An optical network unit (ONU) comprising a media access controller (MAC) configured to support biasing a laser transmitter to compensate for temperature related wavelength drift receiving a transmission timing instruction from an optical network control node, obtaining transmission power information for the laser transmitter, estimating a burst mode time period for the laser transmitter according to the transmission timing instruction, and calculating a laser phase fine tuning compensation value for the laser transmitter according to the burst mode time period and the transmission power information, and forwarding the laser phase fine tuning compensation value toward a bias controller to support biasing a phase of the laser transmitter.