A coupled line type of Wilkinson power divider with flexible bandwidth and out-of-band rejection performance

Disclosed is a coupled line type power divider having rejection performance of a flexible bandwidth and an out-of-band. Proposed is a Wilkinson power divider having serial-transmission lines and coupled lines. It is possible to control a difference between even-mode/odd-mode impedances of the utilized coupled lines by employing two pairs of transmission lines. Thus, rejection performance of a bandwidth and an out-of-band can be changed at the same time. A transmission line adopted in theoretical analysis and experiments not only affects rejection performance of a bandwidth and an out-of-band, but also reduces difficulty of processing by changing the difference between even-mode/odd-mode impedances of the utilized coupled lines. Design equations were derived, and the proposed power divider (PD) shows rejection performance of a relatively high bandwidth and a relatively wide out-of-band. The power divider can be simply manufactured without via holes as well as additional lumped elements formed in the substrate. The power divider comprises: a substrate; an input unit; an impedance matching circuit; a coupled line type first transmission line and a coupled line type second transmission line; and an output unit.