outage probability of cooperative communication

8/7/2019 Outage Probability of Cooperative Communication

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Outage Probability of cooperative communicationsOutage Probability of cooperative communicationsin Decodein Decode--andand--Forward Relaying with MultiForward Relaying with Multi--UsersUsers

Source Over Rayleigh Fading ChannelsSource Over Rayleigh Fading Channels

PresentedPresented by:by:

El AMRAOUIEl AMRAOUI TariqTariq

HILMIHILMI RedaReda

KABBASSIKABBASSI FadlFadl AllahAllah

MABROUKMABROUK HoudaHouda

2010/2011


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Introduction

Conclusion

Cooperative communications

Communication model

Outage probability

Perspectives

Outline

I

II

III

IV

V

VI


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INTRODUCTION

3


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Why cooperative communications?

4

Advantages of cooperative communications

cooperative

communications

PerspectivesOutage Probability

Communication Model


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5

Virtual MIMO system

cooperative

communications

PerspectivesOutage ProbabilityCommunication Model

...

Usern

User2

User1

Multi-user

...


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6

Scheme of Cooperative Relaying

cooperative

communications

PerspectivesOutage Probability

Communication Model

Transmitted Signal

Retransmitted signal

Source

Relay

Destination


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7

Relaying Strategies

cooperative

communications


Amplify-and-Forward : the relay simplyamplifies the received signal from source

and transmits it to destination.

AF Decode-and-Forward : the relay decodesthe received signals and transmits thefresh codeword using the same code asthe one used at the source.

DF Detect-and-forward : the relay attempts

to detect the sources symbols and thenretransmits the detected symbols.

DeF


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Amplify and fAmplify and forwardcooperative

communications


8

Source

Relay

Destination


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decode and fAmplify and fDecode and forwardcooperative

communications


99

Source

Relay

Destination


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decode and fAmplify and fDetect and forwardcooperative

communications


1010

SourceDestination

Relay


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Communication model

Communication

modelPerspectivesOutage Probability

cooperative

communications

Transmitted signal

Retransmitted signal

user1 user2

R-N

S-N

D-N


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Global expression

Outage probability PerspectivesCommunication modelcooperative

communications

P out{1} =(1-Pout

(s-r){1}).Pout(s,r-d){1}+ Pout

(s-r){1}. Pout(s-d){1}

P out{2} =(1-Pout

(s-r){2}).Pout(s,r-d){2}+ Pout

(s-r){2}. Pout(s-d){2}

User2

User1

???


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PerspectivesOutage probabilityCommunication modelcooperative

communications

Disadvantages of classical schemes

High Energy consumption.

large time delay.

Complexity.

Challenge

To perform the adaptation to the channel.

To prolong the network lifetime.

whywhy thethe need forneed for a newa new strategy?strategy?


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communications

solution of a new strategy

Switching adaptively between AF andDF .

Birth of the ybrid

Good adaptation to the channel.

Decreased energy consumption.

very small time delay.


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communications

How to switch?

Selection criterias:

-The Help of Error detection code .

-The Use of known threshold InSignal-to-noise ratio(SNR).


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communications

Example of a method that uses a Power Constraint

One User in cooperation protocol over a Rayleigh Fading ChannelOne User in cooperation protocol over a Rayleigh Fading Channel


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communications

Outage performance of hybrid forwarding comparing withAFOutage performance of hybrid forwarding comparing withAF

and DF.and DF.


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communications

Very little research has been focused on outage

probability of the Hybrid forwarding.

Futur works may include more users in the

hybrid forwarding strategy.


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CONCLUSION

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outage probability of cooperative communication

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