Flying measurement microphone

• Applicants: Dr.-Ing. Gert Herold; Professor Dr.-Ing. Ennes Sarradj
• Subject Area: Measurement Systems ; Acoustics
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 555887713

The measurement of sound pressure levels at designated measurement locations is a very common task in the context of characterizing noise emissions and immissions. During outdoor measurements, these measurement locations are not always easily accessible with a microphone, which is why the idea of using a flying platform for the measurements, equipped with a microphone, to reach these individual measurement locations with less effort, is logical. Therefore, the aim of this project is to establish a method for measuring sound pressure levels based on a multicopter drone with microphones. This should enable easily achievable measurements at locations that would otherwise be difficult to access from the ground. The technology and signal processing required for the measurement method will be developed and implemented in a demonstration experiment. To achieve this, a multicopter drone will be used as the base, and a microphone array with the necessary signal acquisition, signal processing, and communication will be realized on it. The main challenge is to remove the noise generated by the drone's rotors from the acquired data so that only the sound to be measured is present in the measurement results. Therefore, various signal processing algorithms will be developed and implemented in the project, which can separate the drone's own noise from the sound to be measured. Indoor experiments in anechoic chamber under well-controlled acoustical environment conditions are conducted to determine the most suitable variants of signal processing and drone configurations and to obtain calibration data. Modeling of the measurement method and a systematic examination of measurement uncertainty will also be addressed in the project to provide uncertainty estimates for specific measurement situations. As a demonstration of the flying measurement microphone, the measurement of the sound power of a larger sound source in an outdoor environment is foreseen.

• DFG Programme: Research Grants