POWER LINE COMMUNICATION CIRCUIT

摘要

A power line communication circuit comprises a rectifier connected to an a.c. power line utility source. The rectifier draws power from the a.c. power source and produces a low-frequency rectified d.c. voltage signal across its positive and negative output terminals with the negative output terminal being referenced as a circuit ground. The rectified d.c. voltage signal is received by a voltage-to-current converter connected to the positive output terminal of the rectifier. The voltage-to-current converter also receives a high-frequency a.c.-shaped communication input voltage signal from an external high-frequency a.c.-shaped communication signal generator. In response to the two input voltage signals, the voltage-to-current converter generates an output current which contains a low frequency d.c. component from the rectified d.c. input voltage signal and a high frequency a.c.-shaped component from the a.c-shaped high frequency communication input voltage signal. The high frequency a.c.-shaped communication component is superimposed on the low frequency d.c. component to place communication (data) signals on the a.c. power line.