Design of Microstrip Parallel-Coupled Lines with High Directivity using Symmetric-Centered Inductors

Authors

  • Somchat Sonasang Department of Electrical Engineering, Faculty of Engineering, Mahasarakham University Maha Sarakham 44150, Thailand
  • Niwat Angkawisittpan Research Unit for Computational Electromagnetics and Optical Systems, Faculty of Engineering Mahasarakham University, Maha Sarakham 44150, Thailand

Keywords:

Microstrip, parallel-coupled lines, directivity, symmetric-centered inductors

Abstract

A technique for directivity improvement of the microstrip parallel-coupled lines using symmetriccentered inductors is presented in this paper. The design procedure of the symmetric-centered inductors using the closed-form equations is given. The proposed technique was performed with a design at the operating frequency of 0.9 GHz on an FR4 substrate. Validity of the proposed technique is verified by simulations and measurements in comparisons with conventional parallel-coupled lines. The measured results exhibit the isolation of -30.10 dB and directivity of 19.28 dB at the operating frequency of 0.9 GHz. The directivity from the measured results is improved by more than 4 dB at 0.9 GHz and more than 6 dB at 1.05 GHz compared with the conventional parallel-coupled lines. In addition, the proposed technique for the microstrip parallel-coupled line can achieve a high directivity with the compact size (21.0 mm x 4.70 mm). The novelty of this paper is by introducing the proposed and closed-form design equations for the compact symmetric-centered inductors with high directivity.

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Author Biographies

Somchat Sonasang, Department of Electrical Engineering, Faculty of Engineering, Mahasarakham University Maha Sarakham 44150, Thailand

Somchat Sonasang was born in Nong Bua Lam Phu Province, Thailand on October, 27, 1982. He received a B.Eng. from Rajamangala University of Technology Isan (RMUTI), Nakhon Ratchasima, Thailand in 2006, and an M.Eng. from Khon Kaen University (KKU), Khon Kaen, Thailand in 2013. He is currently working towards a Ph.D. at Mahasarakham University (MSU), Maha Sarakham, Thailand. His current research interests include microwave circuits and non-destructive tests.

Niwat Angkawisittpan, Research Unit for Computational Electromagnetics and Optical Systems, Faculty of Engineering Mahasarakham University, Maha Sarakham 44150, Thailand

Niwat Angkawisittpan was born in Khon Kaen, Thailand. He received his B.Eng. in Electrical Engineering with honors from Khon Kaen University, Thailand in 1997. He received his M.Sc. in Electrical & Computer Engineering from Purdue University, Indiana, USA in 2003. He received his Ph.D. in Electrical Engineering from University of Massachusetts Lowell, Massachusetts, USA in 2009. Since 2009, he has been with the Research Unit for Computational Electromagnetics and Optical Systems (CEMOS), Faculty of Engineering, Mahasarakham University, Maha Sarakham, Thailand as a Lecturer. He has authored or co-authored several papers in scientific journals and conference proceedings. His research interests include compact microstrip devices, metamaterial applications for RF and microwave circuits, and electromagnetic material characterization.

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Published

2021-11-04

How to Cite

[1]
S. . Sonasang and N. . Angkawisittpan, “Design of Microstrip Parallel-Coupled Lines with High Directivity using Symmetric-Centered Inductors”, ACES Journal, vol. 36, no. 06, pp. 657–663, Nov. 2021.

Issue

2021: Vol 36 Iss 6

Section

Articles