176Tb/s Nyquist PDM 16QAM signal transmission over 714km SSMF with the modified SCFDE technique

Abstract

Nyquist pulse shaping is a promising technique for high-speed optical fiber transmission. We experimentally demonstrate the generation and transmission of a 1.76Tb/s, polarization-division-multiplexing (PDM) 16 quadrature amplitude modulation (QAM) Nyquist pulse shaping super-channel over 714km standard single-mode fiber (SSMF) with Erbium-doped fiber amplifier (EDFA) only amplification. The superchannel consists of 40 subcarriers tightly spaced at 6.25GHz with a spectral efficiency of 7.06b/s/Hz. The experiment is successfully enabled with the modified single carrier frequency domain estimation and equalization (SCFDE) scheme by performing training sequence based channel estimation in frequency domain and subsequent channel equalization in time domain. After 714km transmission, the bit-error-rate (BER) of all subcarriers are lower than the forward error correction limit of 3.8 × 10(-3).