Split Ring Resonator and Slot Loaded Coplanar Waveguide Fed Quad-Notched Ultra Wide Band Antenna

A compact coplanar waveguide (CPW) fed quad-notched ultra-wideband (UWB) antenna is proposed in this article. The proposed antenna consists of a set of regular geometric slots, including a rectangle, semicircular, and pentagonal stub, as well as a microstrip feedline with a total length of 35.4 mm and a width of 28.82 mm. To generate one notched frequency band at (3.78–4.15) GHz (9.34%), the antenna uses one inverted U-shaped slot at the pentagonal stub of the antenna. A combination of L-shaped slots are etched out in the upper surface of the antenna to obtain the dual WLAN frequency band notches at (5.15–5.31) GHz (3.05%) and (5.6-5.9) GHz with (5.21%). Rectangular Split Ring Resonator (SRR) is then embedded in the antenna’s lower surface to realize a notch band at (7.25–7.80) GHz (7.3%). Except in quad frequency stop bands at (3.78–4.15) GHz, (5.15–5.31) GHz, (5.6– 5.9) GHz, and (7.25–7.80) GHz, the proposed UWB microstrip antenna has an operational impedance bandwidth ranging from 3 to 11.2 GHz. A systematic development of the UWB antenna on FR4 substrate is reported, beginning with a pentagonal stub fed by CPW for wide impedance bandwidth, improved through asymmetrical geometry over 3.1–10.6 GHz, and gradually adding a U-shaped slot for C-band notch (3.78–4.15 GHz), dual L-shaped slots for WLAN notches (5.15–5.31 GHz and 5.6–5.9 GHz), and ground-plane SRR for SHF notch (7.1–7.8 GHz), ending with an optimized quad-notched design reducing mutual coupling for interference-resistant applications. The proposed quad-notched UWB antenna has been effectively developed, prototyped, and verified. The simulation and measurement results are thoroughly examined and evaluated. The fabricated antenna is justified for use in wireless applications such as military radar systems, medical imaging, and consumer electronics.