Noise and filtering
Noise and filtering is part of the Nanopore Wiki learning path. Noise and filtering determine whether nanopore events can be resolved and whether extracted features remain faithful to the original signal.
Core concepts
- Thermal, shot, capacitive, surface, and low-frequency noise can all affect nanopore recordings.
- Low-pass filtering reduces high-frequency noise but broadens rapid events.
- Sampling rate should be chosen relative to bandwidth and expected event duration.
- Noise should be reported with the same acquisition settings used for analysis.
Quality workflow
| Step | Description |
|---|---|
| 1 | Record blank baseline before sample addition. |
| 2 | Estimate baseline mean, drift, RMS noise, and obvious interference. |
| 3 | Choose bandwidth and event threshold based on the scientific question. |
| 4 | Verify that conclusions are robust to reasonable filtering choices. |
Typical applications
- Event detection thresholds.
- Comparison across pore systems and instruments.
- Troubleshooting unstable recordings.
Common pitfalls
- Using aggressive filters to hide poor experimental stability.
- Changing filtering parameters between samples without reporting it.
- Treating low-noise data as target-specific evidence without controls.