Question

How does the delta-sigma-modulation work? I do not know much about this communication-technologie-stuff and can only find explanations for people how study this kind of stuff. Is there somewhere a simple explanation of this sort of stuff?

Answer 1

To understand delta-sigma modulation you must first understand the difference between digital and analog signals. Please visit this article from my blog ( http://tipsfromthetech.blogspot.com/2011/07/part-3-analog-and-digital-signals.html).

Now that you have a little bit better understanding of the difference between the two signals I'll attempt to explain ΣΔ modulation in layperson's term.

As you now know an analog signal is a continuous wave and digital is a series of pulses. Analog signals have (in theoretical terms) have infinite fidelity. When an analog signal is converted to a digital signal some of this fidelity is lost. Think of it like this:
The smooth wave is an analog signal and the jaggy curve that overlays it is the same signal converted to digital. What ΣΔ modulation does is measure the difference between the two signals in order to improve the fidelity of the digital signal. This can also work in the reverse when converting digital to analog. When going from analog to digital, digital modulation is used (typically through software). When going from digital to analog, voltage modulation is used (typically through hardware).

There is really a lot more to it than this, but a lot of the other factors and things involved get rather technical. This is just a dumbed down explanation that hopefully you can understand. Hope it helps.