Dual-band filtering out-of-phase balanced-to-single-ended power divider with enhanced bandwidth

A novel and simple dual-band out-of-phase balanced-to-single-ended (BTSE) power divider with filtering response and enhanced bandwidth is proposed in this article. The dual-band filtering response is realized by the embedded Π-type network with short-circuited stubs, leading to an enhanced operating bandwidth. The good isolation within the whole passband is implemented only using the ground resistor. The complete theoretical analysis and closed-form equations are presented based on the equivalent even- and odd-mode circuits. And then the higher-order circuit model with the improved frequency selectivity is established based on the proposed BTSE PD. For demonstration, a brand-new and simple planar BTSE power divider operating at 1 and 2.2 GHz is simulated, fabricated, and measured, which includes outstanding advantages for filtering response, return loss, insertion loss, isolation, and common-mode suppression. Finally, a good agreement between the simulated and measured results verifies the proposed design.