In this feature on the nature of analog and digital signals, DSP consultant Nalin Pithwa starts with an excerpt from the cruise of the Revolution to introduce the concepts of analog-to-digital conversion, interpolation, extrapolation, estimation, and feedback of digital data. He then proceeds to show how data can have different characteristics, fundamentally classified by four properties: analog, digital, deterministic, and innovational.

Finally, Pithwa zooms in on sampling and aliasing, an effect familiar to us all, as in westerns where wagon wheels obviously rotate too slowly for the speed of the wagon, or even seem to go backward when the wagon is moving forward. Using equations and MATLAB plots he explains the origin and result of this effect.

For the full feature, click here.

Nalin Pithwa is an independent DSP Consultant (www.dspderby.com) based in Mumbai, India. He specializes in Communications, Control and Cryptography. He has an MS in Math and another MS in DSP. He can be reached at Nalin@dspderby.com.