Patent ID: 7386235

Claim:
A WDM passive optical network, comprising: an optical line terminal for providing upstream and downstream wavelength channels, said optical line terminal including: at least one multiple frequency CW laser source for providing upstream and downstream wavelength channels; a first circulator for directing said downstream wavelength channels in an appropriate direction for downstream data transmission; a second circulator for directing said upstream wavelength channels in an appropriate direction for upstream data to be imparted on said upstream wavelength channels; a demultiplexer for separating and directing said downstream wavelength channels to a plurality of reflective modulators for modulating respective downstream wavelength channels to impart downstream data thereto; wherein said upstream wavelength channels and said modulated downstream wavelength channels are propagated in a downstream direction toward a respective optical network unit, and wherein distinct upstream and downstream wavelength channels are provided for each optical network unit of said WDM passive optical network; an optical feeder network including a single passive optical demultiplexer for directing each of said upstream and downstream wavelength channels to a respective intended optical network unit; and a plurality of optical network units, each of said optical network units including a receiver for receiving a respective downstream wavelength channel and a reflective modulator for modulating a respective upstream wavelength channel to impart upstream data thereto and for propagating said modulated upstream wavelength channels in an upstream direction toward a respective upstream receiver; wherein states of polarization between successively generated wavelength channels are alternated and said at least one multiple frequency CW laser source comprises a dual-output multiple frequency CW laser source and a polarization beam splitter to separate the wavelengths having different polarization states to be used for upstream and downstream wavelength channels.