1. 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

2. 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

3. TowersBuoys Remote (Shore Radar & Estuaries) Iridium-enabled Near Real Time Observations Slocum Gliders

4. NCCOOS Initial Deployment (in SABSOON waters) Navy TACTS towers (Tactical Aircrew Combat Training System Range) Move to Oceana Range

5. 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 Current Profile, Current Speed, Current Direction, Conductivity, Temperature, Pressure, Salinity, Density, other…

6. 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) Instrument limitations (serial/analog IO) Limited development environment 68332 CPU 256K RAM / 256K Flash Low power (150 mA) -40°C to +85°C 95% relative humidity

7. 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) -10°C to +55°C

8. NCCOOS component of SEACOOS Volumetrics: 2MB/day Link: PPP Transport: FTP

9. Iridium Pioneers Iridium 9500 Rated 2.4 kbits/sec -30°C to 60°C 85% relative humidity ~1A @ 4.4VDC average

10. Start Data AcquisitionData Transfer CommLib Win CE RAS

11. CommLib Microsoft Embedded VC++ Callable from Visual Basic Chunked FTP transfer (InternetWriteFile) Logs errors and statistics API DllMain SendFile pollFinished pollSuccessful

12. 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.

13. Metrics Median burst rate: 7503 bytes/sec Average power consumption: 1 watt

14. median 75 quartile 25 quartile Transfer Rates

15. 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

19. To Do: GPL More statistics (Connect rate, connect time) New API Protocol logging 9505 modem Iridium Data Gateway ISAPI Linux

20. 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();

21. cbc@unc.edu http://www.unc.edu/~cbcoasis http://www.seacoos.org