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Generalized frequency-sum beamforming for low frequencies
Jeunghoon Lee1, Yongsung Park2, Peter Gerstoft2
1School of Mechanical Engineering, Changwon National University, Uichang-gu, Changwon 51140, South Korea.
The Journal of the Acoustical Society of America
|December 16, 2024
Summary
This study introduces generalized frequency-sum (gFS) beamforming for improved low-frequency direction-of-arrival (DOA) estimation. The method offers stable, high-resolution DOA estimation, especially with limited data and single snapshots.
Area of Science:
- Signal Processing
- Array Signal Processing
- Acoustics
Background:
- Direction-of-arrival (DOA) estimation is crucial in various applications, particularly in the low-frequency range where traditional methods face limitations.
- Achieving high spatial resolution in low-frequency DOA estimation is challenging due to the long wavelengths involved.
Purpose of the Study:
- To enhance spatial resolution for low-frequency direction-of-arrival (DOA) estimation.
- To introduce and validate a novel beamforming technique, generalized frequency-sum (gFS) beamforming.
Main Methods:
- Utilizing the Qth order frequency-sum autoproduct within the gFS beamforming framework.
- Applying constraints on the order Q based on the array's spatial Nyquist frequency.
- Employing multinomial expansion for theoretical analysis.
Main Results:
- gFS beamforming significantly improves spatial resolution in low-frequency DOA estimation.
- The method demonstrates stable performance with a single snapshot and is robust to steering vector coherence.
- Analysis confirmed the inapplicability of gFS for multi-DOA scenarios.
Conclusions:
- Generalized frequency-sum (gFS) beamforming is a practical and effective solution for single-DOA estimation in the low-frequency range.
- The technique is particularly advantageous when dealing with limited data or single snapshots.
- gFS offers a valuable alternative to existing high-resolution beamformers under specific conditions.
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