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Artifacts with uneven sampling of red noise
1Dipartimento di Fisica, Università di Trieste and INFN-Sezione di Trieste Via Valerio, 2-I-34127 Trieste, Italy. milotti@ts.infn.it
Summary
Uneven sampling of signals can create artifacts, especially with long-memory noise processes (power-law noises). These artifacts, though often a nuisance, can be managed or even used for information encoding.
Area of Science:
- Signal processing
- Noise analysis
- Data acquisition systems
Background:
- Standard sampling systems use fixed-frequency clocks for even time intervals.
- Uneven sampling can be unavoidable in certain scenarios.
- Artifacts from uneven sampling of deterministic signals are expected, but not for noise.
Purpose of the Study:
- To investigate artifact generation in unevenly sampled noise signals.
- To identify specific noise types susceptible to artifacts from uneven sampling.
- To explore potential applications of these artifacts.
Main Methods:
- Analysis of signal sampling techniques.
- Theoretical investigation of noise processes, specifically power-law noises (1/f^alpha).
- Examination of artifact formation under uneven sampling conditions.
Main Results:
- Uneven sampling produces artifacts in long-memory noise processes (power-law noises with alpha > 2).
- These artifacts are not observed in other noise types.
- The generated artifacts can be a nuisance or utilized for information encoding.
Conclusions:
- Uneven sampling poses a challenge for specific noise types, contrary to common assumptions.
- Understanding these artifacts is crucial for accurate signal processing.
- Potential exists to leverage these artifacts for novel data encoding strategies.
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