Christopher Towery

Unrepeatered 100G Transmission Over 520.6 km of G.652 Fiber and 556.7 km of G.654 Fiber With Commercial Raman DWDM System and Enhanced ROPA

We report the results of 100G unrepeatered transmission aimed at achieving the longest distance without any inline active elements. The unrepeatered transmission system uses commercial distributed Raman pump modules, enhanced ROPA, and real-time processing coherent 100G transceivers (PM-QPSK) with soft-decision FEC. Two types of ultra-low loss fibers, G.652B and G.654B compliant, are fully characterized and used as span fiber. First, a single 100G channel is successfully transmitted over 520.6 km of G.652B fiber (86.2 dB) in a lab trial. Second, cabled large effective area, ultra-low loss G.654B fiber in a field environment is used as span fiber. A single 100G channel and four 100G channels are transmitted over 556.7 km (90.2 dB) and 523.2 km (84.8 dB), respectively.

Towards Superior Transmission Performance in Submarine Systems: Leveraging UltraLow Attenuation and Large Effective Area

This paper expands our previous work on record-low attenuation of 0.1460 dB/km, measured on a silica-core fiber with 148 μm2 effective area. We describe the technology used to achieve such low level of attenuation and quantify other span loss characteristics, such as maintaining ultralow attenuation after cabling and splice loss reduction using “bridge” fiber and tapering techniques. We also show that a superior transmission performance in submarine networks is achieved using a combination of ultralow attenuation and large effective area, and discuss the impact of span length on system performance. We finally demonstrate that the reduction in fiber attenuation provides an additional benefit of lower optimum power into the fiber, therefore, relaxing the maximum output power requirements of submarine EDFAs.

150 x 120 Gb/s unrepeatered transmission over 409.6 km of large effective area fiber with commercial Raman DWDM system

15 Tb/s unrepeatered transmission is achieved over 409.6 km (68.2 dB) of large effective area fiber using forward and backward distributed Raman amplification and a remotely-pumped erbium-doped optical amplifier. This result provides a record capacity-reach product of 6.14 Pb/s-km over a single fiber type. We also demonstrate channel growth from 10 to 150 waves within 61 nm amplification bandwidth.

Ultra-long unrepeatered transmission over 607 km at 100G and 632 km at 10G

This paper reports record unrepeatered transmission results using forward and backward distributed Raman amplifications, large effective area ultra-low loss fiber and enhanced ROPAs with additional pumping fibers. Coherent 100 Gb/s with PM-QPSK modulation format and OOK 10G transmission are demonstrated over 607 km (97.2 dB) and 632 km (101.0 dB), respectively.

Impact of adaptive-rate transponders and fiber attributes on the achievable capacity

We use the analytical Gaussian noise model to assess the achievable capacity over a fully transparent network with 18 nodes and 26 physical connections. By applying a network-centric approach, we show that the use of adaptive modulation in combination with ultralow loss fiber can provide an increase in the achievable capacity. The use of ultralow loss, large effective area fibers can allow for further capacity increase.

150 × 120 Gb/s unrepeatered transmission over 333.6 km and 389.6 km (with ROPA) G.652 fiber

A record capacity of 15 Tb/s unrepeatered transmission has been demonstrated over 333.6 km (55.4 dB) and 389.6 km (64.3 dB) with ROPA. All transmission results have been achieved with G.652 fiber using forward and backward distributed Raman amplification.

15 Tb/s Unrepeatered Transmission over 409.6 km using Distributed Raman Amplification and ROPA

15 Tb/s (150 × 120 Gb/s) unrepeatered transmission is achieved over 409.6 km (68.2 dB), corresponding to a record capacity-reach product of 6.14 Pb/s-km. We also demonstrate channel growth from 10 to 150 waves within 61 nm amplification bandwidth.

150 × 120 Gb/s transmission over 3,780 km of G.652 fiber using all-distributed Raman amplification

Commercial all-distributed Raman system is demonstrated to support real-time error-free transmission of 150 channels × 120 Gb/s at 50 GHz channel spacing over 3,780 km of G.652 fiber with backward Raman pumping.

43Gbit/s RZ-DQPSK transmission over 1000km of G.652 ultra-low-loss fibre with 250km amplifier spans

We demonstrate 40×43Gbit/s RZ-DQPSK transmission over 1000km of ultra-low-loss G.652 fibre with 250km amplifier spacing. Hybrid Raman-EDFA amplification with co- and contra-directional Raman pumping enables 27dB Raman gain per span and error-free post-FEC performance.