How does it work

I am sitting now at home in Roskilde and follow our geese. But how does it work that our geese are far from here but I can still know where they are?
Our tags send signal through GPS antenna to the satellites orbiting around the Earth. Obtaining GPS positions are done exactly the same way as getting a position when we drive a car with satnav.

The GPS positions are stored in the memory of the tag and than send through ARGOS system to the processing center. The ARGOS system has 6 satellites which collect the data. You can read about details at ARGOS website. I can than log in to the ARGOS and download the data. We can pre-program the tags and decide how often we want to have GPS positions collected and how often send to the ARGOS system


In 2011 we bought 6 tags from Microwave Telemetry. Each tag weighs 45g and has GPS and ARGOS system antenna and also solar battery. Therefore we don't have to worry about the battery capacity because this battery can be recharged every time there are suitable sun conditions.
Below is the picture of the tag used in 2011. The long antenna is to communicate with Argos and the antenna in the back (this flat, square part of the tag) is to obtain GPS positions.

In 2012, we asked another company, North Star, to make 5 tags for us. The technology is very similar

Here is going to be uploaded a great movie/interview with Tony Fox where we will explained how the geese were caught and how did we deploy the satellites. But this is still future since I have no time:)