Reducing contaminating noise effects when calculating low-boom loudness levels
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View abstract on PubMed
Summary
This summary is machine-generated.NASA
Area Of Science
- Acoustics
- Aerospace Engineering
- Signal Processing
Background
- Low-boom supersonic aircraft like NASA's X-59 generate sonic booms that can be perceived differently due to noise contamination.
- Instrumentation and ambient noise can inflate sonic boom perception metrics by several decibels, affecting test accuracy.
Purpose Of The Study
- To develop and compare robust low-pass filtering techniques for removing noise contamination from low-boom recordings.
- To assess the effectiveness of these filters in improving the accuracy of sonic boom perception metrics.
Main Methods
- Development and application of a time-domain Butterworth-magnitude filter.
- Development and application of a frequency-domain Brick Wall filter.
- Comparison of filter performance against simulated and real-world noise data and a modified ISO 11204 correction.
Main Results
- Both the Butterworth and Brick Wall filters effectively reduced noise contamination in metric calculations.
- The filters demonstrated comparable performance to the modified ISO 11204 correction.
- The Butterworth filter successfully removed statistical correlation between ambient and boom levels in real-world data.
Conclusions
- Robust low-pass filtering techniques, specifically Butterworth and Brick Wall filters, can accurately calculate sonic boom metrics even with moderate noise contamination.
- These methods are beneficial for NASA's X-59 and future low-boom supersonic aircraft testing, ensuring reliable data collection.
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