Optical orthogonal frequency division multiplexed communications with nonlinearity compensation

A system for a data transmission via an optical communication link, comprising:

• a digital data stream entering an orthogonal frequency division multiplexed (OFDM) encoder, the encoder outputting I and Q analog signals driving an optical modulator, the modulator modulating separately each OFDM subcarrier of each channel of an initial optical beam from a light source, the modulator outputting a modulated optical beam to be transmitted in the optical link, wherein the OFDM encoder performs a compensation of the optical link transmission distortions by multiplying each subcarrier on a compensation coefficient;
• the modulated beam being received by an optical receiver, comprising:
• at least a first coherent receiver for receiving the data modulated beam and a local oscillator beam;
• a set of photodetectors receiving output beams from the optical hybrid and producing electrical signals I and Q;
• a digital signal processing unit receiving the electrical signals I an d Q, converting them into digital signals,
• an expected distortion phase shift for the i-th sampling interval, performing a distortion compensation by multiplying the signals I(ti) and Q(ti) on a coefficient depending on the expected distortion phase shift,
• transforming the digital signals into frequency domain, forming a set of spectral signals each having its own digital frequency, demodulating the data encoded in each spectral signal, and outputting a received information.