METHOD AND APPARATUS FOR THE TRANSMISSION OF BINARY DATA SIGNALS BY FREQUENCY SHIFT KEYING

摘要

A method for transmitting binary data signals by frequency shift keying (FSK), in which a binary data signal 1 is represented by a first frequency (f1) and a binary data signal 0 is represented by a second frequency (f2) includes addressing a first addressing input of a programmable memory with the binary data signals, in which half the periods of the two frequencies (f1, f2) are marked in two memory regions (I, II) of the programmable memory addressed by the first addressing input; controlling other address inputs with a free-running counter; and generating a pulse resetting the counter and controlling a 1:2 frequency divider having an output delivering one of the frequencies (f1, f2), when addressing a storage cell in which one of the halfperiods is marked and a modulator for carrying out the method.