Presentation on the software radio course and platform by Dr. Kalle Ruttik

1. A!
“Software Radio” course
Special session
SNhANCE Study Tour
Kalle Ruttik
Department of Communications and Networking
School of Electrical Engineering
Aalto University

2. A! Content
 Course information
 Background, target group …
 Course structure
 Content of the course
 Gnu radio platform
 Research projects around the used platform
 Demo

3. A! History of the course
 ”Software radio” is a new laboratory works based course
that is introduced in fall 2013
 Current bachelor level laboratory works are build for
illustrating and validating the communication theory
 It repeats the content of “theory” courses
 New laboratory works course
 Strengthen students software skills
 Build a bridge between communication theory and
programming
 Show how to apply theory in practice

4. A!
Basic courses (70 op)
Aalto-studies + obligatory (10 op)
Program defines(60 op)
Major (60 op)
Program main course
Degree program
subject related
courses
Bachelor degree
(10 op)
Minor (25 op)
Elective (25 op)
Bachelor degree
• Basic studies (70 op)
- Aalto-courses + obligatory courses
- Courses definded by the program
• Major (60 op)
- Basic courses of the program
- Bachelor thesis (10 op)
• Minor (25 op)
- Minor subject courses offered by
schools of Aalto.
• Elective courses (25 op)
- Additonal course in major and
minor subject
- Strengthening minor (mobility)
- Short minor
4

5. A! Information theory (IT), major 60 cr
Elective studies, Special courses (25 cr)
Select 5 courses:
• Applied signal processing 5 cr (SA)
• Random processes in
telecommunications 5 cr (SA)
• Basics of Internet technology 5 cr
(TLV)
• Application programming 5 cr (TLV)
• Transmission methods 5 cr (TLV)
• Software radio (Ohjelmistoradio) 5 cr
(TLV)
• Bachelor thesis and seminar
10 op
• Basics of information theory,
5 cr (TLV+SA)
• Basics of automatics and
system analysis, 5 cr (AS)
• Information theory, 5cr (TLV)
• Digital signal processing and
filtering, 5 cr (SA)
• Modeling and analysis of
communication networks, 5
cr (TLV)
• Elective studies 25 op

6. A!
Elective courses 25 CR
•Basics of information theory, 5 cr (TLV)
•Information theory, 5cr (TLV)
•Digital signal processing and filtering, 5
cr (SA)
•Modeling and analysis of
communication networks, 5 cr (TLV)
•Signals and systems (TLV) 5 cr
•Applied signal processing 5 cr (SA)
•Random processes in telecommunication 5
cr (SA)
•Basics of Internet technology 5 cr (TLV)
•Application programming 5 cr (TLV)
•Transmission methods 5 cr (TLV)
•Software radio (Ohjelmistoradio) 5 cr (TLV)
Information theory (IT), minor 25 cr

7. A! Background information
 The course belongs into bachelor degree program of
Communication engineering
 Course combines theory and experiments
 About 50 -60 students per year
 Prerequisites
 “Signals and Systems”
 “Transmission methods”
 The laboratory works also explores and explains system
level issues not treated in any other bachelor level
course in our curriculum.

8. A!
The structure of the course

9. A! Educational aspects of laboratory works
 Learning outcomes specific to Laboratory works
 experimental skills
 real world experience
 experience for constructing actual systems
 discovering the results predicted by the theory
 familiarization with equipments
 motivation due to the clear practical results
 teamwork
 networking with outsides, searching information from different sources and contacts
 communication skills.
 Broader educational targets
 investigation of a phenomena
 practicing problem solving skills
 practicing inquiring about the phenomenas.

10. A! Observed problems with laboratory works
 Course organization related problems
 Students have different studying styles,
 strict instructions vs “playing around” with equipments
 Course assessment related problems
 Students drive to get “right answers”
 Too much freedom does not lead to good learning
 Need of feedback from “authority”
 Practical experiments implementation related issues
 The course too extensive, too much time spend on practical
measurements
 The equipments are not reliable
 Student groups may malfunction

11. A! Challenges
 Mismatch between the teacher intention and students
perception of the experimental work targets
 Students just measure and do not understand what is going on
 Provide experiments with open ended questions
 Students tend to follow only the measurement instructions
 Use wider set of assessment methods
 Not only assessments on measurement reports

12. A! Guidelines
 Plan inquiry type laboratory exercises
 Balance between the type of experiments
 Open ended questions
 Strict instructed measurements
 Balance between the work in small groups and larger
class based events

