| 摘要 |
FIELD: information technology. ^ SUBSTANCE: messages can be commands for controlling guarded vehicles or other objects, as well as telemetric data. In the disclosed method, an ancillary sinusoidal signal is generated at the transmitting side with frequency inside the range of modulating frequencies used by a voice communication transmitter. The ancillary sinusoidal signal is pre-modulated with successive message signals which are generated using a frequency band which is significantly narrower than that of modulating frequencies of the voice communication transmitter. A signal at the carrier frequency of the voice communication transmitter is modulated with the obtained pre-modulated signal during transmission. At the receiving side, reception is carried out at a frequency associated with linear transformation of the carrier frequency of the voice communication transmitter and frequency of the ancillary sinusoidal signal. The received signal is filtered in a frequency band defined by the frequency band of the ancillary sinusoidal signal based on pre-modulation thereof with successive message signals. The received signal is demodulated according to the selected modulation of the ancillary sinusoidal signal. ^ EFFECT: considerably longer communication range when sending messages. ^ 6 cl, 2 dwg |
