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This demonstration shows various signals interfered by noise. Evaluate the signal quality!
- The more the interfered signal (yellow) differs from the original signal (green) the less is the signal quality.
- It's the relative difference not the absolute that matters.
Thus, the signal quality is measured as the ratio of signal power to noise power: Signal-to-noise ratio (SNR).
The Signal-to-noise ratio is usually measured in decibels (dB).
Launch the app and try out how different signals will be interfered by noise depending on the S/N-ratio.
| SNR | Sine wave | Audio signal |
|---|---|---|
| 20 dB |  |
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| 10 dB |  |
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| 6 dB |  |
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| 3 dB |  |
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| 0 dB |  |
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Sine wave and audio signals with SNR = 20 dB, 10dB, 6 dB, 3 dB and 0 dB. Noise bandwidth is 1000 Hz.
See also
The same scenarios with a noise bandwidth 200 Hz are shown is this experiment: Noise bandwidth demonstration.
A signal x(t) is superimposed by noise.
Adjust the signal-to-noise ratio (SNR) and produce different signal qualities. Analyze the impact of Gaussian noise on the selected signal.
- See how the interfered signal (yellow) differs from the original signal (green).
- Listen to the interfered sound signal.
Further interactive options:
- Click on source: Audio or signal generator waveforms can be selected.
- Click on filter: Noise bandwidth can be set. See also SNR and noise bandwidth demonstration