A novel reduced-size rat-race broadside coupler and its application for CMOS distributed sub-harmonic mixer

Chun Lin Kuo, Che Chung Kuo, Chun Hsien Lien, Jeng Han Tsai, Huei Wang

Research output: Contribution to journalArticle

14 Citations (Scopus)


A broadband distributed sub-harmonic resistive field effect transistor mixer with a novel modified rat-race broadside coupler using a 0.13-μm CMOS foundry process is presented in this letter. Using the broadside coupler, a reduced-size rat-race is fabricated with a compact size of 110 × 80 μm2, From the measurement results, the mixer achieved a conversion loss of 12 dB from 32 to 70 GHz of RF frequency. The passive sub-harmonic mixer has zero power consumption. With the modified rat-race broadside coupler, the mixer achieves a good LO-IF isolation of better than 30 dB and a compact core chip size of 0.55 × 0.4 mm2.

Original languageEnglish
Article number4459262
Pages (from-to)194-196
Number of pages3
JournalIEEE Microwave and Wireless Components Letters
Issue number3
Publication statusPublished - 2008 Mar 1



  • CMOS
  • Distributed circuit
  • Monolithic microwave integrated circuit (MMIC)
  • Sub-harmonic mixer

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Electrical and Electronic Engineering

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