Synchronization for subcarrier communication

An apparatus comprising:

• a receiver comprising:
• a local oscillator laser providing a local oscillator signal,
• a detector circuit operable to receive a first optical signal and detect a first portion of a first data stream carried by the first optical signal based on the local oscillator signal,
• a reference clock circuit supplying a clock signal,
• a first digital signal processor (DSP) operable to receive the first portion of the first data stream and supply a control signal to the reference clock circuit based on the first portion of the first data stream, the reference clock circuit being operable to adjust the clock signal based on the control signal;
• and
• a transmitter comprising:
• a second DSP;
• and
• a modulator supplying a second optical signal based on an output of the second DSP, such that the clock signal is supplied to the first and second DSPs, wherein the first DSP processes a second portion of the first data stream based on the clock signal and the second DSP supplies the output based on the clock signal.

A system, comprising:

• an optical system operable to transmit optical signals at a first data rate;
• one or more leaf systems;
• an intermediary system;
• the intermediary system operable to receive the optical signals and broadcast the optical signals to each of the one or more leaf systems;
• and
• wherein each of the one or more leaf systems comprises:
• a receiver comprising:
• a local oscillator laser providing a local oscillator signal,
• a detector circuit operable to receive a first optical signal and detect first data carried by the first optical signal based on the local oscillator signal,
• a reference clock circuit supplying a clock signal,
• a digital signal processor (DSP) operable to receive the first data and supply a control signal to the reference clock circuit based on the first data, the reference clock circuit being operable to adjust the clock signal based on the control signal;
• and
• a transmitter operable to output a second optical signal carrying second data, the second data having a second data rate that is based on the clock signal.