Carrier wave regenerator for four phase demodulator - controls conversion oscillator with difference between signals describing input phase

摘要

The carrier wave regerator, by a 4-phase demodulator, converts and received signal into two additional 90 deg.-sifted carriers and obtain two values, X ay Y, for the Carterisa coordinates describing the phase angle of the reseived signal. The carrier wave used for the convertstion is generated by an oscillator controlled by a voltage deviced from the received signals. The control voltage is obtained for the two values X and Y by subst acting one of the other, i.e. by modotlying the modulus of the by +1 and that of the other by -1 and then adding.