The analysis of ultra wideband like fractal microstrip patch antenna using non-uniform photonic bandgap substrate structure

The characteristics of new ultra wideband (UWB) like fractal microstrip patch antenna using a non-uniform photonic bandgap (PBG) substrate structure have been analyzed using a full 3D electromagnetic field inside the structure based on the finite element method. UWB technologies have been developed to exploit a substantially new spectrum resource and to realize ultra high-speed communication, high precision radar, and other sensing systems. The antenna is sensitive to the PBG in the dielectric substrate with periodic patch structure and has UWB in the range of approximately 4 GHz to 20 GHz and wideband above 20 GHz. These PBGs enhance some modes and weaken others; this property has been used to control the antenna bandwidths. The proposed antenna is constructed on a ground plane of thickness 0.1 mm and FR-4 epoxy substrate of thickness 1.6 mm with relative permittivity 4.4. Radiation characteristics for the designed antenna, such as return loss, input impedance, near field radiation pattern and 3D-polar radiation pattern, with respect to changes in the patch structure are obtained using numerical simulations.