A New Design Approach for a Compact Microstrip Diplexer with Good Passband Characteristics
This paper presents an efficient theoretical design approach of a very compact microstrip diplexer for modern wireless communication system applications. The proposed basic resonator is made of coupled lines, simple transmission line and a shunt stub. The coupled lines and transmission line make a U-shape resonator while the shunt stub is loaded inside the U-shape cell to save the size significantly, where the overall size of the presented diplexer is only 0.008 λg2 . The configuration of this resonator is analyzed to increase intuitive understanding of the structure and easier optimization. The first and second resonance frequencies are f o1 = 895 MHz and f o2 = 2.2 GHz. Both channels have good properties so that the best simulated insertion loss at the first channel (0.075 dB) and the best simulated common port return losses at both channels (40.3 dB and 31.77 dB) are achieved. The presented diplexer can suppress the harmonics acceptably up to 3 GHz (3.3 fo1 ). Another feature is having 31% fractional bandwidth at the first channel.
Chen, C.F., Zhou, K.W., Chen, R.Y., Tseng, H.Y., He, Y.H., Li, W.J. and Weng, J.H., 2021. Design of microstrip multifunction integrated diplexers with frequency division, frequency selection, and power division functions. IEEE Access, 9, pp.53232-53242.
Dembele, S.N., Bao, J., Zhang, T. and Bukuru, D., 2019. Compact microstrip diplexer based on dual closed loop stepped impedance resonator. Progress in Electromagnetics Research C, 89, pp.233-241.
Fernandez-Prieto, A., Lujambio, A., Martel, J., Medina, F., Martin, F. and Boix, R.R., 2018. Balanced-to-balanced microstrip diplexer based on magnetically coupled resonators. IEEE Access, 6, pp.18536-18547.
Guan, X., Liu, W., Ren, B., Liu, H. and Wen, P., 2019. A novel design method for high isolated microstrip diplexers without extra matching circuit. IEEE Access, 7, pp.119681-119688.
Guan, X., Member, F., Yang, H., Liu, H. and Zhu, L., 2014. Compact and highisolation diplexer using dual-mode stub-loaded resonators. IEEE Microwave and Wireless Components Letters, 24(6), pp.385-387.
Hong, J.S. and Lancaster, M.J., 2001. Microstrip Filters for Rf/Microwave Applications. John Wiley and Sons, Hoboken.
Hussein, H.A., Mezaal, Y.S. and Alameri, B.M., 2021. Miniaturized microstrip diplexer based on fr4 substrate for wireless communications. Elektronika Ir Elektrotechnika, 27(5), pp.34-40.
Lu, Q.Y., Zhang, Y.J., Cai, J., Qin, W. and Chen, J.X., 2020. Microstrip tunable diplexer with separately-designable channels. IEEE Transactions on Circuits and Systems II: Express Briefs, 67(12), pp.2983-2987.
Majdi, K.A. and Mezaal, Y.S., 2022. Microstrip diplexer for recent wireless communities. Periodicals of Engineering and Natural Sciences, 10(1), pp.387-396.
Noori, L., Rezaei, A., 2017. Design of a microstrip dual-frequency diplexer using microstrip cells analysis and coupled lines components. International Journal of Microwave and Wireless Technologies, 9(7), pp.1467-1471.
Rezaei, A., Noori, L. and Mohammadi, H., 2019. Design of a miniaturized microstrip diplexer using coupled lines and spiral structures for wireless and WiMAX applications. Analog Integrated Circuits and Signal Processing, 98, pp.409-415.
Rezaei, A., Yahya, S.I., Noori, L. and Jamaluddin, M.H., 2019. Design of a novel wideband microstrip diplexer using artificial neural network. Analog Integrated Circuits and Signal Processing, 101(1), pp.57-66. doi: https://doi.org/10.1007/s10470-019-01510-1
Shirkhar, M.M. and Roshani, S., 2021. Design and implementation of a Bandpassbandpass diplexer using coupled structures. Wireless Personal Communications, 122(3), pp.2463-2477.
Su, Z.L., Xu, B.W., Zheng, S.Y., Liu, H.W. and Long, Y.L., 2020. High-isolation and Wide-stopband SIW diplexer using mixed electric and magnetic coupling. IEEE Transactions on Circuits and Systems II: Express Briefs, 67(1), pp.32-36.
Tahmasbi, M., Razaghian, F. and Roshani, S., 2021. Design of bandpassbandpass diplexers using rectangular-, T-, and Lshaped resonators for hybrid power amplifier and 5G applications. Analog Integrated Circuits and Signal Processing, 109(3), pp.585-597.
Yahya, S.I., Rezaei, A. and Nouri, L., 2020. Compact wide stopband microstrip diplexer with flat channels for WiMAX and wireless applications. IET Circuits, Devices and Systems, 14(6), pp.846-852. doi: https://doi.org/10.1049/iet-cds.2020.0010
Yousif, A.B. and Ezzulddin, A.S., 2020. A Dual-band coupled line based microstrip diplexer for wireless applications. Journal of Global Scientific Research, 10, pp.845-853.
Zhanga, C., Zhu, L. and Li, Y., 2018. Compact microstrip balanced-to-balanced diplexer using stub-loaded dual-mode resonators. IEICE Electronics Express, 15(5), pp.1-6.
Copyright (c) 2022 Abbas Rezaei, Salah I. Yahya
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License [CC BY-NC-SA 4.0] that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).