Videos and user manual

2.4. Frequency and Harmonic Analysis

In this chapter, we'll be looking at the frequencies and harmonies calculated from the waveform. We remain in the biomarker space, i.e. in the technical list.

To begin, open the frequencies. You'll see a display between 0 and 60 Hz. At the top of this display, you'll find the lowest frequencies, i.e. the very low frequencies below 0.03 Hz, the low frequencies, and the high frequencies around 0.4 Hz. These frequency ranges generally contain very interesting information.

We look first at the 0-3 Hz range, but it's also possible to find information on the other frequency bands.

Next, move on to the Harmonic section. This section performs a calculation on the frequencies to determine which are the strongest. The information obtained here is also relevant to the various biomarkers. This technical analysis allows you to scan the recording and identify the predominant frequencies.  It is difficult to distinguish relevant information with the naked eye on these displays, but it is one of the bases of what the application uses to calculate biomarkers... 

FFT (Fast Fourier Transform) is an algorithm that calculates the Fourier transform quickly and efficiently. It is widely used in signal processing, spectral analysis and data compression. The Fourier transform is a mathematical tool that decomposes a function or signal into a sum of sinusoids of different frequencies. It transforms a signal from the time domain to the frequency domain.