(New page: ==Define a CT, LTI System== One possible CT, LTI system would be <math>y(t) = 3x(t-2) \!</math> ===Unit Impulse Response=== The unit impulse response of the system is found by substitu...)
 
(Signal Response)
 
(One intermediate revision by the same user not shown)
Line 21: Line 21:
 
Using the sifting property, we can easily find that our system function is defined as
 
Using the sifting property, we can easily find that our system function is defined as
  
<math>H(j\omega)=e^{-2j\omega}</math>
+
<math>H(j\omega)=e^{-2j\omega} \!</math>
  
 
==Signal Response==
 
==Signal Response==
Line 27: Line 27:
 
Now we need to find the LTI system above's response to my signal from section 4.1.  The response can be found with the equation
 
Now we need to find the LTI system above's response to my signal from section 4.1.  The response can be found with the equation
  
<math>y(t) = H(j\omega)x(t)</math>
+
<math>y(t) = H(j\omega)x(t) \!</math>
  
 
Using my signal from section 4.1
 
Using my signal from section 4.1

Latest revision as of 16:09, 26 September 2008

Define a CT, LTI System

One possible CT, LTI system would be

$ y(t) = 3x(t-2) \! $

Unit Impulse Response

The unit impulse response of the system is found by substituting $ \delta(t) $ for $ x(t) $. So, for the system

$ y(t) = 3x(t-2) \! $

$ h(t) = 3\delta(t-2) \! $

System Function

The system function is defined as

$ H(j\omega)=\int_{-\infty}^\infty h(\tau)e^{-j\omega\tau}d\tau $

Using the sifting property, we can easily find that our system function is defined as

$ H(j\omega)=e^{-2j\omega} \! $

Signal Response

Now we need to find the LTI system above's response to my signal from section 4.1. The response can be found with the equation

$ y(t) = H(j\omega)x(t) \! $

Using my signal from section 4.1

$ x(t) = 3cos(2t) = \frac{3}{2}e^{j2t}+\frac{3}{2}e^{-j2t} $

we can multiply each term by $ H(j\omega) $ to get

$ y(t) = e^{-j4}(\frac{3}{2}e^{j2t}) + e^{j4}(\frac{3}{2}e^{-j2t}) $

Simplifying this gives us

$ y(t) = \frac{3}{2}e^{j2(t-2)} + \frac{3}{2}e^{-j2(t-2)} \! $

Alumni Liaison

Sees the importance of signal filtering in medical imaging

Dhruv Lamba, BSEE2010