scispace - formally typeset
Search or ask a question
Proceedings ArticleDOI

Design of bandpass filter using star loop dual mode resonator

02 Apr 2015-pp 0238-0241
TL;DR: This paper presents bandpass filter designs using a star type loop resonator, which exhibits elliptic response having transmission zeros on either side of the center frequency which improves the selectivity of the filter.
Abstract: This paper presents bandpass filter designs using a star type loop resonator. Both single mode and dual mode microstrip filters are designed. A small triangular patch element is used to perturb the fields and couple the dual degenerate modes for constructing dual mode bandpass filter. Two single mode filters are designed and results show chebyshev like characteristics. The dual mode filter exhibits elliptic response having transmission zeros on either side of the center frequency which improves the selectivity of the filter. The respective electric field patterns generated by the full wave simulator are given. The first single mode filter designed shows an insertion loss of 1 dB and return loss of 18.5 dB at 4.1 GHz, with fractional bandwidth (FBW) of 4.87%. The second single mode filter gives an insertion loss of 1 dB and return loss of 22.5 dB at 4.15 GHz with FBW of 6.097%. The dual mode filter achieves an insertion loss of 2 dB and return loss of 34 dB at 4.1 GHz with FBW of 4.93%.
Citations
More filters
Journal ArticleDOI
TL;DR: In this article, a modified star-shaped dual-mode microstrip loop resonator with a triangular patch is proposed to design compact narrow band band bandpass filters with transmission zeros.
Abstract: A modified star-shaped dual-mode microstrip loop resonator with a triangular patch is proposed to design compact narrow band bandpass filters with transmission zeros. The triangular patch is used as perturbation element to couple degenerated modes. The position of transmission zeros can be tuned by varying the size and location of the perturbation element. The coupling mechanism (inductive or capacitive) and the type of input/output feed (orthogonal or non-orthogonal) determine the type of filter response like symmetric or asymmetric. Three highly selective two-pole narrow band bandpass filters are designed using a modified star-shaped resonator with tunable transmission zeros. First, two filters with non-orthogonal feed lines have an asymmetric response with transmission zeros on one side of the passband, whereas the third filter with orthogonal feed lines exhibits symmetric frequency response with transmission zeros on both sides of the passband. Even and odd mode analysis is applied to the dual-mode filters to calculate the position of transmission zeros. Filters are realized using a low loss dielectric substrate, and measured results are in good agreement with the theoretical and simulated ones.

5 citations


Cites methods from "Design of bandpass filter using sta..."

  • ...In this paper, highly selective narrow bandpass filters are designed using a modified star-shaped microstrip loop resonator [10] with dual degenerate modes which employ both orthogonal and nonorthogonal feed lines....

    [...]

References
More filters
Journal ArticleDOI
TL;DR: In this article, two degenerate modes can be excited on a microstrip ring resonator to realize a double-tuned circuit bandpass filter in microstrip technique, which can be used to achieve a better performance than the conventional bandpass filters.
Abstract: It is shown that two degenerate modes can be excited on a microstrip ring resonator. These modes can be used to realise a double-tuned circuit bandpass filter in microstrip technique.

553 citations

Journal ArticleDOI
TL;DR: In this article, the authors report on the results of an investigation into dual-mode operation of microstrip triangular patch resonators and their applications for designing dualmode bandpass filters.
Abstract: In this paper, we report on the results of an investigation into dual-mode operation of microstrip triangular patch resonators and their applications for designing dual-mode bandpass filters. It has been found theoretically that the dual modes can result from the rotation and superposition of a fundamental mode. The characteristics of the dual modes and their mode splitting are described. The applications of this new type of dual-mode microstrip patch resonator in the design of microwave planar filter are presented. A circuit model for operation of this type of filter is proposed. Two- and four-pole filters of this type are demonstrated for the first time. Both theoretical and experimental results are presented.

270 citations

Journal ArticleDOI
TL;DR: In this paper, a dual-mode microstrip bandpass filter using degenerate modes of a meander loop resonator has been developed for miniaturization of high selectivity narrow-band microwave bandpass filters.
Abstract: A novel type of dual-mode microstrip bandpass filter using degenerate modes of a meander loop resonator has been developed for miniaturization of high selectivity narrow-band microwave bandpass filters. A filter of this type having a 2.5% bandwidth at 1.58 GHz was designed and fabricated. The measured filter performance is presented. >

258 citations


"Design of bandpass filter using sta..." refers background in this paper

  • ...Various dual mode resonators have been studied by many researchers such as circular ring [2], the meander loop [3], the circular disk, square patch [4], and the triangular patch [5]....

    [...]

Journal ArticleDOI
Adnan Görür1
TL;DR: In this paper, a dual-mode resonator with square-patch or corner-cut elements located at four corners of a conventional microstrip loop resonator is proposed, where one of these patches or corner cuts is called the perturbation element, while the others are called reference elements.
Abstract: A novel dual-mode resonator with square-patch or corner-cut elements located at four corners of a conventional microstrip loop resonator is proposed. One of these patches or corner cuts is called the perturbation element, while the others are called reference elements. In the proposed design method, the transmission zeros are created or eliminated without sacrificing the passband response by changing the perturbation's size depending on the size of the reference elements. A simple transmission-line model is used to calculate the frequencies of the two transmission zeros. It is shown that the nature of the coupling between the degenerate modes determines the type of filter characteristic, whether it is Chebyshev or elliptic. Finally, two dual-mode microstrip bandpass filters are designed and realized using degenerate modes of the novel dual-mode resonator. The filters are evaluated by experiment and simulation with very good agreement.

248 citations


"Design of bandpass filter using sta..." refers background in this paper

  • ...The size, shape and arrangement [6] of the perturbation element decides whether the filter is chebyshev or elliptic....

    [...]

Proceedings ArticleDOI
10 Jul 1991
TL;DR: A new generation of planar dual mode filters is introduced which offers significant size, weight, and cost advantages over previous designs, and may be used to replace bulkier, heavier filters currently used for satellite communications.
Abstract: A new generation of planar dual mode filters is introduced which offers significant size, weight, and cost advantages over previous designs. All currently used elliptic function, self-equalized, etc. filter designs can be implemented in microstrip using this new concept. The proposed filter structures are ideally suited for implementation using high-temperature superconductors. Basic dual mode resonator and filter structures are discussed, and experimental data for proof-of-concept filters implemented using both normal and superconducting microstrip are presented. Superconducting realizations of this class of filters may be used to replace bulkier, heavier filters currently used for satellite communications. >

192 citations