Uplink
At present, the only uplink we have consist in the radio control
transmitter. It is used for flight control in manual and
assisted flight modes, but also for all sort of interactions like
flight mode switching, gain and parameters setting, missions event,
waypoint displacement. This "switch and sliders" exercise is simplified
by the real time feedback on the ground station which can be talked
by the
festival speech synthesizer for single person operation.
This is probably not the most efficient way to communicate with an UAV,
but this is cheap and widely available.
We intend to keep supporting this solution even when we have others
available.
Downlink
As explained in the
controller page, the
data downlink is done in the audio channel of the 2.4GHz video
transmitter. We achieve 4800bps using a pair of cmx469 FSK modem chips
or 1200bps using an airborne cmx and a soundcard-software modem
on the ground.
Radio modems
We are evaluating a networked radio modem solution. These
tiny (10g)
Coronis Wavecards operate in the 868MHz ISM band at 500mW.
Line of sight range are expected up to 5 km with throughput up to
19.2kbps.
-
- v1.2.1 controller board coronis wavecard and huge homemade antenna