Phase shifter driver amplifier

Claim 1

For use in a phased array antenna for microwave energy, such antenna incorporating a matrix of antenna elements and semiconductor-diode phase shifters, a plurality of driver amplifiers selectively to actuate such phase shifters from a source of forward-bias voltage and a source of back-bias voltage, each one of such driver amplifiers comprising: a. a forward-bias output stage including a transistor, such transistor being biased normally beyond cut-off, a first electrode thereof being connected to the source of forward-bias voltage; b. a back-bias output stage including an inductor having a first and a second terminal; c. output means connecting such first terminal and a second electrode of the transistor to one electrode of the semiconductor diodes in the one of the phase shifters to be actuated; d. back-biasing circuit means connecting the second terminal of the inductor to the source of back-bias voltage, such circuit means including a current limiting resistor between such second terminal and such source and a semiconductor diode between such second terminal and the second electrode of the semiconductor diodes in the one of the phase shifters to be actuated, such semiconductor diode being poled to be conductive only during each period of time when the inductor is being discharged; and e. actuating means, responsive to a forward-biasing control signal applied to the third electrode of the transistor, for causing the transistor to conduct, thereby to apply a forwardbias voltage to the semiconductor diodes in the one of the phase shifters to be actuated and to charge the inductor.