Argos Satellite Tracking - User Guide

Old manual but the principals apply.

The following application is written in Powerhouse.

Please submit any application development enquiries using the feedback form.


The application, back to Contents

The ARGOS application allows users to manipulate ARGOS PTT data and produce maps and listings.

Check for details on this local ARGOS system document or go to the ARGOS home page. You may wish to see the Wildlife Telemetry Clearinghouse for related applications.

To start the application, typing ARGOS once logged onto Marvin and the first screen looks similar to this. There may be slight differences as the application evolves ahead of this manual.

To activate any of the options, just type the number on the left in the action box.

Screen 10 Programs and batch reporting allows the user to cluster multiple PTT profiles together as one logical unit that can be reported via one action. The following example displays the program 973 and lines 4 to 13 display several PTTs and some of the data from the profile.

Investigator and details are for storing the chief invstigator of the program and details of its purpose. Please enter these if missing so the maintainer of the application can sort out any problems with particular ptts/programs.

Batch name is a name that the user can assign to this program and is used by the VAX to name the batch job that gets created. The options at the bottom allow the user to control this job.

Creating a profile of a PTT, back to Contents

Screen 11 allows the user to create a profile of a PTT that can be used repeatedly to plot maps and/or produce a list of positions and distances from specified reference points.

A profile is a set of parameters that control the extraction of data from the Argos data sets and then the mapping of that subset of data.

Each profile has a unique computer generated number starting from 1. By using this to identify the profile, instead of the PTT number, you can change the PTT number without casuing problems with profiles linked to multi-profile plots. Screen 11 has multiple keys. It will ask for a record via

The above example requires data about PTT number 1398 from 13-Nov-1994 to 30-Nov-1994 excluding data with quality below 1 and using Edmondson Point in the Ross Sea as the reference point. A map is constructed using the set map limits and not the bounds of the data. When first plotting some data, it is useful just to let the data control the map plot bounds so that all data is visible. After selecting some suitable map limits then set the flag Autoscale map to N.

Once you have a profile then use the following commands

Some parameters and how they control the data.

Data selection

Mapping control

Comments on the listing

At the top of the listing is the date range, profile name and comments from the profile, the miminum quality of fixes used and the start reference point.

It contains the following columns

Creating a plot from multiple profiles, back to Contents

This screen allows the user to associate several profiles together and then plot them on a common map.

Inputs are:

To enter a profile, goto to the PTT field and use "." to see a list of profiles. This new screen will ask for either a PTT number or a simple return will then ask for a reference location (easy then to list all profiles at a deployment site). Select the required profile by typing the id number in the action box. This profile and some details will be displayed back on the multi-profile screen.

Finally once a profile is created, do either of the following

Reference Points, back to Contents

Screen 12 is a maintenance table of reference points and locations that can be used to calculate distance and bearings from as the PTT transmitter wanders about. A three letter code is used to identify the location. Use a sensible code that is easy to remember. Note some locations are ships as this table is used by many other applications so please dont muck it up indescriminately.

If relevant, enter positions as decimal degrees (negative for southern latitudes or western longitudes) and decimal minutes.

Maps, back to Contents

Screen 13 is maintenance table of known map filenames and associated descriptions that the user can select from for plotting.

Map name is the actual VMS filename. The above examples live in the directory pointed to by the logical map:. These maps have a specfic data format. Contact the author for more details.

Filenames ending with GEO are recent and better resolution maps. All new map files will eventually replace the older *.DAT files.

Getting data direct from Argos, back to Contents

Options 20 and 21 allow direct connection to an ARGOS computer and require a valid ARGOS computer Username and password. The connection to Melbourne needs Telnet whilst the connection to France requires logging into a VAX that has PSI software for access to Austpac. At the moment only BIGEAR has this facility. Connecting to Melbourne should be sufficient for most needs.

Both these options create a log file of the session with the Argos computers, and if the appropriate commands were used, the log file will contain the PTT data amongst other text. See the last section for details of some Argos commands.

Batch downloading of data, back to Contents

Each day, in the wee small hours, a batch job connects to the Argos computer in Melbourne and downloads the last two days data. After processing and loading into the local Argos data files, a summary message is created and mailed to the mail list ARGOS_USERS. An example of one of these messages is

 Statistics from loading recent PTT data
 Records read                1191
 New records added            833
 Old records updated          357

Program    PTT  Passes  Dates                     Notes
    366   1171      41  1996 01 10 to 1996 01 11
          1172      46  1996 01 10 to 1996 01 11
          1173      37  1996 01 10 to 1996 01 11
    973   1398      21  1996 01 10 to 1996 01 11
         21055      30  1996 01 10 to 1996 01 11
         23358      19  1996 01 10 to 1996 01 11
         23360      19  1996 01 10 to 1996 01 11
         25985      21  1996 01 10 to 1996 01 11
         25986       6  1996 01 10 to 1996 01 10
         25987      33  1996 01 10 to 1996 01 11
         25989      34  1996 01 10 to 1996 01 11
         27169       5  1996 01 11 to 1996 01 11  No calibration file for PTT
   1155   4471      39  1996 01 10 to 1996 01 11
          4473      37  1996 01 10 to 1996 01 11

At the top is the total number of records contained in the download, the number of records that were updated and the number of new ones. Since the load occurs every day and we get two days data, the number of updated records is about the same as the number of new records. A PTT will create at most 28 messages per day, ie a message per pass.

Further down is the PTT and its program along with the number of messages processed. If a calibration file is missing, it is noted in the last column. This file is important as it contains the dates when the PTT is valid along with conversion factors for converting sensor data to real units. For tracking purposes, the conversion factors are not important.

Note that by the time you query the database, the data is between 4 and 24 hours old. If you wish to get the most recent positions (for example retrieving an incoming PTT) then you will need to login directly to the Argos computers.

The Argos computers retain only the last 4 days data online. After that it is purged. About two to three weeks after the end of a month, the Division receives a tape containing the complete records from the last month. It is a superset of the daily downloads. All data in the database is replaced with this set of data. You know when a new set of data has been added when you receive a mesage like...

Note that a repeated analysis of the last months data may give rise to a different output. After three months, Argos remove all data and expect the host institute to retain the data. The current online database at the Division goes back to 1991 with tapes going back to 198?. There are notes on how the process for downloading ARGOS data.

Putting maps/lists on the web, back to Contents

The flag 'Put on Web' can be user set to 'Y' (for yes) so that the data from that profile can be automatically placed on the web after the normal daily download. Note that the maps are not fantastic but it does allow a user to quickly check the data without running the ARGOS program.