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Frontiers of Optoelectronics

ISSN 2095-2759

ISSN 2095-2767(Online)

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Front. Optoelectron.    2019, Vol. 12 Issue (1) : 15-23    https://doi.org/10.1007/s12200-018-0833-x
REVIEW ARTICLE
Spectrally efficient single carrier 400G optical signal transmission
Jianjun YU()
Shanghai Institute for Advanced Communication and Data Science, Key Laboratory for Information Science of Electromagnetic Waves (MoE), Fudan University, Shanghai 200433, China
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Abstract

In this paper, the recent progress on spectrally efficient single carrier (SC) 400G optical signal transmission was summarized. By using quadrature phase shift keying (QPSK), 16 quadrature amplitude modulation (16QAM) and 64QAM, we can realize transmission distance over 10000, 6000 and 3000 km, respectively, with large area fiber and all-Raman amplification. To improve the system performance and generate high-order QAM, advanced digital signal processing algorithms such as probabilistic shaping and look-up table pre-distortion are employed to improve the transmission performance.
Keywords coherent detection      digital signal processing      single carrier (SC)      probabilistic shaping      OFDM     
Corresponding Author(s): Jianjun YU   
Just Accepted Date: 21 September 2018   Online First Date: 11 December 2018    Issue Date: 29 April 2019
 Cite this article:   
Jianjun YU. Spectrally efficient single carrier 400G optical signal transmission[J]. Front. Optoelectron., 2019, 12(1): 15-23.
 URL:  
https://academic.hep.com.cn/foe/EN/10.1007/s12200-018-0833-x
https://academic.hep.com.cn/foe/EN/Y2019/V12/I1/15
Fig.1  Transmitter setup of (a) 128.8-Gbaud polarization-division-multiplexing quadrature-phase-shift-keying (PDM-QPSK) signals, and (b) 120-Gbaud PDM-16QAM signals generated by ETDM methods; Mod: modulator, AWG: arrayed waveguide grating, Pol: polarization, Mux: electrical multiplexer; PM-OC: polarization-maintaining optical coupler; WSS: wavelength-selective switch; EDFA: Erbium-doped fiber amplifier
Fig.2  Experimental setup for the proposed PM-256QAM SC-400G generation, and key enabling Tx and Rx DSP algorithms
Fig.3  Conceptual diagram of a two-step polarization-tracking blind equalizer, and the received constellations and LUT
Fig.4  Graphical illustration of probabilities for PS-64-QAM
Fig.5  Diagram of the PS mapping and de-mapping
Fig.6  Experimental setup. ECL: external cavity laser, OC: optical coupler, TOF: tunable optical filter, WSS: wavelength selective switch, DAC: digital to analog convertor, EA: electrical amplifier, ATT: attenuator
Fig.7  Relationship between BER and transmission distance when the channel spacing is 50 GHz. Insert: constellation with PS-5.5 and back-to-back
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