Signal Processing

Modems

I’m working on a series of articles on modems. It’ll be a loose collection of posts, and not a true multi-part article such as the one on tomography. Modem technology is not widely known and/or understood, even by a technical audience. However…

Submitted on 13 February 2019

Apply a Filter Twice for Greatly Improved Performance

Figure 3. Impulse response of the filter of Figure 1 convolved with itself.

Say that you have implemented a low-pass FIR filter with the correct cut-off frequency and transition band, but that you are not quite happy with the suppression of frequencies in the stop band. A straightforward trick to put in your toolbox is that you can double the suppression by…

Submitted on 26 February 2018