Airborne cell carrier aggregation

This Call is a part of the Providence Search & Rescue UAV Project.

Cell carrier aggregation is used in several industries, e.g. to send broadcast quality video from TV cameras. How could this be adapted to the demands of small UAV:s?

For the vast majority of maritime Search & Rescue cases in our Swedish waters we are within cell network coverage. Geting a few hundred feet of the ground will probably help the situation. This makes cell connectivity the most reasonable link both for flight control and for streaming video from the UAV. Control and streaming have different demands on the connectivity, but we believe that aggregation will be equally beneficial for both uses.

Control communications consist of sending commands to the onboard autopilot and receiving telemetry data to confirm that the commands are executed properly. Data from onboard AIS- and ADS-B Transponders as well as other sensors dedicated to sense and avoid is also also included. None of these require a lot of bandwidth but uptime is of paramount importance, so this communication will benefit from the redundancy of using all available carriers.

For additional redundancy it would be interesting to explore further fallbacks such as Iridium, Globalstar, Inmarsat or AIS as proposed in the “AIS Transponder for UAV:s“- project.

The video feed is dependent on higher bandwidth – the more the better to enable high resolution and possibly dual streams including thermal images. Uptime is important but probably not to the degree that using satellite connection will usually make sense.

As for all UAV technology we are looking for robustness, low weight, small size and low power consumption.

If several systems could be integrated into one unit that would be a nice bonus. Such systems might include Autopilot, Video conversion, Gimbal control, AIS– and ADS-B Transponders and Voice over IP-radio.

Links & Inspiration

• Finnish firm Sharpershpe has an in-house solution that looks interesting
• Oppetid.net
• Teradek makes aggregators for broadcast video
• Precision hawk is developing LATAS which includes cell connectivity with satellite fallback