For example, Figure 2.1 displays the vibration time-history for a car’s floor panel measured by an accelerometer. The mean-square value (power) is a convenient measurement of signal strength. For example, they may refer to the PSD of an acceleration signal as the acceleration spectral density. The name power spectral density does not include the measured quantity, so engineers sometimes replace the word power with the name of the measurement. For example, for a signal with an acceleration measurement in unit G, the PSD units are G 2/Hz. It represents the distribution of a signal over a spectrum of frequencies similar to a rainbow that represents the distribution of light over a spectrum of wavelengths (colors).ĭensity: The magnitude of the PSD is normalized to a single hertz (Hz) bandwidth. Spectral: The PSD is a function of frequency. In this case, “power” does not refer to a physical quantity, such as watts or horsepower. For example, if a test engineer measures acceleration over time, then the mean of the squared acceleration values is the power of the PSD. Power: A signal’s mean-square value determines the PSD’s magnitude, meaning how far, on average, it strays from zero. PSD BreakdownĮach word in “power spectral density” represents an essential component of the PSD. In vibration testing, the PSD graph is the most common tool for analyzing random vibration. The power spectral density (PSD) estimates the distribution of a signal’s strength over a frequency spectrum.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |