Patent ID: 6342966
Filing Date: 2002-01-29
Classification: H04B

Abstract:
A bi-directional optical signal amplification device, comprising:(i) an input/output port for an optical communications signal band &Dgr;&lgr;1, and for an optical communications signal band &Dgr;&lgr;2, respectively; (ii) an input/output port for an optical communications signal band &Dgr;&lgr;2 and for an optical communications signal band &Dgr;&lgr;1, respectively; (iii) a substantially unidirectional first amplification path propagating and amplifying &Dgr;&lgr;1as an in-band communications signal, including: (a) a first waveguiding gain medium dedicated only to said first amplification path and (b) a first wavelength selective insertion loss having a selected location along said gain medium to substantially propagation of an out-of-band communications signal &Dgr;&lgr;2 along said first amplification path while substantially allowing propagation of in-band &Dgr;&lgr;1 along said amplification path; (iv) a substantially unidirectional second amplification path propagating and amplifying &Dgr;&lgr;2 as an in-band communications signal, including: (a) a second waveguiding gain medium, said second gain medium being dedicated only to said second amplification path and (b) a second wavelength selective insertion loss having a selected location along said gain medium to substantially block propagation of an out-of-band communications signal &Dgr;&lgr;1 along said second amplifying path while substantially allowing the propagation of in-band &Dgr;&lgr;2 along said amplification path; (v) first communication signals routing means substantially directing input of said in-band &Dgr;&lgr;1 communication signals to said first amplification path and amplified output said in-band &Dgr;&lgr;2 communication signals to a transmission waveguide; and (vi) second communication signals routing means substantially directing input said in-band &Dgr;&lgr;2 communication signals to said second amplification path and amplified output said in-band &Dgr;&lgr;1 communication signals to a transmission waveguide, (vii) wherein the location of the first wavelength selective insertion loss and the second wavelength selective insertion loss are respectively selected to provide a pre-insertion loss gain and a post-insertion loss gain for obtaining at least one of a target noise figure performance and a target output power performance from the device.