Lecture One
Thursday, September 3, 2015
9:45 AM
EC 401 is like learning a language
Systems  The ECE products, devices, computers, communication media, etc that interacts with its
surroundings or
Ex. An iPhone is the system, the
Signals  the conceptualiz
EC401 HW9 (Spring 2016)
Due Wednesday Apr 6, 2016
HW9.1
Let ! " be a discretetime signal with DTFT # $ %& . Assume that '( ) is the continuoustime
associate of ! " and that *( +, is the CTFT of '( ) . For ! " given in each part of this
problem sketc
EC401 Lab6 (Spring 2016)
Due Wednesday Mar 23, 2016
Lab 6.1
On the EC401 Spring 2016 Blackboard site you will find the MATLAB file EC401Lab6.m.
This MATLAB file is the skeleton of the laboratory assignment that requires you to perform
blurring (via conv
EC401 HW6 (Spring 2016)
Due Wednesday Mar 16, 2016
HW6.1
Find the Fourier Series Representation of each of the following signals. Sketch !" s as a function
of #.
(a) $ % = '(%
)
(b) $ % = ./'
0)
(c) $ % = 1
4
(d) $ % =
*
%+
1
)
,
%+
)
*
,5 6, 7
8
HW6
EC401 Lab3 (Spring 2016)
Due Wednesday Feb 10, 2016
Lab 3.1
On the EC401 Spring 2016 Blackboard site you will find the MATLAB file EC401Lab3.m.
This MATLAB file is the skeleton of the laboratory assignment that requires you to use the
MATLAB function st
Lecture Four
Tuesday, September 15, 2015
9:58 AM
Recipe  simpler signal operations on ingredients to make more complicated signals
xe = x(t) + x(t)
2
xo = x(t)  x(t)
2
Discretetime signals
x[n]; x only takes integer values
graph x[n]
Example:
unit im
Lecture Three
Thursday, September 10, 2015
10:02 AM
Area of unit impulse is 1
Basic Operations on Signals
delay: x(t  t0)
 delayed by t0
advanced: x(t + t0)
 advanced by t0
flip: x(t)
 flips x(t) about t = 0 (time reversal)
amplitude scaling: cx(t)

Lecture Two
Tuesday, September 8, 2015
9:57 AM
Examples of Signals:
1. x(t) = 2
"dc signal"
x(t) = 2cos(0t)
x(t) = 2e^j0t, complex exponential signal = 2cos(0t) + 2jsin(0t)
2. x(t) =
"unit step", "switch"
Sometimes u(t)
not g(t)
For now, the value at