PHASE DISCRIMINATOR CIRCUIT

摘要

A phase discriminator circuit is described comprising squaring circuits (10) and (12) to convert the input signals into square waves, an adder (14), a full wave rectifier (16) and a circuit (18) for altering the mean DC value of the rectified signal. The output of the circuit (18) is positive when the inputs have the same polarity and negative when they have opposite polarity. The signal is integrated by integrator (20) the output of which is compared with a reference threshold in a level detector (22). A control circuit (24) adjusts the threshold of detector (22) to provide hysteresis. …A differentiating circuit (26) provides differential feedback from the output to the integrator (20) to improve the response time.