Question

Explain the concept of dithering in signal processing.

Answer 1

Dithering is a technique used in signal processing to mitigate the quantization error that occurs when converting a continuous analog signal into a discrete digital representation. This error arises because digital systems have a finite number of levels to represent the continuous range of signal values accurately. Dithering introduces controlled randomness or noise to the signal before quantization, which helps distribute the quantization error more evenly across the signal's range and improves the overall fidelity of the digital representation.

Here's how dithering works:

Quantization Error: When an analog signal is converted into a digital signal, the continuous range of signal values is mapped onto a discrete set of levels. This mapping process inherently introduces errors, known as quantization errors. These errors manifest as small deviations between the original analog signal and its digital representation.

Adding Controlled Noise: Dithering adds a small amount of controlled noise to the analog signal before quantization. This noise is intentionally introduced and usually follows a carefully chosen statistical distribution, often uniform or triangular. The added noise is generally of very low amplitude