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Seminar SCEE
Optimization of MultiOptimization of Multi--standards standards
Software Defined Radio Software Defined Radio
Equipments : Equipments :
A Common Operators’ ApproachA Common Operators’ Approach
SUPELEC - Campus de RennesSCEE – Signal, Communications et Electronique Embarq uée
IETR – UMR CNRS 6164Institut d'Electronique et Télécommunications de Re nnes
Sufi Tabassum GUL29th October, 2009
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 2IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Presentation outline
� Multi-standard Design Issue
� Parametrisation Techniques for Software Radio
� Graph Modeling of SDR Equipment
� Optimization of Graph Models
� Case Studies of Common Operators
� Conclusions & Perspectives
� Publications
2
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 3IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Plan de la présentation
� Problème de la Conception Multi-standard� Techniques de Paramétrisation pour la Radio Logicie lle
1. Technique par Fonctions Communes2. Technique par Opérateurs Communs
o Approche Pragmatiqueo Approche Théorique
� Modélisation Graphique des Equipments de Radio Logi cielle� Modèles Théoriques de Graphes pour les Equipments Multi-standards
de Radio Logicielle� Optimisation de Modèles de Graphes
� Paramètres de Coûto Types de Coûtso Fonction de Coût
� Optimisationo Recherche Exhaustiveo Recuit Simuléo Algorithmes Génétiques
� Cas d'Etudes d'Opérateurs Communs� DMFFT� LFSR� FRMFB
� Conclusions & Perspectives� Publications
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 4IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Presentation outline
� Multi-standard Design Issue� Parametrisation Techniques for Software Radio
1. Common Function Technique2. Common Operators’ Technique
o Pragmatic Approacho Theoretical Approach
� Graph Modeling of SDR Equipment� Graph Theoretical Models of Multi-standards SDR Equipments
� Optimization of Graph Models� Cost Parameters
o Types of Costso Cost Function
� Optimizationo Exhaustive Searcho Simulated Annealingo Genetic Algorithms
� Case Studies of Common Operators� DMFFT� LFSR� FRMFB
� Conclusions & Perspectives� Publications
3
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 5IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Presentation outline
� Multi-standard Design Issue� Parametrisation Techniques for Software Radio
1. Common Function Technique2. Common Operators’ Technique
o Pragmatic Approacho Theoretical Approach
� Graph Modeling of SDR Equipment� Graph Theoretical Models of Multi-standards SDR Equipments
� Optimization of Graph Models� Cost Parameters
o Types of Costso Cost Function
� Optimizationo Exhaustive Searcho Simulated Annealingo Genetic Algorithms
� Case Studies of Common Operators� DMFFT� LFSR� FRMFB
� Conclusions & Perspectives� Publications
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 6IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Multi-standard SDR design
GPS
Bluetooth
Figure 1 : Multi-standards SDR design
4
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 7IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Multi-standard SDR Design
Velcro Solution
SDR Approach
Our Approach
Set of Reconfigurable
Common Operators
Approach x
Figure 2 : Multi-standards design trends
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 8IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Multi-standard SDR Design
� To design multi-standard reconfigurable radio, we h ave choice between two extremes
� One extreme: go “Velcro” (Efficient but costly)
o One self-contained module per standard.
� Other extreme: go “Primitive” (Cheaper but deadlines!)
o Use only adders, multipliers, etc.
o Provide “higher” functionality by multiple calls of simpler modules.
� There may be other choices
� Intermediate granularity (e.g. in NoC, SoC etc.)
