Patent ID: 9672730
Date: 2017-06-06
CPC Classifications: G08C,H04B

Claim:
1. An apparatus for diagnosis of a communication channel, wherein a communication signal serves for data transmission via the communication channel, and wherein the communication signal is a frequency-modulated signal, the apparatus including: a receiving circuit, which serves for receiving the frequency-modulated communication signal, said receiving circuit includes a monitoring unit, which serves for determining a signal parameter of the frequency-modulated signal, a demodulator, which serves to demodulate the frequency-modulated signal, a signal processing unit, which is connected with said demodulator and with said monitoring unit, and a measuring resistor which serves for tapping the communication signal, wherein: said signal processing unit serves, at least at times, for evaluating the signal parameter of the frequency-modulated signal determined by means of said monitoring unit; the apparatus is operable alternately in modulation operation and demodulation operation, said demodulator is turned off in modulation operation, respectively no signals coming from said demodulator are processed by said signal processing unit, however, said monitoring unit in modulation operation determines a signal parameter of the communication signal, which is evaluated by said signal processing unit; and the signal parameter of the frequency-modulated, communication signal determined during the modulation operation serves to determine a value of the measuring resistor.