A compact ultra-wideband (UWB) bandpass filter (BPF) is proposed based on end coupled microstrip transmission line, defected ground structure and defected microstrip structure. The experimental filter shows a fractional bandwidth of 110% at a centre frequency, with two observable transmission zeros (attenuation poles) at 2.1 and 11.7 GHz. Measured results exhibit an UWB passband from 3.02 to 10.6 GHz with mid-band insertion loss of 1.8 dB and group delay variation <0.45 ns. The BPF achieves a wide stopband with < −18 dB attenuation up to 20 GHz.

References

1. 1)
  - 6. Wang, H., Zhu, L.: ‘Ultra-wideband bandpass filter using back-to-back microstrip-to-CPW transition structure’, Electron. Lett., 2005, 41, (24), pp. 1337–1338 (doi: 10.1049/el:20053466).
2. 2)
  - 4. Zhu, L., Wang, H.: ‘Ultra-wideband bandpass filter on aperture-backed microstrip line’, Electron. Lett., 2005, 41, (18), pp. 1015–1016 (doi: 10.1049/el:20052317).
3. 3)
  - 8. Abbosh, A.M.: ‘Design method for ultra-wideband bandpass filter with wide stopband using parallel-coupled microstrip lines’, IEEE Trans. Microw. Theory Tech., 2012, 60, (1), pp. 31–38 (doi: 10.1109/TMTT.2011.2175241).
4. 4)
  - 5. Yang, G.M., Jin, R.H., Geng, J.P.: ‘Planar microstrip UWB bandpass filter using U-shaped slot coupling structure’, Electron. Lett., 2006, 42, (25), pp. 1461–1463 (doi: 10.1049/el:20062284).
5. 5)
  - 3. Kuo, T., Lin, S., Chen, C.H.: ‘Compact ultra-wideband bandpass filters using composite microstrip – coplanar-waveguide structure’, IEEE Trans. Microw. Theory Tech., 2006, 54, (10), pp. 3772–3778 (doi: 10.1109/TMTT.2006.881624).
6. 6)
  - 8. Bates, R.N.: ‘Design of microstrip spurline band-stop filters’, IEE J. Microw. Opt. Acoust., 1977, 1, pp. 209–214 (doi: 10.1049/ij-moa.1977.0029).
7. 7)
  - 26. Ahn, D., Park, J., Kim, C., Kim, J., Qian, Y., Itoh, T.: ‘A design of the low-pass filter using a novel microtrip defected ground structure’, IEEE Tans. Microw. Theory Tech., 2001, 49, (1), pp. 86–93 (doi: 10.1109/22.899965).
8. 8)
  - H. Wang , L. Zhu . Ultra-wideband bandpass filter using back-to-back microstrip–CPW transition structure. Electron. Lett. , 24 , 1337 - 1338
9. 9)
  - A. Abbosh . Design method for ultra-wideband bandpass filter with wide stopband using parallel-coupled microstrip lines. IEEE Trans. Microw. Theory Tech. , 1 , 31 - 38
10. 10)
  - T.N. Kuo , S.C. Lin , C.H. Chen . Compact ultra-wideband bandpass filter using composite microstrip-coplanar-waveguide structure. IEEE Trans. Microw. Theory Tech. , 3772 - 3778
11. 11)
  - G.M. Yang , R.H. Jin , J.P. Geng . Planar microstrip UWB bandpass filter using U-shaped slot coupling structure. Electron. Lett. , 25 , 1461 - 1463
12. 12)
  - 1. Federal Communications Commission: ‘Revision of part 15 of the commission's rules regarding ultra-wideband transmission systems’. Technical Report, ET-Docket 98–153, FCC02–48, April 2002.
13. 13)
  - D. Ahn , J.-S. Park , C.-S. Kim , Y. Qian , T. Itoh . A design of lowpass filter using the novel microstrip defected ground structure. IEEE Trans. Microw. Theory Tech. , 1 , 86 - 93
14. 14)
  - L. Zhu , H. Wang . Ultra-wideband bandpass filter on aperture backed microstrip line. Electron. Lett. , 18 , 1015 - 1016
15. 15)
  - R.N. Bates . Design of microstrip spurline bandstop filters. IEE J. Microw. Opt. Acoust. , 6 , 209 - 214

Modelling and validation of a simple and compact wide upper stop band ultra-wideband bandpass filter

References

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