Broadband Phase Shifter Using Loaded Transmission Line

Dept. of Electron. Eng., City Univ. of Hong Kong, Kowloon, China
IEEE Microwave and Wireless Components Letters (Impact Factor: 1.7). 10/2010; 20(9):498 - 500. DOI: 10.1109/LMWC.2010.2050868
Source: IEEE Xplore


This letter presents a novel loaded transmission line, which has a constant phase shift over a wide bandwidth, referenced to a uniform transmission line. Compared with the conventional coupled line phase shifter, the configuration shows good performance with simplicity in both design and fabrication. The optimal design parameters for different phase shift values up to 120° are also presented to allow for a quick design process. To verify the configuration, a 90° phase shifter using a T shaped open stub loaded transmission line is designed, fabricated and measured. Excellent performance is achieved with small insertion loss and phase deviation over a bandwidth of 82%.

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    • ". According to Figure 4, analogous to the phase shifter is reported in [14], it is also found that this phase shifter maintains the wide-band operation capability in a wide range of phase-shifting values. "
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