Data transmission method for telegraphy

For a telegraphy transmission method in the LF and ULF ranges, it is proposed to use an RSB modulation method with quadrature demodulation at the receiving end and to compensate for slow shifts in the phase angle of the added carrier which occur during demodulation due to frequency deviations between the transmitter and the receiver by measuring a phase shift of this type in individual bit steps and by deriving a correction value in the quadrature channels. The phase shift is measured from the imaginary part of the CCF in a matched- filter procedure with integration of the measured imaginary part.