Patent ID: 7831146

Claim:
An optical communication system, comprising: one or more laser-modulators providing modulated optical signals and continuous wave optical signals over one or more wavelengths; a circulator, optical splitter or cyclic arrayed waveguide router for providing optical paths for the optical signals from the laser-modulator, one or more detectors for detecting optical signals from the circulator, optical splitter or cyclic arrayed waveguide router, one or more optical fibers or guided conduits for propagating optical signals from the circulator, optical splitter or cyclic arrayed waveguide router, and a subscriber subsystem which comprises: a circulator or an optical splitter for providing optical paths for both modulated optical signals and unmodulated continuous wave optical signals, a detector for detecting the modulated optical signals, a modulation circuit for modulating the unmodulated continuous wave optical signals into return/upstream optical signals, and a fast switching tunable wavelength shifter, wherein each return/upstream optical signal is shifted in time relative to the unmodulated continuous wave optical signal.