chap1 Introduction chap2 Discrete-Time Signals and Systems.ppt

Outline of Chap1~2
Chapter 1
Introduction
Under what condition can DSP course be given to undergraduate students?
What the author has done in this book?
Why signals should be processed?
How signals are being processed?---
Analog Signal Processing vs.
Digital Signal Processing
Comparison of DSP over ASP
-Advantages
Developed Using Software puter;
Working Extremely Stable;
Easily Modified in Real Time ;
Low Cost and Portable;
-Disdvantages
Lower Speed and Lower Frequency
The two categories of DSP Tasks
(1) Signal Analysis:
Given: Input and System, Seeking Output(In Time and/or Frequency Domain)
(2) Signal Filtering
Given: Input and Output, Seeking System(Designing Filter)
Problems in MATLAB Programming
1. Left and Right Devision:
A\B = inv(A)*B; B/A = b*inv(A)
2. Array Operation (Dot Operation)
.* ./ .\ .^ .’
3. Polynomials and Their Roots
R=roots([a1,a2,…,an,an+1])
4. Residues of rational polynomial
r(1) r(2) r(3) r(4)
Y(s)= ---------- + ---------- + ----------- + ---------
s - p(1) s - p(2) s - p(3) s - p(4)
y(t) = r(1)*exp(p(1)*t) + r(2)*exp(p(2)*t) + r(3)*exp(p(3)*t) + r(4)*exp(p(4)*t)
[r,p,h]=residue(b,a)
y=r.’*exp(p*t)
Chapter 2 Discrete-Time Signals and Systems
Discrete-Time Signals: Typical Types of Sequences
Unit Sample Sequence δ(n)
Unit Step Sequence u(n)
Real plex Valued Exponential Sequence
Random Sequence
Periodical Sequence
Example of Forming periodical Sequence Using MATLAB
x=[3,4,5,6,7]; N=4; % method 1
x1=x’*ones(1,N)
x2 = x1( : );
xp = x2’;
np2=1:N*length(x); % method 2
xp2=x(mod(np2,length(x))+1;
stem(xp), stem(np2,xp2); % plot
Examples
Ex020100 – composite basic sequences
Ex020200 – operation on sequences
Ex020300 – complex sequence generation
Ex020400 – even-odd position
Operations on Sequences
Signal Addition*
Signal Multiplication (Modulation)
Signal Scaling*
Signal Shifting*
Sample folding
Sample Products
Signal Energy
Even and Odd Synthesis
Correlations of Sequences