Scilab/Scicos toolboxes for Telecommunications Sebastien

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Scilab/Scicos toolboxes for Telecommunications Se
bastien Mons, Alan Layec, Abderrazak. Benadji,
Tibault Reveyrand, Raphael Sommet, Edouard Ngoya,
Raymond Quéré.   XLIM/C2S2 Université de
Limoges, 123 av. A. Thomas, 87060 Limoges,
France INRIA Domaine de Voluceau-Rocquencourt,
B.P. 105, 78153 Le Chesnay Cedex, France e-mail
sebastien.mons_at_xlim.fr
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• Outline
• XLIM Laboratory
• C2S2 department
• Scilab/scicos environment, why this choice ?
• Toolboxes developed
• Advanced Device simulation
• Advanced Circuit-system simulation
• Measurement test set-ups

Conclusion Information to prepare a Phd at our
laboratory
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XLIM Laboratory
Limoges (FST)
Limoges (ESTER)
Brive (IUT)
5 Research Departments
Department of Mathematics and Informatics (DMI)
Synthesis of Realistic Images, formal
calculation, modeling, dynamical optimization,
arithmetic, code, cryptography Waves and
associated systems (OSA) Multifunction
Antennas. WirelessNetworks, Waves and Health
Electromagnetic compatibility, Ultra-Wideband
Impulse Devices. MIcro-NAnotechnologies for
Optoelectronical Components and
Microwaves Multifunction Antennas, MEMS and
Ceramic Components, Optoelectronic, organic
Micro-Nanotechnologies. Modeling Tools.
Photonic (PHOTONIC) New Generations of Optical
fibers, Architectures of Optical and Lasers
Amplifiers, Interferometric and Biophotonic
Instrumentations, High-speed Optoelectronic.
Components Circuits - Signals and Systems
High Frequencies (C2S2) Telecommunications
Systems, Power amplifiers, Oscillators fréquency
generation, Low-noise functions, Advanced
Simulation, Advanced Instrumentation
XLIM
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• Platform of Technologie and Instrumentation
  (PLATINOM)
• Transverse Programs
• Security and reliability of the Information
  systems
• TeraHertz
• Radar and Optics Imaging
• Human Resources
• 174 professors, researchers, post doctorands
• 156 PhD students, 34 students
• Scientific Production (2002-2004)
• 94 thesis 75 articles and invited
  communications
• 17 contribution to works 296 international
  Communications (with proceedings)
• 175 international reviews 188 national reviews
  and communications
• 14 patents

Components, circuits, antennas Set-ups
(Telecommunication - radar systems) Technologies
for Optical fibers and micro-nanosystems
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C2S2 Department Chips Circuits - Signals and
Systems High Frequencies
Manager Raymond Quéré Contact
raymond.quere_at_xlim.fr Human resources 30
professors, researchers 42 PhD students, 7
masters degree students 6 Research Projets
Telecommunications Systems micro-optoelectronic
components, Architectures, links Simulation
Low-noise functions integrated adaptive
filtering Design methodologies Recieved
integrated systems Technologies (GaAs, Silicium,
SiGe)
Power amplifiers Smart power Architectures
Design Modeling (nonlinear, Thermique, ) new
technological process (GaN, InP, )
Oscillators fréquency generation Architectures
Conception Modeling (NL,Noise,) Chips (GaAs,
SiGe, InP,) Instrumentation
PLATINOM
Advanced Instrumentation
Advanced Simulation
Bottom Up Analysis
Top Down Design
AmCAD Engineering
MITIC Common Laboratory Thales/XLIM
Xpedion Design Systems Agilent Technologies
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RF front-end simulation problematic compromise
accuracy / time consuming
Top-down process
System architecture
synthesis
Device architecture
dimensioning
Hamonic Balance, Time Envelope
Data-flow analysis
Bottom-up analysis
Top-down process use of accurate simulation
tools to decrease margins taken on components
specifications Bottom-up analysis
behavior-modeling predict and analyse the impact
of microwave components on system performance
Cost reduction is a key issue for the development
of the next generation of suchs systems
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System complexity ? Hierarchic decomposition
Sub-system
Physic Thermal Mechanical Electro-magnetic Electri
cal
Take into account of different physics-based
aspects ?
chip
Linked to measurements setup ?
function
Circuit
System level
Cope with different kinds of formalisms and
simulators ?
circuit level
Component
component level
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• Scilab/Scicos environment
• Why this choice?
• Available tools do not fully correspond to our
  needs
• Scilab/scicos provide a powerful open computing
  environment for scientific applications
• Solution Integration of a number of tools in
  the high level Scilab/Scicos environment
• Advantages
• Offers free and powerful numerical computation
  capabilities
• An open and extensible computing environment
  (C, C, Fortran...)
• High and low level graphical subroutines for
  post-processing
• Many available various "toolboxes"
• Powerful linear algebra libraries such UMFPACK,
  ATLAS, ARPACK, TAUCS...
• Easy to interface existing simulators
• Possibility to perform parallel tasks (PVM,...)

