Feasibility study of SOA-preamplified coherent reception for 112 Gb/s DP-QPSK unamplified link. - Mads L. Nielsen; Lutz Molle; Thomas Richter 004; Colja Schubert (OFC/NFOEC, 2013)

Narrow guard-band distributed Nyquist-WDM using fiber frequency conversion. - Thomas Richter 004; Robert Elschner; Carsten Schmidt-Langhorst; Tomoyuki Kato; Shigeki Watanabe; Colja Schubert (OFC/NFOEC, 2013)

Characterization of polarization insensitive FOPA using a polarization-maintaining highly non-linear fiber. - Isaac Sackey; Thomas Richter 004; Christian Meuer; Robert Elschner; Mahmoud Jazayerifar; Klaus Petermann; Colja Schubert (OFC/NFOEC, 2013)

Tolerances for add/drop operation of a coherent multiplexing node based on fiber frequency conversion. - Thomas Richter 004; Carsten Schmidt-Langhorst; Robert Elschner; Tomoyuki Kato; Takahito Tanimura; Shigeki Watanabe; Colja Schubert (ECOC, 2014)

Kerr nonlinearity compensation in a 5×28-GBd PDM 16-QAM WDM system using fiber-based optical phase conjugation. - Francesco Da Ros; Isaac Sackey; Robert Elschner; Thomas Richter 004; Christian Meuer; M. Nolle; Mahmoud Jazayerifar; Klaus Petermann; Christophe Peucheret; Colja Schubert (ECOC, 2014)

Design and performance evaluation of an OPC device using a dual-pump polarization-independent FOPA. - Isaac Sackey; Francesco Da Ros; Thomas Richter 004; Robert Elschner; Mahmoud Jazayerifar; Christian Meuer; Christophe Peucheret; Klaus Petermann; Colja Schubert (ECOC, 2014)

Coherent in-line substitution of OFDM subcarriers using fiber-frequency conversion and free-running lasers. - Thomas Richter 004; Carsten Schmidt-Langhorst; Robert Elschner; Tomoyuki Kato; Takahito Tanimura; Shigeki Watanabe; Colja Schubert (OFC, 2014)

Distributed generation of a 400-Gb/s Nyquist 16QAM dense superchannel by fiber-frequency conversion. - Thomas Richter 004; Carsten Schmidt-Langhorst; Robert Elschner; Tomoyuki Kato; Shigeki Watanabe; Colja Schubert (OFC, 2014)

Characterization of a fiber-optical parametric amplifier in a 5 × 28-GBd 16-QAM DWDM system. - Isaac Sackey; Robert Elschner; Markus Nölle; Thomas Richter 004; Lutz Molle; Christian Meuer; Mahmoud Jazayerifar; Stefan Warm; Klaus Petermann; Colja Schubert (OFC, 2014)

Coherent reception and 126 GHz bandwidth digital signal processing of CO-OFDM superchannel generated by fiber frequency conversion. - Takahito Tanimura; Tomoyuki Kato; Ryo Okabe; Shoichiro Oda; Thomas Richter 004; Robert Elschner; Carsten Schmidt-Langhorst; Colja Schubert; Jens C. Rasmussen; Shigeki Watanabe (OFC, 2014)

Spatially distributed aggregation of a polarization-division multiplexed superchannel by frequency conversion in fiber. - Thomas Richter 004; Robert Elschner; Carsten Schmidt-Langhorst; Tomoyuki Kato; Takahito Tanimura; Shigeki Watanabe; Colja Schubert (ECOC, 2015)

Distributed 1-Tb/s all-optical aggregation capacity in 125-GHz optical bandwidth by frequency conversion in fiber. - Thomas Richter 004; Carsten Schmidt-Langhorst; Robert Elschner; Lutz Molle; Saleem Alreesh; Tomoyuki Kato; Takahito Tanimura; Shigeki Watanabe; Johannes Karl Fischer; Colja Schubert (ECOC, 2015)

Non-reciprocal gain due to counter-propagating pumps in a polarization-independent FOPA with diversity loop. - Isaac Sackey; Mahmoud Jazayerifar; Robert Elschner; Thomas Richter 004; Christian Meuer; Klaus Petermann; Colja Schubert (ECOC, 2015)

