About Cycle Stationary of APSK-N-Signals Observed on the Output of Communication Channel with Intersymbol Interference

An algorithm for determining the conditions under which the multi-position amplitude-phase manipulated signal at the output of the communication channel becomes a cyclo-stationary process is presented. The results of its use were used to estimate the resolution times and effective memory for various types of amplitude-frequency responses of the channel presented in this paper. New properties were revealed for channels with ISI.