The research results of optimal coherent reception of multiposition signals in modern mobile networks are presented. The implementation of algorithms and devices provides the maximum possible noise immunity when all possible variants of the transmitted signal at the input of the demodulator are known a priori with high accuracy of the information parameter. By reducing a priori information about the received signal, it is possible to synthesize other methods of reception that are optimal under the appropriate conditions. The coherent processing algorithms of multiposition amplitude-phase modulation and amplitude-phase-difference modulation signals that are convenient for multichannel (multifrequency) systems with orthogonal channel signals are considered. In multichannel systems, for the distribution of orthogonal signals, the procedure for calculating the projections of the received signal on two mutually orthogonal oscillations with an arbitrary initial phase is used. The proposed algorithms for coherent signal processing do not require adjustment of the phase of the reference oscillations of channel signals and enable to implement both the orthogonal distribution of signals and their coherent reception.
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