Signals and systemsSignals and systems Faculty of Electronics, Telecommunications and Information...

1

1

Signals and systems

Faculty of Electronics, Telecommunications and Information

Technologies

Communications Department

http://shannon.etc.upt.ro/teaching/ss-pi

All universities from Romania want to be among

the 500 top universities

2

QS ranking for year

2019: https://www.topuniversities.com/universit

y-rankings/world-university-

rankings/2019

This is just one ranking …

2

3

UPT in QS /

2019

4

An important factor

in ranking is the

number of scientific

papers and their

impact (number of

citations)!

3

5

https://scholar.google.ro/citations?user=BbMzjt8AAAAJ Citations in Google Scholar

database

Citations in ISI database

6

https://publons.com/researcher/2697802/corina-nafornita/

https://publons.com/institution/386897/

4

7 7

Our curricula

follows the one

established by

the best

teacher of

signal

processing

http://www.rle.mit.edu/people/directory/alan-oppenheim/

As you can see the course is nearly identical to the one at Timisoara

8

https://ocw.mit.edu/resources/res-6-007-signals-and-systems-spring-2011/

5

9 9

The recitations are similar,

But the lab works are only done by

simulations

10 10

As you can see there is a lot of theory in the course

6

11 11

There are two important quizzes with many

restrictions…

12 12

The final exam is similar to

ours

7

13 13

Students have to present reports for the

lab, to be submitted to the teaching

assistant …

14 14

Same course

at Stanford

8

15 15

16 16

The course at EPFL Lausanne

https://people.epfl.ch/martin.vetterli?lang=en

9

17 17

http://lcav.epfl.ch/Martin_Vetterli/books

The book is free to download.

18 18

University of Toronto course

http://www.comm.utoronto.ca/~dkundur/course/signals-and-systems/

10

19 19

University of Toronto

http://www.comm.utoronto.ca/~dkundur/course/ece-362-digital-signal-processing/

20 20

Useful Java Applets.

11

21

Cost reduction has favoured equipping cars with radar

sensors to prevent accidents.

But this involves signal processing of advanced level

and solving estimation and detection problems.

22

Car with radar sensors of 24GHz & 77 GHz

12

23

Architecture of frequency-modulated continuous wave (FMCW)

radar. Two antennas are used: transmit and receive. The received

signal is multiplied by the emitted signal, obtaining signals with

beat frequencies given by the Doppler effect (corresponding to

each target). After sampling and A/D conversion, frequency

analysis is performed, using the FFT algorithm.

24

Commonly used FMCW signals are chirp like. The

instantaneous frequency varies linearly in time

(increasing or decreasing)

Time representation of

chirp signal Instantaneous frequency of

chirp signals

13

25

We can use rapid chirp of duration up to 100 microsec. The beat

frequency is

2v 2 2SW SWB

CPI CPI

B R B Rf

cT cT

2R 2v 2vexp 2 ; m=0, 1, ... ,M-1

c cch ch chy mT a mT j mT

exp 2 Tx t a t j f t

If the emitted signal is

then the received signal is

26

A double frequency analysis, using the FFT algorithm, leads to the

estimation of the range R and velocity, v of the target

14

27

Speed (m/s)

Range (

mete

rs)

Range-Speed Response Pattern

-200 -100 0 100 2000

20

40

60

80

100

120

140

160

180

200

Pow

er

(dB

)

-110

-100

-90

-80

-70

-60

-50

-40

-30

-20

Here is an example with 9 detected targets at different ranges

having different velocities

28

COURSE OBJECTIVES

This course is found in electrical and computer engineering curricula, the concepts and techniques that form the core of the subject are of fundamental importance in all engineering disciplines.

Our approach has been guided by the continuing developments in technologies for signal and system design and implementation, which made it increasingly important for a student to have equal familiarity with techniques suitable for analyzing and synthesizing both continuous-time and discrete-time systems.

Significant emphasis will be placed both

on time domain analysis of systems through the operation of convolution

and

on frequency domain analysis of systems using the Fourier transforms.

15

29

COURSE TOPICS

1-Introduction.

2-Convolution.

3-Spectral Analysis for Analog Periodic

Signals (Fourier series)

4-The Continuous-Time Fourier Transform

5-Fourier Analysis of Discrete-time Signals

30

TEXTBOOKS/REFERENCES

1. Corina Nafornita, Signals and Systems, vol. 1, 2009, & Corina Nafornita

and Alexandru Isar, Signals and Systems, vol. 2, ed. Politehnica, 2016,

Table of contents

http://shannon.etc.upt.ro/teaching/ss-pi/Signals_Systems_TOC.pdf

http://shannon.etc.upt.ro/teaching/ss-pi/Signals_Systems2_TOC.pdf

2. Alan V. Oppenheim, Alan S. Willsky with S. Hamid Nawab, Signals &

Systems, Second Edition, Prentice Hall, Upper Saddle River, New Jersey,

1997.

3. Simon Haykin, Barry Van Veen, Signals and Systems, 2nd edition, John

Wiley & Sons, 2003

16

• Exam weight in final mark: 2/3

• Activity weight in final mark

(lab+recitations): 1/3

• Teaching materials can be found here: http://shannon.etc.upt.ro/teaching/ss-pi/ or on intranet

• Please bring our own tables printed on

paper for all activities (including exam). http://shannon.etc.upt.ro/teaching/sp-pi/Tables/Tables-

transforms.pdf

31