Improved broadband dumb-bell-shaped phase shifter using multi-section stubs

A broadband dumb-bell-shaped 45° phase shifter is presented using a new design comprised of open-circuit and short-circuit multi-section stubs. A wideband phase shifter operating over the frequency range 2-6GHz was designed and fabricated for verification purposes. It was measured to have a bandwidth of about 100 for a maximum phase deviation of ±3.2°, and maximum insertion loss of 2.1dB. © The Institution of Engineering and Technology 2008.