AN IMPROVED MICROSTRIP OPEN-LOOP RESONATOR BANDPASS FILTER WITH DGSS FOR WLAN APPLICATION

作者：Guo Y C^*; Weng L H; Shi X W

来源：Journal of Electromagnetic Waves and Applications, 2009, 23(4): 463-472.

DOI：10.1163/156939309787612301

This paper presents a novel harmonic-suppressed microstrip open-loop resonator bandpass filter with the different transmission line characteristic impedance of the feed line and open-loop resonator for wireless local area network (WLAN) application. To improve the stopband rejection of the filter, the dumbbell-shape defected ground structure (DGS) are applied under the feed lines to suppress the harmonics and the equivalent parameters extraction formulations of double-dumbell-shaped DGSs are the first to proposed. The bandpass filter with center frequency of 2.44 GHz were designed and fabricated on a TLX substrate with thickness of 1 mm and dielectric constant of 2.55. Measurement results show the filter has a wide stopband characteristic with 30 dB attenuation up to 7.5 GHz and only has an -1.23 dB insertion loss while it is a little larger than the conventional one. The measured results are in good agreement with the simulated results. It can be widely used for WLAN application.

• 出版日期2009
• 单位西安电子科技大学