� Formalization at an intermediate granularity
� Our aim is to find the best trade-off between:
� “ Performance and Cost ”
5
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 9IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Presentation outline
� Multi-standard Design Issue� Parametrisation Techniques for Software Radio
1. Common Function Technique2. Common Operators’ Technique
o Pragmatic Approacho Theoretical Approach
� Graph Modeling of SDR Equipment� Graph Theoretical Models of Multi-standards SDR Equipments
� Optimization of Graph Models� Cost Parameters
o Types of Costso Cost Function
� Optimizationo Exhaustive Searcho Simulated Annealingo Genetic Algorithms
� Case Studies of Common Operators� DMFFT� LFSR� FRMFB
� Conclusions & Perspectives� Publications
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 10IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Parametrisation
� Techniques of parameterization were introduced in order to
� Identify commonalities
� Exploit these commonalities
� Parameterization can be considered as a sub-part of the digi tal
radio design methodology.
� We propose
� “Parameterization technique should be considered as a method that searches
for and finds all the commonalities inside single/between several different
standards in order to optimize, the resources during equipment’s
implementation and/or execution phases.”
6
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 11IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Parametrisation Techniques for SDR
� Parametrisation :
� A promising technique of designing radio systems entities
� Takes advantages of the programmable or at least reconfigurable
capabilities
���� An optimal sharing between hardware and software
resources.
� Parametrisation Techniques can be divided into :
1. Common Function Technique
2. Common Operators’ Technique
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 12IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Common Function Technique
� CF technique : function sharing among different
standards [1].
� Non-duplication of redundant components &
� Possible save in complexity.
Figure 3 : Multi-standards transmitter data processing tasks
[1]. W. H. W. Tuttlebee, Software Defined Radio: Enabling Technologies. John Wiley & Sons Ltd. UK, 2002.Details about chapter 8 to be added
7
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 13IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Common Function Technique
� Some conclusions about CF : As stated in [2], CF is not
sufficient because
� CF technique depends highly upon the selected standards.
� The evolution to new standards must require the addition of the distinct
components of each function in the associated CF.
� As a consequence, the CF should be redefined and redesigned to be
capable to meet the requirements of the advanced standards.
� Due to standards’ dependency, our feeling is that the CF
technique is not flexible enough for SDR applications.[2]. Arnd Rhemiere
Details to be added
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 14IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Common Operator Technique
� Common operator technique : identification of common
elements based on structural aspects.
� CO Performs operations without knowing their application.
� CO is independent of implementation of a terminal.
� CO is to be considered as an Open Technique[3].
� CO can be called and re-called by distinct functions several
times all along the terminal.
[3]. L. Alaus, J. Palicot, C. Roland, Y. Louët, and D. Noguet, “Promising Technique of Parametrisation ForReconfigurable Radio, the Common Operators Technique: Fundamentals and Examples,” SpringerScience + Business Media LLC, 2009
8
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 15IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Common Operator Technique
Figure 4 : Generalized block diagram showing the breakdown of several standards
Very Fine Grain
Velcro
Incr
easi
ng G
ranu
larit
y
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 16IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Common Operator Technique
� The goal is to find the maximum number of common elements
and then share their functionalities between several
processing tasks.
� In order to attain the best cost-performance trade-off
� Identify some level of granularity
���� CO technique consists in increasing the granularity of the
basic primitive levels elements to address in an SDR.
9
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 17IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Common Operator Technique
� A trade-off could be proposed between CF and CO, with the
following rules:
1. A CF can call (one or several) functions,
2. A CF can use (one or several) operators,
3. A CO cannot call a function.
Figure 5 : Two technique of parametrisation (trade-offs)
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 18IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Common Operator’ Technique
� Common Operators’ can be identified either by :
1. Pragmatic approach (PA) or
o The initial approach developed to identify or create possible COsand follows two stages:
– Existing Search &– Constructive Search
2. Theoretical approach (TA)
o An attempt to formalize SDR design.
o It consists in moving the classical breaking down of Figure.4 intoa graphical approach.
o Applies optimization process in order to find the most relevantCOs (or their combination) present in the graph derived.
o The optimisation process related to the TA is performed by aspecific cost function to be minimized.
