KEY TECHs

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KEY WIRELESS NETWORKING TECHNOLOGIES IN THE NEXT
DECADE - OVERVIEW

• WIRELESS LANs
• SATELLITE NETWORKS
• AD HOC SENSOR NETWORKS (MARIO GERLA, I.
  AKYILDIZ)
• WIRELESS MESH NETWORKS (NITIN VAIDYA, HARI B.)
• WiMAX
• COGNITIVE RADIO NETWORKS
• (MOBILE SOCIAL NETWORKS!!)

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COMMUNICATION/NETWORKING IN CHALLENGING
ENVIRONMENTS

• UNDERGROUND APPLICATIONS
• UNDERWATER APPLICATIONS

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Wireless Underground Sensor NetworksI.F.
Akyildiz and Erich Stuntebeck, Wireless
Underground Sensor Networks Research
Challenges, Ad Hoc Networks (Elsevier) Journal,
Nov. 2006.
Sink

• Soil Condition
• Sensor
• Water
• Salinity
• Temperature

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APPLICATIONS

• Sports field monitoring
• Golf courses
• Soccer fields
• Baseball fields
• Grass tennis courts

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FURTHER APPLICATIONS

• Infrastructure monitoring
• pipes
• electrical wiring
• liquid storage tanks
• underground fuel tanks
• septic tanks
• Border Patrol and Security

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FURTHER APPLICATIONS

• Coal Mines (TUNNELS)
• Diamond/Gold/Platinum Mining (TUNNELS)

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Underground Channel Challenges
Parameter Effect on Path Loss
Frequency
Water content
Temperature
Sand particles in soil
Clay particles in soil

• Dynamic Channel

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Underground Challenges

• Power Constraints
• Difficult/impossible to change the batteries for
  underground devices
• High radio power necessary due to extreme path
  losses
• Low data rate
• Channel conditions are best at low carrier
  frequencies
• Less bandwidth is available at lower frequencies

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Underground Challenges

• Antenna Design
• Extremely Lossy Environment
• Strong FEC needed to help overcome weak signals,
  but must not use excessive energy in processing

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Underground Challenges

• EM Waves or
• Magnetic Induction or
• Seismic Waves????

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Underground Challenges

• MODULATION (EARLY WORK ? ANALOG COM.)
• (LATELY04 ? QPSK, QAM 16, QAM 32) 4kHz
  carrier,10W, 2kbps)
• Capacity Study
• Tradeoff between Capacity and Reliability
• MAC
• Routing
• End-to-End Reliability
• Error Control
• Packet Size

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UNDERWATER NETWORKINGI.F. Akyildiz, D. Pompili,
T. Melodia, Underwater Acoustic Sensor Networks
Research Challenges, Ad Hoc Networks (Elsevier)
Journal, March 2005

• Available bandwidth is severely limited
• UW channel is severely impaired (in particular
  due to
• multi-path and fading)
• Very long (5 orders of magnitude higher than in
  RF
• terrestrial channels) and extremely variable
  propagation
• delays

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CHARACTERISTICS OF UNDERWATER NETWORKS

• Very high bit error rates and temporary losses
  of
• connectivity (SHADOW ZONES)
• Battery power is limited and usually batteries
  cannot be
• recharged no solar energy!!

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Transmission Loss (URICK PROP. MODEL)
Attenuation due to multipath
Attenuation due to absorption
Attenuation due to geometric spreading
TL increases with increasing freq. distance
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Our Contributions for UW-ASNs
SensorApp
Developed _at_BWN-Lab -AcousticProp
Model -AcousticChannel -AcousticPhy -CDMA-based
MAC -SensorRouting
WirelessAgent
SensorRouting
LL
Queue
CDMA-based MAC
AcousticPhy
AcousticProp Model
AcousticChannel
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CROSS LAYER SOLUTION D. Pompili and I.F.
Akyildiz, Cross-layer Protocol Suite for
Underwater Acoustic Sensor Networks, July 2007
Cross-Layer Melting
Application Layer
Application Layer
Transport Layer
Network Layer
Energy Management Plane
Energy Management Plane
Cross -Layer MODULE
Cross-Layer Management Plane
Cross-Layer Management Plane
MAC Layer
PHY Layer
Our View

• Traditional Approach

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WHAT IS THE STATUS?

• PAPER WRITING RACE STARTED !!!!
• COMMUNICATION PROTOCOLS !!!
• MODULATION TECHNIQUES ((D) PSK, 16 QAM), OFDM??
• SYNCHRONIZATION ALGORITHMS
• LOCALIZATION ALGORITHMS
• CAPTURING THE MOBILITY OF AUVs
• SECURITY

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WHAT IS THE STATUS?

• CAPACITY ANALYSIS
• TRADEFOFF RELIABILITY vs CAPACITY
• DEPLOYMENT (TOPOLOGY) ALGORITHMS
• ERROR CONTROL (FECs, HYBRID ARQs???)
• IN-NETWORK CODING (AGGREGATION/FUSION???)
• MULTIMEDIA COMMUNICATION
• Etc.etc..

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