Hi, you can contact Telenax, they buil GPS-IRIDIUM-BLUETOOTH+VHF units, these are simple to configure it and to use them also. you don't need to do field work, only to retrieve the unit when you use drop off or to recapture the animal using VHF.

https://telenax.com/products/tgsat-gps-iridium-satellite-communication-wireless-communication/

Hi Robin, I am assuming that you already have VHF tags in place?

Do you know the range that you are getting from them, or the tag type and weight?

You might want to have a look at www.wildlifedrones.net, can do up to 100 VHF tagged animals, use a drone to get a high point.

Hi RcsMartin, yes, in a Puma, we received data once a day or every other day by iridium satellite, the collar tries to send 10 data rows accumulated, so it all depends on how many gps fixes you have per day and the forest density and weather conditions will affect the iridium conecction. VHF signal got from 1 Km to 7 Km (with a 40 Km LOS transmitter), it depends on forest density, climate conditions and the animals positions.   

Thanks for the link of the drones, they only offer the service, they don't sale the equipment, I'm Colombia, I saw a differente drone in the US, they teach you how you can build your own system, a little expensive.

https://uavrt.nau.edu/

https://uavrt.nau.edu/index.php/docs/vehicle/vehicle-assembly/ 

Yep, seen the work they are doing, spoken to a guy who was across them, for transparency I actually work for wildlife drones, UAV-RT have  a reasonably solid idea.  What animals are you primarity tracking?  What is your terrain like? 

We've moved away from wifi connectivity drone to base station too problematical and not enough range back to base station; we also do multiple tags simultaniously, looking from the inside out, triangulating for location.  I can't really say I get the use of I/Q data, from the little I know about tags the orientation of the tag can have a big impact on what you pick up and I'm assuming would then impact the signal strength, which is going to impact the I/Q data and location details?  I'll talk to our techs at some stage to try to get an idea of how it works.

I can send you the links to the original research papers that lead to our commercialised solution, if you're intersted, we can see why we moved in the direction we did.  The oringinal iteration was trying to utilise machine learning, but so far human interaction gives better results as you can position for best potential line of sight.

The payload can also work off a pole, the high point and flexibility is not as good as a drone, but reduces the cost of a drone.  I heard that there are some restrictions with size of drone in Columbia?

We can do some interesting things with our solution, we can piggy back off the antenna to download GPS data, theoretically using a multiple payloads on towers/poles we can get bearings for animals that could be then be triangulated to location, some processing to do the combination of data that we haven't done yet, but probably the cheapest option for covering a largish area with location.  Depending on the tag tradional towers with omni direction antennas will tell you if the animnal is in an area that could be 70km sqr.

Great to hear from you, you can get me on linked or through the WLD website.