Patent ID: 8897649

Claim:
An apparatus, comprising: a nonlinear optical device configured to optically mix, via a first nonlinear optical process, a first modulated optical signal and a second modulated optical signal to generate a first mixed signal and a second mixed signal; an optical detector configured to generate a first measure and a second measure, said first measure being a measure of the first mixed signal and said second measure being a measure of the second mixed signal; and a signal processor configured to: determine a constellation symbol based on the first and second measures; and decode the constellation symbol to determine a corresponding bit word carried by the first and second modulated optical signals; and wherein the first nonlinear optical process is a Bragg-scattering process; and wherein the nonlinear optical device is configured to optically mix, via the Bragg-scattering process, the first modulated optical signal, the second modulated optical signal, a first optical-pump signal, and a second optical-pump signal, with the first mixed signal and the second mixed signal being generated via said mixing.