Development of a coherent detector without reverse operation for signals with absolute phase-shift keying at 1800.

A new formula for the gain in noise immunity of a coherent detector of a balanced-modulation signal in front of an incoherent (quadrature) detector is obtained. It is shown analytically for the first time that in a coherent signal detector with absolute phase-shift keying (PSK) (u_фм(t)) of the A.A. Pistohlkors type and similar reverse operation is unavoidable, since the oscillation of the carrier frequency u H (t) = ± u Φ M 2 (t) is provided in them, where the signs ± are equally probable and, therefore, the interference changes them. Further, u_н(t) is multiplied with the input signal u_фм(t) in the coherent detector, from which the detected pulses have reverse signs, i.e. they are received the other way. A scheme of a signal detector with an absolute PSK at 180⁰, consisting of a coherent FM signal detector with a trigger at its output, is offered. This detector can be used both as the main one and as an additional one, for example, to the A.A. Pistolkors detector, for additional interference suppression. [ABSTRACT FROM AUTHOR]