Signal Processing & DSP

Basic

Decibel (Power Ratio)

Express a power ratio in decibels.

Formula

L = 10\log_{10}\!\left(\frac{P_2}{P_1}\right)

Variables

LLevel (dB)

P_1Reference power

P_2Measured power

Example

P_2 = 100×P_1: L = 20 dB

Did You Know?

Decibels turn the vast range of real-world power levels into a compact, addable scale.

dsp decibel power

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More in Signal Processing & DSP

Nyquist Rate

Sample at least twice the highest frequency to avoid aliasing.

FFT Bin Frequency

Frequency represented by the k-th bin of an N-point FFT.

Frequency Resolution

Spacing between adjacent FFT bins.

Signal-to-Noise Ratio

Ratio of signal power to noise power, in decibels.

Quantisation SNR

Best possible SNR (dB) of an ideal b-bit converter.

Decibel (Amplitude Ratio)

Express a voltage/amplitude ratio in decibels.