FFT Analyzer Basic FAQ

An FFT analyzer is an electrical measuring instrument primarily used for digital frequency analysis of low-frequency bands using FFT technology, and in a broad sense, it is a type of spectrum analyzer. (Note: Since "spectrum" is the more common term when adding "analyzer," we will use this term here.)

Spectrum analyzers, in the sense of converting time-domain signals into frequency spectra, can be broadly divided into the following two types:

[1] obtains the frequency spectrum by sweeping the frequency of a local oscillator that mixes with the input signal, while [2] simultaneously converts the time-domain data, which has been converted into digital data by an A/D converter, into spectral values in a certain frequency band. Recently, high-frequency spectrum analyzers of [1] that utilize FFT technology have also been released.

Recent FFT analyzers not only offer frequency analysis capabilities but also analysis functions in the time and amplitude domains, giving them the characteristics of comprehensive digital signal processing instruments for low-frequency signals. In addition, there are 1/N octave analyzers, which are low-frequency spectral analyzers used for analyzing acoustic vibration data.