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Lecture 2

-(chapter 2)

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Main Contents

Important types of signals and their operat

Linear and shift-invariant system

Easier to analyze and implement

The convolution and difference equation re

Representations and implementation of sigsystems using MATLAB

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Discrete-Time Signals

Analog and discrete signals Analog signal

trepresents any physical quantity, time in

Discrete signal: discrete-time signal

N is integer valued, represents discrete in

)(txa

)(nx

In Matlab, a finite-duration sequence represerequires two vectors, and each for xand n.

Example:

,,,L ==

}7,3,4,1,0,1,1,2{)( =nx

];7,3,4,1,0,1,1,2[

];4,3,2,1,0,1,2,3[

=

=

x

n

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Discrete Sequences

Finite-duration sequences:

Unit sample sequences:

0121

0

0 ,,

0

,1)( nnnnnn

nn

nnnn

==

}),1(),0(),1(,{)}({)( LL xxxnxnx ==

Unit step sequences:

0121

0

0

0 ,,,0

,1)( nnnnnn

nn

nnnnu