Modified Koch borderline monopole antenna for THz regime

摘要

A modified Koch frontier, super wide band antenna is designed and analyzed in both frequency and time domain. A novel combination of partial ground structure with asymmetric polygon shape patch is proposed in this letter. Higher order TM modes are excited in the structure and amalgamated in order to provide an impedance bandwidth of 139. Average radiation efficiency of 85 is obtained throughout the resonating band of the antenna. Electrical shortening of antenna is achieved by modifying shape of patch to yield an operating bandwidth of 12.5 THz (2.7-15.2 THz) with a peak gain of 6 dBi. Furthermore, antenna behaves as monopole antenna for lower frequencies of operating bandwidth. Pulse preserving property in three direction paradigm is verified for far field radiation of the antenna and a high fidelity factor of 0.9597 is obtained. Presented antenna is best suited to be used as a terahertz (THz) pulse generator and detector in THz pulse imaging (TPI) systems for dental caries, dermatological practices, breast cancer and brain tumor detection.