Abstract: A novel dual composite right/left-handed(D-CRLH) transmission line is proposed,in which unit cell is composed with a T-shaped DGS(T-DGS) and a stub with rectangular patch.Based on the transmission characteristics of the D-CRLH unit cell analyzed using full-wave simulation,a bandstop filter is designed which has the compact size and the sharp transitions at the two edges of the stop-band due to the D-CRLH TL with T-shaped DGS.The measured data for the fabricated filter show a good agreement with those using ...