Patent ID: 7729616

Claim:
An apparatus for receiving a plurality of mutually orthogonal, spectrally phase encoded optical signals which simultaneously occupy the same optical frequency domain, in which each encoded optical signal comprises a plurality of uniformly spaced spectral lines, all of which are modulated with data associated with each user of a plurality of users, and the modulated signals are encoded by imposing predetermined relative phase shifts between spectral lines according to the code assigned to each user, comprising: a spectral phase decoder for decoding a selected encoded optical signal to produce a decoded signal that occupies a finite sampling interval while at the same time nulling the optical power of the other encoded optical signals during the sampling time; an optical time gate for temporally extracting the selected optical signal and rejecting other interfering optical signals, all of which occupy the same frequency domain; and a demodulator and detector that is operable to extract user data from the selected optical signal; wherein the spectral phase decoder separates the individual spectral components of the signal, individually shifts the phase of each of the spectral components and coherently recombines the frequency components, so that the decoder is operable to conjugate the phase code used to encode the encoded optical signal; and wherein the spectral phase decoder comprises a plurality of high-resolution, integrated optical structures each of which separates an individual spectral component, a plurality of phase shifters operable to conjugate the phase code used to encode the encoded optical signals, and a matched plurality of integrated optical structures for coherently recombining the spectral components.