Quiz 2 Flashcards
Describe Fourier transforms
Converts signals from the time domain to the frequency domain to reveal the frequency components of the signal
Describe signal filtering
extract specific components from a signal while removing unwanted components
explain oversampling
taking measurements at a frequency much higher than the highest frequency. reduces random noise, not periodic noise.
Explain RMS
It is a way to average signals while considering sign and magnitude. it is the DC equivalent of an AC signal.
Explain filter types
low pass removes high frequency signals. high pass removes low frequency signals. band pass extracts a specific range. they all remove periodic noise.
explain roll-off
rate that a filter changes from its pass band to its stop band. -3dB from the signal peak
explain how filter order affects things
higher order filters have steeper roll-offs and have a delay due to the increased equations
explain strain gauges
measure strain using piezoresistive principles. read with a wheatstone bridge
explain the seebeck effect
a voltage difference is created across two dissimilar metals between a hot junction and cold junction
explain the peltier effect
it is the reverse of the seebeck effect. electric current absorbs or emits heat across the metal differently based on the composition of the metal
explain cold junction compensation
method to calculate the difference between the hot junction and cold junction. calibrates the cold junction to 0C.
explain infrared sensors
measures heat emitted from all objects based on the molecular movement of everything above absolute zero. it is not visible because the wavelength is not within our visible spectrum.
explain the types of strain gauges
quarter bridge, half bridge, full bridge. increases from least sensitive to most sensitive.
