Active X-Band Phased Array Modulesand their Phase Stability

Two identical MIC-transmit-receive units wlih 1 W CW output each were. forming a twin module. GaAs IMPATT diode power amplifiers and ferrite phase shifters were used. This type of components produced phase tracking of about 0.8 phase degrees/°C in CW operation, thereby setting limits for uncontrolled temperature differences in larger arrays. With 3 m us pulses, an intra-pulse phase variation of less tan 10 degrees was measured. Improvements concerning phase stability and efficiency are expected by the use of GaAs FETs and temperature compesated ferrites or replacement of ferrites by nonferrite components.