Study on high-linearity optical modulator for next-generation analog radio-over-fiber systems

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K14745
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 21020:Communication and network engineering-related
• Research Institution: National Institute of Information and Communications Technology
• Principal Investigator: Yamaguchi Yuya 国立研究開発法人情報通信研究機構, ネットワーク研究所フォトニックICT研究センター, 研究員 (30754791)
• Project Period (FY): 2020-04-01 – 2022-03-31
• Keywords: 光エレクトロニクス / 光変調器 / 光ファイバ無線 / 光ファイバ通信

Outline of Final Research Achievements

We conducted research and development on optical modulation devices for the advancement of analog radio-over-fiber technology. For the high-linearity LN optical modulator that we have proposed, we have achieved a basic performance improvement of more than twice by using a thin film substrate structure. We also developed a 4-level digital intensity modulator as an extension of the linear modulation technology. We demonstrated the operation of analog waveform shaping in optical domain performed at the same time as optical modulation. As an initiative for Beyond 5G, we worked on the development of an optical modulator that works with high efficiency in the millimeter-wave band, and achieved a high sensitivity of 6 dB or more compared to the conventional one with a thin film LN structure. As a demonstration of Beyond 5G link, radio-over-fiber signal transmission exceeding 70 Gbps was achieved at a carrier frequency of 100 GHz by using the newly developed device.

Free Research Field

光ファイバ通信

Academic Significance and Societal Importance of the Research Achievements

Beyond 5Gや6Gに代表される次世代無線通信や、それを支えるネットワークである次世代光ファイバ通信はICT社会を進化させていくために重要な社会インフラである。本研究では、このような新しいネットワークのための物理層における研究開発として、これまでに使うことが難しかった高周波数帯で高効率且つ高線形に動作する光変調器の新規開発に取り組み、将来ネットワークへの適用可能性を示した。