A simple and flexible differential negative group delay (NGD) circuit topology based on defected ground structure (DGS) is proposed. The circuit consists of microstrip lines and reverse nested double U-shaped (RNDU) DGSs, in which differential transmission and common-mode suppression (CMS) are realized by microstrip lines, and the adjustment of NGD time and the center frequency is achieved by changing the RNDU DGSs. Besides, the bandwidth and NGD time can be increased by cascading double couples of RNDU DGSs. For demonstration, two circuit prototypes with single- and double-couple DGSs are fabricated and measured. The measured results show that the NGD time of the single-couple DGS circuit at the center frequency of 2.279 GHz is -0.57 ns; the insertion loss is 2.08 dB; and the NGD bandwidth is 28 MHz. The NGD time of the double-couple DGS circuit at 2.30 GHz is -2.13 ns; the NGD bandwidth is 41 MHz; and the insertion loss is 4.39 dB. The functions of increasing bandwidth and enhancing NGD are realized. The common-mode insertion loss can reach 43.2 dB, and excellent CMS characteristics are achieved.
2. Feng, W., W. Che, and Q. Xue, "New balance-applications for dual-mode ring resonators in planar balanced circuits," IEEE Microw. Mag., Vol. 20, No. 7, 15-23, Jul. 2019.
doi:10.1109/MMM.2019.2909519
3. Li, L., L.-S. Wu, J. Mao, M. Tang, and X.-W. Gu, "A balanced-to-balanced rat-race coupling network based on defected slots," IEEE Microwave Wireless Compon. Lett., Vol. 29, No. 7, 459-461, Jul. 2019.
doi:10.1109/LMWC.2019.2915951
4. Shi, J., J. Ren, J. Dong, W. Feng, and Y. Yang, "Supercompact balanced wideband bandpass filter using capacitor-loaded three-line coupled structure," IEEE Microwave Wireless Compon. Lett., Vol. 32, No. 6, 499-502, Jun. 2022.
doi:10.1109/LMWC.2022.3141123
5. Azizzadeh, A. and L. Mohammadi, "Degradation of BER by group delay in digital phase modulation," Fourth Advanced International Conference on Telecommunications, 350-354, Jun. 2008.
6. Myoung, S.-S., Y.-H. Kim, and J.-G. Yook, "Impact of group delay in RF BPF on impulse radio systems," IEEE MTT-S International Microwave Symposium, 1891-1894, Jun. 2005.
7. Gu, T., J. Chen, B. Ravelo, F. Wan, V. Mordachev, and Q. Ji, "Quad-band NGD investigation on crossed resonator interconnect structure," IEEE Trans. Circuits Syst. II, Exp. Briefs, Vol. 69, No. 12, 4789-4793, Dec. 2022.
8. Wan, F., et al., "Design and experimentation of inductorless low-pass NGD integrated circuit in 180-nm CMOS technology," IEEE Trans. Comput. Aided Des. Integr. Circuits Syst., Vol. 41, No. 11, 4965-4974, Nov. 2022.
doi:10.1109/TCAD.2021.3136982
9. Gu, T., F. Wan, J. Chen, B. Ravelo, and X. Zhao, "Compact and wideband flat negative group delay circuit investigation," IEEE Trans. Circuits Syst. II, Exp. Briefs, Early Access, 2023.
10. Chen, Z., J. Shi, and K. Xu, "Negative group delay power dividing network with balanced-to-single-ended topology," IET Microw. Antennas Propag., Vol. 13, No. 10, 1705-1710, Aug. 2019.
doi:10.1049/iet-map.2018.6092
11. Zhu, Z., Z. Wang, S. Zhao, H. Liu, and S. Fang, "A novel balanced-to-unbalanced negative group delay power divider with good common-mode suppression," Int. J. RF Microw. Comput. Aided Eng., Vol. 32, No. 7, e23173, Jul. 2022.
12. Zhou, X., et al., "Analytical design of dual-band negative group delay circuit with multi-coupled lines," IEEE Access, Vol. 8, 72749-72756, 2020.
doi:10.1109/ACCESS.2020.2988096
13. Wan, F., N. Li, B. Ravelo, N. M. Murad, and W. Rahajandraibe, "NGD analysis of turtle-shape microstrip circuit," IEEE Trans. Circuits Syst. II, Exp. Briefs, Vol. 67, No. 11, 2477-2481, Nov. 2020.
14. Wang, Z., Y. Bai, Y. Meng, S.-J. Fang, and H. Liu, "A compact negative group delay circuit topology based on asymmetric coplanar striplines and double-sided parallel striplines," Progress In Electromagnetics Research Letters, Vol. 98, 139-144, 2021.
doi:10.2528/PIERL21053003
15. Zhu, Z., Z. Wang, Y. Meng, S. Fang, and H. Liu, "Balanced microstrip circuit with differential negative group delay characteristics," Cross Strait Radio Science and Wireless Technology Conference, 257-259, Oct. 2021.
16. Wang, Z., S. Zhao, H. Liu, and S. Fang, "A compact dual-band differential negative group delay circuit with wideband common mode suppression," IEEE J. Microw., Vol. 2, No. 4, 720-725, Oct. 2022.
doi:10.1109/JMW.2022.3192114
17. Li, L., J. Mao, M. Tang, and H. Dai, "Mixed-mode property of defected ground structure and its application in balanced network design with harmonic suppression," IEEE Microwave Wireless Compon. Lett., Vol. 28, No. 3, 188-190, Mar. 2018.
doi:10.1109/LMWC.2018.2797523
18. Mouris, B. A., A. Fernandez-Prieto, R. Thobaben, J. Martel, F. Mesa, and O. Quevedo-Teruel, "Glide symmetry to improve the bandgap operation of periodic microstrip defected ground structures," European Microwave Conference, 483-486, Jan. 2021.
19. Chaudhary, G., J. Jeong, P. Kim, Y. Jeong, and J. Lim, "Compact negative group delay circuit using defected ground structure," Asia-Pacific Microwave Conference, 22-24, Nov. 2013.
20. Chaudhary, G., Y. Jeong, and J. Lim, "Miniaturized dual-band negative group delay circuit using dual-plane defected structures," IEEE Microwave Wireless Compon. Lett., Vol. 24, No. 8, 521-523, Aug. 2014.
doi:10.1109/LMWC.2014.2322445
21. Ji, Q., et al., "CSRR DGS-based bandpass negative group delay circuit design," IEEE Access, Vol. 11, 20309-20318, 2023.
doi:10.1109/ACCESS.2023.3249968
22. Park, J., J. Kim, J. Lee, S. Kim, and S. Myung, "A novel equivalent circuit and modeling method for defected ground structure and its application to optimization of a DGS lowpass filter," IEEE MTT-S International Microwave Symposium, 417-420, Jun. 2002.
23. Kandic, M. and G. E. Bridges, "Negative group delay prototype filter based on cascaded second order stages implemented with Sallen-Key topology," Progress In Electromagnetics Research B, Vol. 94, 1-18, 2021.
doi:10.2528/PIERB21071209
Submit
