Patents Examined by Sun Pak
  • Patent number: 6751372
    Abstract: A four-port wavelength-selective crossbar switch generates an add/drop wavelength signal from a wave division multiplexed (WDM) signal using a plurality of double-sided reflectors that selectively reflects a selected wavelength channel signal of the WDM signal through optical circulators to provide low crosstalk between the dropped and added wavelength signals. The switch also reduces the number of WDM MUX-DEMUX required to one half that compared to a traditional approach. Furthermore, the switch can be designed to be wavelength cyclic with individual free spectral ranges that can be independently set to either through or add/drop states.
    Type: Grant
    Filed: December 27, 2001
    Date of Patent: June 15, 2004
    Assignee: AT&T Corp
    Inventors: Mark D. Feuer, Nicholas J. Frigo, Cedric F. Lam