A compact symmetrical band-pass filter design using coupled microstrip line is presented in this paper. The microstrip line sections connected to the two input and output ports of the filter structure are printed over the Defected Ground Structure (DGS). The proposed symmetrical structure offers a simple and compact design and exhibits improved stop-band characteristics in comparison to the conventional coupled microstrip line filter structure. The prototype model of the proposed filter structure is developed and tested. The measured results are found to be in good agreement with the simulation results.
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