Skip to main content

Duration: 00:02:08
Release Date: 4/1/2021

What is Alias Free Zone and How Does it Calculate?

In VNAs the bandwidth is limited when the Fourier transform is done from band limited frequency samples. The transformation is a periodic signal in time domain which is a continuous signal. Measurements are accurate if maintained in the alias free range which is the inverse of the step frequency divided by 2. The smaller the step frequency gives you a wider alias free range, whereas the wider the bandwidth will give you a finer resolution. This video shows the frequency starts at 10 MHz to 20 GHz with 2000 points that translates to a 10 MHz step frequency. In this case the alias free range is 50 ns. This video will go into more details on the alias free range and calculations.