Patent ID: 9294216
Filing Date: 2016-03-22
CPC Classification: H04B,H04J,H04L

Claim Text:
1. A method of transmission of digital information having a predetermined bit-rate (B) to an optical receiver via a nonlinear optical channel using an optical signal comprising a number (N) of orthogonal subcarriers, each of which carries information at a corresponding symbol rate (S) wherein each symbol encodes a number (b) of information bits such that B =NSb, wherein a measurable received signal quality Q (N, S, b =B/NS) at the optical receiver is a function of N, S and B, the method comprising the steps of: for each one of a set of values N′ for the number of subcarriers and a corresponding set of values S′ for the symbol rate for each subcarrier, wherein N′>1 and S′=B/N′b for the predetermined bit-rate B, determining a received signal quality Q′ (N′, S′, B/N′S′) corresponding to a predetermined launch power in a nonlinear regime of the optical channel; selecting the number (N) of subcarriers, and corresponding symbol rate (S) as the ones of the sets of values (N′, S′) for which the determined received signal quality (Q′) is a maximum; generating the optical signal comprising the plurality (N) of orthogonal subcarriers having the corresponding symbol rate (S) wherein each symbol encodes the number (b) of information bits; and transmitting the optical signal to the optical receiver via the nonlinear optical channel at the predetermined launch power in the nonlinear regime of the optical channel.