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Second Order Discrete-Time System Demonstration

Neil Robertson

Discrete-time systems are remarkable: the time response can be computed from mere difference equations, and the coefficients ai, bi of these equations are also the coefficients of H(z). Here, I try to illustrate this remarkableness by converting a continuous-time second-order system to an approximately equivalent discrete-time system. With a discrete-time model, we can then easily compute the time response to any input. But note that the goal here is as much to understand the discrete-time model as it is to find the response.

A Beginner's Guide To Cascaded Integrator-Comb (CIC) Filters

Rick Lyons

This article discusses the behavior, mathematics, and implementation of cascaded integrator-comb filters.

Stereophonic Amplitude-Panning: A Derivation of the "Tangent Law"

Rick Lyons

This article presents a derivation of the "Tangent Law"

A Brief Introduction To Romberg Integration

Rick Lyons

This article briefly describes a remarkable integration algorithm, called "Romberg integration." The algorithm is used in the field of numerical analysis but it's not so well-known in the world of DSP.

An IIR 'DC Removal' Filter

Rick Lyons
●2 comments

It seems to me that DC removal filters (also called "DC blocking filters") have been of some moderate interest recently on the dsprelated.com Forum web page. With that notion in mind I thought I'd post a little information, from Chapter 13 of my "Understanding DSP" book, regarding infinite impulse response (IIR) DC removal filters.

Two Easy Ways To Test Multistage CIC Decimation Filters

Rick Lyons
●2 comments

This article presents two very easy ways to test the performance of multistage cascaded integrator-comb (CIC) decimation filters. Anyone implementing CIC filters should take note of the following proposed CIC filter test methods.

FFT Interpolation Based on FFT Samples: A Detective Story With a Surprise Ending

Rick Lyons
●4 comments

This blog presents several interesting things I recently learned regarding the estimation of a spectral value located at a frequency lying between previously computed FFT spectral samples. My curiosity about this FFT interpolation process was triggered by reading a spectrum analysis paper written by three astronomers.

An Efficient Linear Interpolation Scheme

Rick Lyons
●4 comments

This article presents a computationally-efficient linear interpolation trick that requires at most one multiply per output sample.

Sinusoidal Frequency Estimation Based on Time-Domain Samples

Rick Lyons
●6 comments

The topic of estimating a noise-free real or complex sinusoid's frequency, based on fast Fourier transform (FFT) samples, has been presented in recent blogs here on dsprelated.com. For completeness, it's worth knowing that simple frequency estimation algorithms exist that do not require FFTs to be performed . Below I present three frequency estimation algorithms that use time-domain samples, and illustrate a very important principle regarding so called "exact" mathematically-derived DSP algorithms.

Launch of Youtube Channel: My First Videos - Embedded World 2017

Stephane Boucher

I went to Embedded World 2017 in Nuremberg with an ambitious plan; I would make video highlights of several exhibits (booths) to be presented to the *Related sites audience.  I would try to make the vendors focus their pitch on the essential...