Miniaturized Bandstop Filter Using MeanderSpurline and Capacitively Loaded Stubs

ETRI Journal

关键词: circuit modeling;    bandgap;    slow-wave;    meander spurline;    Bandstop filter;   

Others  :  1185510
DOI  :  10.4218/etrij.07.0107.0077

【 摘 要 】

A miniaturized bandstop filter (BSF) is introduced in this paper.The filter consists of one meander spurline and a pair of capacitively loaded stubs. The meander spurline with low resonant frequency and improved slow-wave factor exhibits excellent resonant bandgap characteristics which can be modeled by a longitudinally coupled resonator. The design of the proposed microstrip BSF is presented, and its performance is measured. Measurements show that there is a stopband from 2.3 to 5.6 GHz with S21 less than –20 dB. The total length of this BSF equals 23 mm.

   

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