System and method for synchronizing audio-visual devices on a power line communications (PLC) network

An apparatus for synchronizing video and audio streams being communicated over a power line communications (PLC) network, comprising:

• a first streaming media device configured for connecting to a power line for the receipt of operating power;
• a power line communications circuit, within said first streaming media device, configured for communicating video and audio data over said power line operating as a PLC network, between said first streaming media device and at least a second streaming media device coupled to said power line;
• means for generating a beacon signal for communicating boundaries of a beacon frame, which is divided into time slots within a contention-free portion for isochronous transmissions and a non-contention-free portion for asynchronous transmissions, to devices coupled to the PLC network;
• and
• means for outputting a reference clock, as a multi-byte clock value, within said contention-free portion of said beacon frame for updating the system time clock, which controls timing of device output, on media devices coupled to the PLC network to maintain synchronization.

A method of synchronizing the audio-video output from devices coupled to a power line communications (PLC) network, comprising:

• generating a beacon framing signal on the PLC network;
• communicating streaming media including audio, video, or a combination of audio and video between devices coupled to said PLC network;
• reserving a portion of each beacon frame, bounded by said beacon framing signal, for use in communicating isochronous transmissions, said portion being referred to as a contention-free portion;
• reserving a time slot within said contention-free period for communicating a reference time clock;
• and
• generating a reference time clock, as a multi-byte clock value, within said reserved time slot to update the system time clock on devices coupled to the PLC network for maintaining synchronization of the streaming media being output;
• wherein said synchronization is maintained on devices coupled to the power line communications (PLC) network in response to adjusting their system time clock, which controls timing of device output, to match the reference time clock.