r2d2 project (ep/l006251/1) - research objectives & outcomes
TRANSCRIPT
R2D2 A PROJECT FUNDED BY EPSRC UNDER THE FIRST GRANT SCHEME
E P / L 0 0 6 2 5 1 / 1
NETWORK ERROR CONTROL FOR RAPID AND RELIABLE DATA DELIVERY{Research Objectives & Outcomes}{Principal Investigator} Dr Ioannis Chatzigeorgiou - [email protected] {Postdoctoral Research Associate} Dr Andrea Tassi - [email protected]{Affiliated Member} Amjad Saeed Khan - [email protected]
http://www.lancs.ac.uk/~chatzige/R2D2/
at a glance
A I M S & A S P I R AT I O N S
• 18-month EPSRC research project on network error control aspects
• Design novel mathematical frameworks - To identify key relationships between system and transmission parameters, understanding network dynamics and optimise network-coded architectures
• Delve into practical applications - Ultra-reliable communications, delay constrained applications, green and energy-efficiency architectures
R E S E A R C H A C T I V I T I E S
• 4G and 5G Cross-Layer System Optimization for Video Multicasting
• Design of On-the-fly Rateless Decoders
• Sparse Network Coding Schemes with Minimum Decoding Complexity
• Novel Network Coding Schemes for Relay Networks
✴ So far, results have been presented in 4 conference and 1 journal papers
R E S E A R C H A C T I V I T I E S
• 4G and 5G Cross-Layer System Optimization for Video Multicasting
• Design of On-the-fly Rateless Decoders
• Sparse Network Coding Schemes with Minimum Decoding Complexity
• Novel Network Coding Schemes for Relay Networks
✴ So far, results have been presented in 4 conference and 1 journal papers
4 G / 5 G S Y S T E M O P T I M I Z AT I O N
• Multimedia multicast services are becoming a challenge for service providers
• Video content delivery represented 53% of the global mobile Internet traffic in 2013 and is expected to rise to 67% by 2018
• LTE-Advanced allows multicast and broadcast communications via the eMBMS framework
• Modern video compression standards (such as, H.264/AVC, H.264/SVC, H.265) allow the generation of scalable video contents
4 G / 5 G S Y S T E M O P T I M I Z AT I O N
• Multimedia multicast services are becoming a challenge for service providers
• Video content delivery represented 53% of the global mobile Internet traffic in 2013 and is expected to rise to 67% by 2018
• LTE-Advanced allows multicast and broadcast communications via the eMBMS framework
• Modern video compression standards (such as, H.264/AVC, H.264/SVC, H.265) allow the generation of scalable video contents
✴ So? Let’s simply use what we already have!
4 G / 5 G S Y S T E M O P T I M I Z AT I O N
• Too many system- and transmission-related parameters that can be tuned
• What does the Service Provider want? To meet Service-Level Agreements SLAs with the minimum amount of radio resources
• What does the user want? To get an acceptable uninterruptible user experience
Photo credits: https://www.nasa.gov
4 G / 5 G S Y S T E M O P T I M I Z AT I O N
Base Layer
Base + 1st Enhancement Layers
Base + 1st + 2nd Enhancement Layers
BS
QoS Zone 1QoS Zone 2QoS Zone 330% of UEs60% of UEs
99% of UEsPhoto credits: http://www.animatedmoviewallpapers.com/
• We refer to H.264/SVC broadcast video streams
4 G / 5 G S Y S T E M O P T I M I Z AT I O N
⊗⊗⊕
x1 xk1 xK. . .. . .
yj
xk2
Source message
Coded packets
gj,2gj,1
Photo credits: http://www.animatedmoviewallpapers.com/
• We refer to H.264/SVC broadcast video streams
• Each layer is broadcast via a Random Linear Network Coding (RLNC) strategy
4 G / 5 G S Y S T E M O P T I M I Z AT I O N
Distance (m)
Maxim
um
PSNR
ρ(d
B)
90 110 130 150 170 190 210 230 250 270 2900
5
15
25
35
45
55
t̂1t̂2t̂3
MrT
Heu. NO−SA
Heu. NO−MA
Heu. EW−MA
⌧ = 73
⌧ = 88⌧ = 88
All the proposed strategies meet the
coverage constraintsMrT
Classic NC(NO-SA)
Code and Resource Multiplexing
(EW-MA)
Resource Multiplexing
(NO-MA)
PSNRlayers 1+2+3 PSNR
layers 1+2
PSNRlayers 1
• Minimization of bandwidth. User SLAs are constraints
4 G / 5 G S Y S T E M O P T I M I Z AT I O N
x position (m)
yposition(m
)
−500 −300 −100 100 300 500 700
−200
−100
0
100
200
300
400
500
600
700
x position (m)
yposition(m
)
−500 −300 −100 100 300 500 700
−200
−100
0
100
200
300
400
500
600
700
45.8
45.8
45.8
45.8
45.8
45.8
45.8
45.8
45.845.
8
35.9
35.9
35.9
35.9
35.9
35.9
35.9 35.9
35.9
35.935.9
27.9
27.9
27.9 27.9
27.9
27.9
27.927.9
27.9
27.9
27.9
27.9
E"SAMrT
45.8
45.8
x position (m)yposition(m
)−500 −300 −100 100 300 500 700
−200
−100
0
100
200
300
400
500
600
700
x position (m)yposition(m
)−500 −300 −100 100 300 500 700
−200
−100
0
100
200
300
400
500
600
700
46.4
46.4
46.4
46.4
46.4
46.4
46.4
46.4
46.4
46.4
46.4
46.4
39.9
39.9
39.9
39.9
39.9
39.9
39.9
39.9
39.9
39.9
39.9
33.4
33.4
33.4
33.4
33.4
33.4
33.4
33.4
28.1
28.1 28.1
28.1
28.1
28.1
28.1
28.1
28.1
46.4
46.4
E"SAMrT
• Maximization of the system profit-cost ratio, i.e., no. of video layers recovered by users over the bandwidth used.
• User SLAs are used as constraints
S PA R S E N E T W O R K C O D I N G S T R AT E G I E S
• What is the price of the RLNC simplicity? The computational complexity of the decoder
• The decoding complexity depends on algebraic features of the code (finite filed size) and the number of source packets forming (on average) each coded packet
✴ So? Let’s reduce the linear combination degree!
S PA R S E N E T W O R K C O D I N G S T R AT E G I E S
• This problem involves sparse random matrices…
• Since 1997, only 4 papers used accurate methods in order to shed some light onto the topic
• Engineering approach: Let’s put some bounds!
Photo credits: http://curvaturasvariantes.com/
S PA R S E N E T W O R K C O D I N G S T R AT E G I E S
Probabi l i ty of selecting zero
Delay
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.95
10
15
20
25
30
35
PER = 0PER = 0 .25PER = 0 .5
Sparsity increases
Decoding complexity decreases
R2D2 A PROJECT FUNDED BY EPSRC UNDER THE FIRST GRANT SCHEME
E P / L 0 0 6 2 5 1 / 1
NETWORK ERROR CONTROL FOR RAPID AND RELIABLE DATA DELIVERY{Research Objectives & Outcomes}{Principal Investigator} Dr Ioannis Chatzigeorgiou - [email protected] {Postdoctoral Research Associate} Dr Andrea Tassi - [email protected]{Affiliated Member} Amjad Saeed Khan - [email protected]
http://www.lancs.ac.uk/~chatzige/R2D2/
at a glance