Size Reduction and Harmonic Suppression of Parallel Coupled-Line Bandpass Filters Using Defected Ground Structure
Keywords:
Size Reduction and Harmonic Suppression of Parallel Coupled-Line Bandpass Filters Using Defected Ground StructureAbstract
A novel miniaturized parallel coupledline bandpass filter with suppression of second, third and fourth harmonic frequencies, is demonstrated in this paper. The new filter is based on the slow-wave effect of the Defected Ground Structure (DGS) to achieve size minimization, while the spurious responses are eliminated by the band-rejection property of the DGS unit. These features offer the classical parallel coupled-line bandpass filter simultaneous compactness and wide stopband performance. Using the proposed DGS unit, does not require the filter parameters to be recalculated and, this way, the classical design methodology for microstrip parallel coupled-line filters can still be used. As an example, a 2.0 GHz parallel coupledline filter has been designed and measured in order to show the validity of the proposed DGS. Compared with the conventional parallel coupledline bandpass filters, the second, third and fourth measured spurious responses are suppressed to - 45, -43 and -34 dB, respectively. In addition, the size of the prototype filter is reduced by 20% compared to that of the conventional parallel coupled-line filter.
Downloads
References
B. Easter and K. A. Merza, “Parallel-
coupled-line filters for inverted-microstrip
and suspended-substrate MIC’s,” 11th
European Microwave Conference , pp. 164-
, 1981.
A. Riddle, “High performance parallel
coupled microstrip filters,” IEEE MTT-S
International Microwave Symposium
Digest, vol. 1, pp. 427-430, 1988.
S. L. March, “Phase velocity compensation
in parallel-coupled microstrip,” IEEE MTT-
S International Microwave Symposium
Digest, vol. 82, pp. 410-412, 1982.
J. Bahl, “Capacitively compensated high
performance parallel coupled microstrip
filters,” IEEE MTT-S International
Microwave Symposium Digest, vol. 2, pp.
-682, 1989.
T. Kuo, M. Jiang, and H. J. Chang, “Design
of parallel-coupled microstrip filters with
suppression of spurious resonances using
substrate suspension,” IEEE Transactions
on Microwave Theory and Techniques , vol.
, pp. 83-89, 2004.
T. Lopetegi, M. A. G. Laso, J. H. M.
Bacaicoa, D. Benito, M. J. Garde, M.
Sorolla, and M. Guglielmi, “New microstrip
“wiggly-line” filters with spurious passband
suppression,” IEEE Transactions on
Microwave Theory and Techniques, vol. 49,
pp. 1593-1598, 2001.
T. Kuo, W. H. Hsu, and W. T. Huang,
“Parallel coupled microstrip filters with
suppression of harmonic response,” IEEE
Microwave and Wireless Components
Letters, vol. 12, pp. 383-385, 2002.
B. S. Kim, J. W. Lee, and M. S. Song,
“Modified microstrip filters improving the
suppression performance of harmonic
signals,” IEEE MTT-S International
Microwave Symposium Digest, vol. 1, pp.
-542, 2003.
J. S. Park, J. S. Yun, and D. Ahn, “A design
of the novel coupled-line bandpass filter
using defected ground structure with wide
stopband performance“ IEEE Transactions
on Microwave Theory and Techniques , vol.
, no. 1, pp. 2037-2043, January 2001.
P. Cheong and K. W. Tam, “Novel folded-
end parallel-coupled-line microstrip filter
with 2nd and 3rd harmonic responses
suppression,” Mediterranean Microwave
Symp., p. 115, 2004.
J. C. Liu, B. H. Zeng, J. M. Chang, C. H.
Chien, C. C. Chang, and D. C. Chang,
“Modified maximally flat parallel-coupled
lines for band-pass filter applications and
miniaturizations,” Microwave and Optical
Technology Letters, vol. 50, pp. 902-906,
X. Q. Chen, X. W. Shi, Y. C. Guo, and M.
X. Xiao, “A novel dual band transmitter
using microstrip defected ground structure,”
Progress In Electromagnetics Research
(PIER), vol. 83, pp. 1-11, 2008.
R. Sharma, T. Chakravarty, S. Bhooshan,
and A. B. Bhattacharyya, “Design of a novel
dB microstrip backward wave coupler
using defected ground structure,” Progress
In Electromagnetics Research (PIER) , vol.
, pp. 261-273, 2006.
H. D. Oskouei, K. Fo rooraghi, and M.
Hakkak “Guided and leaky wave
characteristics of periodic defected ground
structures,” Progress In Electromagnetics
Researc (PIER), vol. 73, pp. 15-27, 2007.
J. Chen, Z. B. Weng, Y. C. Jiao, and F. S.
Zhang, “Lowpass filter design of hilbert
curve ring defected ground structure,”
Progress In Electromagnetics Research
(PIER), vol. 70, pp. 269-280, 2007.
J. S. Lim, H. S. Kim, D. Ahn, and S. Nam,
“A power amplifier with efficiency
improved using defected ground structure,”
IEEE Microwave and Wireless Components
Letters, vol. 11, pp. 170-172, 2001.
D. Ahn, J. Park, C. Kim, J. Kim, Y. Qian,
and T. Itoh, “A design of the low-pass filter
using the novel microstrip defected ground
structure,” IEEE Transactions on
Microwave Theory and Techniques , vol. 49,
pp. 86-93, 2001.
S. B. Cohn, “Parallel-coupled transmission-
line-resonator filters,” IRE Transactions on
Microwave Theory and Techniques, vol. 6,
pp. 223-231, 1958


