EBG Assisted Micromachined Patch Antenna: Analysis, Design and Applications

Patch antennas with bulk micromachined GaAs substrate suitable for on-chip integration with active devices are investigated. Advantages of such integrated antennas are increased bandwidth, improved efficiency, etc. Micromachining reduces the surface wave generation whereas Electromagnetic bandgap (EBG) blocks the surface wave propagation. Surface wave is the main hurdle for patch antennas printed on high permittivity substrate used for MMICs like GaAs, Silicon. We have demonstrated that using EBG structure with micromachining on the same GaAs substrate increases the antenna performance significantly. It has been observed that the bandgap diagram for EBG structure in the ground plane is different from the bandgap diagram for EBG structure in the substrate. A new bandgap diagram for EBG structure in the ground plane is obtained. Then, EBG structures in the ground plane and substrate are integrated. It shows a considerable improvement in the EBG performance with an increased EBG bandwidth, deeper and smoother insertion loss in the EBG frequency range.