Improved circuit model for DGS based lowpass filter

A new microstrip low pass filter (LPF) with defected ground structure (DGS) is proposed in this article.The DGSs consists of reshaped rectangular dumbbell slot and four groups of Z‐shape slots. The microstrip line with DGS gave good rejection band extend from 3.0 to 9 GHz with acceptable pass band. The microstrip line with open circuit stubs (without DGS) gave good rejection band at the high frequency from 9 to 14 GHz. Using both structures results in LPF with wideband rejection from 3.37 to 14 GHz with attenuation less than (−26.0dB) and good passband less than (−25 dB). An equivalent circuit for the proposed LPF was given. The realized filter size was 34.0 × 34.0 mm2, and it gave good agreement with simulated results. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:811–815, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25876

Section: Simulation Of Lpf With Dgsmentioning

confidence: 99%

Microstrip low pass filter with wideband rejection using opened circuit stubs and Z‐slots defected ground structures

Mohra

2011

“…On the other hand for the conventional filter, the stopband width with 20 dB attenuation reaches only 4.5 GHz. Moreover, the proposed filter is 50% smaller than the conventional end-coupled filter [7][8][9]. The new DGS-bandpass filter [10][11][12] was fabricated and its measuredand simulated results are shown in Figures 14 and 15.…”

Section: Compact End-coupled Bpf Using Dgs-slotsmentioning

confidence: 99%

A novel compact J‐admittance inverter‐coupled microstrip bandpass filter using arrowhead‐shape as defected ground structure

Boutejdar

Amari

Omar

2009

This letter reports a new design of compact end‐coupled microstrip bandpass filter with two arrowhead slots as defected ground structure (DGS) in the ground plane [Boutejdar etal., IEEE AP‐SSymp (2005); Ahn, IEEE Trans Microwave Theory Tech 27 (1979), 44–50; Won etal., IEEE Trans Microwave Theory Tech 49 (2001), 86–93]. These slots replaced two λ/2‐microstrip resonators. Both feeds are indirectly coupled with the resonator on top layer by means of a J12 ‐admittance inverter (gap g). This method gives an advantage of size reduction over the conventional design by more than 50%, this structure allows for a convenient method to control the center‐frequency and high suppression of harmonics. From 6 to 14 GHz, the investigated DGS‐BPF has a rejection level better than 20 dB. According to design and measurement results, a good agreement between simulated and measured results is achieved. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 34–38, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24817

“…In those applications, the key issue is to obtain a simple and accurate circuit model to attain optimized design with an aimed performance. Some equivalent circuit models have been presented and these efforts have provided improved design methods and physical insight into the operation principle of the DGSs .…”

Section: Introductionmentioning

confidence: 99%

A modeling method for dumbbell‐shaped DGS and its parameter extraction

Woo

Lee

Nam

2014

This article presents an equivalent circuit model for a dumbbell‐shaped defected ground structure (DGS) in a microstrip line. The effects of equivalent circuit elements of a dumbbell‐shaped DGS and their magnetic coupling to the host transmission line are modeled as a simple lumped‐element circuit. By adding a virtual capacitor on the narrow etched gap, the values of inductance and capacitance of the dumbbell‐shaped DGS in the ground plane were extracted. Also, other main circuit parameters of the proposed circuit model were extracted using EM simulation result. This article provides one approach for understanding the operating principle of the DGS structures. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2910–2913, 2014