Line 9: Line 9:
 
3. The Fourier coefficients <math>\,a_1\,</math> and <math>\,a_3\,</math> are equal.
 
3. The Fourier coefficients <math>\,a_1\,</math> and <math>\,a_3\,</math> are equal.
  
4. The value of the signal at <math>\,n=0\,</math> is zero.
+
4. <math>\,a_1\,</math> is maximal while <math>\,a_2\,</math> is non-negative.
  
5. Bleck!?
+
5. The value of the signal at <math>\,n=0\,</math> is zero.
 +
 
 +
 
 +
== Answer ==

Revision as of 20:02, 25 September 2008

Guess the Periodic Signal Question

Suppose a DT singal satisfies the following properties:

1. x[n] is periodic with period 4 and has Fourier coefficients $ \,a_k\, $.

2. $ \,\sum_{n=0}^{3}x[n]=4\, $

3. The Fourier coefficients $ \,a_1\, $ and $ \,a_3\, $ are equal.

4. $ \,a_1\, $ is maximal while $ \,a_2\, $ is non-negative.

5. The value of the signal at $ \,n=0\, $ is zero.


Answer

Alumni Liaison

Prof. Math. Ohio State and Associate Dean
Outstanding Alumnus Purdue Math 2008

Jeff McNeal