enhanced slotted aloha protocols for underwater sensor networks with large propagation delay kai...
TRANSCRIPT
![Page 1: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/1.jpg)
Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay
Kai Chen† Jianhua He§
Yi Zhou‡ Haibing Guan‡
†School of Information Security and Engineering,
Shanghai Jiaotong University, China.
‡School of Electronic, Information and Electrical Engineering,
Shanghai Jiaotong University, China.
§School of Engineering, Swansea University, UK.
IEEE VTC 2011
![Page 2: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/2.jpg)
Outline
• Introduction• System model• SA-ALOHA• ISA-ALOHA• Simulation• Conclusion
![Page 3: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/3.jpg)
Introduction
• Underwater sensor networks(UWSNs) have attracted large research interests from both academy and industry
• Due to the importance of MAC protocols for UWSNs– Design and analysis of MAC protocols
![Page 4: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/4.jpg)
Introduction
• Among the existing MAC protocols in shared wireless medium– ALOHA protocols
Pure-ALOHA
Time
A
B
C
DATA
DATA
DATA
DATA
DATA
Slotted-ALOHA
Time
A
B
C
DATA
DATA
DATA
DATA
DATA
![Page 5: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/5.jpg)
Introduction
• This frame can be received successfully– There are no other frames arrival at node in
conflict free period (Pcf)
],[ ,,,, fAikifAikicf TTtTTtP
ti,k: node i send the kth frame to node ATi,A: actual propagation delayTf: frame transmission time
![Page 6: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/6.jpg)
Introduction
• Conflict free for two different frame transmission
fijij TTt
∆tij: the difference of start for two frame transmission∆Tij: the difference between propagation delay Ni to NA and that Nj to NA
Tf: frame transmission time
![Page 7: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/7.jpg)
Introduction
• RF network scenarios
fij Tt
Pure-ALOHA Slotted-ALOHA
protocol
∆tij Any value Multiple of Tf
throughput 0.18 0.36
Time Time
A
B
C
A
B
C
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
TIME
Sender
Receiver
Radio wavePropagation speed : 3*108 m/s
![Page 8: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/8.jpg)
Pure-ALOHA Slotted-ALOHA
protocol
∆tij random Multiple of Tf
∆Tij random random
throughput 0.18 0.18
Introduction
• UWSN scenarios
fijij TTt Pure-ALOHA Slotted-ALOHA
protocol
∆tij random Multiple of Tf
∆Tij random random
Time Time
A
B
C
A
B
C
DATA DATA
DATADATA
DATA
collisionDATA
DATA
DATA
collision
TIMEPropagation delay
UnderwaterSender
Receiver
Acoustic wavePropagation speed : 1500 m/s
![Page 9: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/9.jpg)
Introduction-motivation
• The performance of Aloha in UWSNs can drop quickly with increasing propagation delay
![Page 10: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/10.jpg)
Goal
• Reuse the idea of synchronous transmission in S-Aloha protocol– SA-ALOHA– ISA-ALOHA• Improvement for the SA-ALOHA
![Page 11: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/11.jpg)
System model & Assumption
• Single hop star topology with a central control node A
• Fixed N ordinary nodes• Position information• Time synchronized• Each ordinary nodes may occasionally send
data frames to the central control node
![Page 12: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/12.jpg)
SA-ALOHA
• Example of frame transmission and reception
![Page 13: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/13.jpg)
SA-protocol
• Calculation of Tpre
slotAiipre TTT mod,,
Ti,A: propagation delat of node i to node ATslot: slot size
![Page 14: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/14.jpg)
SA-protocol
• Problem– Propagation delay is not accurate
AiAierrAi TTT ,,,
~
Terr: Estimation error of Ti,j
T~i,A: estimated value of Ti,j
![Page 15: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/15.jpg)
Tslot,isa: Tslot for ISA protocol
ISA-protocol
• Solution
]),1[(),max( , NiT errAi
max* ef TkT
maxeT
isaslotT , incslot TT
Tinc: the increment of time from Tslot for Tslot,isa
![Page 16: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/16.jpg)
ISA-protocol
• Solution
Sender , N1
Sender , N2
Receiver , NA
Tslot,isa
=Tf+k*Temax
Frame1 Tx
Frame2 Tx
Frame1 Rec
Frame2 Rec
Tolerant of the error of estimation
![Page 17: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/17.jpg)
Simulation
parameter value
Ordinary node 50
Transmission range 1000
RF UWSN
Propagation speed 3*108 m/s 1500 m/s
Frame length 512 bytes 50 bytes
Data rate 2 Mbps 2 kbps
Tf 2.048 ms 200 ms
Tslot = 1.01*Tf 2.06848 ms 202 ms
1000 mCenter node
![Page 18: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/18.jpg)
Simulation result
![Page 19: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/19.jpg)
Simulation result
![Page 20: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/20.jpg)
Simulation result
![Page 21: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/21.jpg)
Simulation results
![Page 22: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/22.jpg)
Simulation result
Temax = 33 ms
![Page 23: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/23.jpg)
Conclusion
• In this paper, the authors investigated the performances of Aloha protocols in (UWSN)– Long propagation delay• SA-protocol• ISA-protocol
• Simulation results demonstrate the effectiveness of our proposed protocols
![Page 24: Enhanced Slotted Aloha Protocols for Underwater Sensor Networks with Large Propagation Delay Kai Chen † Jianhua He § Yi Zhou ‡ Haibing Guan ‡ †School of](https://reader035.vdocuments.net/reader035/viewer/2022062722/56649f2f5503460f94c48850/html5/thumbnails/24.jpg)
24
Thanks for your at tention