Motivation Delta-sigma modulation

1 motivation

1.1 why convert analog signal stream of pulses?
1.2 why delta-sigma modulation?
1.3 why delta-sigma analog digital conversion?

motivation
why convert analog signal stream of pulses?

in brief, because easy regenerate pulses @ receiver ideal form transmitted. part of transmitted waveform required @ receiver time @ pulse occurred. given timing information, transmitted waveform can reconstructed electronically great precision. in contrast, without conversion pulse stream transmitting analog signal directly, noise in system added analog signal, permanently reducing quality.

each pulse made of step followed after short interval step down. possible, in presence of electronic noise, recover timing of these steps , regenerate transmitted pulse stream noiselessly. accuracy of transmission process reduces accuracy transmitted pulse stream represents input waveform.

why delta-sigma modulation?

delta-sigma modulation converts analog voltage pulse frequency , can understood pulse-density modulation or pulse-frequency modulation depending on implementation. in general, frequency may vary smoothly in infinitesimal steps, may voltage, , both may serve analog of infinitesimally varying physical variable such acoustic pressure, light intensity, etc. substitution of frequency voltage entirely natural , carries in train transmission advantages of pulse stream.

why delta-sigma analog digital conversion?

the adc converts mean of analog voltage mean of analog pulse frequency , counts pulses in known interval pulse count divided interval gives accurate digital representation of mean analog voltage during interval. interval can chosen give desired resolution or accuracy. method cheaply produced modern methods , used.