10
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 19IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
The Theoretical Approach
� Our vision of the parameterization:
“The parameterization techniques are the means to find the
optimal path in the tree derived from Figure 2. Here we are
considering a global optimality”
� Three challenges arise:
1. The definition of the graph
2. The definition of cost parameters, finding costs and
development of the cost function
3. The optimization algorithms
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 20IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Candidates for Common Operator
� A common operator is a tuneable operator which can carry out
some common functions of several standards.
� FFT/Butterfly[3], DMFFT[4] and LFSR[5] are strong candidates for
common operators as they can be used in the implementation of
numerous important tasks of a communication transceiver, e.g. filtering,
equalization, channelization, OFDM (de)modulation, convolutional
coding, scrambling, etc.
[3]. J. Palicot, C. Roland, “FFT: a Basic Function for a Reconfigurable Receiver,” ICT’03 Conference, Thaiti,France, 2003.
[4]. Ali Al Ghouwayel, Yves Lou¨et and Jacques Palicot, “A Reconfigurable Butterfly Architecture for Fourier andFermat Transforms,” IEEE WSR’2006, Karlsrhue, Germany, March 2006.
[5]. L. Alaus, D. Noguet and J. Palicot, “A Reconfigurable Linear Feedback Shift Register Operator for SoftwareDefined Radio Terminal,” ISWPC, Santorini, Greece, May 2008.
11
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 21IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Presentation outline
� Multi-standard Design Issue� Parametrisation Techniques for Software Radio
1. Common Function Technique2. Common Operators’ Technique
o Pragmatic Approacho Theoretical Approach
� Graph Modeling of SDR Equipment� Graph Theoretical Models of Multi-standards SDR Equipments
� Optimization of Graph Models� Cost Parameters
o Types of Costso Cost Function
� Optimizationo Exhaustive Searcho Simulated Annealingo Genetic Algorithms
� Case Studies of Common Operators� DMFFT� LFSR� FRMFB
� Conclusions & Perspectives� Publications
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 22IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
� We Model radio as graph :
� Progressively simpler processing elements (PE).
� When necessary, a PE is called multiple times (not
replicated).
� 2 critical parameters per PE:
o cost andtime(computational delay)
Graph Modeling
12
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 23IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Overview of Our Methodology
� Our objective is to find commonalities and hence
Common Operators
� We want to optimize graphs of multi-standard
systems based on these Common Operators
� Our procedure consists of three steps:
1. Drawing graphs of a radio system
2. Assigning cost parameters to various blocks of radio system
3. Running optimization algorithms to find the optimum solution
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 24IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Graph Modeling
Left: PE A needs:Either B OR C
Right: PE A needs:BothB AND C
� “ Hypergraph” in order to introduce two different types ofdependencies between the nodes:
� OR dependency
� AND dependency
Figure 7 : A hypergraph of tri-standard SDR systemFigure 6 : Two Possible Dependencies in Graph
13
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 25IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Graph Modeling
NAND NOT XOR AND OR
WiFi #1 WiFi #2 WiFi #3 WiMAX
Scrambler/Randomiser
Convolutional Coder Interleaver
Constellation Mapper FFT-N
RS Encoder
Butterfly
Adder MultiplierLFSR
LUTa a’ b b’
Very Fine Grain
Velcro
Incr
easi
ng G
ranu
larit
y
Figure 8 : A simplified hypergraph of tri-standard SDR system
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 26IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Presentation outline
� Multi-standard Design Issue� Parametrisation Techniques for Software Radio
1. Common Function Technique2. Common Operators’ Technique
o Pragmatic Approacho Theoretical Approach
� Graph Modeling of SDR Equipment� Graph Theoretical Models of Multi-standards SDR Equipments
� Optimization of Graph Models� Cost Parameters
o Types of Costso Cost Function
� Optimizationo Exhaustive Searcho Simulated Annealingo Genetic Algorithms
� Case Studies of Common Operators� DMFFT� LFSR� FRMFB
� Conclusions & Perspectives� Publications
14
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 27IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Cost Parameters
� Parameters associated with PE 1. Building Cost (BC) &
o The cost of the block/PE capable of computing a function, called building cost(BC) and it is paid once during the useful life of a radio.
