PDF Slides of my thesis research. The gr-bertool is a handy and useful software to evaluate the BER of the digital modulation both in the wired and wireless channel.

1. `
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Universita di Messina - Facolta di Ingegneria
Emulation of a Radio Link by means of Software Radio
Supervisors
Candidate
Prof. Salvatore Serrano
Arturo Rinaldi
Prof. Giuseppe Campobello
Master’s Degree in Electronics Engineering - Academic Year 2010/11
Messina, November 10th 2011

2. Goal of the thesis work
The making of a learning tool for the analisys of the digital modulations
in different communication channels
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

3. Goal of the thesis work
The making of a learning tool for the analisys of the digital modulations
in different communication channels
The simulated channels were :
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

4. Goal of the thesis work
The making of a learning tool for the analisys of the digital modulations
in different communication channels
The simulated channels were :
Wired : AWGN
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

5. Goal of the thesis work
The making of a learning tool for the analisys of the digital modulations
in different communication channels
The simulated channels were :
Wired : AWGN
Wireless : Rayleigh and Rician
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

6. Goal of the thesis work
The making of a learning tool for the analisys of the digital modulations
in different communication channels
The simulated channels were :
Wired : AWGN
Wireless : Rayleigh and Rician
Verify the correspondence between the theoretical and experimental
results of the BER (Bit Error Rate)
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

7. Goal of the thesis work
The making of a learning tool for the analisys of the digital modulations
in different communication channels
The simulated channels were :
Wired : AWGN
Wireless : Rayleigh and Rician
Verify the correspondence between the theoretical and experimental
results of the BER (Bit Error Rate)
Provide complementary tools to show how audio and video files are
modified under the effect of the transmission channels
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

8. Goal of the thesis work
The making of a learning tool for the analisys of the digital modulations
in different communication channels
The simulated channels were :
Wired : AWGN
Wireless : Rayleigh and Rician
Verify the correspondence between the theoretical and experimental
results of the BER (Bit Error Rate)
Provide complementary tools to show how audio and video files are
modified under the effect of the transmission channels
The gr-bertool was built by using the open-source DSP platform GNU
Radio
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

9. GNU Radio
GNU Radio is an open-source software
toolkit providing a huge library of
blocks for Digital Signal Processing
(DSP) written in C++ which can be
combined together in order to build and
develop radio applications
Gnu Radio Companion (GRC), XML
Python Flow Graph
(Created using the processing blocks)
SWIG (Port C++ blocks to Python)
GNU Radio Signal Processing Blocks
(C++)
USB Interface / Gigabit Ethernet
Generic RF Front End
( USRP / USRP 2 )
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

10. GNU Radio
GNU Radio is an open-source software
toolkit providing a huge library of
blocks for Digital Signal Processing
(DSP) written in C++ which can be
combined together in order to build and
develop radio applications
It is provided with a graphical interface
to ease its learning curve (GRC : GNU
Radio Companion)
Gnu Radio Companion (GRC), XML
Python Flow Graph
(Created using the processing blocks)
SWIG (Port C++ blocks to Python)
GNU Radio Signal Processing Blocks
(C++)
USB Interface / Gigabit Ethernet
Generic RF Front End
( USRP / USRP 2 )
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

11. Software-Defined Radio : an introduction
GNU Radio was developed to be in use of Software-Defined Radio
(SDR), a new “paradigm” of communication systems
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12. Software-Defined Radio : an introduction
GNU Radio was developed to be in use of Software-Defined Radio
(SDR), a new “paradigm” of communication systems
A receiver is an SDR device if its communication functions are made as
reconfigurable software working on ad hoc hardware
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

13. Software-Defined Radio : an introduction
GNU Radio was developed to be in use of Software-Defined Radio
(SDR), a new “paradigm” of communication systems
A receiver is an SDR device if its communication functions are made as
reconfigurable software working on ad hoc hardware
So it’s possible to implement different software transmission standards
by using only one device
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

14. Software-Defined Radio : an introduction
GNU Radio was developed to be in use of Software-Defined Radio
(SDR), a new “paradigm” of communication systems
A receiver is an SDR device if its communication functions are made as
reconfigurable software working on ad hoc hardware
So it’s possible to implement different software transmission standards
by using only one device
An SDR sytem is also able to recognize and avoid possible interferences
with other transmission channels
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15. The developed tool : gr-bertool
The tool main GUI
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16. The developed tool : gr-bertool
BER experimental verification
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17. The developed tool : gr-bertool
Real-Time BER experimental verification
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18. The developed tool : gr-bertool
Complementary tools
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19. BER experimental verification
The Bit Error Rate (BER) of a digital modulation, is the number of bit
errors divided by the total number of transferred bits during a studied
time interval
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

