Signal processing method for decoding telegraphy signals and arrangement to carry out the method

摘要

Signal processing method for decoding telegraphy signals and arrangement to carry out the method. To reduce the distortions occurring in the decoding of AC telegraphy signals lying in particular in the short-wave range and transmitted at high telegraphy speed, the corresponding analog AF output signal (NF) of a telegraphy receiver is converted by means of a mixing device (1) into a higher-frequency intermediate frequency signal whose intermediate frequency fZF serves as a reference frequency of a follow-up synchronisation device (2) and a binary-digital signal corresponding to the decoded telegraphy signal is derived according to the occurring control parameter of the follow-up oscillator from the difference between the intermediate frequency fZF and the follow-up oscillator frequency of the follow-up synchronisation device (Fig. 2). <IMAGE>