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Title: Joint Probabilistic-Nyquist Pulse Shaping for LDPC-coded 8-PAM Signal in DWDM Data Center Communications
M-ary pulse-amplitude modulation (PAM) meets the requirements of data center communication because of its simplicity, but coarse entropy granularity cannot meet the dynamic bandwidth demands, and there is a large capacity gap between uniform formats and the Shannon limit. The dense wavelength division multiplexing (DWDM) system is widely used to increase the channel capacity, but low spectral efficiency of the intensity modulation/direct detection (IM/DD) solution restricts the throughput of the modern DWDM data center networks. Probabilistic shaping distribution is a good candidate to offer us a fine entropy granularity and efficiently reduce the gap to the Shannon limit, and Nyquist pulse shaping is widely used to increase the spectral efficiency. We aim toward the joint usage of probabilistic shaping and Nyquist pulse shaping with low-density parity-check (LDPC) coding to improve the bit error rate (BER) performance of 8-PAM signal transmission. We optimized the code rate of the LDPC code and compared different Nyquist pulse shaping parameters using simulations and experiments. We achieved a 0.43 dB gain using Nyquist pulse shaping, and a 1.1 dB gain using probabilistic shaping, while the joint use of probabilistic shaping and Nyquist pulse shaping achieved a 1.27 dB gain, which offers an excellent improvement without upgrading the transceivers.  more » « less
Award ID(s):
1907918
PAR ID:
10158884
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Applied sciences
Volume:
9
Issue:
23
ISSN:
2076-3417
Page Range / eLocation ID:
4996-1-4996-9
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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