Design and Implementation of UWB Slot-Loaded Printed Antenna for Microwave and Millimeter Wave Applications

In this paper, single-layer ultra-Wide Band (UWB) microstrip patch antennas loaded with asymmetrical U-shaped slot in both microwave and millimeter wave applications are presented. These novel antennas cover a fractional bandwidth around 40% in both microwave and millimeter applications. The applications cover the C-band (4-8) GHz, V-band (40-75) GHz, and W-band (75-110) GHz. In addition to that, it is the sole article that cover the bands (5.15-5.825) GHz and (8.025-8.4) GHZ for WiMaX and ITU band applications, respectively. Moreover, it covers three bands for Automotive radar applications within (71-76) GHz, (81-86) GHz, and (92-95) GHz, in addition to further 5G/mm-wave applications at 60 GHz. Each antenna is coaxial fed and implemented on a Roger 5880 substrate with relative dielectric constant of 2.2, thickness of $1.575~mm$ and loss tangent of 0.0009. They operate over the frequency band (5.5-9.5) GHz for microwave band and (55-95) GHz for mm-wave band. To achieve either a notch in other bands or develop a multi-band structure, the conventional ground is replaced by two different structures. The first ground is an array of patches and the other is a mushroom ground. The first ground results in a notch within the band (73-79) GHz while the second one achieves a multi-band within (55-68) GHz and (81-95) GHz. Both antennas are simulated and verified using Finite Difference Time-Domain analysis (FDTD); CST Microwave Studio and Finite Element Method (FEM); Ansoft HFSS. For microwave band, the antenna is fabricated and measured for verification. Concerning the mm-wave version, three different types of ground planes are presented; traditional, periodic structure of patches and mushroom. The structure with periodic patches conducts the same band as the traditional ground plane does. This is a prestep for the design of the notches. The mushroom ground is carried out for multi-band applications. The average gain of the antennas is 7 dB.The measured two dimensional cuts of the radiation pattern, radiation efficiency, and reflection coefficient of the microwave version are presented and are in good agreement with the simulated results while for the mm-wave antenna the same parameters are simulated with two different methods and are in good agreement.