A method operates a signal coupling device. The signal coupling device contains at least one signal branch section which is or can be connected to a terminal-side interface of the signal coupling device using signaling. At least one signal property of a signal applied to the at least one signal branch section is determined. A signal type is determined on the basis of the at least one signal property. A time duplexing signal or a frequency duplexing signal is determined as the signal type. A signal-type-specific connection is established between the terminal-side interface and an antenna-side interface of the signal coupling device.