Unit of P1 in fft spectrum

2 次查看(过去 30 天)
Samyak Mohapatra
Samyak Mohapatra 2019-4-18
编辑: Shubham 2024-10-15
What is the unit of P1 in fft manual of MATLAB? It's written Amplitude spectrum, but these amplitudes are much smaller than the ampliudes of the original signal. Can we convert it to dB?
Thanks.

回答(1 个)

Shubham
Shubham 2024-10-15
编辑:Shubham 2024-10-15
Hey Samyak,
In the context of the FFT (Fast Fourier Transform) in MATLAB, the unit of P1 is Amplitude spectrum. The fft function includes a scaling factor L between the original and the transformed signals. The signal is then rescaled upon dividing by the same scaling factor (L).
Refer to the following documentation for fft here.
To convert the amplitude spectrum to decibels (dB), you can use the following formula:
P1_dB = 20 * log10(P1);
This conversion will give you the amplitude spectrum in dB, which is a logarithmic scale commonly used in signal processing. Refer to this MATLAB Answer post as an example.
I hope this helps!

类别

Help CenterFile Exchange 中查找有关 Fourier Analysis and Filtering 的更多信息

产品


版本

R2017b

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by