SystemArchitectures for Sensor Networks: Issues, Alternatives, and Directions

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System-Architectures for Sensor Networks Issues,
Alternatives, and Directions
Jessica Feng, Farinaz Koushanfar, and Miodrag
Potkonjak
CS Dept., University of California, Los Angeles,
CA EECS Dept., University of California,
Berkeley, CA
ICCD, September 2002
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Why Sensor Networks?

• Contaminant Transport Monitoring

• Marine Microorganisms

• Habit Sensing Array

• Seismic Monitoring

Bridge between the Internet and the physical world
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Architecture of Sensor NetworksNetwork level
Cellular network
Ad-hoc (multihop) network
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Architecture of Sensor NetworksComponent level
Power supply Sensor
Processor Memory Radio Actuator
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Architecture of Sensor NetworksSensor node
Courtesy to System Architecture Directions for
Networked Sensors By
Hill,J. Szewczyk,R. Woo,A.Hollar,S.Culler,D.a
nd Pister,K

• Schematic of a network sensor platform

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Talk Objectives

• Identifying requirements for typical SN
  applications
• Identifying relevant technological trends
• Identifying the balanced design
• Techniques for design and the usage of the design
  components
• Overall node architecture and trade-offs

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Presentation Organization

• Global view and requirements
• Individual components of SN nodes
• Sensor network nodes
• Wireless SNs as embedded systems

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Application trends
General Purpose of Computing

• 1960s
• Military, scientific computing
• Bach computing

• 1970s
• Mainframe
• Timesharing, terminals

• 1980s
• Mini-computers, workstations
• Company level computing

• 1990s
• PCs
• Affordable, easily accessed, packet software

• 2000s
• Internet
• Secure, peer-to-peer network access

Military, Interactive
Researchers ? Big firms ? Small firms ?
Individuals ? individuals
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Technology trends
Intel vs. Duracell

• No Moores Law in batteries 2-3 per year growth
• Alternatives of batteries
• Full cells
• Converting vibration to electric energy

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Design Objectives

• Small physical size
• Low power consumption
• Concurrency-intensive operation
• Diversity in design and usage
• Robust operations
• Security and privacy
• Compatibility
• Flexibility

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Individual Component Storage

• Trade-off between memory space communication
  cost

 

• Current technologies

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Individual Component Power Supply

• The main technological constraints for SN nodes

• Current technologies

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Individual Component Sensors
 

• Current technology bottleneck

• Not progressing as fast as semi-conductors

• Inherently noisy data

• Prone to faults

• Difficult to maintain

• Needs for calibration

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Individual Component Radios

• Dominates overall energy budget

• 3 design layers

• The concept of two radios
• Data communication operations
• Control The brain, waking up the data radio,
  decision-making

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Small is Beautiful Approach
A routing topology created by a collection of
distributed sensors
A sample configuration of a network sensor
Courtesy to System Architecture Directions for
Networked Sensors By
Hill,J. Szewczyk,R. Woo,A.Hollar,S.Culler,D.a
nd Pister,K
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Classical Balanced Approach
iBadge Architecture
iBadge Sensor Characteristics
Courtesy to System Design of iBadge for Smart
Kindergarten By
Locher,I. Park,S. Savvides,A. Srivastava,M
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Sensor Centric Approach
Nothing is in the understanding, which was not
first in the senses. --- John Locke
(1632-1704)

• Key question

How to place sensors so that multi model
sensor fusion can be conducted efficiently
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Conclusion

• Sensor network is the bridge between the Internet
  and the physical world
• 3 components
• Network level
• Node level
• Individual components level
• Design approaches
• Small is beautiful
• Classic balanced
• Sensor centric
• High impact researches with big time challenges