Design of sub-THz log-periodic antenna for high input impedance

As the development for Terahertz (THz) system is highly demanded, the detecting antenna requires a very high input impedance for a good matching with the photomixer. The detecting antenna is connected to the photomixer, requiring very high input impedance, so that the impedance matching between these two elements is significantly important. We propose a Log-Periodic antenna for high input impedance which operates in the sub-THz frequency range. The proposed antenna achieves a high input impedance of approximately 1000 Omega at the resonant frequency of 72 GHz.