# Chapter2 - CHAPTER 2: CHAPTER DISCRETE-TIME SIGNALS &amp;...

This preview shows pages 1–18. Sign up to view the full content.

CHAPTER 2: CHAPTER 2: DISCRETE DISCRETE - - Lesson #4: DT signals Lesson #5: DT systems Lesson #6: DT convolution Lesson #7: Difference equation models Lesson #8: Block diagram for DT LTI systems Duration: 9 hrs

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Lecture #4 Lecture #4 DT signals DT signals 1. Representations of DT signals 2. Some elementary DT signals 3. Simple manipulations of DT signals 4. Characteristics of DT signals
Converting a CT signal into a DT signal by sampling : given x a (t) to be a CT signal, x a (nT) is the value of x a (t) at t = nT b DT signal is defined only for n an integer < < = = n ), n ( x ) nT ( x ) t ( x a nT t a -2T -T 0 T 2T 3T 4T 5T 6T 7T . . . nT t Sampled signals Sampled signals

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
n e -1 0 1 2 3 4 e x[n] e 0 0 1 4 1 0 e 1. Functional representation = = = n , 0 2 n , 4 3 , 1 n , 1 ] n [ x Representations of DT signals Representations of DT signals 2. Tabular representation
3. Sequence representation Representations of DT signals Representations of DT signals { } 1 , 4 , 1 , 0 ] [ = n x -1 0 1 2 3 4 5 n 4. Graphical representation 4 1 1

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Lecture #4 Lecture #4 DT signals DT signals 1. Representations of DT signals 2. Some elementary DT signals 3. Simple manipulations of DT signals 4. Classification of DT signals
1. Unit step sequence 2. Unit impulse signal 3. Sinusoidal signal 4. Exponential signal Some elementary DT signals Some elementary DT signals

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
1 0 [ ] 0 0 n u n n , = , < Unit step Unit step -1 0 1 2 3 4 5 6 n 1 1 1
Time Time - - shifted unit step shifted unit step < = 0 0 0 n n , 0 n n , 1 ] n n [ u 0 -n 0 -1 n 0 n 0 +1 n For n 0 > 0 1 1 1

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Time Time - - shifted unit step shifted unit step < = 0 0 0 n n , 0 n n , 1 ] n n [ u -n 0 -1 n 0 n 0 +1 0 n For n 0 < 0 1 1 1
Unit impulse Unit impulse 1 0 [ ] 0 0 n n n δ , = = , -2 -1 0 1 2 n 1

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document