Zhen Qu is a former research intern in the Optical Network Sensing department of  NEC Laboratories America, Inc. while studying at University of Arizona.


Flex-Rate Transmission using Hybrid Probabilistic and Geometric Shaped 32QAM

A novel algorithm to design geometric shaped 32QAM to work with probabilistic shaping is proposed to approach the Shannon limit within ~0.2 dB in SNR. The experimental results show ~0.2 dB SNR advantage over 64Gbaud PAS-64QAM, and flex-rate transmission demonstrates > 500 km reach improvement over 32QAM.

Universal Hybrid Probabilistic-geometric Shaping Based on Two-dimensional Distribution Matchers

We propose universal distribution matchers applicable to any two-dimensional signal constellation. We experimentally demonstrate that the performance of 32-ary QAM, based on hybrid probabilistic-geometric shaping, is superior to probabilistically shaped 32QAM and regular 32QAM.