ВВЕДЕНИЕ В ТЕОРИЮ СТАТИСТИЧЕСКОЙ МОДУЛЯЦИИ

Abstract

Using new knowledge and models of known signals with amplitude shift keying (ASK), build a statistical theory of designing promising modems for information and control systems. The statistical theory is based on the characteristic function of A. Lyapunov of a random signal. It is proposed to consider the characteristic function of a non-deterministic signal with ASK, which simultaneously with the amplitude of the oscillation is modulated by a telegraph message. Taking into account this phenomenon, it was decided to further investigate the ASK signal from the standpoint of the so-called statistical shift keying (SSK), since the advantages of the new modulation method according to the forecast will significantly increase the performance of the proposed modem. The old demodulator is removed in the ASK modem and a patented demodulator is installed for receiving SSK signals using estimates of the real and imaginary parts of the Lyapunov characteristic function. The analysis of the energy performance and noise immunity of the modernized modem is made. As a result of the use of the first discovered property of the Lyapunov characteristic function, the noise immunity of a digital system with amplitude shift keying is increased by ten orders of magnitude by including a promising modem in its composition, and an energy gain of 10 dB compared to QPSK or 13 dB compared to ASK is obtained. Practical relevance: Replacing old ASK signal modems with new SSK signal modems will increase the quality of digital systems many times and make them competitive with other systems, including QPSK digital systems.