Optimal settings for sik radios

Does anyone have any optimal sik radio settings (air speed, baud rate, window size, etc) that they use to communicate ROS or mavlink messages over sik radios and would be willing to share?

I imagine that across brands such as RFD or Holybro the parameters would be fairly similar? please let me know if that is incorrect.

How exactly do you want to connect to ros?
Normally any default SIK baudrate is 57600 and mostly is default on the PX4 Telem ports.
But if you want to connect ros via Telem than you have to define the the USB-Port (like ttyUSB0) and the baud rate in the ros connection files. As far as I now…

I am looking at two ways.

Method 1. Connect my SIK radio directly to the flight controller and communicate those topics directly to a linux computer on the ground with ROS.

Method 2: On board computer is connected to the flight controller and is seeing the ROS topics. The onboard computer then sends ROS messages back to the ground computer using a SIK radio.

However I am struggling with limited range, but I am only sending small ROS messages at slower rates compared to the MAVLINK messages that are being sent and recieved by my separate QGC computer also connected to the flight controller via SIK radio.

Have yuo tried instead of using SIK radio, some ethernet links or wifi? In ros you can configure in the .launch files what ttyUSB and as well baud rate (for telem) or ttyACM what flight controller you want to gather from and where to send it. If you have a good radio you can still send good range with telem. otherwise use wither is faster and has higher bandwith

The low range/bandwidth SiK radios work fine for the default PX4 MAVLink telemetry streams. You should also be OK if using ROS and MAVROS for basic goto style control and telemetry since that translates to MAVLink.
If you’re doing anything high rate, you will need a radio with more bandwidth. For example, streaming setpoints at high rate for some kind of computer vision application.

Most of the discussion here are about using ROS2 to control the flight stack by an onboard companion computer. There you have a high rate channel. Not so common to hear about ROS2 as a ground station protocol.

Interesting. My messages do not need to be high rate ~10 Hz and they are small in size (3 variables of 4 bytes each). My thought was to keep everything ROS and communicate from a ROS base station computer to a ROS onboard computer via a SiK radio. @hamishwillee , in your opinion am I going down a rabbit hole not worth traveling?

I am out of wifi range. I figured since my QGC Sik radio to the drone was in range my ROS Sik radio would also theoritically be in range if I kept my communications down to a minimum. Can you elaborate what you meant by

In ros you can configure in the .launch files what ttyUSB and as well baud rate (for telem) or ttyACM what flight controller you want to gather from and where to send it.

in your opinion am I going down a rabbit hole not worth traveling?

It’s mostly a matter of bandwidth. If you have few messages at low rate then it is worth exploring at least when using MAVROS. If you are using ROS2 I am not sure what the “overheads” are.