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A simple model for pink noise from amplitude modulations.
Masahiro Morikawa1, Akika Nakamichi2
1Department of Physics, Ochanomizu University, 2-1-1, Otsuka, Bunkyo, Tokyo, 112-8610, Japan. hiro@phys.ocha.ac.jp.
Scientific Reports
|May 24, 2023
Summary
We present a new model explaining pink noise (1/f fluctuation) using accumulating frequency waves. This mechanism, based on amplitude modulation, offers insights into phenomena like solar flares without requiring dissipation or long-term memory.
Area of Science:
- Physics
- Complex Systems
- Signal Processing
Background:
- Pink noise, or 1/f fluctuation, is a ubiquitous signal in nature.
- Existing models often involve dissipation or long-time memory, which are not universally applicable.
Purpose of the Study:
- To propose a novel, simple model for the origin of pink noise.
- To explain pink noise generation through wave accumulation and amplitude modulation.
Main Methods:
- Modeling spontaneous wave generation in systems with synchronization, resonance, and infrared divergence.
- Analyzing the beat mechanism as amplitude modulation.
- Investigating the demodulation process leading to pink noise.
Main Results:
- A simple model for pink noise generation based on accumulating frequencies is proposed.
- The beat mechanism effectively creates low frequencies from small systems via amplitude modulation.
- The generated pink noise is independent of dissipation or long-time memory.
Conclusions:
- The proposed model offers a new perspective on pink noise origins.
- This mechanism can explain pink noise in diverse fields, including geophysical and astrophysical phenomena.
- Further investigation into pink noise in earthquakes, solar flares, and stellar activities is suggested.
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