Robust digital watermarks for audio signals

An algorithm of embedding the digital watermarks into speech signals transmitted through analog channels of VHF radio telephony of the maritime and aeronautical mobile services has been designed. For embedding DWM it was proposed to use the vector quantization of the complex envelope of narrow-band signal. DWM robustness to the intersymbol interference, multiplicative and additive interferences is provided, respectively, by the following means: 1) formation of narrow-band channels, 2) step-size adaptation in the transmitter and receiver, and 3) distribution of DWM energy over L samples. This algorithm makes it possible to implement the automatic identification of radiotelephone transmissions without the replacement of the standard radio communication equipment and variation of the operation procedures of radio telephony.