Single-Band Balanced Coupler with Wideband Common-Mode Suppression

A novel single balanced coupler with wide-band common-mode suppression is proposed. In these double-functionality balanced-coupler architectures, double-sided parallel-strip line (DSPSL) 180°phase inverters are used to realize the broad-band common-mode rejection. For practical verification, a balanced couplers operation at 1 GHz is constructed in microstrip technology and tested.