Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Upsampling

Upsampling

Managing signal sampling rates is essential in digital signal processing to maintain signal integrity. A decimated signal, characterized by a reduced frequency range due to its lower sampling rate, can be upsampled by inserting zeros between each sample. This upsampling process expands the original spectrum and introduces repeated spectral replicas at intervals dictated by the new Nyquist frequency. To refine this zero-inserted sequence, it is passed through a lowpass filter with a cutoff...

Downsampling

Downsampling

When considering a sampled sequence with zero values between sampling instants, one can replace it by taking every N-th value of the sequence. At these integer multiples of N, the original and sampled sequences coincide. This process, known as decimation, involves extracting every N-th sample from a sequence, thereby creating a more efficient sequence.
The Fourier transform of the decimated sequence reveals a combination of scaled and shifted versions of the original spectrum. This...

Reconstruction of Signal using Interpolation

Reconstruction of Signal using Interpolation

Signal processing techniques are essential for accurately converting continuous signals to digital formats and vice versa. When a continuous signal is sampled with a period T, the resulting sampled signal exhibits replicas of the original spectrum in the frequency domain, spaced at intervals equal to the sampling frequency. To handle this sampled signal, a zero-order hold method can be applied, which creates a piecewise constant signal by retaining each sample's value until the next sampling...

Aliasing

Aliasing

Accurate signal sampling and reconstruction are crucial in various signal-processing applications. A time-domain signal's spectrum can be revealed using its Fourier transform. When this signal is sampled at a specific frequency, it results in multiple scaled replicas of the original spectrum in the frequency domain. The spacing of these replicas is determined by the sampling frequency.
If the sampling frequency is below the Nyquist rate, these replicas overlap, preventing the original signal...

Linear Approximation in Time Domain

Linear Approximation in Time Domain

Nonlinear systems often require sophisticated approaches for accurate modeling and analysis, with state-space representation being particularly effective. This method is especially useful for systems where variables and parameters vary with time or operating conditions, such as in a simple pendulum or a translational mechanical system with nonlinear springs.
For a simple pendulum with a mass evenly distributed along its length and the center of mass located at half the pendulum's length, the...

Convergence of Fourier Series

Convergence of Fourier Series

The Fourier series is a powerful mathematical tool for representing periodic signals as an infinite sum of complex exponentials. In practice, this infinite series is truncated to a finite number of terms, yielding a partial sum. This truncation makes the approximation of the signal feasible but introduces certain challenges, particularly near discontinuities, known as the Gibbs phenomenon.
The Gibbs phenomenon refers to the persistent oscillations and overshoots that occur near discontinuities...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

When Pneumonia Leads to Sepsis: Clinical Phenotypes and Therapeutic Challenges.

Anaesthesia, critical care & pain medicine·2026

Same author

Robotic partial nephrectomy is inching toward the gold standard for small renal masses-a narrative review.

Translational andrology and urology·2026

Same author

Road safety policies and motor vehicle fatalities in Ecuador: a geographical and temporal analysis from 1990 to 2022.

BMJ public health·2026

Same author

Hantavirus infection: A narrative review focusing on epidemiology, diagnosis, infection control and treatment in the era of globalisation.

Medicina intensiva·2026

Same author

Perioperative antibiotic prophylaxis, prostate size and transperineal prostate biopsy.

BJUI compass·2026

Same author

Human disturbance, preys and refuge cover shape top predator movements in anthropogenic landscapes.

Behavioral ecology : official journal of the International Society for Behavioral Ecology·2026

Search research articles

Related Experiment Video

Updated: Jul 19, 2026

Quantifying Cytoskeleton Dynamics Using Differential Dynamic Microscopy

Quantifying Cytoskeleton Dynamics Using Differential Dynamic Microscopy

Published on: June 15, 2022

Improving accuracy by subpixel smoothing in the finite-difference time domain.

A Farjadpour¹, David Roundy, Alejandro Rodriguez

¹Center for Materials Science and Engineering and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. ardfar@mit.edu

|September 27, 2006

Summary

Accurate modeling of discontinuous dielectric materials using finite-difference time-domain (FDTD) methods is improved with subpixel smoothing. A new scheme based on perturbation theory achieves quadratic convergence for sloped interfaces.

More Related Videos

Time Multiplexing Super Resolving Technique for Imaging from a Moving Platform

Time Multiplexing Super Resolving Technique for Imaging from a Moving Platform

Published on: February 12, 2014

Related Experiment Videos

Last Updated: Jul 19, 2026

Quantifying Cytoskeleton Dynamics Using Differential Dynamic Microscopy

Quantifying Cytoskeleton Dynamics Using Differential Dynamic Microscopy

Published on: June 15, 2022

Time Multiplexing Super Resolving Technique for Imaging from a Moving Platform

Time Multiplexing Super Resolving Technique for Imaging from a Moving Platform

Published on: February 12, 2014

Area of Science:

Computational electromagnetics
Numerical methods for wave propagation

Background:

Finite-difference time-domain (FDTD) methods are widely used for electromagnetic simulations.
Discretization in FDTD leads to reduced accuracy when modeling discontinuous dielectric materials.

Purpose of the Study:

To improve the accuracy of FDTD methods for discontinuous dielectric materials.
To develop and validate a novel subpixel smoothing scheme for dielectric functions.

Main Methods:

Development of a subpixel smoothing scheme based on perturbation theory.
Comparison of the new scheme with existing FDTD smoothing methods.
Analysis of convergence properties for arbitrarily sloped interfaces.

Main Results:

The proposed subpixel smoothing scheme significantly improves accuracy.
The new scheme consistently achieves smaller errors compared to other methods.
The scheme demonstrates quadratic convergence with resolution for sloped interfaces.

Conclusions:

A properly designed subpixel smoothing scheme is crucial for accurate FDTD modeling of dielectric discontinuities.
The developed scheme offers superior accuracy and convergence properties.
Further considerations are needed for sharp dielectric corners.