Aditya Dua Blog on DSPRelated.com

Filtering Noise: The Basics (Part 1)

Aditya Dua — Sat, 17 Sep 2022 23:00:07 +0000

Introduction

Finding signals in the presence of noise is one of the fundamental quests of the discipline of signal processing. Noise is inherently random by nature, so a probability oriented approach is needed to develop a mathematical framework for filtering (i.e. removing/suppressing) noise. This framework or discipline, formally referred to as stochastic signal processing, is often...

Smaller DFTs from bigger DFTs

Aditya Dua — Tue, 22 Jan 2019 06:49:37 +0000

Introduction

Let's consider the following hypothetical situation: You have a sequence $x$ with $N/2$ points and a black box which can compute the DFT (Discrete Fourier Transform) of an $N$ point sequence. How will you use the black box to compute the $N/2$ point DFT of $x$? While the problem may appear to be a bit contrived, the answer(s) shed light on some basic yet...