keywords gallium arsenide (gaas) substrate longitudinal and transverse slot arrays metamaterial on-chip antenna substrate integrated waveguide (siw) terahertz (thz) transceiver antenna arrays buffer amplifiers circuit oscillations gallium arsenide high pass filters iii-v semiconductors metamaterial antennas metamaterials oscillistors power amplifiers radio transceivers semiconducting gallium slot antennas transceivers average output power fully integrated metamaterial (mtm) on chip antenna substrate integrated waveguide technologies terahertz terahertz region transverse slot substrate integrated waveguides