ELEC6831
Concordia University
Digital Communications
Question 1: (For this problem, you may use the provided formula sheet.)
A stream of digital data with data rate of 20 Mb/s is to be transmitted in an additive white
Gaussian noise channel with single si
ELEC6831
Assignment #1
Question 1.1: Binary Amplitude Shift Keying (radar)
A stream of 0s and 1s with bit rate of Rb = 1 / Tb is to be transmitted over an additive
white Gaussian noise channel with power spectral density N 0 watts per Hertz. These 0s
and
Instructions for Examination
ELEC6831/ELEC462
This is a closed book exam.
Standard type calculator can be used.
You may use the formula sheet which is attached.
Cellular phones are not allowed.
Show all the intermediate steps of your solution.
Make reason
Concordia University
ELEC462-ELEC6831
Digital Communications
Question 1:
A stream of digital data with data rate of 20 Mb/s is to be transmitted. This data is mapped to one
of sixteen symbols using a Gray coded 16-ary modulation scheme and communicated ov
ELEC 462/6831
Concordia University
Digital Communications
Instructions for Examination
This is a closed book exam.
Standard type calculator can be used.
You may use the formula sheet which is attached.
Cellular phones are not allowed.
Questions have equal
ELEC6831
Assignment #2
Due Time: Wednesday Feb. 26 at 4PM
Instructions:
Study problems all the problem sets which are posted in the Suggested Problem section of
the course web site.
There are 5 questions to be answered.
Assignment should be either dropped
CHAPTER 6
Channel Coding:
Part 1
Information
source
I
From other
sources
Message
symbols
,.,
Channel
symbols
~
Pulse
'"[
Bit
Synch
ronization
Digital
oU1put
Digital
baseband
waveform
c
h '"
Digital
bandpass
h
Channel n
"
impulse
response
waveform
Detect
1
ELEC 6831
Concordia University
Digital Transmission Systems
Instructions for Examination
This is a closed book exam.
Standard type calculator can be used.
You may use the formula sheet which is attached.
Cellular phones are not allowed.
Questions will be
Sunday Oct-22-2006 Midterm
Question #1
Given:
16 Signal Points
M 16 24 k 4 bits
Equiprobable
p S1 p S2 L p S16
1
16
2
AWGN Channel Probability Density Function @ 0, N 0 2 0, 0 0
N0
2
A Obtain the Symbol Error Rate (SER) as a function of the Average
ELEC 6831
Concordia University
Digital Communications I
Instructions for Examination
This is a closed book exam.
Standard type calculator can be used.
You may use the formula sheet which is attached.
Cellular phones are not allowed.
Questions have equal w
Chapter 5
Optimum Receivers for the Additive
White Gaussian Noise Channel
Table of Contents
5.1 Optimum Receiver for Signals Corrupted by
Additive White Noise
5.1.1
5.1.2
5.1.3
5.1.4
5.1.5
Correlation Demodulator
Matched-Filter Demodulator
The Optimum Det
ELEC462/6831
Concordia University
Winter 2011
Midterm Content
Feb. 18, 20:30 22:30, Room # to be announced
Material from the text book by SKLAR:
Chapter 3:
Whole chapter is included except section 3.4.
Chapter 4:
Whole chapter is included except material
Monday Oct-23-2006 Midterm
Question #1
Given:
8-Ary Modulation M 8 23 k 3 bits
p S1 p S2 L p S8
Equally Likely
AWGN Channel
0, N 0 2
1
8
A Obtain the Symbol Error Rate (SER) as a function of the Average Energy (EAV) using Union Bound +
Draw Decision
Random bits
Generator
AWGN
output bits
Fig: BPSK uncoded modulation system
In BPSK uncoded modulation system at first random bits are generated and after modulation the data is
passed through the rectangular pulse shaping filter. After being filtered addi
The Wireless Channel
Nitin Vaidya
(Chapter 2 of Course Notes)
2009
1
Terminology / Notation
Bandwidth
Power content
Power spectral density
Energy content
Decibel notation
2
Fourier Transform
If X(f) is fourier transform of x(t) then
X(f) : Frequency-doma
ELEC 462/6831: Digital Communications
Winter 2013
Final Exam
Instructor: Dr. Walaa Hamouda
This is a closed book exam
ONLY a formula sheet ONE 8.5x11 double-sided is allowed
-Graduate students:
do all problems
Undergraduate students: do problems 1 to 5 an
Assignment 3 Solution
1
Problem 1
1. The Gram-Schmidt procedure for the sequence S0 (t), S1 (t), S2 (t), and S3 (t) can be applied as follows:
The energy for each signal can be obtained as given by (1) to (4).
ES0
ES1
=
ES3
=
ES2
=
=
2Ts /3
|S0 (t)|2 dt
Assignment 2 Solution
1
Problem 1
1. Dene x(t) as the overall impulse response for the pulse shaping lter p(t), the channel c(t), and the matched
lter h(t) = p(Tb t), therefore x(t) = p(t)c(t)h(t), where () denotes convolution. Since we have an AWGN
chann
Assignment 1 Solution
1
Problem 1
1. The general autocorrelation for the process B(t) can be obtained as given by (1) where denotes the expectation operator. We have used the fact that A(t) and are statistically independent. Since A(t) is known to
be a WS
ELEC 6831
Assignment 4
Due Time: November 27 at 16:00
Instructions:
There are 4 questions to be answered. The first two questions consider receiver
synchronization. The last two questions are related to channel coding.
This is an individual assignment. In
ELEC 6831
Assignment 3
Due Time: November 11 at 16:00
Instructions:
There are 4 questions to be answered. Two of them are related to signal space
representation. The other two are related to higher order modulation and error analysis.
This is an individua