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Organisation of Research tools
Key points Allow mixed simulation (event,
discrete and continuous) Models adopted for
analog parts keep the notion of
signal/information physics based variables
(power, energy, currents, voltages,temperature) Co
simulation systems/circuits/devices Very large
system simulation multi channel
systems Computation of low Bit Error Rates
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1 Advanced device-circuit simulation
1.2 HBT/Circuit Simulation (R. SOMMET,Z. RIAH)

• Direct coupling between
• Physics-based simulation (HBT)
• Circuit Simulation
• Reduced thermal model
• Noise simulation capabilities

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1.2 PIN diode Simulation (thesis E. Gatard)

• A physics-based simulation of
• the diode impedance
• Based on the Ambipolar equation
• Recombination in the heavy doped
• region are taken into account

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1.3 Model Order Reduction of thermal problem
FEM (ANSYS)
System of n ODEs
( 100000)
MOR (SCILAB)
Reduced System of r ltltn ODEs
(lt 30)
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2 Advanced circuit-system simulation
2.1 - MODNUM for the modeling / simulation of
communication systems (Alan
Layec thesis)
Analog circuits (PA, LNA, antennas,
filters) Digital circuits (source, channel
coders/decoders) Mixed circuits (Digital
converters, modulators, local oscillators)
Communication chain
Scilab/Scicos is used for interaction between
analog circuit and pure digital circuits
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Contents
Modnum is
71 scicos blocks Scicos Diagram, Scilab
scripts linux / windows platform Documentation
(pdf/html)
Base -band PSK/QAM modulations Blocks Schematics
in-line functions Spread-spectrum Components
Pseudo Noise sequence generators (Quasi-Chaotic,
PN, Gold sequence ) Miscellaneous scopes for
Scicos 3D trajectory, Eye Diagram, Scattered
Diagram Frequency synthesizer
components Phase/Frequency Detector, VCO, Delta-Si
gma modulators,... Chaotic systems schematics
Chua's, Rössler's, Van Der Pol's systems, .
Toolbox organization
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Simulation in batch mode Simulations with
PVM
BER at 10-7 (at least 100 errors) For 1 processor
(2GHz) 300 h of computation !!! Ideas to reduce
the time computation of BER break the long
sequence use several CPU to realize the
simulation Scilab interfaced function of Parallel
Virtual Machine System enables communication
between distant session.
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Screenshots
Chaotic sub-system
PSK chain transmission
Synthesizer
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2.2 Circuit-system interaction cosimulation /
macro-models implementation (Abderrezak
Bennadji thesis)
Cosimulation direct communication between
circuit and system simulators
?
High level of precision CPU time
?

