5 THz混频二极管等效电路模型研究

采用电磁场和电路联合仿真，基于直流测试和三维电磁建模仿真技术，建立了截止频率5 THz的混频肖特基二极管的等效电路模型。重点研究了二极管的非线性结模型和外围结构三维电磁全波仿真模型，构建了考虑实际电路形式的四端口三维电磁全波仿真模型。该等效电路模型可用于太赫兹低频段混频模块设计，该模型的建立方法也为更高频段模型的建立提供了一种参考。基于该模型设计了一款220 GHz分谐波混频器，在192~230 GHz宽带范围内，双边带变频损耗小于10 dB，测试结果与仿真结果较为一致。

Equivalent circuit model study of mixing diode with cut-off frequency of 5 THz

An equivalent circuit model of mixing Schottky diode with cut-off frequency of 5 THz was reported based on DC measurement and 3-D electromagnetic(EM)simulation combined of EM simulator and circuit simulator. The model of nonlinear Schottky junction and 3-D periphery structure full-wave simulation model was researched carefully, the four-ports model considered real circuit topology was established. The equivalent circuit model can be used for design of mixers worked at the lower end of terahertz band, the methodology of this diode model was a reference of much more higher terahertz frequency. A sub-harmonic 220 GHz wideband mixer was designed based on the model, the double sideband conversion loss was less than 10 dB in the range of 192 GHz to 230 GHz, the measured result was well with the simulated result.