Design of a 1 Tb/s Superchannel Coherent Receiver

Abstract

We describe the design of a trained and pilot-aided digital coherent receiver, capable of detecting a 1 Tb/s superchannel with a single optical front-end. Algorithms for receiver training are described, which calculate the equalizer coefficients, subchannel SNRs, and centroids of the transmitted constellations. Algorithms for pilot-aided operation are then described in detail, providing pilot-aided constant modulus equalization and joint carrier-phase estimation over several coherent subchannels. We demonstrate the detection of a superchannel with net bit rate in excess of 1 Tb/s with a single coherent receiver. An <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$11\times 10$ </tex-math></inline-formula> GBd DP-64QAM Nyquist superchannel is used, with 1.32 Tb/s gross bit rate.