A novel design for a MMIC 180 degree phase shifter

A novel circuit topology for the design of a 180-degree phase shifter is discussed. The approach exploits the dual nature of the tee and pi configurations of the lowpass and highpass filter topologies. The resulting configuration requires fewer elements than conventional switched filter approaches and does not require complementary control voltages. Though it has been realized using MESFETs, the concept is equally applicable to other switching components such as PIN diodes with potentially improved loss performance.<>