Power line communication method and apparatus

Apparatus, for transmitting and receiving signals over residential electrical cables, comprising:

• a processor;
• at least one switch, coupled with said processor;
• at least one analog-to-digital converter (ADC), coupled with said processor;
• at least one receiver, for receiving said signals;
• at least one digital-to-analog converter (DAC), coupled with said processor;
• and
• at least one transmitter, for transmitting said signals;
• wherein said apparatus is coupled with an electrical cable comprising at least one active wire, one neutral wire and one ground wire,
• wherein at least one of said at least one transmitter and said at least one receiver comprising a coupling circuit for coupling said apparatus to said residential electrical cables, said coupling circuit comprising:
• a first transformer, comprising:
• a first network side winding;
• a first modem side winding;
• and
• a center tap,
• each of said first network side winding and said first modem side winding respectively comprising two terminals, a first terminal of said first network side winding being coupled with said at least one active wire and a second terminal of said first network side winding being coupled with said at least one neutral wire, said center tap extending from a midpoint between said two terminals of said first network side winding;
• a second transformer, comprising:
• a second network side winding;
• and
• a second modem side winding,
• each of said second network side winding and said second modem side winding respectively comprising two terminals, a first terminal of said second network side winding being coupled with said center tap and a second terminal of said second network side winding being coupled with said at least one ground wire;
• wherein a plurality of receive wire pairs are each formed from at least two of said at least one active wire, said at least one neutral wire, said at least one ground wire and said midpoint,
• wherein a plurality of transmit wire pairs are formed from at least two of said at least one active wire, said at least one neutral wire, said at least one ground wire and said midpoint, and
• wherein said at least one switch enables said apparatus to receive said signals over a given one of said plurality of receive wire pairs and to transmit said signals over a given one of said plurality of transmit wire pairs.

System, for transmitting and receiving signals over residential electrical cables comprising at least one active wire, one neutral wire and one ground wire, said system comprising:

• at least two power line modems, each one of said at least two power line modems coupling a respective electrical device with a respective electrical socket, each said respective electrical socket being coupled with said residential electrical cables,
• each one of said at least two power line modems comprising:
• a processor;
• at least one transmitter, coupled with said processor, for transmitting said signals;
• and
• at least one receiver, coupled with said processor, for receiving said signals,
• wherein at least one of said at least one transmitter and said at least one receiver comprising a coupling circuit for coupling said one of said at least two power line modems to said residential electrical cables, said coupling circuit comprising:
• a first transformer, comprising:
• a first network side winding;
• a first modem side winding;
• and
• a center tap,
• each of said first network side winding and said first modem side winding respectively comprising two terminals, a first terminal of said first network side winding being coupled with said at least one active wire and a second terminal of said first network side winding being coupled with said at least one neutral wire, said center tap extending from a midpoint between said two terminals of said first network side winding;
• a second transformer, comprising:
• a second network side winding;
• and
• a second modem side winding,
• each of said second network side winding and said second modem side winding respectively comprising two terminals, a first terminal of said second network side winding being coupled with said center tap and a second terminal of said second network side winding being coupled with said at least one ground wire;
• wherein at least one receive wire pair is formed from at least two of said at least one active wire, said at least one neutral wire, said at least one ground wire and said midpoint,
• wherein at least one transmit wire pair is formed from at least two of said at least one active wire, said at least one neutral wire, said at least one ground wire and said midpoint, and
• wherein said processor enables said at least one receiver to be coupled with said at least one receive wire pair and said at least one transmitter to be coupled with said at least one transmit wire pair.

System, for transmitting and receiving signals over residential electrical cables comprising at least one active wire, one neutral wire and one ground wire, said system comprising:

• at least two power line modems, each one of said at least two power line modems coupling a respective electrical device with a respective electrical socket, each said respective electrical socket being coupled with said residential electrical cables,
• each one of said at least two power line modems comprising:
• a processor;
• at least one transmitter, coupled with said processor, for transmitting said signals;
• at least one receiver, coupled with said processor, for receiving said signals;
• and
• a switch, coupled with said at least one transmitter and said electrical cables;
• wherein at least one of said at least one transmitter and said at least one receiver comprising a coupling circuit for coupling said one of said at least two power line modems to said residential electrical cables, said coupling circuit comprising:
• a first transformer, comprising:
• a first network side winding;
• a first modem side winding;
• and
• a center tap,
• each of said first network side winding and said first modem side winding respectively comprising two terminals, a first terminal of said first network side winding being coupled with said at least one active wire and a second terminal of said first network side winding being coupled with said at least one neutral wire, said center tap extending from a midpoint between said two terminals of said first network side winding;
• a second transformer, comprising:
• a second network side winding;
• and
• a second modem side winding,
• each of said second network side winding and said second modem side winding respectively comprising two terminals, a first terminal of said second network side winding being coupled with said center tap and a second terminal of said second network side winding being coupled with said at least one ground wire;
• wherein at least two receive wire pairs are formed from at least three of said at least one active wire, said at least one neutral wire, said at least one ground wire and said midpoint,
• wherein at least one transmit wire pair is formed from at least two of said at least one active wire, said at least one neutral wire, said at least one ground wire and said midpoint,
• wherein said switch in a respective one of said at least two power line modems determines which one of said at least one transmit wire pair said at least one transmitter, in said respective one of said at least two power line modems, transmits said signals over,
• wherein said at least one transmitter from a first one of said at least two power line modems transmits said signals over said at least one transmit wire pair,
• wherein said at least one receiver from a second one of said at least two power line modems receives said signals over said at least two receive wire pairs as a first received signal and a second received signal, and
• wherein said processor in said second one of said at least two power line modems optimally combines said first received signal and said second received signal.