Photoconductive switching using silicon and its applications in antennas and reconfigurable metallodielectric Electromagnetic Band Gap (EBG) structures

The aims of this research work were to investigate the microwave properties of photoconductive semiconductor switches (PCSS), and how the properties might be used to optically control microwave and millimetre wave devices. Tunable devices (such as antennas, filters and metamaterials) have the ability to increase flexibility performance in multiband systems for example. In this thesis the performance of microwave switches from microstrip discontinuities, with high resistivity silicon dice placed cross the gaps were investigated. Under optical illumination, the electrons in silicon can be excited from the valence band to the conduction band. This photoconductivity in silicon has been employed to design a small microwave switch that can be operated using optical signal. The optically activated switch offers a wide range of applications. Potential applications have been demonstrated in integrating the microswitch in microstrip patch antenna, microstrip couple line filter, and Electromagnetic Band Gap (EBG) structures.