Patent ID: 8026628

Claim:
A system comprising: a master data clock source comprising a master data clock; one or more transponders, each comprising a corresponding local data clock; and a plurality of remote power line transceivers; wherein said plurality of remote power line transceivers are connected to a common alternating current power distribution grid; wherein each of said plurality of remote power line transceivers has a location and is operable to monitor a voltage waveform of a power line prevailing at said location; whereby said system is operable to generate a local data clock from each of said local power line waveforms, said local data clock having a frequency of p/q times the frequency of said voltage waveform, where p and q are integers greater than or equal to 1; wherein said master data clock source is operable to transmit information regarding phase and frequency of said master data clock to said one or more transponders; wherein each of said one or more transponders is operable to reconstruct said master data clock from the phase and frequency information received from said master data clock source and said transponder's own local data clock and utilize the reconstructed master data clock to align data bits injected onto said transponder's location on said power line; wherein each of said remote power line transceivers is operable to receive signals said one or more transponders and measure difference in phase of the local data clock and the master clock by monitoring the signals transmitted from any one or more of the transponders; and wherein said transponders and said remote power line transceivers are each operable to inject and receive signals on the power line.