Design of 180°-Switched-Line Phase Shifter with Constant Phase Shift Using CRLH TL

A 180°-switched-line phase shifter with constant phase shift using composite right/left handed transmission line (CRLH TL) is presented. To achieve relatively constant phase shift over a large bandwidth, the CRLH TL and the right-handed transmission line (RH TL) is used as the reference arm and delay arm of the switched-line phase shifter, respectively. The proposed phase shifter is designed using computer simulation and fabricated for measurement. For comparison, a traditional 180°-switched-line phase shifter is also designed and simulated. Simulation and measurement results show that, our proposed phase shifter have a constant phase shift, a high return loss and a low insertion loss across the operating frequency band.