20. BER experimental verification
The Bit Error Rate (BER) of a digital modulation, is the number of bit
errors divided by the total number of transferred bits during a studied
time interval
Let’s verify the BER theoretical values with the experimental ones by
varying the signal-to-noise ratio Eb /N0
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

21. BER experimental verification
The Bit Error Rate (BER) of a digital modulation, is the number of bit
errors divided by the total number of transferred bits during a studied
time interval
Let’s verify the BER theoretical values with the experimental ones by
varying the signal-to-noise ratio Eb /N0
From digital communications theory is well known that for a Q-PSK
modulation the Bit Error Rate is given by :
Pb = Q
2Eb
N0
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

22. BER experimental verification
This set of tools calculates the BER in
a range of Eb /N0 values given by min
and max with the opportunity to
choose the increase step size
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23. BER experimental verification
This set of tools calculates the BER in
a range of Eb /N0 values given by min
and max with the opportunity to
choose the increase step size
We can enable or disable the Gray
Coding
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

24. BER experimental verification
This set of tools calculates the BER in
a range of Eb /N0 values given by min
and max with the opportunity to
choose the increase step size
We can enable or disable the Gray
Coding
By clicking on the Plot button the BER
curves are showed in a simple BER vs
Eb /N0 diagram
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25. BER experimental verification
We can see a perfect agreement between the theoretical results and the
experimental ones :
(a) BER AWGN BPSK
(b) BER AWGN Q-PSK
(c) BER AWGN 8-PSK
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26. Real-Time BER and signal constellation evolution
This tool allow us to show the real-time
BER and signal constellation evolution
in the three different types of
examinated transmission channels
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

27. Real-Time BER and signal constellation evolution
This tool allow us to show the real-time
BER and signal constellation evolution
in the three different types of
examinated transmission channels
In the following example we’ll show the
BER evolution in the Rician Channel in
the range of Eb /N0 values going from
−15 dB to 0 dB
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

28. Real-Time BER and signal constellation evolution
This tool allow us to show the real-time
BER and signal constellation evolution
in the three different types of
examinated transmission channels
In the following example we’ll show the
BER evolution in the Rician Channel in
the range of Eb /N0 values going from
−15 dB to 0 dB
Once started the BER value settles to
the BER value corresponding to
Eb /N0 = 0 dB about equal to ≈ 0.11
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

29. Real-Time BER and signal constellation evolution
This tool allow us to show the real-time
BER and signal constellation evolution
in the three different types of
examinated transmission channels
In the following example we’ll show the
BER evolution in the Rician Channel in
the range of Eb /N0 values going from
−15 dB to 0 dB
Once started the BER value settles to
the BER value corresponding to
Eb /N0 = 0 dB about equal to ≈ 0.11
Ch1 Experimental Value ; Ch2
Theoretical Value
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

30. Real-Time BER and signal constellation evolution
This tool allow us to show the real-time
BER and signal constellation evolution
in the three different types of
examinated transmission channels
In the following example we’ll show the
BER evolution in the Rician Channel in
the range of Eb /N0 values going from
−15 dB to 0 dB
Once started the BER value settles to
the BER value corresponding to
Eb /N0 = 0 dB about equal to ≈ 0.11
Ch1 Experimental Value ; Ch2
Theoretical Value
Let’s see the evolution....
Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio
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31. Real-Time BER evolution
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32. Real-Time BER evolution
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33. Real-Time BER evolution
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34. Real-Time BER evolution
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35. Real-Time BER evolution
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36. Real-Time BER evolution
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37. The signal constellation
Let’s consider a generic transmission scheme for a TLC system.
m(t)
S
s(t)
Tx
r(t)
Tx Channel
d(t)
Rx
D
Figure : Generic block diagram for a TLC system
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38. The signal constellation
Let’s consider a generic transmission scheme for a TLC system.
m(t)
S
s(t)
r(t)
Tx
d(t)
Rx
Tx Channel
D
Figure : Generic block diagram for a TLC system
In the absence fo any noise in the channel the generci transmitted
symbol si will be correctly received. The plot of the received symbols is
¯
knows as “Constellation” of the digital modulation.
ℑ
s3 (‘01’)
¯
s0 (‘11’)
¯
ℜ
s2 (‘00’)
¯
s1 (‘10’)
¯
Figure : Constellation of a QPSK modulation
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39. The signal constellation
The presence of noise in the channel modifies phase and amplitude of
the transmitted symbols and so the received symbol ri is not one
¯
belonging to the constellation showed before
ℑ
s3 (‘01’)
¯
s0 (‘11’)
¯
The transmitted si symbol is not
¯
correctly received
ri
¯
ℜ
s2 (‘00’)
¯
s1 (‘10’)
¯
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40. Evolution of the Signal Constellation
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41. Evolution of the Signal Constellation
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42. Evolution of the Signal Constellation
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

