When converting from an analogue signal to a digital signal, error is unavoidable. An analogue signal is continuous, with ideally infinite accuracy, while the digital signal's accuracy is dependent on the quantization resolution, or number of bits of the analogue to digital converter. The difference between the actual analogue value and approximated digital value due to the "rounding" that occurs while converting is called quantization error. For the Analog Science Fiction and Science Fact publication, see Astounding Magazine. ... The term digital signal is used to refer to more than one concept. ... Quantized signal Digital signal In digital signal processing, quantization is the process of approximating a continuous range of values (or a very large set of possible discrete values) by a relatively-small set of discrete symbols or integer values. ... This article or section should include material from AD converters In electronics, an analog-to-digital converter (abbreviated ADC, A/D, or A to D) is a device that converts continuous signals to discrete digital numbers. ...

Many physical quantities are actually quantized by physical entities. Examples of fields where this limitation applies include electronics (due to electrons), optics (due to photons), and chemistry (due to molecules). This is sometimes known as the "quantum noise limit" of systems in those fields. This is a different manifestation of "quantization error," in which theoretical models may be analog but physics occurs digitally. Around the quantum limit, the distinction between analog and digital quantities vanishes.

See also

• Dither
• Analogue to digital converter
• Quantization
• Quantization noise
• Discretization error

Dither is a form of noise, or erroneous signal or data which is deliberately added to sample data for the purpose of minimizing quantization error. ... This article or section should include material from AD converters In electronics, an analog-to-digital converter (abbreviated ADC, A/D, or A to D) is a device that converts continuous signals to discrete digital numbers. ... Generally, quantization is the state of being constrained to a set of discrete values, rather than varying continuously. ... Quantization noise is a noise error introduced by the analogue to digital conversion (ADC) process in telecommunication systems and signal processing. ... In numerical analysis, computational physics, and simulation, discretization error is error resulting from the fact that a function of a continuous variable is represented in the computer by a finite number of evaluations, for example, on a lattice. ...

External Link

• Signal to quantization noise in quantized sinusoidal - Analysis of quantization error on a sine wave