1. Drifting Buoy Update: WOTAN and Iridium
METOCEAN Data Systems Limited
October 9, 2003
Drifting Buoy Update: WOTAN and Iridium
Bernie Petolas, P.Eng.
Product Manager, Buoys and Platforms
Tony Chedrawy, MBA, P.Eng.
VP Sales and Marketing
Iridium Drifter
BIO Technical Presentation on Iridium

2. METOCEAN Data Systems Limited
October 9, 2003
WOTAN
SVP BP WSD
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

3. METOCEAN Data Systems Limited
October 9, 2003
Introduction
WOTAN Buoy History and Development
WOTAN Buoy Design and Specifications
WOTAN Buoy Performance
Conclusion
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

4. METOCEAN Data Systems Limited
October 9, 2003
WOTAN Buoy History
WOTAN – Wind Observation Through Ambient Noise
METOCEAN’s electronics, hydrophone and pre-amplifier design developed in 1988
Drifting buoy design integration in 1992
Vagle Algorithm focusing on sound intensity levels between 2 kHz and 8 kHz
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

5. METOCEAN Data Systems Limited
October 9, 2003
WOTAN Development
Full sensor suite and data processing integrated to METOCEAN SVP drifters in 1996
Incorporation of Pierre Blouch’s algorithm in Average sound intensity level between 2 kHz and at 6 kHz, standard deviation between 2 kHz and at 8 kHz
Transmission of data across the full sound spectrum
Over 400 WOTAN drifters deployed !!
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

6. METOCEAN Data Systems Limited
October 9, 2003
WOTAN Design
METOCEAN WOTAN DRIFTER
16 inch diameter hull
Argos position
SST - Sea surface temperature
BP - Barometric Pressure
Drogue On/Off Sensor
Acoustic wind speed
Internal compass and wind vane for direction
Drogues cm by 92 cm centered at 15 meters
Argos M1 or M2 Data Transmit Format
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

7. METOCEAN Data Systems Limited
October 9, 2003
WOTAN Design
Barometer port
Drifter hull
Fixed vane
Hydrophone
10 metres below the sea surface
Drogue
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

8. METOCEAN Data Systems Limited
October 9, 2003
WOTAN Performance
Year
Number
Minimum
Maximum
F.O.D
Average
2000 84
124 days
582 days 2
388 days
2001
134
94 days
631 days 6
419 days
2002
128
32 days
608 days 4
407 days
Data courtesy of NOAA, UK Met Office, Meteo France, AOML, NDBC, NAVOCEANO, KORDI,
Environment Canada, Australian Bureau of Meteorology
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

9. METOCEAN Data Systems Limited
October 9, 2003
WOTAN Performance
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

10. METOCEAN Data Systems Limited
October 9, 2003
WOTAN Performance
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

11. METOCEAN Data Systems Limited
October 9, 2003
WOTAN Performance
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

12. METOCEAN Data Systems Limited
October 9, 2003
WOTAN Performance
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

13. METOCEAN Data Systems Limited
October 9, 2003
WOTAN Conclusion
Minimum lifetime of one year
Proven Air Deployment Reliability
Proven Performance in Hurricane (s)
Low POWER Consumption
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

14. METOCEAN Data Systems Limited
October 9, 2003
Iridium
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

15. METOCEAN Data Systems Limited
October 9, 2003
Iridium Introduction
Iridium data services overview
METOCEAN’s Iridium Communication Infrastructure
Drifting buoy deployed in Bering Sea
Iridium costs
Conclusions
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

16. METOCEAN Data Systems Limited
October 9, 2003
Overview of Iridium System
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

17. DBCP Technical Workshop 2003
SBD Service Overview
Internet
Iridium Gateway
Value Added Reseller Host System
SBD Network
Equipment
End User Applications
DBCP Technical Workshop 2003

18. DBCP Technical Workshop 2003
SBD Service Overview
An efficient packet-based service for frequent short data transmissions
Service supports 1960 bytes Mobile Originated and 1890 bytes Mobile Terminated
System interfaces:
Device: Extended AT command set
Gateway: - user data is sent in attachments
Pricing plans based on byte usage not time
DBCP Technical Workshop 2003

19. METOCEAN Data Systems Limited
October 9, 2003
METOCEAN’s Iridium Communication Infrastructure
Based on METOCEAN iLink™ Server
Server monitors a port for incoming packets from Iridium buoys
Accepts simultaneous connections from multiple platforms
In effect, each buoy has a direct connection to the database via the Internet
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

20. METOCEAN Data Systems Limited
October 9, 2003
Message Processing
Each buoy maintains a queue of hourly reports, transmitted upon connection to the server
An acknowledgement is sent back only if the data is successfully stored in the database
Upon acknowledgement, the buoy deletes the message from its transmission queue
If the message queue is full, the oldest message is deleted
Programmable parameters allow flexibility in message throughput, data loss prevention and delivery costs
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

21. METOCEAN Data Systems Limited
October 9, 2003
Command Processing
Provided by an outgoing message queue in the database
User submits commands via web page
When connected, the buoy sends periodic command request packets and an acknowledgement after a command is received and executed
Commands are stored in the database
All buoy commands can be executed via the Iridium interface
Very powerful but dangerous tool!
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

22. METOCEAN Data Systems Limited
October 9, 2003
Drifting Buoy Deployment
Hourly data acquisition
Barometer, SST and Submergence Sensors
GPS positioning
Bi-directional communications using the Iridium Satellite Network
Customer Command/Data Interface (WWW)
Enhanced METOCEAN Digital Controller
Modular TMOS Software Architecture
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

23. METOCEAN Data Systems Limited
October 9, 2003
Deployment in Bering Sea
NDBC Buoy 46001
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

24. DBCP Technical Workshop 2003
Buoy Data
DBCP Technical Workshop 2003

25. METOCEAN Data Systems Limited
October 9, 2003
Cost Comparison (US$)
Telemetry Costs
Iridium PPP
SBD
Monthly Service Rate
$30
$21
Daily rate
$3.96
$2.20
Total Tx costs for one year
$1,805
$1,055
Number of messages per day 2 24
Bytes transmitted per message
192 32
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

26. METOCEAN Data Systems Limited
October 9, 2003
Iridium Conclusion
Two-way communications and large bandwidth produce power savings
Iridium message throughput is about 80%
Our database management system is 100%
Allows reconfiguration after deployment
Potential cost savings of 33% over other satellite systems
METOCEAN can offer data services
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium

27. METOCEAN Data Systems Limited
October 9, 2003
Thank You !
DBCP Technical Workshop 2003
BIO Technical Presentation on Iridium