Broadband coherent-optical add/drop multiplexing over 400-GHz bandwidth by fiber frequency conversion. - Tomoyuki Kato; Takahito Tanimura; Thomas Richter 004; Carsten Schmidt-Langhorst; Robert Elschner; Colja Schubert; Shigeki Watanabe (OFC, 2015)

Generation of ultra-dense superchannels using frequency conversion in optical fibers. - Thomas Richter 004; Carsten Schmidt-Langhorst; Robert Elschner; Tomoyuki Kato; Takahito Tanimura; Shigeki Watanabe; Colja Schubert (OFC, 2015)

Versatile coherent in-line 4-, 16-, 32-QAM subcarrier add/drop-multiplexing by optical frequency conversion. - Carsten Schmidt-Langhorst; Thomas Richter 004; Robert Elschner; Tomoyuki Kato; Takahito Tanimura; Shigeki Watanabe; Colja Schubert (OFC, 2015)

In-line optical signal multiplexing by polarization-insensitive fiber frequency conversion. - Tomoyuki Kato; Takahito Tanimura; Takeshi Hoshida; Thomas Richter 004; Robert Elschner; Carsten Schmidt-Langhorst; Colja Schubert; Shigeki Watanabe (OFC, 2016)

Continuously tunable optical frequency shift of 1.6-Tb/s superchannel up to THz-range by polarization switched frequency conversion. - Tomoyuki Kato; Shigeki Watanabe; Takahito Tanimura; Thomas Richter 004; Robert Elschner; Carsten Schmidt-Langhorst; Colja Schubert; Takeshi Hoshida (OFC, 2017)

OSNR Measurement Comparison in Systems with ROADM Filtering for Flexible Grid Networks. - Jie Pan; Thomas Richter 004; Sorin Tibuleac (OFC, 2018)

Comparison of WDM Bandwidth Loading Using Individual Transponders, Shaped, and Flat ASE Noise. - Thomas Richter 004; Jie Pan; Sorin Tibuleac (OFC, 2018)

Identification of Soft Failures in Optical Links using Low Complexity Anomaly Detection. - Siddharth Varughese; Daniel Lippiatt; Thomas Richter 004; Sorin Tibuleac; Stephen E. Ralph (OFC, 2019)

Joint Linear and Nonlinear Noise Estimation of Optical Links by Exploiting Carrier Phase Recovery. - Daniel Lippiatt; Siddharth Varughese; Thomas Richter 004; Sorin Tibuleac; Stephen E. Ralph (OFC, 2020)

Low Complexity Soft Failure Detection and Identification in Optical Links using Adaptive Filter Coefficients. - Siddharth Varughese; Daniel Lippiatt; Thomas Richter 004; Sorin Tibuleac; Stephen E. Ralph (OFC, 2020)

Quasi-Continuous Symbol Rate Tunability for Maximum Capacity in Links Constrained by ROADM Filtering. - Steven Searcy; Thomas Richter 004; Sergey Burtsev; Sorin Tibuleac (ECOC, 2021)

Optical Performance Monitoring for Commercial Transceivers using Constellations: Practical Considerations. - Daniel Lippiatt; Hyung Joon Cho; Alex Kaylor; Varghese A. Thomas; Steven Searcy; Thomas Richter 004; Sorin Tibuleac; Stephen E. Ralph (OFC, 2022)

Experimental Study of Bandwidth Loading with Modulated Signals vs. ASE Noise in 400ZR Single-Span Transmission. - Steven Searcy; Thomas Richter 004; Sorin Tibuleac (OFC, 2022)

Benefits of quasi-continuous symbol rate tunability in links constrained by ROADM filtering. - Steven Searcy; Thomas Richter 004; Sergey Burtsev; Sorin Tibuleac (JOCN, 2022)

1 Tb/s and 800 Gb/s real-time transmission at 138 GBd over a deployed ROADM network with live traffic. - Thomas Richter 004; Steven Searcy; Philippe Jennevé; Dimitrios Giannakopoulos; Bill Owens; Miquel A. Mestre; Ahmed Awadalla; Sorin Tibuleac (OFC, 2023)