Undersampling GUI

Understand Undersampling easily with appropriate spectra plots and tables.

This GUI was designed to help users to better understand the Undersampling/Bandpass Sampling technique. While you're urged to follow the above link, to better understand this topic, a brief explanation follows:

All of us, dealing with signal processing are familiar with the Nyquist–Shannon sampling theorem. According to it, in order to achieve proper sampling (and avoid aliasing) the sampling frequency must be at least two times the bandwidth of a bandlimited signal.

From my experience most engineers tend to neglect the fact that Harry Nyquist theorem relates to Bandlimited signal, while keeping in mind just that in order to properly sample a signal with highest frequency f the sampling rate should be at least 2f. So do we need 11GHz sampling frequency to work with Wi-Fi? And in case of WiGig ~60 [GHz] signal we will need 120 [GHz] sampling rate? Fortunately this is not the case. In case of a signal whose Bandwidth in much lower than it's frequency BW/f << 1 we can sample it with frequencies much lower than Nyquist rate. Actually we can sometimes achieve sample rate of about 2BW which, in case of WiGig signal will be about 3 [GHz instead of 120 [GHz].

See Help for GUI usage instructions. You are more then welcome to comment, reports issues and ask for features you consider interesting.

Hope you will find this useful,

Nikolay.

Version info:

Version No': 1.03 Release date: 25/03/2011

Changes list:

•First version released to public