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後卓越計畫進度報告曾煜棋老師實驗室

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A Link-layer Protocol for Event-driven WSNs

Joint two subissues Exploiting the spatial correlation of sensor

data Designing a specific MAC protocol

Sink

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Basic IdeaSink

TDMA

CSMA

Built on top of any CSMA-based protocol

A CSMA-basedMAC Protocol

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Proposed Solution Two modes

ES mode & NES mode

Issues involved in the ES mode Entering the ES Mode

The first slot stars on-the-fly in an event-driven manner Slot Assignment Slot Size Synchronization Leaving the ES Mode

Energy efficiency Combine our protocol with the LPL (Low Power

Listening)Chih-Yu Lin, Yu-Chee Tseng, and Ten-Hwang Lai, “Exploiting Spatial Correlation on the Link Layer for Event-driven Sensor Networks” (Submitted to INFOCOM 2008)

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Simulation Results

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CSMA CSMA-SSC SCMAC-SSC-TSA

SCMAC-TSA SCMAC-SSC SCMAC

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CSMA CSMA-SSC SCMAC-SSC-TSA

SCMAC-TSA SCMAC-SSC SCMAC

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CSMA CSMA-SSC SCMAC-SSC-TSA

SCMAC-TSA SCMAC-SSC SCMAC

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CSMA CSMA-SSC SCMAC-SSC-TSA

SCMAC-TSA SCMAC-SSC SCMAC

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Implementation