Skip to content Skip to navigation   You are here: Home »
Content » Fourier Series Approximation of a Square Wave
Recently Viewed  This feature requires Javascript to be enabled.
Fourier Series Approximation of a Square Wave  Module by: Don
Johnson. E-mail the author  Summary: Shows how to use Fourier
series to approximate a square wave, as opposed to the
sinusoidal waves seen previously.  The Fourier series
representation of a signal, as expressed for a square wave by
st= a 0 + k =1 a k cos2πktT+ k =1 b k sin2πktT s t a 0 k 1 a k 2
k t T k 1 b k 2 k t T says that the left and right sides are
"equal". We need to investigate equality through an example.
Example 1  Figure 1: Fourier series approximation to sqt sq t .
The number of terms in the Fourier sum is indicated in each
plot, and the square wave is shown as a dashed line over two
periods. Fourier series approximation of a square wave Fourier
series approximation of a square wave (fourier4.png)  Let's find
the spectrum of the square wave sqt sq t . Th