-
8/7/2019 Outage Probability of Cooperative Communication
1/19
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
-
8/7/2019 Outage Probability of Cooperative Communication
2/19
Introduction
Conclusion
Cooperative communications
Communication model
Outage probability
Perspectives
Outline
I
II
III
IV
V
VI
-
8/7/2019 Outage Probability of Cooperative Communication
3/19
INTRODUCTION
3
-
8/7/2019 Outage Probability of Cooperative Communication
4/19
Why cooperative communications?
4
Advantages of cooperative communications
cooperative
communications
PerspectivesOutage Probability
Communication Model
-
8/7/2019 Outage Probability of Cooperative Communication
5/19
5
Virtual MIMO system
cooperative
communications
PerspectivesOutage ProbabilityCommunication Model
...
Usern
User2
User1
Multi-user
...
-
8/7/2019 Outage Probability of Cooperative Communication
6/19
6
Scheme of Cooperative Relaying
cooperative
communications
PerspectivesOutage Probability
Communication Model
Transmitted Signal
Retransmitted signal
Source
Relay
Destination
-
8/7/2019 Outage Probability of Cooperative Communication
7/19
7
Relaying Strategies
cooperative
communications
PerspectivesOutage ProbabilityCommunication Model
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
-
8/7/2019 Outage Probability of Cooperative Communication
8/19
Amplify and fAmplify and forwardcooperative
communications
PerspectivesOutage ProbabilityCommunication Model
8
Source
Relay
Destination
-
8/7/2019 Outage Probability of Cooperative Communication
9/19
decode and fAmplify and fDecode and forwardcooperative
communications
PerspectivesOutage ProbabilityCommunication Model
99
Source
Relay
Destination
-
8/7/2019 Outage Probability of Cooperative Communication
10/19
10
decode and fAmplify and fDetect and forwardcooperative
communications
PerspectivesOutage ProbabilityCommunication Model
1010
SourceDestination
Relay
-
8/7/2019 Outage Probability of Cooperative Communication
11/19
11
Communication model
Communication
modelPerspectivesOutage Probability
cooperative
communications
Transmitted signal
Retransmitted signal
user1 user2
R-N
S-N
D-N
-
8/7/2019 Outage Probability of Cooperative Communication
12/19
12
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
???
-
8/7/2019 Outage Probability of Cooperative Communication
13/19
13
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?
-
8/7/2019 Outage Probability of Cooperative Communication
14/19
14
PerspectivesOutage probabilityCommunication modelcooperative
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.
-
8/7/2019 Outage Probability of Cooperative Communication
15/19
15
PerspectivesOutage probabilityCommunication modelcooperative
communications
How to switch?
Selection criterias:
-The Help of Error detection code .
-The Use of known threshold InSignal-to-noise ratio(SNR).
-
8/7/2019 Outage Probability of Cooperative Communication
16/19
16
PerspectivesOutage probabilityCommunication modelcooperative
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
-
8/7/2019 Outage Probability of Cooperative Communication
17/19
17
PerspectivesOutage probabilityCommunication modelcooperative
communications
Outage performance of hybrid forwarding comparing withAFOutage performance of hybrid forwarding comparing withAF
and DF.and DF.
-
8/7/2019 Outage Probability of Cooperative Communication
18/19
18
PerspectivesOutage probabilityCommunication modelcooperative
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.
-
8/7/2019 Outage Probability of Cooperative Communication
19/19
CONCLUSION
19