13. A! Structure of a lab work
 Preliminary exercises
 Student learn the background material
 First class
 Students plan the measurements
 Laboratory measurements
 Done in two person teams
 Measurements can be done during certain days, no strict time
limits
 Follow up class
 Analysis of the experiment results
 What was done, what can be concluded

14. A! Teaching objectives
 Transceiver related topic
 After this course, you know how a radio transceiver is constructed.
You understand how the practical receiver differs from the
theoretical models. You know how to model a non-ideal
transceiver and how to measure the errors produced by the non-
ideal behavior of the transceiver.
 Software project
 You understand the structure of a software project and you are
able to participate in a large software project with multiple
programmers. You know the basics of problem solving methods
and you are able to apply those methods in your own projects.
 Communication systems related issues
 You understand what the interference is. You can predict how the
interference impacts radio links and radio communication systems
in general.

15. A! Core content Complementary
knowledge
Specific
knowledge
Scientific
skills
Measurements: planning,
implementation and analyze.
Modeling of radio systems.
Modeling and analyzing of errors
Interference concept and
modeling.
Problem solving strategies.
Impact of radio
environment and
transceiver
implementation
errors on a design of
a radio system.
Professional
skills
Programming of radio
transceivers.
Software management with
version control systems.
Testing of software radios
Knowledge about
measurement
equipments use in
testing of radio
systems.
How large are the
errors in existing
systems.

16. A! Course structure
 The course contains four laboratory works and an
independent project. The laboratory works use software
radios that are implanted by using the universal software
radio platform (USRP) and GNU-radio framework.
 During the course, the students study the performance
of the software radio transceiver. They learn how the
radio performance is described and how it is measured.
 By using GNU-radio as an example, students learn how
to structure a software project, how to handle version
control and how to create and add new functions to the
software based transceiver chain.

17. A! Topics of the lab exercises
 Study of a transceiver chain
 Visualizing the theory taught on previous theory courses
 Tranceiver performance measurements
 Learning about non-ideal behavior of the
 Radio communication system measurements
 Interference and its impact
 Software project management
 Cooperation with other programmers and software version
control
 Learning problem solving methods
 Problem solving strategies and their use in small personal
project

18. A! Assessment method
 Assessment based on the reports per group
 2 person groups
 Preliminary exercises: 30 points
 Measurement plans: 20 points
 Measurement reports: 50 point

19. A! Students workload
Laboratory work Load
Introduction to a transceiver chain 25 h
Transceiver performance measurements 25 h
Interference in a radio environment 25 h
Implementing a function for a software radio 25 h
Independent project 33,5 h
One labwork Load
Preliminary exercises 10 h
Contact teaching 2 h
Measurements 3 h
Measurements reports 10 h

20. A! Workload
 Lectures/contact hrs 0 h
 Exercise/contact hrs 0 h
 Laboratory works hrs 40 h
 Independent study 90 h
 Examination 0 h

21. A! Teachers workload
In a week Total
Teacher 24 h 108 h
Assistent 21 h 84 h
Teacher
 Preliminary reports: 1x20 min total 30x20 10 h
 Measurement reports: 1x20 min total 30x20 10 h
 Lectures: 4x2 = 8 h
 Preparation for a lectures 4x2 = 8h
 Independet project: 2+4 h seminar time
Assistant
 Prearation for labworks: 4x3 = 12 h
 Measurements: 4 x 18 = 72 h

22. A! Content of individual labworks
 How the ”analog” equations are implemented in digital
computers
 Each laboratory work contains
 Communication theory
 Software radio implementation related issues
 Software radio development process

23. A! Topics of the lab exercises
 Study of a transceiver chain
 Visualizing the theory taught on previous theory courses
 Transceiver performance measurements
 Learning about non-ideal behavior of the
 Radio communication system measurements
 Interference and its impact
 Software project management
 Cooperation with other programmers and software version
control
 Learning problem solving methods
 Problem solving strategies and their use in small personal
project

24. A! Lab1: Transceiver chain
 Communication theory
 3dB bandwidth, signal power measurements, SNR estimation
 FM modulation
 OFDM transmission
 Students plan: AM and FM signal SNR measurements
 Software radio implementation
 Students will look and comment on implementation of software
radio blocks
 Code development process
 Read and comment on GNU radio development process
http://gnuradio.org/redmine/projects/gnuradio/wiki/TutorialsCor
eConcepts

