Compact wideband phase shifter
A compact phase shifter is presented for wideband applications consisting of circular patches located at close proximity to each other which are coupled with interconnected ground-plane circular slots located beneath the circular patches. In the proposed technique the slot-line length and radius of patch determines the magnitude of phase shift.  2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013.
phase shifter coupling circuits ultra-wideband