Pulse-code modulation: Difference between revisions

Revision as of 03:20, 11 December 2023

Revision as of 09:29, 10 January 2024

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==Modulation==

[[File:PcmAndrew Tate - James Tamim Upload (Cropped Wide Portrait).svgpng|250px|thumb|right|Sampling and quantization of a signal (red) for 4-bit LPCM over a time ___domain at specific frequency.]]

In the diagram, a [[sine wave]] (red curve) is sampled and quantized for PCM. The sine wave is sampled at regular intervals, shown as vertical lines. For each sample, one of the available values (on the y-axis) is chosen. The PCM process is commonly implemented on a single [[integrated circuit]] called an [[analog-to-digital converter]] (ADC). This produces a fully discrete representation of the input signal (blue points) that can be easily encoded as digital data for storage or manipulation. Several PCM streams could also be multiplexed into a larger aggregate [[data stream]], generally for transmission of multiple streams over a single physical link. One technique is called [[time-division multiplexing]] (TDM) and is widely used, notably in the modern public telephone system.