fourrier example. fourier series a fourier series is an expansion of a periodic function in terms of...

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Fourrier example

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Page 1: Fourrier example. Fourier series A Fourier series is an expansion of a periodic function in terms of an infinite sum of sines and cosines.sinescosines

Fourrier example

Page 2: Fourrier example. Fourier series A Fourier series is an expansion of a periodic function in terms of an infinite sum of sines and cosines.sinescosines

Fourier series

• A Fourier series is an expansion of a periodic function in terms of an infinite sum of sines and cosines.

Page 3: Fourrier example. Fourier series A Fourier series is an expansion of a periodic function in terms of an infinite sum of sines and cosines.sinescosines

• The computation Fourier series is known as harmonic analysis

• a way to break up an arbitrary periodic function into a set of simple terms that can be plugged in, solved individually

• then recombined to obtain the solution to the original problem or an approximation to it to whatever accuracy is desired or practical.

Page 4: Fourrier example. Fourier series A Fourier series is an expansion of a periodic function in terms of an infinite sum of sines and cosines.sinescosines

Fourrier example

We will set the values as follows: A = 4 volts, T = 1 second. Also, it is given that the width of a single pulse is T/2. Find the rectangular Fourier series of this signal?

Page 5: Fourrier example. Fourier series A Fourier series is an expansion of a periodic function in terms of an infinite sum of sines and cosines.sinescosines

• First, we can see clearly that this signal does have a DC value: the signal exists entirely above the horizontal axis.

• Next, we can see that if we remove the DC component (shift the signal downward till it is centered around the horizontal axis), that our signal is an odd signal.

• This means that we will have an terms, but no bn terms.

Page 6: Fourrier example. Fourier series A Fourier series is an expansion of a periodic function in terms of an infinite sum of sines and cosines.sinescosines

1. DC value (must calculate a0 )

2. Its an Odd Function so (bn = 0 for n > 0)

Bn =0 for all n>0

Page 7: Fourrier example. Fourier series A Fourier series is an expansion of a periodic function in terms of an infinite sum of sines and cosines.sinescosines

3. Calculate an

F(t)= 0 for 0 >t>-t/2

4 for 0<t< t/2