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X-ray Pulsar Signal Denoising Based on Variational Mode Decomposition.
Qiang Chen1, Yong Zhao1, Lixia Yan1
1School of Automation Science and Electrical Engineering, Beihang University (BUAA), Beijing 100191, China.
Entropy (Basel, Switzerland)
|September 28, 2021
Summary
This study introduces a variational mode decomposition (VMD) strategy to denoise X-ray pulsar signals, improving their signal-to-noise ratio (SNR) for potential interplanetary navigation control applications.
Area of Science:
- Astrophysics
- Signal Processing
- Navigation Systems
Background:
- X-ray pulsars serve as precise natural clocks with potential for interplanetary navigation.
- Cosmic background noise significantly reduces the signal-to-noise ratio (SNR) of observed pulsar signals, hindering practical applications.
- Existing denoising methods may not effectively address the complex noise present in pulsar data.
Purpose of the Study:
- To develop and validate a novel pulsar denoising strategy using Variational Mode Decomposition (VMD).
- To enhance the signal-to-noise ratio (SNR) of X-ray pulsar signals for improved usability.
- To lay the groundwork for future interplanetary navigation control systems utilizing denoised pulsar data.
Main Methods:
- The proposed method employs Variational Mode Decomposition (VMD) to decompose pulsar signals into intrinsic mode functions (IMFs).
- Noise attenuation is achieved through the filtering effect during signal decomposition and reconstruction within the VMD framework.
- The strategy was validated using both simulated pulsar signals and archival data from the HEASARC.
Main Results:
- The VMD-based strategy effectively decomposes pulsar signals, isolating noise components.
- Significant attenuation of Gaussian noise was observed during the signal reconstruction process.
- Experimental results demonstrated the effectiveness of the VMD approach in enhancing pulsar signal quality.
Conclusions:
- The developed VMD strategy offers a promising solution for denoising X-ray pulsar signals.
- This denoising technique can improve the reliability of pulsar-based navigation systems.
- The research represents a crucial first step towards practical interplanetary navigation control using pulsars.
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