A novel design for a MMIC 180 degree phase shifter

A novel circuit topology is discussed for the design a 180 degrees phase shifter. The approach exploited the dual nature of the tee and pi configurations of the lowpass and highpass filter topologies. The resulting configuration required fewer elements than conventional switched filter approaches and did not require complementary control voltages. It has been realized by using MESFETs. When the switching elements are in the low-impedance state, the circuit becomes a highpass pi network. In the high-impedance state, the network forms a lowpass tee network. This topology requires only a single control signal halving the complexity of the switch driver. Additionally, the number of phase shifting components is reduced to only two inductors and two capacitors.<>