2. Computational Cost (CC)o The computing time required to perform a particular function, called
computational cost (CC) and it is paid every time a component is brought intoplay.
� Parameters associated with arcs1. Number of Calls (NoC)
o TheNoC parameter specifies thenumber of times a lower level PE is called toperform the functionality of higher level PE.
� In order to solve the optimization problem that findsbalance between economy and computing efficiency weconsider these parameters in our cost/objectivefunction.
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 28IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Types of Costs
� We have considered 3 types of costs for PEs
� Cost#1: In terms of equations
o Number of multiplications and/or additions, generic cost.
� Cost#2: FPGA/ASIC implementation
o In terms of gates/LUT/Slice/hardware synthesis (HW)
� Cost#3: DSP(SW)/HW execution time
o In terms of number of cycles/Time of execution
� These costs are based on:
� Design objectives and may be design phase (in terms of
equations : at early design phase for instance)
� Implementation figures availability
� Required precision
Sometimes BCSometimes CC
Obviously BC
Obviously CC
Sometimes BCSometimes CC
15
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 29IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Cost Function
denotes the building cost of ith component in the system.
indicates if the ith node is present in the system or not.
is the total building cost of all the components that are present in the SDR system.
}{ Nn ,...,2,1=
indicates that there may be n standards present in an SDR where
i.e. if we choose N=3 then it means that there are three
321 ,,, SandSSstandards present namely in an SDR system.
denotes the computational cost of kth component in the system.
nS
}{ Nn ,...,2,1=
is the total computational cost of any of , where
.
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 30IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Cost Function
nS }{ Nn ,...,2,1=is the total computational cost of all of , where
.
+= ∑∑∑ ∈∈ n k
Nnnkni
iiSbool
SDR SCCwNBCwCNnn
))((..min_
))((
Provide a balance between relative costs of BC and CCω
ωn
� Coarse grain oriented design� Towards Velcro
� Fine grain oriented design� Towards primitive level
If ω << ωn
If ω >> ωn
where
16
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 31IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Presentation outline
� Multi-standard Design Issue� Parametrisation Techniques for Software Radio
1. Common Function Technique2. Common Operators’ Technique
o Pragmatic Approacho Theoretical Approach
� Graph Modeling of SDR Equipment� Graph Theoretical Models of Multi-standards SDR Equipments
� Optimization of Graph Models� Cost Parameters
o Types of Costso Cost Function
� Optimizationo Exhaustive Searcho Simulated Annealingo Genetic Algorithms
� Case Studies of Common Operators� DMFFT� LFSR� FRMFB
� Conclusions & Perspectives� Publications
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 32IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Optimization Techniques
� Techniques that give exact optimal solution� Exhaustive Search� Require a computing effort that increases exponentially with
number of nodes.
� Techniques that provide near-optimal solution in lesscomputing� Simulated Annealing� Genetic Algorithms
17
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 33IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Exhaustive Search
� Exact methods require a high computing effort (increasesexponentially with number of nodes).
� Only for problems involving fewer nodes (say 10 nodes).
� Used to check if sub-optimal methods find a good solution (fo rsimple cases).
Figure 9 : A generic view of SDR equipment Figure 10 : Results of running ES on generic example
200200
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 34IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Simulated Annealing
� Simulated Annealing : gives a near-optimal solution
� A random-search technique.
� Exploits an analogy of metal cooling into a minimum energy
crystalline structure .
Figure 11 : Results of running SA on generic example
Optimization tendency
18
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 35IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Genetic Algorithms
� Genetic Algorithms (GA) are a family of computational model sinspired by evolution.
� An implementation of a GA begins with a population of (typica llyrandom) chromosomes. Over successive generations, thepopulation evolves toward an optimal solution.
Figure 12 : Results of running GA on generic example
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 36IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Comparison on generic example
Figure 13 : Results of running GA on generic example
19
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 37IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Sum-up
1. Use graph to list each possible design.
2. For each design, calculate its total cost: i.e. BC and CC
(time to perform each top PE).
