Digital Coherent Modem with Space-Time Transmission and Reception of Optimal Finite Signals

The report presents a new solution to the problem of increasing the energy efficiency of a digital transmission system with multi-frequency modulation and optimal finite signals that do not cause cross-symbol interference at the outputs of narrowband filters in various modem channels. A new method for multi-frequency data transmission based on the space-time transmission and reception of optimal finite signals observed in demodulators of the digital transmission system has been proposed. New data of the spectral-energy efficiency of the developed modem are presented. From a comparative analysis with standard modems, it follows that the modem developed is superior in efficiency to the known modems.