一种新型220GHz太赫兹分谐波混频器设计

Design of a Novel 220GHz Terahertz Sub-harmonic Mixer

设计了一款基于肖特基势垒二极管和改进型CSMRs滤波器结构的新型220GHz太赫兹分谐波混频器。射频端采用基片打孔并镀金的方式实现直流接地。本振低通滤波器和中频低通滤波器均采用不同的改进型CSMRs滤波器结构,与常用的高低阻抗滤波器相比,明显减少了滤波器的尺寸,具有更宽的阻带。整个混频器电路采用50um厚的石英基片,本振部分采用悬置微带形式,中频部分采用微带形式。经过仿真优化设计,本振驱动功率3.5mW,射频功率0.1mW,固定本振频率120GHz,仿真结果表明:在射频频段201GHz—239GHz范围内,变频损耗优于8dB,最小变频损耗是7dB@219GHz。其中,射频频段210GHz—230 GHz内,变频损耗优于7.3dB。在射频频段189GHz—242GHz范围内,回波损耗优于10dB。本论文的工作对于太赫兹分谐波混频器等器件的集成化和小型化研究具有重要的意义。

A novel 220 GHz terahertz sub-harmonic mixer based on Schottky barrier diode and improved CSMRS filter is designed in this paper. The quartz substrate at the RF port realizes the DC grounding by punching holes and plating gold. Different from commonly high-low impedance filters, two improved CSMRs filter structures are applied to the LO low pass filter and the IF low pass filter, which significantly reduce the size of the filter with wider stop-band. The whole mixer circuit uses 50 um thick quartz substrate, the LO part adopts the suspension micro-strip structure while the IF part adopts the micro-strip structure. The RF power is 0.1mW with the LO power 3.5mW, the simulated results show that the single sideband(SSB) conversion loss of mixer is greater than 8dB with the RF range 201 GHz to 239 GHz. The optimal conversion loss is 7dB at 219 GHz.The SSB conversion loss of mixer is greater than 7.3dB with the RF range 210 GHz to 230 GHz. The RF return loss is greater than 10 dB with the RF 189 GHz to 242 GHz. The work of this paper is of great significance for the integration and miniaturization of terahertz sub-harmonic mixer.