• A. Rezaei
  • S. I. Yahya
  • L. Noori
  • M. H. Jamaluddin



Compact, Coupled lines, Diplexer, Microstrip


In this paper, a novel miniaturized microstrip diplexer using two bandpass filters (BPFs) is designed and fabricated. The filters consist of stub loaded coupled lines. Additional stubs and T-shape feeding structures are added to miniaturize the size of the presented diplexer. With the adopted special structure, low insertion losses and compact size are obtained. The introduced diplexer operates at 2.12 GHz for WCDMA application and 3.94 GHz for WiMAX application. The obtained insertion losses are 0.25 dB at 2.12 GHz and 0.26 dB at 3.94 GHz. A design technique for analyzing the proposed resonator is introduced to tune the resonance frequencies and obtain a compact size. The size of the proposed diplexer is 23.4 × 16.9 mm2 (0.038 λg2). The measurement result of the fabricated diplexer validates the design technique and simulation results. 


[1] M. Salehi, L. Noori, "Miniaturized Microstrip Bandpass Filters Using Novel Stub Loaded Resonator," Applied
Computational Electromagnetics Society (ACES), vol. 30, no. 6, pp. 692-697, 2015.
[2] W-H. Tuand W-C. Hung, "Microstrip Eight-Channel Diplexer with Wide Stopband," IEEE Microw. Wirel. Compon.
Lett., vol. 24, no. 11, pp. 742-744, 2014.
[3] N. Edward, Z. Zakaria, N.A. Shairi, “Reconfigurable Feeding Network with Dual-band Filter for WiMAX Application,”
International Journal of Electrical and Computer Engineering (IJECE), vol. 7, no. 5, pp. 2411-2419, 2017.
[4] A. Boutejdar, M. Amzi, S.D. Bennani, “Design and Improvement of a Compact Bandpass Filter using DGS Technique
for WLAN and WiMAX Applications,” TELKOMNIKA, vol. 15, no. 3, pp. 1137-1144, 2017.
[5] I. Zahraoui, A. Errkik, M.C. Abounaima, A. Tajmouati, L.E. Abdellaoui, M. Latrach, “A New Planar Multiband
Antenna for GPS, ISM and WiMAX Applications,” International Journal of Electrical and Computer Engineering
(IJECE), vol. 7, no. 4, pp. 2018-2026, 2017.
[6] L. Noori and A. Rezaei, "Design of a Microstrip Diplexer with a Novel Structure for WiMAX and Wireless
Applications, " AEÜ - International Journal of Electronics and Communications, vol. 77, pp.18–22, 2017.
[7] A. Rezaei, L. Noori, H. Mohammadi, "Design of a novel compact microstrip diplexer with low insertion loss," Microw
Opt Technol Lett., vol. 59, no. 7, pp.1672-1676, 2017.
[8] S. Theerawisitpong, P. Pinpathomrat, "A Microstrip Diplexer Using Folded Single Stepped Impedance Resonator for
3G Microcell Stations," International Journal of Information and Electronics Engineering, vol. 6, no. 3, pp.171-174,
[9] A. Chinig, J. Zbitou, A. Errkik, L. Elabdellaoui, A. Tajmouati, A. Tribak and M. Latrach, "A New Microstrip Diplexer
Using Coupled Stepped Impedance Resonators," International Journal of Electrical Computer Energetic Electronic and
Communication Engineering, vol. 9, no. 1, pp. 41-44, 2015.
[10] F. Cheng, X. Lin, K. Song, Y. Jiang, and Y. Fan, "Compact Diplexer With High Isolation Using the Dual-Mode
Substrate Integrated Waveguide Resonator," IEEE Microw. Wirel. Compon. Lett., vol. 23, no. 9, pp. 459-461, 2013.
[11] Q. Duan, K. Song, F. Chen and Y. Fan, "Compact wide-stopband diplexer using dual mode resonators," Electron. Lett.,
vol. 51, no. 14, pp. 1085-1087, 2015.
[12] K. Lu, G-M. Wang, H-Y. Xu, X. Yin, "Design of Compact Planar Diplexer Based on Novel Spiral-Based Resonators,"
Radioengineering, vol. 21, no. 1, pp. 528-532, 2012.
[13] J. Shi, J-X. Chen, Z-H. Bao, "Diplexers Based on Microstrip Line Resonators with Loaded Elements," Progress In
Electromagnetics Research, vol. 115, pp. 423-439, 2011.
[14] M.R. Salehi, S. Keyvan, E. Abiri, L. Noori, "Compact microstrip diplexer using new design of triangular open loop
resonator for 4G wireless communication systems, “AEÜ - International Journal of Electronics and Communications,
vol. 70, no. 7, pp. 961-969, 2016.
[15] H. L-Morales, J.S. Sun, A. C-Chavez, T. Itoh, J. L-Cervantes, " Novel microstrip diplexer for ultra-wide-band (UWB)
and wireless LAN (WLAN) bands," Journal of Electromagnetic Waves and Applications, vol. 27, pp. 1338-1350, 2013.
[16] F. Yang, X. Guan, L. Zhu, H. Liu, “Compact Microstrip Diplexer for 4G Wireless Communication," Progress In
Electromagnetics Research, vol. 25, pp. 599-602, 2014.
[17] J-M. Yan, H-Y. Zhou, L-Z. Cao, "Compact diplexer using microstrip half- and quarter-wavelength resonators," IET
Electronics Letters, vol. 25, no. 19, pp. 1613-1615, 2016.
[18] X. Guan, F. Yang, H. Liuand L. Zhu, "Compact and High-Isolation Diplexer Using Dual-Mode Stub-Loaded
Resonators, " IEEE Microw. Wirel. Compon. Lett., vol. 24, no. 6, pp. 385-387, 2014.
[19] J-S. Hong, MJ. Lancaster, “Microstrip Filters for RF/Microwave Applications,” A Wiley-Inter Science Publication, 2nd
Edition 2011, 2011.




How to Cite

A. Rezaei, S. I. Yahya, L. Noori, & M. H. Jamaluddin. (2020). DESIGN AND FABRICATION OF A NOVEL COMPACT LOW-LOSS MICROSTRIP DIPLEXER FOR WCDMA AND WIMAX APPLICATIONS. Journal of Microwaves, Optoelectronics and Electromagnetic Applications (JMOe), 18(4), 482–491.



Regular Papers