Power Minimization by Separation of Control and Data Radios

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Power Minimization by Separation of Control and
Data Radios
Jessica Feng and Miodrag Potkonjak
jessicaf, miodrag _at_ cs.ucla.edu
Computer Science Dept., University of California,
Los Angeles, CA
IEEE CAS Workshop, Sep 2002
jessicaf_at_cs.ucla.edu
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Why Wireless 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 NetworksTwo Alternatives
Ad-hoc (multihop) network
Cell-based architecture
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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

jessicaf_at_cs.ucla.edu
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Obstacles

• Energy is the main constraint
• Communication is the dominate component of energy
  consumption
• EDSP EATMEGA EBT 1 4.75 1585
• Range, Error rate f (channel conditions, symbol
  rate bandwidth, transmit RF power
  level)

Power management of radios is extremely
important since wireless communication is a major
power consume during system operation.
jessicaf_at_cs.ucla.edu
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Related Work

• Raghunathan, V. Schurgers, C. Park, S.
  Srivastava, M.B.
• Energy-Aware Wireless Microsensor Networks
• IEEE Signal Processing magazine, 2002

• Rabaey, J. M. Ammer, M.J. Silva Jr, J.L.da
  Patel, D. Roundy, S.
• PicoRadio Supports Ad Hoc Ultra-Low Power
  wireless Networking
• IEEE Computer, 2000

• Thomson, J. Baas, B. Cooper, E.M. Gilbert,
  J.M. and others.
• An integrated 802.11a baseband and MAC
  processor
• IEEE International Solid-State Circuits
  Conference, 2002

• McFarland, B. Chesson, G. Temme, C. Meng,
  T.
• The 5-UP/sup TM/ protocol for unified
  multiservice wireless networks
• IEEE Communications Magazine, 2001

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Idea Instruction and Data Memory Organization
Separate memories for data and instructions.
Single memory for both data and instructions.
Instructions are fetched and operands from data
memory to be fetched or stored all in a single
machine cycle.


Cost, Design complexity, Small in size


Bandwidth, Access flexibility
More complex, additional costs
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Idea Network Processor Architecture
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Key Idea Separation of radios in a single node
High power, high bandwidth Radio
Low power- consuming Radio

• Motorolas
• idea

Waking up the Communication radio
Communication operations
Control radio Waking up the Data radio conduct
all control related, low symbol rate and high
frequency tasks

• We propose

Data radio Transmitting and receiving sensor
data
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Putting it all togetherCoordination of Data and
Control radios

• High Speed
• Thinker The control radio makes all the
  decisions
• Two parts of radio Transmitting and Receiving
• Communication modes
• Key idea
• Control radios listen none stop
• Data radio listening is EXPENSIVE

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Simulation
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Advantages and Trade-offs

• Advantages
• Lower power consumption
• Better fault tolerance

• Trade-offs
• Deciding the proper radios
• More complex design
• Additional costs

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Conclusion

• Energy is the major constraint

• Communication is the major component in power
  consumption

• How to resolve it Separation of control radio
  and data radio
• Control Decision making, waking up
  communication radio
• Data Communication operations

• Preliminary study confirms the approach

jessicaf_at_cs.ucla.edu