ram of the frequency translator of the modulator; FIG. 12 is a block diagram of the demodulator located at a receiving station; I FIG. 13 is a block diagram showing the sequence detector of the demodulator; FIGS. 14 a and b are a detailed block diagram of the phase detection system of the demodulator; FIG. 15 is a block diagram of the phase decoder of the demodulator; and FIG. 16 is a block diagra