Patent ID: 7190904

Claim:
A method of encoding data in an optical signal including a center wavelength, the method comprising: directing the optical signal through a filter mechanism having a passband function including a center wavelength; and changing the length of the center wavelength of the optical signal to establish a difference between the lengths of the center wavelengths of the filter mechanism and the optical signal, wherein the difference between the lengths of the center wavelengths of the filter mechanism and the optical signal represents data; wherein: the represented data are analog data; and the changing step includes the steps of i) providing a look-up table having wavelength differences associated with data values, ii) obtaining from the look-up table a specified wavelength difference for a given data value, and iii) encoding the given data value in the optical signal by changing the length of the center wavelength of the optical signal to establish the specified wavelength difference between the center wavelengths of the filter mechanism and the optical signal.