Reconfigurable multi-channel transmitter for dense wavelength division multiplexing (DWDM) optical communications

Abstract

The invention provides a high performance reconfigurable DWDM transmitter incorporating low cost discrete optical components which can be placed in v grooves etched in a silicon optical micro-board or the like, keeping costs of manufacturing low. The lasers can be packaged in modules based on the technology of meso scale optics. The physical size of a multi channel module can be no bigger than a conventional single laser module.

What is claimed is:  
     
         1 . An optical DWDM transmitter device comprising: 
 a plurality of lasers, each laser providing an optical channel;    a plurality of active control loops locking each of the plurality of lasers to an associated frequency so as to enable an independent modulation signal to be carried on each of the optical channels; and    at least one spare laser for transmitting on any of the optical channels when the associated laser fails.    
     
     
         2 . A device as in  claim 1  wherein said lasers comprise diode lasers, gas lasers, chemical lasers, or masers.  
     
     
         3 . A device as in  claim 1 , further comprising a frequency comb including a Fabry-Perot etalon, a spacing between the optional channels being defined by the etalon.  
     
     
         4 . A device as in  claim 3 , further comprising a stable reference frequency defined by a gas absorption cell, the etalon being frequency adjusted in response to the reference frequency.  
     
     
         5 . A device as in  claim 1 , wherein the feedback loops comprise a microprocessor/controller.  
     
     
         6 . A device as in  claim 1  wherein the optical channels have frequencies separated according to fiber optic telecommunication standards.  
     
     
         7 . A device as in  claim 1 , wherein the spare laser takes over the functioning of the replaced laser, transmitting the replaced laser's frequency on a millisecond time scale so as to enable restoration of DWDM optical layer communication with little disruption to transmission of any modulated signals.