Balanced-to-Unbalanced In-Phase Power Divider

This paper proposes an in-phase balanced-to-unbalanced (BTU) power divider (PD). The proposed PD is of Gysel type, so it can be realized for high power applications as well. Design equations for the proposed PD are derived analytically. Four short circuited parallel coupled lines with floating conductor are used to make circuit compact. To verify the design equations, one prototype for power division ratio 1:2 and one prototype for equal power division at a design frequency 2 GHz are fabricated and tested. Differential return loss of balanced port of both PDs is greater than 15 dB. Return loss of unbalanced ports and isolation between unbalanced ports of both PDs are greater than 15 dB. Common mode suppression is greater than 20 dB. Both PDs show good in-phase characteristic.