Possibilities of separating two signals transmitted in the same frequency band

The theory of the optimal reception of analog messages is used to analyze the accuracy of the simultaneous estimation of two independent messages transmitted by means of two AM or phase-modulated signals in the same frequency band. The total separation of two phase-modulated signals with synchronous carrier frequencies is demonstrated for the case when the phase shift between the carriers is equal to pi/2. An analysis is presented of the dependence of energy losses occurring in the separation of two signals with nonsynchronous carrier frequencies on the mismatch between them.