An octave band GaAs analog phase shifter

A GaAs variable-gain analog phase shifter, which operates with high phase and amplitude resolution over an octave band, has been demonstrated. An all-pass approach to the phase shifter design eliminated the need for bulky hybrid couplers and allowed better than 0.5 degrees phase resolution over an octave band. The phase shifter consists of three GaAs MMIC (monolithic microwave integrated circuit) chips in a hybrid package. It exhibits greater than 10-dB gain and 100-mW output power from 400 MHz to 1400 MHz, with a phase/amplitude settling time of less than 100 ns. The authors address the design of the three MMIC chips contained in the module and the performance of the module itself.<>