---
title: whiteNoise
framework: sensorkit
role: symbol
role_heading: Instance Property
path: sensorkit/srphotoplethysmogramopticalsample/noiseterms-swift.struct/whitenoise
---

# whiteNoise

An estimate of the white noise of the sensor.

## Declaration

```swift
let whiteNoise: Double
```

## Discussion

Discussion This value represents the white noise variance estimate per Hz in the normalizedReflectance signal (Normalized Units²/Hz). Apply the noise equivalent bandwidth factor to account for in-band noise for your setup.

## See Also

### Accessing noise terms

- [pinkNoise](sensorkit/srphotoplethysmogramopticalsample/noiseterms-swift.struct/pinknoise.md)
- [backgroundNoise](sensorkit/srphotoplethysmogramopticalsample/noiseterms-swift.struct/backgroundnoise.md)
- [backgroundNoiseOffset](sensorkit/srphotoplethysmogramopticalsample/noiseterms-swift.struct/backgroundnoiseoffset.md)