Title :
Transmission of 200 G PDM-CSRZ-QPSK and PDM-16 QAM With a SE of 4 b/s/Hz
Author :
Jianjun Yu ; Ze Dong ; Hung-Chang Chien ; Zhensheng Jia ; Xinying Li ; Di Huo ; Gunkel, Matthias ; Wagner, Paul ; Mayer, Horst ; Schippel, A.
Author_Institution :
ZTE Corp., Beijing, China
Abstract :
We have realized the first field transmission of 8 × 216.8-Gb/s Nyquist wavelength-division-multiplexing (N-WDM) signals over 1750-km G.652 fiber consisting of 950-km real and 800-km lab fibers with erbium-doped fiber amplifier (EDFA)-only amplification. The average loss per span is 21.6 dB. Each channel is modulated with 54.2-Gbaud (216.8-Gb/s) polarization-division-multiplexing carrier-suppressed return-to-zero quadrature-phase-shift-keying (PDM-CSRZ-QPSK) data on a 50-GHz grid giving a record spectral efficiency (SE) of 4 b/s/Hz. Digital post filtering and 1-bit maximum likelihood sequence estimation (MLSE) are introduced into the offline digital signal processing (DSP) at the receiver to suppress noise, linear crosstalk and filtering effects. We have also investigated the co-transmission of 200 G PDM-CSRZ-QPSK and 200 G PDM 16-ary quadrature-amplitude-modulation (PDM-16 QAM) signals on a 50-GHz grid, and found that PDM-CSRZ-QPSK signals have better bit-error-rate (BER) performance for both back-to-back and 700-km transmission cases. Meanwhile, PDM-16 QAM signals are subject to larger crosstalk from the neighboring Nyquist QPSK channels.
Keywords :
amplification; digital signal processing chips; erbium; error statistics; filtering theory; interference suppression; maximum likelihood sequence estimation; optical crosstalk; optical fibre amplifiers; optical fibre polarisation; quadrature amplitude modulation; quadrature phase shift keying; radio receivers; spectral analysis; wavelength division multiplexing; CSRZ; EDFA; G.652 fiber; MLSE; N-WDM signal; Nyquist QPSK channel; Nyquist wavelength division multiplexing; PDM; QAM; QPSK; SE; amplification; bit error rate; bit rate 216.8 Gbit/s; carrier suppressed return to zero; digital post filtering; digital signal processing; distance 1750 km; distance 800 km; distance 950 km; erbium doped fiber amplifier; filtering effect; frequency 50 GHz; linear crosstalk; loss 21.6 dB; maximum likelihood sequence estimation; noise suppression; polarization division multiplexing; quadrature amplitude modulation; quadrature phase shift keying; receiver; spectral efficiency; Bit error rate; Finite impulse response filter; Optical fiber amplifiers; Optical filters; Optical noise; Carrier-suppressed modulation; Nyquist wavelength- division-multiplexing transmission; coherent detection; digital signal processing; field trial; optical filter; post filter; spectral efficiency;
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2012.2212420
