DOI: 10.22184/2070-8963.2024.123.7.60.65

The choice of modulation type for radio systems intended for operation in absence of strict limitations to the occupied frequency range is considered. For such systems the use of multi-position frequency shift keying (M-FSK), which has high energy efficiency and low value of the radiated signal peak factor is proposed. An analysis of the fundamental features of M-FSK manipulation, which has high energy efficiency, is presented. The results of modelling of transmission channel noise immunity for different values of modulation index and multiplicity, as well as the corresponding spectral characteristics are presented. Recommendations on improving of systems with M-FSK are developed.