Using Fast DDS over RF datalink with intermittent connectivity (UAV use case)

[drosant]

Hi all,

I’m currently working on a UAV system that uses a secondary RF datalink to communicate between the drone and a ground segment. The UAV flies up to 35 km away, and the link offers around 2 Mbps of bandwidth, but it can suffer from occasional disconnections and moderate packet loss due to environmental factors and distance.

I’m not using ROS 2, but I know Fast DDS is widely used there and I’d like to benefit from your experience.

I’m trying to evaluate whether Fast DDS is a good fit for this kind of RF environment, or whether its traffic (heartbeats, discovery, reliability mechanisms) could become problematic when:
• The connection is not always stable
• There are short outages
• There’s no guaranteed delivery
• Bandwidth and latency are variable

The datalink is based on a proprietary long-range RF module (not Wi-Fi, not Ethernet), and currently we use a custom lightweight protocol for status/control, but I’m exploring if DDS could help standardize communication.

Has anyone tried using Fast DDS in similar RF-based or airborne scenarios?

Any tips for QoS tuning, discovery management or link-layer tricks (e.g. tunneling DDS over TCP or VPN, etc.) would be greatly appreciated.

Thanks in advance!
Diego

[rsanchez15]

Hi @drosant

Fast DDS can pack a “low-bandwidth transport” profile and plenty of adjustable QoS settings, letting it work over unreliable, 2 Mbps RF links without flooding the channel or losing data when the connection breaks. We’ve already used Fast DDS in similar low-bandwidth RF communication use cases.

That said, every RF chain has its own requirements (modem MTU, outage length, retry strategy, etc.). As this is a complex use case, please write an email to [email protected] explaining the details of your architecture. Our team would be able to elaborate on a tailored profile and walk you through the next steps.