COMPACT ODD-ORDER BAND-PASS FILTERS USING CAPACITIVELY COUPLED SPIRAL RESONATORS

In this article, a new topology for designing compact, band-pass filters of odd-order (N = 3, 5, 7, ...) is presented. The technique is based oil using resonators with parallel RLC type resonance with high loaded quality factor (Q(L)) in conjunction with the capacitively loaded, slow-wave transmission lines. Using the approach presented in this article compact band-pass filters with bandwidths as small as 5% to as wide as 50% call easily be designed. The principles of operation of the proposed filter along with experimental results of several different fabricated prototypes are presented and discussed in this article. (C) 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 3172-3175, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.2392