Design of a 231-GHz Solid-State Receiver Front-End Based on Inverted-MS Structure Package and Schottky Diodes

This paper presents the design of a 231-GHz solid-state receiver front-end based on Schottky diodes. A novel inverted microstrip line structure (inverted-MS) is proposed as a replacement for the conventional gold wire bonding technique for a 231-GHz low-noise amplifier (LNA) module chip packaging, with the aim of achieving enhanced performance. The results of the measurements demonstrate that the small-signal gain of the LNA module is in the range of 14 to 18 dB over the frequency range of 220 to 240 GHz. In the 115-GHz tripler and 231-GHz sub-harmonic mixer design, the parasitic effect of the diode is illustrated through the use of 3D electromagnetic (EM) modeling, with the simulator employed in conjunction with 3D full-wave and harmonic balance. The output power of the 115-GHz frequency multiplier amplification link exceeds 3 mW within the frequency range of 106 to 121 GHz, with an input power of 21 dBm. Ultimately, the receiver front-end devoid of the LNA module exhibits a down-conversion loss of 6.8–9.5 dB. Moreover, the receiver front-end incorporating an LNA module demonstrates a down-conversion gain of 9.2–12.2 dB and a noise figure of 8–10.6 dB at an LO frequency of 110–120 GHz. The proposed prototype possesses the merits of a high LO multiplier factor, high conversion gain, and low-noise figure, which may provide a solution for further breakthroughs in the terahertz solid-state devices.