• Behavior models
• reduced image integrating the circuit simulation
  concepts
• dynamic of the circuit (memory,)
• Interactions between circuits (mismatches)
• able to run indifferently with TE/ HB solvers

?
Good level of precision CPU time
?
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Behavior modeling principle
simulations
Black-box representation
?
?

x(t)
y(t)
X(t)
Complex Topology
characterizations
Objectives Take into account Inter-stages
mismatches, Nonlinear memory effects
Models developped for PAs

• Volterra Model
• Nonlinear Impulse Response Model
• Modulated Volterra Model

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Modeling principle Two data processing modules
Data extraction
Characterization Procedure
C language
Module 1
Simulations
Data processing
header file
Calculation of the filters coefficients
.dat
.head
Measurements
Header file
.head
Module 2
Re
Re
Execution of the model in Scicos
Im
Scicos block
Im
yf0(u0, u1, u2, )
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Circuit/System coupling Method cosimulation
principle
To improve modeling accuracy a
Co-simulation interface
At every activation of the block, the following
tasks are achieved

• Launching the circuit simulator for the
  execution of the envelope simulation, this
  simulation can contain several steps of analysis.
• To return the simulation results to the system
  simulator.

System simulator (Scicos)
Amplifier
Circuit Simulator (GoldenGate )
Amplifier
IPC Interface
OL
Bidirectional Communication
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Applications models vs circuit simulation
AM /AM AM/PM Model
Volterra Model
Impulse response Model
Co-simulation
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Simulation 16 QAM LNA BiCMOS L Band ACPR Curve _at_
5 MB/S
60
50
ACPR (dB)
40
30
20
-22
-18
-14
-10
-6
-2
0
Pin (
dBm
)
Pin (
dBm
)
Co-simulation
Volterra Model
AM/AM AM/PM Model
Impulse response
Complete chain simulation time
2 min. 23 sec
14 sec
2 min. 18 sec
1h. 12 min
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3 Measurement test set-ups
Use of the GPIB toolbox
Easy to modify, no compilation needed, possible
link with scicos simulator
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Example Two test setups fully automated with
scilab
Time domain envelop test setup (modulated
signals )
Frequency domain test setup

• Specific instruments
• arbitrary waveform Generator,
• sampling digital oscilloscope
• characteristics
•  1 GHz - 4 GHz
• Modulated band pass 125 MHz
• Power 10W RF
• Interests
• Memory effect characterization
• Measurement basis for system modeling
• Study of linearisation techniques
• validation of PAs models.

• Specific instruments
• Pulsed generator, VNA, automated Tuner,
• actives loops, scopes, probe station.
• characteristics
•  1 GHz - 26,5  GHz
• Multiharmonics
• Power 10W RF
• Modes CW , pulsed CW and 2 tones
• Interests
• Transistor characterization, PAE, Pout IM3,,
• validation of transistors models
• automatic search of optimal loading impedance

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Conclusion

• Faster and more accurate system level simulations
  chain is more and more important in modern system
  design.
• AESA-Radar,
• Telecommunication
• Laboratory strategy federate different tools
  within a system level hierarchic design framework
• Scilab/Scicos is an efficient tool for high
  frequency device, circuit and system simulation.
• 2/3 toolboxes presented are open-source, freely
  usable

Support
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Useful addresses the university of Limoges
welcomes you
University of Limoges http//www.unilim.fr
Reception Office of the international students
(BAEI)
To answer your questions about

• Lodging
• Administrative formalities
• Transportation
• Opening a bank account
• The student health plan
• Discovering Limoges and its region

Phone [phone] Mail
accueil.international_at_unilim.fr
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to integrate the university course
http//www.sciences.unilim.fr/
to prepare a master of Research STIC
(Communication and Information Sciences and
Technologies )

• Mathematics, Cryptography, coding,
  calculation thierry.berger_at_unilim.fr
• Data Processing, Information Sciences and
  Communication plemenos_at_unilim.fr
• Circuits, Systems, Micro and Nanotechnologies
  for the communications high frequencies and
  optics vaudon_at_ircom.unilim.fr

. more information on http//www.sciences.unilim.
fr/edsts

• Formation, master of Research, course of
  Language, thesis, laboratory, useful links

• Join our laboratory to prepare a thesis
• Subjects of thesis (26 suggested for the year
  2006)
• Fellowship scheme 
• Presentation of the departments of Research
• Contacts

http//www.xlim.fr