RSSI direction finding

slomobile · 2021-12-07T19:35:44.351Z

I would like to do this on a GL-AR300M16-EXT; except that I would like to have the left LED brightness correspond to left antenna received signal strength, and right LED to right antenna.

If I put a Λ shaped plate between the antennae, it would attenuate signals from behind, and from the opposite side. I would have a WiFi direction finder. Turn in the direction of the brighter LED until both are equal brightness. The Λ is pointing in the direction of the signal.

Unfortunately rssi comes from wlan0 which (I think) represents the combined signal strength of both antennae. Is there any way to break out individual values?

Failing that, is there any other hardware that can be used to accomplish this?

Perhaps mounting 2 independent WiFi radios (GL-AR150) next to each other?
However, whenever I do that they interfere with each other causing them to alternately drop the connection.

Perhaps the UARTS could be connected together to schedule transmissions and work cooperatively?

Maybe 2 GL-USB150 connected to the same host or USB hub, could be synchronized by software on the host.

Not sure which approach is best.

Would love to hear ideas.

Boesesblut · 2021-12-09T06:08:35.955Z

I think thère will be difficult to use STA mode configured SoC devices such as AR150 to monitor. What you are calling for is SDR realm like a HackRF and YardstickOne from Great Scott Gadgets
LimeSDR is like a rpi i think
or Ettus B200/300 USRP from ettus.com. The latter are pricey but finest quality and service in the industry. Then you can use GNU Radio and other SDR programs
DragonOS focal by cemaexcuter is Ubuntu based SDR focus distro I use.

alzhao · 2021-12-13T09:29:43.854Z

Maybe need to get a directional antenna. When rotate the directional antenna, check the RSSI and use LEDs to indicate strength.

Just some idea. Not very reliastic. Should have more professional raido equipment for these applications.

slomobile · 2021-12-13T10:25:04.006Z

Thanks. A HackRF one is available to monitor all the nodes at once, at least until the mesh expands beyond its range. Each node is a mini router mounted to a mobile robot . The purpose is an inexpensive rapidly deployable emergency network. Deploy from a single location and the mesh expands in a target direction until signal falls below a threshold. We need some indicator of direction to neighboring nodes to steer the robots in case GPS reception is compromised. A 12 sector 30deg indication is sufficient. We can spin the whole robot to determine the direction with strongest signal. But that takes time and power we’d rather not spend. A rotator is another expensive add on. A continuous differential rssi would be handy for guiding the robots toward optimum signal.