25. A! Transceiver performance measurements
 Communication theory
 Signal constellation and Error Vector magnitude (EVM)
 SINR estimation by using EVM, SNR estimation from signal
power.
 BER measurements
 Student planned measurements: Transmitter linearity
estimation and measurements
 Software radio: adding and compiling a new block
 Gr-modtool: Students compile their own block
 Doxygen
 Using doxygen for documenting the code

26. A!
Radio communication system
measurements
 Communication theory
 Interference: co-channel, adjacent channel
 Channel coding gain
 Students planned measurements: Pathloss and attenuation in
the radio channel
 Software radio
 Students add functionality to a ready software radio block.
 Noise generation block: adds noise to the input signal
 Code development process
 Coding style quide
 http://gnuradio.org/redmine/projects/gnuradio/wiki/Coding_gui
de_impl

27. A! Software project management
 Communication theory
 Generation and using of CRC
 Software radio
 Test driven programming
 Code development process
 Using git version control system for managing the code

28. A! Learning problem solving methods
 Individual project where the students have to use the
learned skills
 Review of problem solving strategies
 Students have to document their problem solving process and
describe each step in the light of the problem solving strategies

29. Platform

30. A! Transceiver
Tx software
Running PC
USRP
Rx software
Running in PC
USRP
Air interfaceTransmitter Receiver

31. A! Our System

32. Software

33. A! Software with USRP
 Support software
 NI Labview
 http://www.ni.com/usrp/
 MathWorks
 http://www.mathworks.se/hardware-support/usrp.html
 GNU radio

34. A! GNU radio
 GNU radio is an open
source software
development kit
 Hierarchical structure
 High level blocks in
Python
 Signal processing in C++
 Primary a simulation tool.

35. A! Gnu radio
 Software radio
http://en.wikipedia.org/wiki/Software_radio
 Core concept of GNUradio
http://gnuradio.org/redmine/projects/gnuradio/wiki/Tutori
alsCoreConcepts
 Beginners guide
http://gnuradio.org/redmine/projects/gnuradio/wiki/HowT
oUse
 Tutorial of how to write a new block
http://gnuradio.org/redmine/projects/gnuradio/wiki/OutOf
TreeModules

36. A! Under active development
 Academic papers
from GNU radio
webpage
http://gnuradio.org/redm
ine/projects/gnuradio/
wiki/AcademicPapers

37. Hardware
USRP

38. A! Hardware

39. A! USRP

40. A! RF daughterboards
xcvr2450
 2.4-2.5 GHz and 4.9-5.9
GHz
 Half Duplex Only
 TX output power
 100 mW
 Single synthesizer
shared between Rx and
Tx
 RSSI measurement that
can be read from
software
SBX
 400 MHz to 4.4 GHz
 TX output power
 16 to 20 dBm,
 with 32dB of power
control range
 Dual synthesizers for
independent Tx and Rx
 NF
 < 3GHz: 5-7 dB
 3 – 4 GHz: 7 -10 dB
 4 – 4.4 GHz: 10 – 13 dB

41. A! Devices linearity
0 0.2 0.4 0.6 0.8 1
-80
-60
-40
-20
0
20
Input level
MeasuredOutputPower[dBm]
USRP2
N200
Ouput
im3
0 0.2 0.4 0.6 0.8 1
-80
-60
-40
-20
0
20
Input level
MeasuredOutputPower[dBm]
USRP2
N200
Ouput
im3

42. A! Linearity II input 0.1
USRP2 N200

43. A! USRP related research
 Radio transmission in TV white/black space
 Y. Beyene “TV Black-space Spectrum Access for Wireless Local Area
and Cellular Networks”, master thesis, Aalto.
 Performance study of overlay transmission on TV signal
Y. Beyenne, K. Ruttik, R. Jäntti, “Effect of Secondary transmission on
Primary Pilot Carriers in Overlay Cognitive Radios”, submitted to
CrowCom 2013.
 H. Tewodros, “Testing a Simple Algorithm for LTE Synchronization
and Cell Search”, master thesis, Aalto.
 Study of the impact of delay on overlay transmission
• Synchronization schemes for cognitive BS
K.G. Vishnu, “Network Time Synchronization in Time Division - LTE
systems”, diploma thesis Feb.2013.
• Implementation of the time synchronization in TDD network
• MIMO transmission in USRP platform
G.C. Moreno, “Communication over USRP by using multiple antennas”

44. Thanks