Novel dual-band microwave components using composite right / left-handed transmission lines

A novel dual-band band-pass filter and a novel dual-band 1:3 series power divider are presented here, both the elements utilize the concept of composite right/left handed transmission lines (CRLH-TLs). The filter operates at 1.5GHz and 2.3 GHz, with fractional bandwidths of W₁ =10.2% and W₂ =13.0%, respectively. The divider is designed to operate at 1.14 GHz and 2.47 GHz, over the two frequency bands, it provides almost equal power splits to three output ports. Two pairs of isolation resistors are added at the output ports which are calculated from the equivalent network model of the divider. They greatly improve the isolation performance of the output ports, and that is of great use in power combination. More over, both the devices maintain a compact profile.