MONITORING OF A DIFFERENTIAL MULTICHANNEL TRANSMISSION LINK

A monitoring device and to a method for monitoring a proper operational state of a transmission link having multiple channels, each of which is configured for the differential transmission of signals, including the following steps: feeding differential signals at a first end of the transmission link to be monitored; converting the signals received at a second end of the transmission link to be monitored into difference signals, a difference signal being formed for each channel; and comparing a quality criterion which is dependent on the distribution of the values of the difference signals to a threshold value. The quality criterion depends on the variance of the logarithms of the difference signals across the channels, for example.