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Derive the expression for signal to quantization noise ratio in PCM.
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written 5.2 years ago by | • modified 5.2 years ago |
The SQNR reflects the relationship between the maximum nominal signal strength and the quantization error (also known as quantization noise) introduced in the analog-to-digital conversion.
The SQNR formula is derived from the general SNR (Signal-to-Noise Ratio) formula for the binary pulse-code modulated communication channel:
$\mathrm{SNR}=\frac{3 \times 2^{2n}}{1+4P_e \times (2^{2n} - 1)} \frac{m_m(t)^2}{m_p(t)^2}$
where
$ P_{e}$ is the probability of received bit error
$m_{p}(t)$ is the peak message signal level
$m_{m}(t) $ is the mean message signal level
As SQNR applies to quantized signals, the formulae for SQNR refer to discrete-time digital signals.