So the Flight Management System is the Ground
Segment including the GCS then?
All your other answers make sense. Thanks Gautier.
As for our Wi-Fi setup Hector; this link is
designed for in-flight transfer of still images from the plane
to the ground. We use XTend radios for our autopilot
telemetry. However, I've been working on support for multiple,
redundant links (http://paparazzi.enac.fr/wiki/Redundant_comms
and want to fly using this system. I'm hoping to have it
working for demonstration or flight at the AUVSI SUAS
competition at the end of this week. But I might not succeed.
So the Wi-Fi telemetry doesn't need to be reliable. Having
We use two Engenious Routers 802.11 g routers at
2.4 GHz. We've got a parabolic antenna at the ground station
that someone points at the plane. We've tested with the
airplane on the ground up to 3 Km with a throughput
(bandwidth) of around 1 MB/s. At 6 Km, we were able to see the
access point, but not connect to it reliably. In the lab, we
got throughput up to around 2.5 MB/s.
During flights, we've had some loss of connection
when the plane was within 500 m, but we think that this was
due to the antenna pointer person not doing a good job (as in
90 degrees off). Nevertheless, we're far from considering this
link reliable - we need lots more testing.
For RC we use a 2.4 GHz Spectrum DSMX transmitter.
During the above range testing, we tested extensively for
interference and didn't find any. At the 6 Km, the RC worked
great even when the Wi-Fi was transmitting UDP packets at a
full rate. The only interference we noticed was when the RC
transmitter was positioned only a few meters in front of the
We've also carefully designed our antenna
placement in the plane to try and make the antennas invisible
to each other by making them co-linear or orthogonal.
The biggest RC interference issue we had was when we set up an
access point at the ground station for other purposes. It was
set to auto select a channel (and the plane's router was on a
fixed frequency). But the new access point picked the exact
same channel and blocked the signal. I suspect that it
couldn't see the airplane's access point since it didn't have
the parabolic antenna. We know to be very careful about this
I've got lots more details if you'd like - I wrote
a whole report on this. I should probably make that publicly
available somewhere. Let me know if you're interested and I'll
put in the effort.