Fourier Transform - Revision history

Milllo at 19:44, 15 April 2021

2021-04-15T19:44:59Z

2021-04-15T15:53:57Z

2021-04-15T15:38:20Z

2021-04-15T15:01:43Z

2021-04-15T14:59:17Z

2021-04-15T14:10:47Z

2021-04-15T14:04:08Z

2021-04-15T14:03:26Z

2021-04-15T13:55:15Z

2021-04-15T13:53:09Z

← Older revision		Revision as of 19:44, 15 April 2021
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	[[File:ethanol_fid_and_spectrum_modified.jpg\|500px]]		[[File:ethanol_fid_and_spectrum_modified.jpg\|500px]]
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		+	A good way to see the method in action is to use excel and a simple dataset of times and intensities. A description of how to use excel to do FT is given [http://online.sfsu.edu/jtai/downloads/ENGR%20302/Excel.FFT.pdf here], but I will summarize it in case this link disappears:

← Older revision		Revision as of 15:53, 15 April 2021
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	[[File:ethanol_fid_and_spectrum_modified.jpg\|500px]]		[[File:ethanol_fid_and_spectrum_modified.jpg\|500px]]
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−	~~A simple file output of the FID from the instrument is a 2d matrix of data with 2 columns and as many rows as requested for the resolution in the experimental parameters.~~

← Older revision		Revision as of 15:38, 15 April 2021
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	[[File:ethanol_fid_and_spectrum_modified.jpg\|500px]]		[[File:ethanol_fid_and_spectrum_modified.jpg\|500px]]

−	~~The~~ file output of the FID from the instrument is a 2d matrix of data with 2 columns and as many rows as requested for the resolution in the experimental parameters.	+	A simple file output of the FID from the instrument is a 2d matrix of data with 2 columns and as many rows as requested for the resolution in the experimental parameters.

← Older revision		Revision as of 15:01, 15 April 2021
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	[[File:ethanol_fid_and_spectrum_modified.jpg\|500px]]		[[File:ethanol_fid_and_spectrum_modified.jpg\|500px]]
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		+	The file output of the FID from the instrument is a 2d matrix of data with 2 columns and as many rows as requested for the resolution in the experimental parameters.

← Older revision		Revision as of 14:59, 15 April 2021
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	The signal output from an NMR instrument is called a Free Induction Decay (FID) and looks like the image on the left, which is intensity of the signal versus time. A fourier transform algorithm is applied to the signal which converts it to intensity versus frequency and looks like the image on the right:		The signal output from an NMR instrument is called a Free Induction Decay (FID) and looks like the image on the left, which is intensity of the signal versus time. A fourier transform algorithm is applied to the signal which converts it to intensity versus frequency and looks like the image on the right:

−	[[File:~~ethanol_fid_and_spectrum~~.jpg\|500px]]	+	[[File:ethanol_fid_and_spectrum_modified.jpg\|500px]]

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 Fourier Transform does mathematically what our ears do physically: resolve a signal into component frequencies. FT is a method to determine the simple wave components of a mixed wave. The method is theoretically based on calculus, but is actually carried out computationally using numerical analysis.
-The signal output from an NMR instrument is called a Free Induction Decay (FID) and looks like this:
+The signal output from an NMR instrument is called a Free Induction Decay (FID) and looks like the image on the left, which is intensity of the signal versus time. A fourier transform algorithm is applied to the signal which converts it to intensity versus frequency and looks like the image on the right:
 [[File:ethanol_fid_and_spectrum.jpg|500px]]

← Older revision		Revision as of 14:04, 15 April 2021
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	This signal gives intensity of the signal versus time. A fourier transform algorithm is applied to the signal which converts it to intensity versus frequency:		This signal gives intensity of the signal versus time. A fourier transform algorithm is applied to the signal which converts it to intensity versus frequency:

−	[[File:ethanol_fid_and_spectrum.~~png~~\|500px]]	+	[[File:ethanol_fid_and_spectrum.jpg\|500px]]

← Older revision		Revision as of 14:03, 15 April 2021
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	This signal gives intensity of the signal versus time. A fourier transform algorithm is applied to the signal which converts it to intensity versus frequency:		This signal gives intensity of the signal versus time. A fourier transform algorithm is applied to the signal which converts it to intensity versus frequency:

−	[[File:~~proton NMR of ethanol~~.png\|500px]]	+	[[File:ethanol_fid_and_spectrum.png\|500px]]

← Older revision		Revision as of 13:55, 15 April 2021
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	The signal output from an NMR instrument is called a Free Induction Decay (FID) and looks like this:		The signal output from an NMR instrument is called a Free Induction Decay (FID) and looks like this:

−	This signal gives intensity of the signal versus time. A fourier transform algorithm is applied to the signal which converts it to intensity versus frequency.	+	This signal gives intensity of the signal versus time. A fourier transform algorithm is applied to the signal which converts it to intensity versus frequency:
		+
		+	[[File:proton NMR of ethanol.png\|500px]]

← Older revision		Revision as of 13:53, 15 April 2021
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−	Fourier Transform does mathematically what our ears do physically: resolve a signal into component frequencies.	+	Fourier Transform does mathematically what our ears do physically: resolve a signal into component frequencies. FT is a method to determine the simple wave components of a mixed wave. The method is theoretically based on calculus, but is actually carried out computationally using numerical analysis.

−	FT is a ~~method to determine~~ the ~~simple wave components of a mixed wave~~. ~~The method~~ is ~~theoretically based on calculus, but is actually carried out computationally using numerical analysis~~.	+	The signal output from an NMR instrument is called a Free Induction Decay (FID) and looks like this:
		+
		+	This signal gives intensity of the signal versus time. A fourier transform algorithm is applied to the signal which converts it to intensity versus frequency.