A 2× 2 integrated heterodyne receiver array for terahertz imaging application

This paper presents a 2 × 2 integrated heterodyne receiver array for THz imaging applications. The cell includes a differentially-fed antenna with a Schottky diode across its vertexes. The Schottky diode is designed and fabricated on GaAs substrate, which acts as a mixing device. To enhance the gain of the differential antenna, a high-resistivity silicon lens is used. In addition, the lens can also be used for form multi-beams. The cutoff frequency of the fabricated Schottky diode is 3.2 THz. The measured results show that the cell has the conversion loss between 10.5 dB and 12.5 dB from 335 GHz to 350 GHz and the noise temperature ranges from 4100 K to 5300 K.