Why my spectrogram have negative values?
Show older comments
In this figure we have a exponential sine wave and his spectrogram. My question is why the spectrogram have negative values? (from -50 to -150)
Accepted Answer
Star Strider
on 10 Mar 2018
2 votes
Assuming he spectrogram function plots the power spectral density (PSD) in decibels. The values are relative, not negative, amplitudes, so -150 dB corresponds to an amplitude of about 3.2E-8.
More Answers (1)
Kaiwen Zhao
on 14 Mar 2020
1 vote
It's Power/frequency(dB/Hz), using log.
Categories
Find more on Time-Frequency Analysis in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
