Vol. 122

Latest Volume
All Volumes
All Issues

Stub Resonator Based Compact Low-Pass Filter (LPF) with Wide Harmonic Suppression

By Arpita Mandal and Tamasi Moyra
Progress In Electromagnetics Research C, Vol. 122, 31-40, 2022


In this article, an open T-shaped stub resonator-based compact microstrip low-pass filter (LPF) with low in-band insertion loss and wide attenuation band is proposed. The folded T-shaped stubs loaded with T-shaped open stubs are symmetrically embedded in the high impedance line of the microstrip structure. The proposed LPF operates at a cut-off frequency of 2.4 GHz, a roll-off factor (ROF) of 62 dB/GHz resonated up to -48.5 dB at the resonant frequency, and an insertion loss of 0.35 dB in the passband region. In the ground plane of the LPF, two dissimilar defected ground structures (DGS) are placed in the array to generate additional attenuation poles for enriching the performance of the stopband. The sixth harmonic suppression is achieved up to 14.6 GHz and relative stopband rejection of 144%. The EM simulated results show a well-matched behavior with the experimental ones. The proposed LPF can be used for Bluetooth, Wi-Fi (2400 MHz), and microwave oven (2450 MHz) applications.


Arpita Mandal and Tamasi Moyra, "Stub Resonator Based Compact Low-Pass Filter (LPF) with Wide Harmonic Suppression," Progress In Electromagnetics Research C, Vol. 122, 31-40, 2022.


    1. Hammed, R. T., S. H. Hassan, and S. L. Ajeel, "New compact Low-Pass Filter (LPF) using cascaded square open loop resonator," International Journal of Electronics and Communications (AEU), Vol. 92, 93-97, 2018.

    2. Hiedari, B. and F. Shama, "A harmonics suppressed microstrip cell for integrated applications," International Journal of Electronics and Communication (AEU), Vol. 83, 519-522, 2018.

    3. Hayati, M., M. Ekhteraei, and F. Shama, "Compact lowpass filter with flat group delay using lattice-shaped resonator," Electronics Letters, Vol. 53, No. 7, 475-476, 2017.

    4. Karthikeyan, S. S. and R. S. Kshetrimayum, "Compact and wide stopband lowpass filter using open complementary split ring resonator and defected ground structure," Radio Engineering, Vol. 24, No. 3, 708-711, 2015.

    5. Liu, S., J. Xu, and Z. Xu, "Compact lowpass filter with wide stopband using stepped impedance hairpin units," Electronics Letters, Vol. 51, No. 1, 67-69, 2015.

    6. Chen, X., L. Zhang, Y. Peng, Y. Leng, H. Lu, and Z. Zheng, "Compact lowpass filter with wide stopband bandwidth," Microwave and Optical Technology Letters, Vol. 57, No. 2, 367-371, 2015.

    7. Ellatif, W. A. and A. Boutejdar, "Design of low-pass filter using meander inductor and U-form Hi- Lo topology with high compactness factor for L-band applications," Progress In Electromagnetics Research M, Vol. 55, 95-107, 2017.

    8. Huang, S. Y. and Y. H. Lee, "Compact stepped-impedance lowpass filter with a slot-back microstrip line," Microwave and Optical Technology Letters, Vol. 50, No. 4, 1059-1061, 2008.

    9. Du, Z., H. Yang, H. Zhang, and M. Zhu, "Compact lowpass filter with high suppression level and wide stop-band using stepped impedance m-shape units," Microwave and Optical Technology Letters, Vol. 56, No. 12, 2947-2950, 2014.

    10. Kchairi, A. B., M. Boussouis, and N. A. Touhami, "High-performance LPF using coupled C-shape DGS and radial stub resonators for microwave mixer," Progress In Electromagnetics Research Letters, Vol. 58, 97-103, 2016.

    11. Rekha, T. K., P. Abdulla, P. M. Raphika, and J. P. Muhammed, "Compact microstrip lowpass filter with ultra-wide stopband using patch resonators and open stubs," Progress In Electromagnetics Research C, Vol. 72, 15-28, 2017.

    12. Wang, J., H. Cui, and G. Zhang, "Design of compact microstrip lowpass filter with ultra-wide stopband," Electronics Letters, Vol. 48, No. 14, 854-856, 2012.

    13. Sen, S., T. Moyra, and D. Sarkar, "Modelling and validation of microwave LPF using modified rectangular Split Ring Resonators (SRR) and defected structures," AEU --- International Journal of Electronics and Communications, Vol. 88, 1-10, 2018.

    14. Boutejdar, A. and W. A. E. Ali, "Improvement of compactness of low pass filter using new quasi Yagi-DGS-resonator and multilayer-technique," Progress In Electromagnetics Research C, Vol. 69, 115-124, 2016.

    15. Huang, S. Y. and Y. H. Lee, "A compact E-shaped patterned ground structure and its applications to tunable bandstop resonator," IEEE Transactions on Microwave Theory and Techniques, Vol. 57, No. 3, 657-665, 2009.

    16. Shi, L.-F., Z.-Y. Fan, and D. J. Xin, "Miniaturized low-pass filter based on defected ground structure and compensated microstrip line," Microwave Optical Technology Letters, Vol. 62, No. 3, 1093-1097, 2019.

    17. Mandal, A. and T. Moyra, "Stepped Impedance Hairpin Resonator (SIHR) based compact lowpass filter with wide attenuation band," Electromagnetics, Vol. 42, No. 1, 2022.

    18. Choudhary, D. K. and R. K. Chaudhary, "Compact lowpass and dual-band bandpass filter with controllable transmission zero/center frequencies/passband bandwidth," IEEE Transactions on Circuits and Systems II: Express Briefs, Vol. 67, No. 6, 1044-1048, 2020.

    19. Hong, J.-S. and M. J. Lancaster, Microstrip Filters for RF/Microwave Applications, 157-158, John Wiley & Sons, Inc., 2001.