Modified Hairpin Filters Improving the Suppression Performance of Stop-Band

저지 대역 제거 특성을 향상시킨 변형된 헤어핀 여파기

  • Kim, Bong-Su (Electronics and Telecommunications Research Institute) ;
  • Kang, Min-Soo (Electronics and Telecommunications Research Institute) ;
  • Byun, Woo-Jin (Electronics and Telecommunications Research Institute) ;
  • Kim, Kwang-Seon (Electronics and Telecommunications Research Institute) ;
  • Song, Myung-Sun (Electronics and Telecommunications Research Institute)
  • Published : 2010.01.31


In this paper, a new hairpin type strip-line BPF(Band Pass Filter) improving the suppression performance of unwanted frequency signal is studied. A modified hairpin filter is designed by classical hairpin filter design methodology and is realized by newly placing structure of designed filter. And a newly formed coupled-line effects between modified bilateral symmetry structures make the transmission zeros. Each transmission zeros can shift its frequency to wanted frequency by tuning a certain part of filter. To investigate the validity of this novel technique, an order-5 Chebyshev BPF centered at 9.2 GHz with a 15 % FBW(fractional bandwidth) were used. According to design and measurement results, a good performance of insertion loss of 0.8 dB and unwanted signal suppression of maximum 50 dB is achieved at full input/output ports.




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