43. Evolution of the Signal Constellation
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

44. Evolution of the Signal Constellation
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

45. Image Transmission
This tool allow us to observe how the
most common image formats are
affected by digital modulations
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

46. Image Transmission
This tool allow us to observe how the
most common image formats are
affected by digital modulations
We studied the effects over the
simulated channels (AWGN, Rayleigh e
Rician) for a fixed value of
Eb /N0 = 0 dB and Q-PSK digital
modulation for a Jpeg image
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

47. Image Transmission
This tool allow us to observe how the
most common image formats are
affected by digital modulations
We studied the effects over the
simulated channels (AWGN, Rayleigh e
Rician) for a fixed value of
Eb /N0 = 0 dB and Q-PSK digital
modulation for a Jpeg image
Let’s see the results......
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

48. Image Transmission : AWGN Channel
(a) Original
(b) AWGN
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

49. Image Transmission : Rician Channel
(c) Original
(d) Rician
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

50. Image Transmission : Rayleigh Channel
(e) Original
(f) Rayleigh
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

51. Audio Transmission
This tool allow us to observe how the
most common audio formats are
affected by digital modulations
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

52. Audio Transmission
This tool allow us to observe how the
most common audio formats are
affected by digital modulations
We studied the effects over the
simulated channels (AWGN, Rayleigh e
Rician) for a fixed value of
Eb /N0 = 10 dB and Q-PSK digital
modulation
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

53. Audio Transmission
This tool allow us to observe how the
most common audio formats are
affected by digital modulations
We studied the effects over the
simulated channels (AWGN, Rayleigh e
Rician) for a fixed value of
Eb /N0 = 10 dB and Q-PSK digital
modulation
We took as sample the wav file
play it sam.wav with the following
specifications :
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

54. Audio Transmission
Specifications of the sample file
play_it_sam.wav :
File Size: 1.76M
Bit Rate: 1.41M
Encoding: Signed PCM
Channels: 2 @ 16-bit
Samplerate: 44100Hz
Replaygain: off
Duration: 00:00:10.00
Let’s see the results....
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55. Audio Transmission
(g) Originale
(h) Canale AWGN
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56. Audio Transmission
(i) Rician
(j) Rayleigh
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57. Conclusions
Why using gr-bertool ? Advantages
It’s an helpful tool for the teacher to use in TLC courses
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

58. Conclusions
Why using gr-bertool ? Advantages
It’s an helpful tool for the teacher to use in TLC courses
The student can find a quick verification with the learnt notions during
classes
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

59. Conclusions
Why using gr-bertool ? Advantages
It’s an helpful tool for the teacher to use in TLC courses
The student can find a quick verification with the learnt notions during
classes
It has an ”user-friendly” GUI
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

60. Conclusions
Why using gr-bertool ? Advantages
It’s an helpful tool for the teacher to use in TLC courses
The student can find a quick verification with the learnt notions during
classes
It has an ”user-friendly” GUI
It’s open-source !
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

61. Conclusions
Future Developments
Addition of other components for transmission by using the USRP
(through USB) and USRP2 (through Gigabit Ethernet) boards to study
the real-time signals evolution
(k) USRP1
(l) USRP2
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Arturo Rinaldi - Emulation of a Radio Link by means of Software Radio

62. Conclusions
Future Developments
Addition of other components for transmission by using the USRP
(through USB) and USRP2 (through Gigabit Ethernet) boards to study
the real-time signals evolution
(m) USRP1
(n) USRP2
Implementation of other modules for the network protocols (i.e.
802.11n, Bluetooth) always for learning goal
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63. Contact Information
Arturo Rinaldi
Freelance Collaborator @ DIECII
Address : Dep. of Electronics Engineering (DIECII) - C.da di Dio, 98166 Messina (Italy)
E-mail : arty.net2@gmail.com
Fixed : +39-090-3977376 ; Mobile : +39-340-5795584 (Whatsapp)
Skype : arty.net ; Facebook : arty.net
Twitter : artynet2 ; LinkedIn : Arturo Rinaldi
Prof. Giuseppe Campobello, Ph.D.
Researcher in Telecommunications
Address : Dep. of Electronics Engineering (DIECII) - C.da di Dio, 98166 Messina (Italy)
E-mail : gcampobello@unime.it
Fixed : +39-090-3977378
Prof. Salvatore Serrano, Ph.D.
Researcher in Telecommunications
Address : Dep. of Electronics Engineering (DIECII) - C.da di Dio, 98166 Messina (Italy)
E-mail : sserrano@unime.it
Fixed : +39-090-3977522
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