METHOD FOR TRANSMISSION OF DISCRETE SIGNALS BASED ON FREQUENCY MODULATION Russian patent published in 2021 - IPC H04B3/46 H04L27/22 

FIELD: radio engineering.

SUBSTANCE: invention relates to the field of radio engineering and is intended for use in radio engineering systems, in which noise immunity is determined by the structural secrecy of the radio signals used in them. In the proposed method, a low-frequency phase-shift keyed signal is additionally generated, which is modulated by frequency modulation with a small index to the operating frequency at which the resulting frequency-shift keyed signal is transmitted. Wherein, the duration of the element of a random binary sequence, the value of the carrier frequency and the frequency modulation index are selected in such a way that the resulting frequency-shift keyed signal and the frequency modulation signal at the operating frequency occupy the same frequency band; on the receiving side, the spreading signal is subtracted from the received combined signal, which is formed in the same way as on the transmitting side, and then the resulting frequency-shift keyed signal is further processed.

EFFECT: invention increases the structural secrecy of the spectral representation of the resulting signal being formed.

1 cl, 6 dwg