Kvanttisekoitus

Kvanttisekoitus, also known as quantization noise, is a type of noise that arises due to the discrete nature of digital signals. In digital systems, continuous analog signals are converted into discrete digital values, a process known as quantization. This conversion introduces an error, or noise, because the continuous signal cannot be perfectly represented by a finite number of discrete levels. The difference between the original analog signal and the quantized digital signal is what constitutes quantization noise.

The amount of quantization noise depends on the number of bits used in the quantization process. More bits result in finer quantization steps and less noise, while fewer bits lead to coarser steps and more noise. Quantization noise is a fundamental limitation in digital signal processing and is present in all digital systems, including audio, video, and communication systems.

Quantization noise can be modeled as an additive noise source that is uncorrelated with the input signal. Its power spectral density is typically assumed to be uniform across the frequency band of interest, although in practice, it can exhibit some frequency-dependent characteristics. The power of quantization noise is inversely proportional to the number of quantization levels, which is determined by the number of bits used in the quantization process.

Reducing quantization noise often involves increasing the number of bits used in the quantization process, which can be achieved through techniques such as oversampling and noise shaping. However, these methods also increase the complexity and cost of the digital system. Therefore, there is a trade-off between the desired signal quality and the available resources in digital signal processing systems.