Acoustic Modem Pres

8/3/2019 Acoustic Modem Pres

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Wireless Underwater

CommunicationsNetwork

ECE Senior Design Team #88Spring-Fall 2007

Roy BehymerKrenar Jusufi

Mary Hoyer

Advisor - Shengli Zhou


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Background

Goal is to expand two-node underwater,acoustic network to three-node relay networkwith motion sensor


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Packet Structure64 bytes

1 1 1 1 1 1 57 1

msgN

ext

msgSrc

msgD

est

msgSe

qNo

msgNo

Pack

msgUseful

msgD

ata

msgErr


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Packet Structure64 bytes

Next Hop Address

Source Address

Destination Address Sequence Number

Number of Packets

Number of Bytes of Useful Data Data (57)

Error Check


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Receiving

Compare Destination and Computer info.

Relay message if not at destination

Process remainder of message if at destination Broken down using packet structure

Display message


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Matlab Lessons Learned

Characters / Strings best handled via arrays

not as friendly as VB

built-in functions not as versatile

Start with structure and maintain it whiledeveloping code

Document code

Document function and file dependencies


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Breaking the Code

Transceiver_RNS

main, open this to runprogram

SendDataCallbackthis is used by Transceiver_RNS

to send signal SelectRecordCallbackthis is used by

Transceiver_RNS to receive signal

contReceiverv2same as SendDataCallback

writefileCLEARclears writefile


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Breakdown of SendDataCallback

writefileTX

converts symbols to ascii and writes into file num2binmapfinds binary equivalent

contReceiverv2continuously monitors incoming data, if trigger ismet goes to autoautocorr

zTxRNSv2processes and sends data readfileconverts ascii character to text to binary

num2binmapfinds binary equivalent

CCQPSKencodeperforms coding on binary vector then QPSK mapping

insertnullinsert null subcarriers and pilot tones

synchcpofdm

cyclic prefix-ofdm writefileconverts symbols to ascii and writes to file

Writetodisplets us know message was sent


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contReceiverv2

analyzedata

analyzes data autoautocorrauto correlation to find useful data

zRxV2main receiver file, receives and processes data CFOchjointestimation2uses channel estimation to determine

carrier frequency offset removeqrtrdataV2removes pilot tones and null subcarriers

BERcountfinds raw bit error rate

Ch_estimationprovides time and frequency domain channelrepresentation

dem_wi_decoder

QPSK signals demodulation

binaryBERfinds BER after decoding

writefileconverts symbols to ascii and writes into file


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Goals

a) Draw flow chart based on dependency reports ofcodes

b) Give description of each functions and sub functions

c) Delete files unused

d) Combine small files into large file for organization

e) Clear variables before each run so there is less chance

of failure in testingf) Put all parameters as global variable


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Motion Sensor

Need real-time, continuous data acquisition

MATLAB does not support our motion sensor

Solution: use LabView VI for interface Must convert LabView VI to MATLAB function

Math Interface Toolkit


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Timeline

Month

Short Term

Goals Long Range GoalsFebruary Review / Research

Three-node relay network in air with motionsensor

March Ordering parts (air)

AprilHardware ModsSoftware Mods

May

Review / Research SummerJune

July

August Underwater Testing

Three-node relay network in waterSeptember

Debugging

Hardware ModsSoftware Mods

October Hardware Mod Three or four node full network in air and waterwith two motion sensorsNovember Software Mods

December Final Write-up and Demonstration


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Budget

Product Price

M-Audio Mobile Pre USB Audio Interface withPreamp (2)

$238.00

XLR Cable (2) $15.65

Audix TR-40 Microphones (2) $379.94

Microphone Stands (2) $23.94

Motion Sensors (2) $208.00

LabView Math Interface Toolkit (1) ~$100.00

Total ~$965.53


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Conclusion

Background

Project Description

Technical SpecificationsTimeline

Budget


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Acoustic Modem Pres

Documents

Transcript of Acoustic Modem Pres