Compact Narrow Band Non-Degenerate Dual-Mode Microstrip Filter with Etched Square Lattices

P. K. Singhal, S. Mathur, R. N. Baral

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DOI: 10.4236/jemaa.2010.22014                

Abstract

A compact narrowband non-degenerate dual-mode microstrip filter with square shape cuts is presented. The structure is developed by loading the conventional non-degenerate dual-mode resonator by open circuit stubs at two opposite corners. The filter bandwidth is controlled by only decreasing the higher cutoff frequency of the conventional type. With Square shape cuts, return loss is improved. A 20% fractional bandwidth filter is designed and implemented on FR4 material with 4.4 dielectric constant and 1.6 mm thickness at center frequency of 1.5 GHz with passband of 1.3 GHz to 1.6 GHz. Analysis has been achieved using the IE3D simulator. Experimental results do agree with simulations.

Keywords

Microstrip, Dual Mode, Narrowband Filter, Square Patch Resonator

Conflicts of Interest

The authors declare no conflicts of interest.

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