rectangular Radiating Patch (RRP) etched with a circle. To improve gain for a wider spectrum, the DGS is created by etching a dumbbell in the center and two semi-elliptical slots at the upper edges. 3.89 GHz (30.26–34.15 GHz) is found to have a bandwidth of -10 dB, and 99% power is obtained with a mismatch loss of less than 0.044 dB for the 30-31.59 GHz band. Additionally, it has a 5–dBi enormous gain-bandwidth of 2.50 GHz (30.47–32.97GHz) & a 3–dBi gain-bandwidth of 3.89 GHz (30.26–34.15GHz). Furthermore, four gain peaks are attained: 9.83 dBi at 31.3 GHz, 8.15 dBi at 32.64 GHz, 6.16 dBi at 33.47 GHz, and 6.05 at 33.74 GHz. Axial ratio, group delay, and directivity are a few more quality metrics that are examined. Anechoic chamber and Rohde & Schwarz ZNB 40 Vector Network Analyzer (VNA) Bench are used to measure antenna parameters. The constructed framework is appropriate for 5G and beyond intelligent network based next-generation (5G) communications, as well as 5G Local Multipoint Distribution Services (LMDS) applications in the mm–Wave range and futuristic robotic control devices. Lastly, an equivalent circuit for the suggested structure is created and examined.