Patent ID: 6144290
Filing Date: 2000-11-07
Classification: H04B

Abstract:
A device for monitoring the transmission of power line carrier currents on a low voltage electrical power distribution network, said power line carrier currents comprising a series of bursts of radio frequency signals at first and second carrier frequencies respectively representative of the true value of a logical signal in the form of frames and the complemented value of that true value, characterized in that said device includes:sensor means employing magnetic coupling to generate from said power line carrier currents a series of detected high frequency signals the carrier frequency of which is equal to the carrier frequency of the radio frequency signals;local oscillator means for generating at least one radio frequency reference frequency signal the frequency of which is in the frequency band of the detected signals;frequency changer means receiving said detected high frequency signals and said radio frequency reference frequency signal and delivering a baseband audio frequency signal;a demodulator circuit receiving said baseband audio frequency signal and delivering a detected low frequency signal representative of the envelope of the frames constituting said power line carrier currents; anda transducer circuit receiving the detected low frequency signal and generating a sound signal representative of the existence or the non-existence of power line carrier currents on the low voltage electrical power distribution network.