Pulse code modulation converts analog to digital.
Pulse Code Modulation: sample, quantise and encode analog signals into bits. Telephone PCM: 8 kHz×8 bits=64 kbit/s using μ-law/A-law companding. Variants: DPCM, delta modulation, ADPCM reduce rate. Foundation of digital telephony and audio.
CD audio is PCM: 44.1 kHz×16 bit×2 channels = 1.41 Mbit/s.
Pulse code modulation converts analogue signals to digital bits, which is the foundation of digital telephony and audio.
Pulse code modulation converts analog to digital.
Pulse code modulation converts analogue signals to digital bits, which is the foundation of digital telephony and audio.
Sampling, quantising and encoding into binary code words for transmission.
It captures the important speech band, which is up to about 3.4 kHz, with a margin for anti-alias filtering.
Typical applications include sampling a voice signal at 8 kHz with 8 bits for telephony, creating a digital audio file from a microphone and encoding a sensor signal for transmission over a digital link.
Study "Shannon capacity" first (topic 78 of 101 in Signals, Control & Comms). It covers the groundwork this topic builds on.
Companding. T1/E1 carrier. Quantisation noise.
CD audio is PCM: 44.1 kHz×16 bit×2 channels = 1.41 Mbit/s.
The next topic is "Digital modulation", which builds directly on this one.
It is classed as Advanced in Signals, Control & Comms (topic 79 of 101). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Signals, Control & Comms.
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