Calculadora de Resolución FFT Gratis

Calcula la resolución frecuencial de la FFT según la tasa de muestreo y el número de puntos.

Hz

Typically a power of 2

Frequency Resolution

46.875 Hz

Useful Frequency Bins513
Maximum Frequency24,000 Hz
Time Window Duration21.33 ms

Frequency Resolution vs Sampling Rate

Fórmula

## FFT Frequency Resolution The FFT converts time-domain data into frequency-domain bins. The resolution depends on how long you observe the signal. ### Formulas **Frequency Resolution = Sample Rate / FFT Size** **Time Window = FFT Size / Sample Rate** **Useful Bins = FFT Size / 2 + 1** (for real signals) ### Trade-off Better frequency resolution requires longer observation windows. This is the time-frequency uncertainty principle. - Larger FFT = finer frequency resolution but slower updates - Smaller FFT = coarser resolution but faster updates

Ejemplo Resuelto

1024-point FFT at 48 kHz sampling rate.

  1. 01Resolution: 48,000 / 1,024 = 46.875 Hz
  2. 02Useful bins: 1024/2 + 1 = 513
  3. 03Max frequency: 48,000 / 2 = 24,000 Hz
  4. 04Time window: 1024/48,000 x 1000 = 21.33 ms

Preguntas Frecuentes

Why must FFT size be a power of 2?

The Cooley-Tukey FFT algorithm requires powers of 2 for efficiency (O(N log N) vs O(N^2)). Some implementations support other sizes.

How do I improve frequency resolution?

Increase the FFT size (longer time window) or use zero-padding. Note: zero-padding interpolates but does not add actual resolution.

What is spectral leakage?

Signals that do not fit exactly into the FFT window spread energy across adjacent bins. Window functions (Hann, Hamming) reduce leakage.

Aprender

Ohm's Law Guide

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