1. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 ARGOS DOWNLINK Christian Ortega, CLS Bill Woodward, Service Argos

2. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 SUMMARY Current Argos System Downlink – overview Downlink – overview Downlink Functions/Services Downlink Functions/Services Create a Request to Send a MSG Create a Request to Send a MSG Transmission Modes Transmission Modes PMT - introduction PMT - introduction

3. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 THE CURRENT ARGOS SYSTEM  Satellite-based data collection and location system  Short message transmission  Unidirectional system  Random access system ( no communication protocol)  Simple, cheap and reliable  But,…

4. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 …Users cannot communicate with their platform once it is deployed

5. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 The ARGOS Space segment NOAA 14NOAA 15 NOAA- 16 Argos 1 Argos 2 ADEOS - II Argos 2+ NOAA - 17 Argos 2

6. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 Evolution of the constellation

7. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003

8. HOW ARGOS WORKS NOW  Random transmission ( most of the time)  No acknowledgement if satellite receives a good message Message 1 09:00 Message 2 09:01 Message 3 09:02 Message 4 09:03 lost

9. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 ARGOS DOWNLINK- Overview Send Short Messages to PMT Equipped Platforms  Send Short Messages to PMT Equipped Platforms Centralized Msg Management - DMMC  Centralized Msg Management - DMMC Global Coverage  Global Coverage

10. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 Four Main Downlink Functions/Services Downlink Signal/Satellite Detection 1. Downlink Signal/Satellite Detection Global Broadcast of Argos System Related Msgs 2. Global Broadcast of Argos System Related Msgs User Defined Msgs for Remote Control of Platforms 3. User Defined Msgs for Remote Control of Platforms Interactive Data Collection 4. Interactive Data Collection

11. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 Consequences for users u Transmit more data with acknowledgement of satellite (uplink interactive mode) u Modify setting of parameters inside platforms via the downlink (ex: diving depth for floats, modification of a sampling period on sensors, modification of sensor acquisition strategies, start or stop acquisition,…) u Save energy: possibility to transmit only on satellite passes u The Receiver will be considered as a slave plug and play module like any sensor

12. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 The receiver detects the satellite signal DOWNLINK MESSAGING SERVICES (1) Signal/Satellite Detection

13. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 Global Broadcasting of Argos System Messages ( for satellite pass prediction and selection) Argos constellation status UTC time Argos satellite orbital parameters DOWNLINK MESSAGING SERVICES (2) Broadcast service is available to all PMTs!

14. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 DOWNLINK MESSAGING SERVICES (3) DMMC User or User Office 1) Message reception 2) Acknowledgement message sending MB selection (Japan, France,Sweden, Alaska) MB APC Acknowledgements Directives Remote loading context Requests Sending Messages – Platform Control

15. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 INTERACTIVE DATA COLLECTION DOWNLINK MESSAGING SERVICES (4)  Satellite Acknowledges Receipt of Error - Free Messages Eliminates Need to Send Repetitive Messages Blindly  Eliminates Need to Send Repetitive Messages Blindly  Significantly Increases Data Throughput During a Satellite Pass  User Must Request This – Not Automatic

16. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 Interactive Data Collection

17. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 Create a request to Send a Message To Whom:a PMT / a group of PMTs  To Whom:a PMT / a group of PMTs When:at the earliest date/ at a given date  When:at the earliest date/ at a given date single sending / periodical sending Transmission Mode :triggered / programmed  Transmission Mode :triggered / programmed Transmission period : from 1 satellite pass to 8 days  Transmission period : from 1 satellite pass to 8 days Message type:Predefined / user-defined message  Message type:Predefined / user-defined message

18. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 Triggered Mode Triggered Mode DMMC Request creation The PMT receives the downlink message and acknowledges Once the satellite receives a message sent by the PMT, it transmits the downlink message PMT is transmittingAPC Acknowledgements MB

19. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 Programmed Mode Programmed Mode DMMC Request creation The PMT receives the downlink message and acknowledges The satellite sends the downlink message APC Acknowledgements MB

20. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 Satellite PTTPMT One-wayTwo-way PMT vs PTT

21. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 PTT Logical Unit Sensors Platform Transmitter Terminal: PTT

22. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 Receiver PTT Logical Unit Sensors Platform Messaging Transceiver: PMT

23. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 PMT Development  Bathy Systems, Inc.  Uses Receiver Built by IESM (France)  Prototypes Available in Late 2003  Initial Applications : balloons, drifters, floats

24. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 Prototype PMT Approx. 6 in Approx. 6 in.

25. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 BENEFITS OF USING ARGOS 2-WAY

26. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003  Transmit More Data per Satellite Pass  Modify Parameter Settings on Your Platform  Transmit Only on Satellite Pass – Save Power

27. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 USING INTERACTIVE MODE  RANDOM ACCESS SYSTEM  No Ground to Sky Protocol  Improve Good Receipt by repeat Xmissions (same msg sent multiple times)  DIFFERENT WITH ARGOS 2-WAY  Error-free msg Receipt is acknowledged  Repeat Transmissions are minimized/eliminated  RESULT = MORE MSGS (DATA per PASS)

28. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 USING INTERACTIVE MODE FLOAT EXAMPLE – APEX (Webb Research) Current “Typical” Transmission Strategy Current “Typical” Transmission Strategy  4 2/3 Data Triplets (P,T,S) per Argos Msg  15 Msgs are Req’d to Send a Profile of 71 Levels  Each Msg is Sent Multiple Times at a 45 sec. Rep. Rate  Required Surface Time is 3 to 10+Hours

29. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 USING INTERACTIVE MODE FLOAT EXAMPLE – APEX (continued) Possible Strategy with Argos 2-Way Possible Strategy with Argos 2-Way  4 2/3 Data Triplets (P,T,S) per Argos Msg  15 Msgs are Req’d to Send a Profile of 71 Levels  Each Msg is Sent until ACK is Received  Use a 30 sec. Rep. Rate, Send 20 msgs in a 10 min. Sat. Pass 10 Hours 10 Mins

30. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 USING INTERACTIVE MODE FLOAT EXAMPLE – APEX (continued)  RESULT: AN ENTIRE PROFILE CAN BE SENT IN A SINGLE SATELLITE PASS!

31. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003  Parking depth for a float, control of diving cycles, sampling on sensors,...  Modify the transmission strategy (e.g., transmit more data when necessary) USING USER DEFINED MESSAGES REMOTELY MODIFY PLATFORM SETTINGS REMOTELY MODIFY PLATFORM SETTINGS

32. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 Time (UTC) Thu Sep 25 17:52:57 2003 1 (ADEOS II) AOS Thu Sep 25 18:03:49 2003 in 00:10:52 (00:16:32) Max.El 45 2 ( NOAA 12) AOS Thu Sep 25 22:56:57 2003 in 05:04:00 (00:14:56) Max.El 20 3 ( NOAA 11) AOS Thu Sep 25 19:16:17 2003 in 01:23:20 (00:16:38) Max.El 68 4 ( NOAA 14) AOS Fri Sep 26 00:18:50 2003 in 06:25:53 (00:03:00) Max.El 00 5 ( NOAA 15) AOS Thu Sep 25 23:54:34 2003 in 06:01:37 (00:06:22) Max.El 01 6 ( NOAA 16) AOS Thu Sep 25 20:02:34 2003 in 02:09:37 (00:13:56) Max.El 13 7 ( NOAA 17) AOS Thu Sep 25 18:32:02 2003 in 00:39:05 (00:17:06) Max.El 71 PASS PREDICTION DATA

33. DBCP Technical Workshop – Angra dos Reis, Brazil – October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

34. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 PMT> Thu Sep 25 18:03:51 2003 Satellite: 1 (ADEOS II) is overhead Duration: 00:16:32 Max. El: 45 Sending Request for Interactive RECEIVED: 23CCB6A104000123456789ABCDEFF67D *Interactive Request timed out Sending Request for Interactive *Interactive Request timed out Sending Request for Interactive RECEIVED: 23CCB6A102AE8D01570B *Interactive Session Go-Ahead Message BEGIN INTERACTIVE SESSION

35. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 Send Message IRP 00 -> FFFE2FF23CCB6AA9480032323232323232323232323232323232323232323232323232323232 RECEIVED: 23CCB6A101A94825C4 Acknowledgement of an Interactive PMT uplink message within a session. ACK on Message £0 Send Message IRP 01 -> FFFE2FF23CCB6A59AE0132323232323232323232323232323232323232323232323232323232 Send Message IRP 02 -> FFFE2FF23CCB6A58A50232323232323232323232323232323232323232323232323232323232 RECEIVED: 23CCB6A10158A529B7 Acknowledgement of an Interactive PMT uplink message within a session. ACK on Message £2 Send Message IRP 03 -> FFFE2FF23CCB6AA8430332323232323232323232323232323232323232323232323232323232 Send Message IRP 04 -> FFFE2FF23CCB6A5AB30432323232323232323232323232323232323232323232323232323232 RECEIVED: 23CCB6A1015AB33D22 Acknowledgement of an Interactive PMT uplink message within a session. ACK on Message £4 Send Message IRP 05 -> FFFE2FF23CCB6AAA550532323232323232323232323232323232323232323232323232323232 RECEIVED: 23CCB6A101AA55B30B Acknowledgement of an Interactive PMT uplink message within a session. ACK on Message £5 Send Message IRP 06 -> FFFE2FF23CCB6AAB5E0632323232323232323232323232323232323232323232323232323232 RECEIVED: 23CCB6A101AB5E3151 Acknowledgement of an Interactive PMT uplink message within a session. ACK on Message £6 Send Message IRP 07 -> FFFE2FF23CCB6A5BB80732323232323232323232323232323232323232323232323232323232 Send Message IRP 08 -> FFFE2FF23CCB6A5E9F0832323232323232323232323232323232323232323232323232323232 RECEIVED: 23CCB6A1015E9F1408 Acknowledgement of an Interactive PMT uplink message within a session. ACK on Message £8

36. DBCP Technical Workshop – Angra dos Reis, Brazil – October 20, 2003 PMT> PMT>stats Bytes Sent : 504 Bytes in Message: 504 Percent Complete: 100 SUMMARY OF SESSION