Design of a Compact Ka-band Balanced Mixer Based on a Novel Wide-band Equivalent Circuit of the Schottky Diode

  • Jinchao Mou
  • Weihua Yu
  • Yong Yuan
  • Xin Lv


A compact Ka-band balanced mixer based on a novel Schottky diode model is presented in this paper. According to its physical structure, a novel 3D electromagnetic model of the Schottky diode is proposed. Meanwhile, a wide-band equivalent circuit is built, which takes all high frequency effects existing in the diode into account. All the parasitic reactances are extracted from the electromagnetic model-based S-parameters up to 110 GHz. Based on the proposed equivalent circuit, a Ka-band balanced mixer is designed and optimized, where bandpass filters with open stubs and a lowpass filter based on defected ground structure cells are used. The measured results show that the conversion loss is below 9 dB from 30 GHz to 40 GHz with the minimum of 6.7 dB at 35 GHz. The normalized size of the mixer is only 3.3λ g  × 3.3λ g , whereλ g is the wavelength at 35 GHz.


Schottky diode Balanced mixer Wide-band equivalent circuit Defected ground structure 


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© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Laboratory of Microwave Communication and Electronic SystemsBeijing Institute of TechnologyBeijingPeople’s Republic of China

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