A novel modified U-shaped microstrip antenna for super wide band (SWB) applications

Abstract

In this work, a novel wideband microstrip modified slotted U-shaped printed monopole antenna operating from 3 to 20 GHz for super-wideband applications is proposed. To have an effect on the enhancement of bandwidth and to get better impedance matching over the frequency band, three modifications are introduced, the first one is to print two symmetric triangular shaped slots in the radiating element and the second one is to modify the partial rectangular ground plane to be defected ground plane by slotting three triangular structures. The third modification is to embed a circular slot in the center of the patch for integrating the entire FCC band (3.1–10.6 GHz) in the super wide band antenna. Both CST Microwave Studio and Ansoft HFSS 3-D EM solver were used for the simulation analysis of antennas while measurements after fabrication are performed by applying ZVB 20—vector network analyzer 20 MHz–20 GHz. The average maximum gain of the antenna is 5.72 dB with good radiation patterns. The antennas have only been measured up to 20 GHz (the upper frequency limit of the laboratory vector network analyzer device), simulations results both in CST and HFSS shows satisfactory design’s performance up to 40 GHz. So as this antenna is a candidate to fulfils the future UWB spectrum requirements in a very wide band. A good agreement between the measured and simulated results is achieved in term of return loss in the measured band (up to 20 GHz).