A novel X-band broadband bandstop filter with sharp cut-off frequency using EBG dual-ear structures

• Published in: Microwave and optical technology letters Vol. 53; no. 7; pp. 1671 - 1674
• Main Authors: Huang, J.-M., Zhu, H. Z., Han, K., Guo, H.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.07.2011
• Subjects: Band-stop filters (BSF); Bandstop filters; Bandwidth; Broadband; coplanar waveguide (CPW); electromagnetic bandgap (EBG); insertion loss; Microwaves; Proposals; Reproduction; Ripples; X-band
• ISSN: 0895-2477; 1098-2760; 1098-2760
• DOI: 10.1002/mop.26031

A novel X‐band broadband bandstop filter (BSF) with sharp cut off frequency is presented, using novel design of periodic electromagnetic bandgap (EBG) dual‐ear (DE) structures on coplanar waveguide (CPW) transmission line. An equivalent lumped circuit is introduced to model the BSF with EBG‐DE structures. The stopband of this filter is ranged within X‐band to have sharp selectivity and deep attenuation levels. The 3‐dB bandwidth of the BSF is 4.2 GHz, from 8.6 to 12.8 GHz and the center frequency is 11.5 GHz. The 20‐dB bandwidth is 2 GHz, from 9.9 to 11.9 GHz. In 20‐dB stop‐band range, the ripple of return loss is less than 0.05 dB.The proposal BSF is fabricated using the surface micromachining, and the measurement and simulation results coincided well. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26031