Development of the sensitivity calibration method for infrasound measurement devices used in volcanic activity observations

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K04101
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 21030:Measurement engineering-related
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: Yamada Keisuke 国立研究開発法人産業技術総合研究所, 計量標準総合センター, 主任研究員 (90613993)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 計測 / 校正 / 音響 / 超低周波音 / 火山 / 防災 / マイクロホン

Outline of Final Research Achievements

This study developed a calibration method for microphone sensitivity from 0.1 Hz to 1 Hz, which had not been previously established, with the aim of contributing to disaster prevention technology through infrasound monitoring. We developed a calibration system using a liquid-column type sound pressure generator as a microphone sensitivity calibration method specialized for the infrasound frequency range, enabling reliable calibration with traceability and an uncertainty of 0.2 dB. The results of this study allow for accurate comparison and integration of infrasound observation data from multiple locations, which is expected to accelerate the practical application of disaster prevention systems utilizing infrasound monitoring.

Free Research Field

音響工学

Academic Significance and Societal Importance of the Research Achievements

超低周波音は遠方まで届くため、火山噴火など大規模自然災害の観測に利用して防災に役立てる研究が進んでいる。しかし観測に使用する計測器の校正方法が確立していないことが課題であった。本研究の成果により超低周波数領域におけるマイクロホンの感度が校正可能になることで、複数点での観測結果の正しい比較・統合が可能となり、超低周波音モニタリングによる防災システムの実用化の加速が期待できる。