Wideband unbalanced fed 180-degree phase shifter using phase inverter

In this paper, the design of unbalanced fed 180° phase shifter with a wideband performances is proposed. This phase shifter uses a single dielectric substrate, and consists of multi-section Wilkinson divider, reference line, and phase inverter containing balanced-unbalanced transition in the input and output port. The simulated and measured results show that this device provides 180° phase shift with low insertion loss in the frequency band from 1 to 10 GHz.