UMTS diplexer design using the antiparallel-coupled lines loaded with a stepped impedance resonator

Min Hua Ho, Wei Chen Lin

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3 Citations (Scopus)


We present a novel UMTS diplexer design using the filters of antiparallel-coupled lines structure loaded with a stepped impedance microstrip resonator. The diplexer is composed of two filters. And a microstrip line of quarter-wavelength is used to links each filter to the common port. The composing filters exhibit two tunable transmission zeros which are used to implement the mid-passband zero implantation for improving the isolation between the transmitting (Tx) and the receiving (Rx) ports. A pair of spurlines is used in the coupled lines of the Tx-filter to further increase the isolation. An experiment is conducted to assure the diplexer's performance and to verify the circuit design.

Original languageEnglish
Pages (from-to)2988-2990
Number of pages3
JournalMicrowave and Optical Technology Letters
Issue number12
Publication statusPublished - 2011 Dec 1


All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Condensed Matter Physics
  • Electrical and Electronic Engineering

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