MAC Protocol Implementation on Atmel AVR for Underwater Communication

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MAC Protocol Implementation on Atmel AVR for
Underwater Communication
CSC 714 Real Time Computer Systems

• by Shaolin Peng

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Aloha Protocol
MACA Protocol
Atmega168
Small Sparse Network Small Packet Size
Development Platform STK500 AVR Studio
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Problem List

• P1 Debugging Instrument
• Set up UART communication with the HyperTerminal
  on PC
• Connect two boards using wire as a start
• P2 Starvation
• Wait only after sending, not after receiving
• P3 Flexible Length Packet Receiving
• Receive the first two bytes, decode and decide
• P4 CRC Consideration
• 4 bits -gt 8 bits (x8 x2 x 1)

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Problem List 2

• P5 Random Number Generator
• ADC or Timer Counter
• P6 No response problem
• Set maximum retries number
• P7 Hardware Limitation
• Compile different files using different
  optimization levels
• E.g. -O3 for Goertzel algorithm (critical path)
• -Os for the other files
• Text data bss total
• 14986 302 141 15429 (different
  optimization levels)
• 16380 338 109 16827 (same optimization
  level)

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Experimental Setup
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Results

• Indoors
• Aloha 27.2
• MACA 23.8
• Outdoors
• Aloha 8.1
• MACA 8.2
• Compare with MACA
• During the testing time, Aloha received almost
  twice data than MACA

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Thanks! Questions?