Telemetry for a Coastal Ocean Observing System

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Telemetry for a Coastal Ocean Observing
System Preliminary Results using the Iridium
System Chris Calloway, Sara Haines, Collin
McKinney, Luke Stearns, Harvey Seim SEACOOS /
NCCOOS / UNC-CH Dept. of Marine
Science http//www.seacoos.org
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Southeast Atlantic Coastal Ocean Observing System
(SEACOOS) A System of Subregional Systems
Five Iridium efforts UNC NCCOOS towers UNC
Slocum Glider USC Caro-COOPS buoys GA Tech
TriAXYS buoys Univ. Miami SWAMP profiler
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Iridium-enabled Near Real Time Observations
Remote (Shore Radar Estuaries)
Slocum Gliders
Towers
Buoys
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NCCOOS Initial Deployment (in SABSOON
waters) Navy TACTS towers (Tactical
Aircrew Combat Training System Range) Move to
Oceana Range
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Tower Instrumentation Atmospheric Temperature,
Pressure, Humidity, Rainfall, Infrared, Visible
spectrum, Wind speed, Wind direction,
other. In-water/Near-surface Wave pressure,
Tidal height, Wave height, Wave
period, Conductivity, Temperature, Pressure,
Salinity, Density, other In-water/Near-bottom Cu
rrent Profile, Current Speed, Current Direction,
Conductivity, Temperature, Pressure,
Salinity, Density, other
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Current technology (Caro-COOPS buoys) ISU to
ISU Dedicated data logger (ZModem) Offshore in
periodic autoanswer Shore dials in to observing
platform Low throughput (100 bytes/sec) Instrumen
t limitations (serial/analog IO) Limited
development environment 68332 CPU 256K RAM / 256K
Flash
Low power (150 mA) -40C to 85C 95 relative
humidity
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Developing technology (NCCOOS towers) ISU to
ISP SBC with instrumentation buss ISU calls
home Connect to generic repository High
throughput Flexible instrumentation Visual
development environment i486 CPU 16MB RAM / 12MB
Flash / 512MB PCMCIA
Low power (330ma) -10C to 55C
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NCCOOS component of SEACOOS Volumetrics
2MB/day Link PPP Transport FTP
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Iridium Pioneers Iridium 9500 Rated 2.4
kbits/sec -30C to 60C 85 relative
humidity 1A _at_ 4.4VDC average
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Start
Data Acquisition
Data Transfer
CommLib
Win CE RAS
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CommLib Microsoft Embedded VC Callable from
Visual Basic Chunked FTP transfer (InternetWriteF
ile) Logs errors and statistics API DllMain Send
File pollFinished pollSuccessful
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Error recovery strategy 1) Dial error hang up
and retry if off hook and not connected else
disconnect and retry. 2) Dial timeout hang up
and retry if off hook and not connected else
disconnect and retry. 3) Dial retry limit
reached Reboot modem. 4) Disconnect
error/timeout Reboot modem. 5) Hangup
error/timeout Reboot modem. 6) No IP
disconnect and redial. 7) No IP retry limit
reached Reboot modem. 8) No TCP connectivity
disconnect and redial. 9) No TCP connectivity
retry limit reached Reboot modem. 10) FTP
error retry FTP if nonfatal, else disconnect and
redial. 11) FTP timeout/retry limit reached
disconnect and redial. 12) Modem reboot limit
reached turn off modem and wait awhile.
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Metrics Median burst rate 7503
bytes/sec Average power consumption 1 watt
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Transfer Rates
75 quartile
median
25 quartile
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Transfer Rate Statistics (bytes per
second) Points 460 Average 6563 Median
7503 25 Percentile 4417 75 Percentile 8334 Std
Dev 3047 Minimum 200 Maximum 13582
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To Do GPL More statistics (Connect rate,
connect time) New API Protocol logging 9505
modem Iridium Data Gateway ISAPI Linux
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COMMLIB_API BOOL sendFile(TCHAR localFilePath,
             
TCHAR localFileName,     
          TCHAR remoteFileName)
COMMLIB_API BOOL pollFinished(TCHAR
localFilePath,
                    TCHAR localFileName)
COMMLIB_API BOOL pollSuccessful(TCHAR
localFilePath,
                  TCHAR localFileName)
COMMLIB_API BOOL retractFile(TCHAR
localFilePath,
                 TCHAR localFileName)
COMMLIB_API INT locateFile(TCHAR
localFilePath,
               TCHAR localFileName)
COMMLIB_API INT queueDepth() COMMLIB_API
BOOL relocateFile(TCHAR localFilePath,
             
TCHAR localFileName,
            int   
newOrdinal) COMMLIB_API TCHAR queryFile(int
ordinal) COMMLIB_API BOOL clearQueue()
COMMLIB_API BOOL shutDownComm() COMMLIB_API
BOOL restartComm() COMMLIB_API BOOL
isCommActive()
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cbc_at_unc.edu http//www.unc.edu/cbcoasis http//
www.seacoos.org