Patent ID: 7321730
Filing Date: 2008-01-22
Classification: H04B,H04J,H04Q

Abstract:
1. A transmitter for an optical network unit (ONU) for transmitting data over a return data channel of a passive optical network in accordance with a predefined time-sharing protocol, the transmitter comprising: a laser driver for driving a laser of the transmitter to generate an optical carrier; a modulation sub-system for modulating data onto the optical carrier generated by the laser; and a secondary modulation sub-system for impressing an ONU identifier onto the optical carrier, the ONU identifier serving to identify the ONU to a network monitor that monitors the return data channel, the secondary modulation sub-system comprising a tone source for supplying a tone that serves as the ONU identifier to a tone modulator to modulate the ONU identifier onto the optical carrier; and a switch for selectively switching the tone to the tone modulator so that the tone modulator does not impress the ONU identifier onto the optical carrier during a timeslot allocated to the ONU.