3. Use Algorithms e.g. exhaustive search, simulated
annealing, etc. to optimize design (finds the lowest cost
solution).
4. Choose least expensive design that performs the
functionality of each top PE.
5. After exploring various optimization techniques we came
to the conclusion that SA is best suited to the problem at
hand.
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 38IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Presentation outline
� Multi-standard Design Issue� Parametrisation Techniques for Software Radio
1. Common Function Technique2. Common Operators’ Technique
o Pragmatic Approacho Theoretical Approach
� Graph Modeling of SDR Equipment� Graph Theoretical Models of Multi-standards SDR Equipments
� Optimization of Graph Models� Cost Parameters
o Types of costso Cost Function
� Optimizationo Exhaustive Searcho Simulated Annealingo Genetic Algorithms
� Case Studies of Common Operators� DMFFT� LFSR� FRMFB
� Conclusions & Perspectives� Publications
20
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 39IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Sub-design examples
� Goal: validate our approach
Means: integrating the results of other PhD student s of
research team
� Also permits to mature our approach
� Confront to reality: the theoretical approach
� DMFFT: In collaboration with Ali Al-GHOUWAYEL
� LFSR: In collaboration with Laurent ALAUS
� FRMFB: In collaboration with R. MAHESH
� A GUI was developed to facilitate these case studies
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 40IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Figure 14 : Graphical user interface
GUI Tool
� In order to facilitate the drawing of graphs and associatingcosts for different costs parameters a GUI was developed.
Figure 15 : Parameters’ management window
21
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 41IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Example #1: DMFFT
DMFFT : Dual mode FFT Context of an OFDM demodulation with RS
decoding
Figure 16 : An example of FFT sharing between OFDM demodulation and RS decoding over GF(Ft).
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 42IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Example #1: DMFFT
Figure 17 : A simplified tri-standard SDR system
22
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 43IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Example #1: DMFFT
Best solution ���� implement FFT through DMFFT and RBPECO ���� RBPE
BC/CC
=128
FFT-N
1
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 44IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Example #2: LFSR
A linear feedback shift register (LFSR) is ashift register whose input bit is a linear functionof its previous state.
There are two implementation styles of LSFRs:Fibonacci RF-LFSR and Galois RG-LFSR.
The study of common operators has lead us tobuild the architectures called R-LFSR and ER-LFSR respectively.
23
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 45IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Example #1: DMFFT
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 46IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Example #2: LFSR
x-LFSR
22ER 8R14ER 2R 6RG
x-LFSR
WiFi
24
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 47IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Example #2: LFSR
22ER 8R14ER 2R 6RG
x-LFSR
WiFi
Best solution ����
CO ����
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 48IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Example #3: Channelizers
Best solution ����
FRMFBCO ���� FRMFB
Figure 16 :
25
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 49IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Example #3: Channelizers
OFDM Modulation/
Demodulation
FFT
Figure 16 :
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 50IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Example #3: Channelizers
Best solution ���� Implement RS decoding and Channelization through DMFFT and RBPE
CO ���� RBPE
Figure 16 :
26
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 51IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Conclusion on use cases
� Graphs
� Modeling air interface standards as graphs
� Cost parameters and costs
� Optimization techniques
� local optimal vs global optimal� Confirm results found in other studies without the
graphical approach (these are usually local optimum s)� Here can be mixed/merged with others to find global
optimums.
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 52IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Presentation outline
� Multi-standard Design Issue� Parametrisation Techniques for Software Radio
1. Common Function Technique2. Common Operators’ Technique
o Pragmatic Approacho Theoretical Approach
� Graph Modeling of SDR Equipment� Graph Theoretical Models of Multi-standards SDR Equipments
� Optimization of Graph Models� Cost Parameters
o Types of costso Cost Function
� Optimizationo Exhaustive Searcho Simulated Annealingo Genetic Algorithms
� Case Studies of Common Operators� DMFFT� LFSR� FRMFB
� Conclusions & Perspectives� Publications
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Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 53IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Conclusions
� Ever increasing demands of users, manufactures and service
providers : Focus has been shifted toward SR approach.
