FULL-WAVELENGTH DIPOLE ANTENNA ON A GAAS MEMBRANE COVERED BY A FREQUENCY SELECTIVE SURFACE FOR A TERAHERTZ PHOTOMIXER

An antenna consisting of a full-wavelength dipole on a GaAs membrane covered by a frequency-selective surface is proposed for improved output power from photomixers used as terahertz (THz) sources. The antenna structure reduces the vertical dimension of a typical photomixer antenna using a substrate lens while still exhibiting high total efficiency and high directivity. The resulting antenna after optimization produced an input resistance of 3870 Ω and a radiation efficiency of 60%, corresponding to a total efficiency of approximately 48.3% and a maximum directivity of 20.2 dBi at the resonance frequency of 1.03 THz. The proposed antenna is expected to be a promising alternative THz photomixer design.