Novel Simplified Dual-Composite Right/Left-Handed Transmission Line and Its Application in Bandpass Filter with Dual Notch Bands
In this article, a novel simplified dual-composite right/left-handed transmission line (S-DCRLH-TL) is proposed according to the theory of dual-composite right/left-handed transmission line. The electromagnetic characteristics of S-D-CRLH-TL are analyzed by simulator, and the results indicate that the proposed structure has two narrow stopbands; they can be controlled by changing the geometry parameters of the structure. Then, a bandpass filter with dual notched bands is designed by using the unit cell of S-D-CRLH-TL, and the designed filter is simulated, fabricated and measured, the measured and simulated results are in good agreement with each other, showing that the two notched bands centered at 3.60 GHz and 5.50 GHz, and the bandwidths are 9.7% and 7.3%. This designed filter can avoid the interference to UWB communication system effectively, which comes from the signals of WiMAX and WLAN. Besides, in comparison with the other bandpass filter with notched bands, the designed filter has good electromagnetic performances.