� Optimization aspects of flexible radio system design : redu cing
the cost, complexity and size of the radio terminals/base-
stations
� We presented various case studies to validate our approach.
� We also elaborated how our approach can be used to find the
global optimal solution.
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 54IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Perspectives
1. Scheduling issue
2. Investigation regarding other optimization algorithms e. g. GA
etc.
� Two new PhDs are starting to address 1 & 2.
3. More and more complete graphs
� More and more standards
� PHY layer was addressed
� Aim is to draw graph from application to PHY layer including
intermediate layers to exploit cross layer optimization aspects
4. Exploration of other techniques to formulate cost function .
5. Detailed study of costs for mixed designs consisting of FPGA ,
DSP etc.
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Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 55IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Perspectives
6. Find new COs
7. Provide an industrial tool for designers of future SDR and CRequipments’
� That allows to optimize multi-standards SDR design &
� That provides a choice to orientate the design towards high
granularity or low granularity
� It is certainly interesting to follow the research directio nsmentioned above to further enhance the proposed ideas.
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 56IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Publications
� International Journal Papers1. S. T. Gul , Ali Al-Ghouwayel, C. Moy and Y. Louët, “A Novel Design of Reconfigurable Fourier Transform
Operator Over CC and GF(GF(FFtt)) for Future Multi-standards SDR Equipments,” International Journal ofCommunication Networks and Distributed Systems-IJCNDS, Accepted in June 2009 for publication by the end of2009.
2. S. T. Gul , L. Alaus, C. Moy, J. Palicot and D. Noguet, “Optimal set of LFSR Common Operators for Multi-Standards Cognitive Radio Terminals,” International Journal of Autonomous and Adaptive Communications-IJAACS, Special Issue on Cognitive Radio Systems, Accepted in July 2009 for publication in 2010.
3. S. T. Gul , R. Mahesh, C. Moy, J. Palicot and A. P. Vinod “Filter Bank Techniques for SDR Channelizers andtheir Optimization using Graph Theoretical Approach,” EURASIP Journal on Advances in Signal Processing,Special Issue on Filter Banks for Next Generation Multicarrier Wireless Communications, Submitted, June, 2009.
� International Conference Papers1. S. T. Gul , C. Moy and J. Palicot, “Graphical Modeling and Optimization of Air Interface Standards for
Software Defined Radios,” 12th IEEE International Multitopic Conference-INMIC2008, Karachi, Pakistan, pp.473-479, December 2008.
2. S. T. Gul , R. Mahesh, C. Moy, A. P. Vinod and J. Palicot, “A Graphical Approach for the Optimization of SDRChannelizers,” International Union of Radio Science (Union Radio Scientifique Internationale-URSI); XXIXGeneral Assembly, Chicago, Illinois, USA, August 2008.
3. S. T. Gul , C. Moy and J. Palicot, “Two scenarios of flexible multi-standard architecture designs using amulti-granularity exploration,” The 18th Annual IEEE International Symposium on Personal, Indoor and MobileRadio Communication- PIMRC’07, Athens, Greece, pp. 1-5, September 2007.
� International Conference Workshops1. S. T. Gul , L. Alaus, D. Noguet, C. Moy and J. Palicot “The Common Operator Technique: An Optimization
Process to Identify and Design a Set of Common Operators to Perform SDR Equipment (projectNEWCOM++),” Dynamic Spectrum Management in Cognitive Radio Networks, ICT-MobileSummit 2009,Santander, Spain, June 2009.
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Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 57IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Thanks for your attention
Questions?
Sufi Tabassum GUL- SUPELEC – 29th
Oct. 2009 58IETR - INSTITUT D’ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATI ONS DE RENNES
Relative Weights of BC & CC