Investigation of new dual-mode triangular-patch bandpass filters using spur-lines.

Without any perturbations on the surface of the patch resonator or orthogonal feed lines, new microstrip dual-mode triangular-patch bandpass filters are presented in this article. The degenerate modes are excited by the use of the spur-lines for input/output microstrip lines. Also, the influence of design parameters on the frequency characteristics of the proposed dual-mode filters is discussed. In addition, a modified dual-mode filter using double-spur-lines is introduced and simulated. Measurement verifies the validity of the introduced design method. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2100–2103, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21880 [ABSTRACT FROM AUTHOR]