Tokyo, Japan – March 28, 2025 – Furukawa Electric Co., Ltd. (2-6-4 Otemachi, Chiyoda-ku, Tokyo; President: Hideya Moridaira) has developed an S-band Lumped Raman Amplifier Module designed to expand bandwidth for high-volume communications. This new amplifier features a gain tilt control function and has successfully amplified S-band optical signals (70nm wavelength band) with a gain of at least 30dB and gain flatness of 0.4dB or lower. The amplifier will be exhibited at OFC 2025 in the United States, with sample shipments planned for the second half of 2025.

Figure 1. External view of the S-band lumped Raman amplifier.

Background

The global demand for data traffic continues to surge due to the increased use of smartphones, cloud computing, video sharing, and generative AI. This rapid growth necessitates greater transmission capacity in medium- and long-distance optical telecommunications networks. To meet these demands, expanding the telecommunications bandwidth from the current C- and L-bands to the S- and U-bands is under consideration. However, conventional erbium-doped fiber amplifiers (EDFAs) cannot amplify light in these bands.

Development Details

Leveraging 25 years of expertise in laser manufacturing and fiber technology, Furukawa Electric has developed an S-band Lumped Raman Amplifier Module. Unlike distributed Raman amplifiers, which amplify signals using the transmission fiber, lumped Raman amplifiers incorporate an internal amplification medium, enabling high gain amplification.

The new amplifier utilizes the FRL1441U series pump laser and a dual-port Raman pump as the light source, along with a high non-linear fiber (HNLF) as the amplification medium. This combination achieves a highly efficient amplification gain of at least 30dB (High Gain Type), gain flatness of 0.4dB or lower (High Power Type), and a noise figure (NF) of 4.7dB (both types). Additionally, the gain tilt control function, adjustable by ±3dB, allows users to fine-tune system performance.

Main characteristics

The current development was conducted and achieved as part of the National Institute of Information and Communications Technology (NICT) commissioned research “Beyond 5G – Development of extended range optical node technology for realizing ultra-high speed, large volume networks” (Key Issue JPJ012368C04501) and the 2024 Function Realization and International Joint R&D Program “Innovative ICT Fund Projects for Beyond 5G/6G” (JPJ012368G60101).

Exhibition and Sample Shipments

Furukawa Electric will showcase the amplifier at OFC 2025 in San Francisco, California, from April 1-3, 2025, at the Lightera Booth No. 2843. Sample shipments are scheduled to begin in the second half of 2025.

For more information on OFC 2025 visit: https://www.ofcconference.org/en-us/home/

Technical Notes

1. S- and U-bands: These bands define optical signal frequency ranges, with the S-band having a higher frequency than the C-band and the U-band a lower frequency than the L-band.
2. Bandwidth Expansion: Expanding the telecommunications bandwidth increases data transmission capacity, enabling high-speed, large-volume communications. Utilizing new frequency bands such as the S- and U-bands will help accommodate growing data traffic demands.

Related News Releases

Development of a new pump laser for high output power, low power consumption Raman amplifiers by expanding the range of the FRL1441U Series to support the S-band and L-band
https://www.furukawa.co.jp/en/release/2023/comm_20230302-2.html

Development of a high output, low power consumption, small S-,C-,L-band dual port pump laser for Raman amplifiers
https://www.furukawa.co.jp/en/release/2023/comm_20230929.html

Improved the performance of the dual port pump laser for Raman amplifiers
https://www.furukawa.co.jp/en/release/2024/comm_20240322.html

Commitment to Sustainability

Furukawa Electric Group is committed to the United Nations Sustainable Development Goals (SDGs). Through Vision 2030, the company is working to integrate information, energy, and mobility solutions for a more sustainable world. This breakthrough in Raman amplifier technology supports our goal of reducing environmental impact and creating a greener communications infrastructure.

For more details on Furukawa Electric’s sustainability efforts, visit: https://furukawaelectric.disclosure.site/en/themes/182