Emlid Store Blog Docs
Contacts

EDGE AWUS036ACH Bit rate

Navio / Edge Raspbian
#1

Hello,

I am using edge firmware v1.5 and Ardupilot Multirotor v3.5.5.

I am getting low range with my drone, losing connection at arround 300m from base at 120m height. I guess antena placement on both the drone and the ground station are okay, RF enviroment is okay (I tried different locattions).

I have checked that the onboard Tx is indeed at 30dBm power, both according to QGroundControl setup and SSH acess, so now, I think that If reduce the bit rate I could extend the range.

However, as you could see at the following print, I couldn’t:

image
image620×218 28.9 KB

How could I check the current bit rate? How could I change it?

Best Regards,
Gabriel

#3

Hi Gabriel,

Thanks for your patience!

The range you’re achieving looks rather short. Please share the photos of your setup so that we can check if everything is configured correctly. Additionally, it’d be great to see the DataFlash logs: they’ll allow us to review different parameters that might affect the range.

#5

Hello,

See attached a few photos of my setup.

The datalink antenas are in down vertical position on those photos, but for the flight they were in inverted V position. On the ground, the datalink were placed on the laptop lid, V-position, as recommended by the official docs. Clear line of sight between drone and ground station at all times.

In this link you can download two logs:

20201217_105915
20201217_1059154032×1960 3.4 MB
20201217_105923
20201217_1059234032×1960 3.21 MB
20201217_105929
20201217_1059294032×1960 3.55 MB
20201217_105935
20201217_1059354032×1960 3.59 MB
20201217_105943
20201217_1059434032×1960 3.8 MB

1 Like
#7

Hi Gabriel,

Thanks for the data! We’ll take a closer look at it and I’ll be in touch with the results.

#8

@gm2gabriel
You could check the connection speed/bitrate from/to your copter on your GCS laptop. Both Linux and Windows should show it in the connection properties. If I remember correctly the Emlid Edge sets it to 802.11a speed (54Mbit/s). The lowest bitrate 802.11a supports is 6Mbit/s, so setting it to 1Mbit/s will not work in any case. Any setting always sets the nominal bitrate. The useable bitrate will be lower than this.
I would also mount the wifi adapter vertical, to bring the antennas further below the copter. The active part of the antenna is only about half of the outer pipe. I would also make a bracing mount that fixes the antennas to the copter frame or the wifi modules case. The forces on the antennas from vibrations and wind might damage the wifi modules PCB.

#9

Thanks for the advice! I will try to follow your recomendations concerning the wifi adapter and antennas, I will also try to verify the connection speed and lower it, if possible.

For a sanity check, I have ordered a new couple of AWUS036ACH adapters.