Using the DFT - Revision history

Baldwin.britton at 18:18, 27 November 2007

2007-11-27T18:18:28Z

← Older revision		Revision as of 11:18, 27 November 2007
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	This is what we get when we sample the signal at 3Hz		This is what we get when we sample the signal at 3Hz

	[[Image:hw13_1.jpg]]		[[Image:hw13_1.jpg]]


	Taking the original signal <math>sin(2pit)</math> and applying the DFT we get this graph:		Taking the original signal <math>sin(2pit)</math> and applying the DFT we get this graph:

	[[Image:Signals-13.jpg]]		[[Image:Signals-13.jpg]]


	Now taking the DFT of this sampled signal, we get a graph like this:		Now taking the DFT of this sampled signal, we get a graph like this:

	[[Image:hw13_2.jpg]]		[[Image:hw13_2.jpg]]

2007-11-27T18:18:10Z

← Older revision		Revision as of 11:18, 27 November 2007
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	[[Image:hw13_1.jpg]]		[[Image:hw13_1.jpg]]


			Taking the original signal <math>sin(2pit)</math> and applying the DFT we get this graph:
			[[Image:Signals-13.jpg]]


			Now taking the DFT of this sampled signal, we get a graph like this:
			[[Image:hw13_2.jpg]]


	~~Taking the original signal <math>sin(2pit)</math> and applying the DFT we get this graph:~~

	~~[[Image:Signals-13.jpg]]~~

2007-11-27T18:13:56Z

← Older revision		Revision as of 11:13, 27 November 2007
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	~~sampling <math>sin(2pit)</math> and taking the DFT~~ we get ~~this graph~~:		This is what we get when we sample the signal at 3Hz
			[[Image:hw13_1.jpg]]

	~~[[Image:Signals-13.jpg]]~~


			Taking the original signal <math>sin(2pit)</math> and applying the DFT we get this graph:

			[[Image:Signals-13.jpg]]

2007-11-27T18:11:11Z

← Older revision		Revision as of 11:11, 27 November 2007
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	clear all;		clear all;

	t=0:.01:2;		t=0:.01:2;

	T=1/3;		T=1/3;

	ts=0:T:2;		ts=0:T:2;

	f1=2;		f1=2;

	f2=1/0.125;		f2=1/0.125;

	x = sin(2pits); %this is the function		x = sin(2pits); %this is the function

	plot(ts,sin(2pits),'r-',t,sin(2pit)); % plot the original signal and the signal sampled at 3Hz		plot(ts,sin(2pits),'r-',t,sin(2pit)); % plot the original signal and the signal sampled at 3Hz

	X = fft(x); % take the DFT		X = fft(x); % take the DFT

	pause (2);		pause (2);

	plot (ts,X); %plot the DFT of the signal sampled at 3Hz		plot (ts,X); %plot the DFT of the signal sampled at 3Hz

	pause (4);		pause (4);

	x=sin(2pit);		x=sin(2pit);

	plot(t,x);		plot(t,x);

	pause(2);		pause(2);

	X = fft(x);		X = fft(x);

	plot(t,X); %plot the DFT of the original signal		plot(t,X); %plot the DFT of the original signal

2007-11-27T18:09:19Z

← Older revision		Revision as of 11:09, 27 November 2007
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	[[Image:Signals-13.jpg]]		[[Image:Signals-13.jpg]]





	Script for matlab:		Script for matlab:

	~~<pre>~~
	clear all;		clear all;
	t=0:.01:1;		t=0:.01:2;
	T=~~0.20~~;		T=1/3;
	ts=0:T:1;		ts=0:T:2;
	f1=2;		f1=2;
	f2=1/0.125;		f2=1/0.125;
	x = sin(2pi~~3*t~~); %this is the function		x = sin(2pits); %this is the function
	plot(t,x); % plot the original signal		plot(ts,sin(2pits),'r-',t,sin(2pit)); % plot the original signal and the signal sampled at 3Hz
	X = fft(x); % take the DFT		X = fft(x); % take the DFT
	pause (2);		pause (2);
	plot (t,X); %plot the DFT of the signal		plot (ts,X); %plot the DFT of the signal sampled at 3Hz
	~~</pre>~~		pause (4);
			x=sin(2pit);
			plot(t,x);
			pause(2);
			X = fft(x);
			plot(t,X); %plot the DFT of the original signal

2007-11-12T18:50:51Z

← Older revision		Revision as of 11:50, 12 November 2007
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	Script for matlab:		Script for matlab:

			<pre>
	clear all;		clear all;

	t=0:.01:1;		t=0:.01:1;

	T=0.20;		T=0.20;

	ts=0:T:1;		ts=0:T:1;

	f1=2;		f1=2;

	f2=1/0.125;		f2=1/0.125;

	x = sin(2pi3*t); %this is the function		x = sin(2pi3*t); %this is the function

	plot(t,x); % plot the original signal		plot(t,x); % plot the original signal

	X = fft(x); % take the DFT		X = fft(x); % take the DFT

	pause (2);		pause (2);

	plot (t,X); %plot the DFT of the signal		plot (t,X); %plot the DFT of the signal
			</pre>

2007-11-12T18:44:30Z

← Older revision		Revision as of 11:44, 12 November 2007
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	sampling <math>sin(2pit)</math> and taking the DFT we get this graph:		sampling <math>sin(2pit)</math> and taking the DFT we get this graph:

	[[Image:Signals-13.jpg]]		[[Image:Signals-13.jpg]]

2007-11-12T18:43:52Z

← Older revision		Revision as of 11:43, 12 November 2007
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	sampling <math>sin(2pit)</math> and taking the DFT we get this graph:		sampling <math>sin(2pit)</math> and taking the DFT we get this graph:
			[[Image:Signals-13.jpg]]

2007-11-12T18:42:45Z

← Older revision		Revision as of 11:42, 12 November 2007
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	sampling <math>sin(2pit)</math> and taking the DFT we get this ~~graf~~:		sampling <math>sin(2pit)</math> and taking the DFT we get this graph:


	Script for matlab:		Script for matlab:

2007-11-12T18:42:24Z

← Older revision		Revision as of 11:42, 12 November 2007
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			sampling <math>sin(2pit)</math> and taking the DFT we get this graf:

	Script for matlab:		Script for matlab:
	clear all;		clear all;