Wideband Switchable In-Phase and Out-of-Phase Power Divider with Finite-Ground Microstrip Line

In this paper, a novel power divider is designed with broadband phase reconfigurable capability. The phase difference of the power divider can be switched between 0° and 180°, and unequal power dividing ratio is achieved simultaneously. The broadband phase switchable characteristic is obtained by using a finite-width microstrip line swap and two switches, instead of relying on tightly coupled lines on high dielectric constant substrates. To validate the proposed circuit, a power divider with a 2:1 power dividing ratio at 1 GHz is designed and fabricated. Measured results show that the circuit achieves an operating bandwidth of 108%, while the return loss is better than 10 dB and the minimum in-band isolation is better than 22 dB.