Miniaturized band-stop filter based on multilayer-technique and new coupled octagonal defected ground structure with interdigital capacitor

✍ Scribed by A. Boutejdar; A. Abdel-Rahman; A. Batmanov; P. Burte; A. Omar

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 532 KB
• Volume: 52
• Category: Article
• ISSN: 0895-2477
• DOI: 10.1002/mop.24967

✦ Synopsis

Abstract

In this article, we proposed a new compact defected ground structure (DGS) band‐stop filter with broad passband and low insertion loss in the stop‐band. The philosophy of the structure behind this new microstrip band‐stop filter is simple as it is composed of a pair of octagonal DGS‐slots and an open‐stub as compensated microstrip capacitance. The filter will be realized through direct electromagnetic coupling and slow wave effect methods. With this configuration, the BSF with higher compactness, broad passband and sharp transition characteristics was realized. The design formulas are derived by using an equivalent‐circuit model of a parallel L‐C resonator. Finally, an interdigital‐capacitor has been designed and included in the DGS‐ring‐element. Better compactness of the structure and symmetry of the frequency response have been achieved as well as two reflection zeros closed to the stopband have been obtained. Thus, a selectivity of the proposed filter has been improved. To validate the feasibility of the proposed design method, both band‐stop filters are designed, fabricated, and measured. The experimental results agree well with the simulation results. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 510–514, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24967