フセイ ユウシ ニ タイスル ケイジ セキニン

末永敏和教授退職記念

フジツ ノ テイトウケン セッテイ カリトウキ ト オウリョウザイ サイケツ ヘイセイ ニジュウイチネン サンガツ ニジュウロクニチ ケイシュウ ロクジュウサンカン サンゴウ ニヒャクキュウジュウイチコウ

判例研

ハイニンザイ ニ オケル ザイサンジョウ ノ ソンガイ ヨウケン ニ ツイテ 1

論

Transmission of PM-QPSK and PS-QPSK with different fiber span lengths

We perform experimental and numerical investigations of the transmission reach of polarization-switched QPSK (PS-QPSK) and polarization-multiplexed QPSK (PM-QPSK) for three different fiber span lengths: 83, 111 and 136 km. In the experimental comparison we investigate the performance of PS-QPSK at 20 Gbaud and PM-QPSK at the same bit rate (60 Gbit/s) and at the same symbol rate, both the single channel case and a WDM system with 9 channels on a 50 GHz grid. We show that PS-QPSK gives significant benefits in transmission reach for all span lengths. Compared to PM-QPSK, use of PS-QPSK increases the reach with more than 41 % for the same symbol rate and 21 % for the same bit rate. In the numerical simulations we use the same data rates as in the experiment. The simulation results agree well with the experimental findings, but the transmission reach is longer due to the absence of various non-ideal effects and higher back-to-back sensitivity. Apart from using data coded in the absolute phase in the simulations, we also investigate differentially coded PS-QPSK for the first time and compare with PM-QPSK with differential coding. The power efficiency advantage of PS-QPSK then increases with approximately 0.3 dB at a bit error rate of 10-3, resulting in a further relative transmission reach improvement over PM-QPSK. Both the experimental and the numerical results indicate that PS-QPSK has slightly higher tolerance to inter-channel nonlinear crosstalk than PM-QPSK

サギ ザイ ニ オケル ケイヤク ジョウ ノ キリツ ニ ツイテ

論

トクシュ サギ ジアン ニ オケル コイ ト キョウボウ

論

ゴフリコミ ト ザイサンハン ヤマグチ チハン レイワ 5ネン 2ガツ 28ニチ サイバンショ web ニ ヨセテ

論

ハイニンザイ ノ トリカガイ モクテキ ニ ツイテ

論

Real-time, Software-Defined, GPU-Based Receiver Field Trial

We demonstrate stable real-time operation of a software-defined, GPU-based receiver over a metropolitan network. Massive parallelization is exploited for implementing direct-detection and coherent Kramers-Kronig detection in real time at 2 and 1 GBaud, respectively.Comment: Accepted for presentation at the European Conference on Optical Communications (ECOC) 202

Field Trial of a Flexible Real-time Software-defined GPU-based Optical Receiver

We introduce a flexible, software-defined real-time multi-modulation format receiver implemented on an off-the-shelf general-purpose graphics processing unit (GPU). The flexible receiver is able to process 2 GBaud 2-, 4-, 8-, and 16-ary pulse-amplitude modulation (PAM) signals as well as 1 GBaud 4-, 16- and 64-ary quadrature amplitude modulation (QAM) signals, with the latter detected using a Kramers-Kronig (KK) coherent receiver. Experimental performance evaluation is shown for back-to-back. In addition, by using the JGN high speed R&D network testbed, performance is evaluated after transmission over 91 km field-deployed optical fiber and reconfigurable optical add-drop multiplexers (ROADMs).Comment: Accepted for publication at Journal of Lightwave Technology, already available via JLT Early Access, see supplied DOI. This v2 version of the article is improved w.r.t. v1 after JLT peer-review. This article is a longer journal version of the conference paper: S.P. van der Heide, et al., Real-time, Software-Defined, GPU-Based Receiver Field Trial, ECOC 2020 paper We1E5, also via arXiv:2010.1433