太赫兹宽带分谐波混频器设计

Design of THz Broadband Sub-Harmonic Mixer

太赫兹分谐波混频器的变频损耗、噪声系数等指标与基波混频器相近,且本振频率为射频频率的一半,大大降低了本振源的设计难度和制作成本,是高性能太赫兹接收前端的关键部件。本文介绍了一种覆盖全波导带宽的太赫兹宽带分谐波混频器的设计,对电路中射频波导至悬置带线过渡结构和本振中频双工器进行仿真和优化设计。并以0.14~0.22THz分谐波混频器为例进行设计和制作,测试结果表明0.14~0.22THz分谐波混频器在全波导频段内最大变频损耗低于15d B,中频3d B带宽大于20GHz。

The frequency conversion loss and noise figure of THz Sub-harmonic mixeris close to the fundamental mixer, while the LO frequency is the half, so the design difficulty and production costs of LO is greatly reduced. THz sub-harmonic mixer isa key component of the THz receiver front-end. In this paper, a whole waveguide bandwidth broadband THz Sub-harmonic mixer was designed, the RF waveguide to suspended line transition and LO&IF duplexer were simulated and optimized. Taken the0.14~0.22 THz sub-harmonic mixer as an example, test results indicate that, the conversion loss of the sub-harmonic mixer is less than 15 d B in 0.14~0.22 THz, and the IF 3d B band is higher than 20 GHz.