FIELD: radio engineering, communication.
SUBSTANCE: double-channel analogue door phone system comprises two cables connected between the building gateway and floor distributors, configured to transmit audio signals and/or video signals between external terminals and internal telephones; a building gateway configured to receive a call request from at least one of the external terminals, identify and designate a free cable as an internal communication channel, send a call request to each of the floor distributors over the internal communication channel and switch audio signals and/or video signals from an external terminal to the free cable; at least one of the floor distributors, configured to receive and transmit a call request to the required internal telephone, receive a response signal from the required internal telephone, if the required internal telephone is available, and switch audio signals and/or video signals from the free cable to the required internal telephone.
EFFECT: low probability of line occupancy for large buildings and residential complexes.
16 cl, 5 dwg
