SINADR

Signal-to-noise and distortion ratio (SINADR) is a measurement of the purity of a signal. SINADR is typically used in data converter specifications. SINADR is defined as:

$\mathrm{S}\mathrm{I}\mathrm{N}\mathrm{A}\mathrm{D}\mathrm{R}=\frac{P_{\mathrm{s}\mathrm{i}\mathrm{g}\mathrm{n}\mathrm{a}\mathrm{l}}}{P_{\mathrm{q}\mathrm{u}\mathrm{a}\mathrm{n}\mathrm{t}\mathrm{i}\mathrm{z}\mathrm{a}\mathrm{t}\mathrm{i}\mathrm{o}\mathrm{n}\mathrm{E}\mathrm{r}\mathrm{r}\mathrm{o}\mathrm{r}}+P_{\mathrm{r}\mathrm{a}\mathrm{n}\mathrm{d}\mathrm{o}\mathrm{m}\mathrm{N}\mathrm{o}\mathrm{i}\mathrm{s}\mathrm{e}}+P_{\mathrm{d}\mathrm{i}\mathrm{s}\mathrm{t}\mathrm{o}\mathrm{r}\mathrm{t}\mathrm{i}\mathrm{o}\mathrm{n}}}$

where $P$ is the average power of the signal, quantization error, random noise and distortion components. SINADR is usually expressed in dB. SINADR is a standard metric for analog-to-digital converter and digital-to-analog converter.

SINADR (in dB) is related to ENOB by the following equation:

$\mathrm{S}\mathrm{I}\mathrm{N}\mathrm{A}\mathrm{D}\mathrm{R}=ENOB\cdot 6.02+1.76$

See also

• Signal-to-noise ratio