Quantization Noise
Quantization noise is inherent in the
amplitude quantization process and occurs in the analog-to-digital converter,
ADC. The noise is additive and independent of the signal when the number of
levels L >= 16. This is equivalent to B >= 4 bits. (See Section
2.1.) For a signal that has been converted to electrical form and thus has a
minimum and maximum electrical value, eq. is the appropriate formula for
determining the SNR. If the ADC is adjusted so that 0 corresponds to the
minimum electrical value and 2B-1 corresponds to the maximum
electrical value then:
Quantization noise -
For B >= 8 bits, this means a SNR >= 59 dB. Quantization
noise can usually be ignored as the total SNR of a complete system is
typically dominated by the smallest SNR. In CCD cameras this is photon
noise.