Compact Rat-Race Coupler-Based Microstrip Balun Without Any Isolation Port

  • Ankita KumariEmail author
  • Tamasi Moyra
  • Priyansha Bhowmik
Conference paper
Part of the Advances in Intelligent Systems and Computing book series (AISC, volume 810)


In this work, a compact miniaturized microstrip balun is proposed by removing the isolation port of a Rat-Race Coupler (RRC). The proposed balun consists of six quarter-wavelength Transmission Line (TL), and the TL is designed using interdigital capacitor and high impedance TL in parallel configuration. The fractional bandwidth (FBW) of RRC and balun are 37.5% and 33%, respectively, at centre frequency 2.4 GHz for amplitude imbalance of ±1 dB and phase imbalance of ±8°. The size occupied by the proposed balun is 0.51 λg × 0.22 λg.


Rat-race coupler Balun Miniaturized balun Interdigital capacitor 


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Copyright information

© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  • Ankita Kumari
    • 1
    Email author
  • Tamasi Moyra
    • 1
  • Priyansha Bhowmik
    • 1
  1. 1.Department of Electronics and Communication EngineeringNational Institute of Technology AgartalaAgartala, West TripuraIndia

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