FIR Filter Design Calculator
Interactive FIR Filter Design Calculator for signal processing engineers. Design FIR filters with ease and precision.
How to use
Provide the filter order, cutoff frequency, and sampling rate. The calculator produces windowed sinc coefficients (Hamming) for the specified FIR filter.
Methodology
We build coefficients using the normalized sinc function and apply a Hamming window to shape the frequency response.
- Normalized cutoff = cutoff / sample rate.
- Coefficients count = order + 1.
- Windowed sinc uses the Hamming window.
Full original guide (expanded)
The original page references MathWorks guidance for FIR filter design and discusses standard signal processing workflows for generating coefficients.
h[n] = 2fc × sinc(2fc(n - M/2)) × w[n]
Glossary
- Filter Order: Number of taps minus one.
- Cutoff Frequency: Threshold frequency.
- Sample Rate: Sampling frequency.
- Coefficients: Impulse response values.
Example
An order 20 filter with 1 kHz cutoff at 48 kHz generates 21 coefficients symmetrically shaped by the Hamming window.
FAQ
What is an FIR filter?
A filter with a finite impulse response defined by coefficients.
How do I design one?
Select order and cutoff, then compute coefficients via sinc-based formulas.
Why use Hamming window?
It controls sidelobes and smooths transitions.