search

morrownr / USB-WiFi

USB WiFi Adapter Information for Linux
2.4k stars 161 forks source link

AWUS036AXML (reception power) #457

Open mentalpabulum opened 2 weeks ago

mentalpabulum commented 2 weeks ago

Hi again @morrownr :)

Got a new adapter and it's another disappointment.

image

Very poor reception power. The AWUS036ACH v2 had much better reception power. Apparently, I'm not the only one with this problem.

There is also a problem with using reaver. Constant timeouts regardless of the AP selected. I think it is related to poor reception. image image

As a solution I see buying an antenna. What kind of antenna can you recommend?

mentalpabulum commented 2 weeks ago

Regarding the reaver, it doesn't seem to be about reception power. This one worked fine.

morrownr commented 2 weeks ago

Hi @mentalpabulum

The AWUS036ACH v2 had much better reception power.

It should. The ACH and ACHM are what Alfa calls Max Power adapters. They have better range than any other adapters that Alfa makes. The ACHM has slightly better range than the ACH but both are excellent if extended range is what you need. So far Alfa has not made a Max Power adapter with a WiFi 6 capable chip.

I have an AXML so I can do some testing if needed. I am not familiar with Reaver. Does it try to use Active Monitor Mode. If so, there is currently a bug with Active Monitor Mode in the mt7921u driver. Regular monitor mode works well. Active Monitor Mode is working well with the Alfa ACHM and ACM. Hopefully that can be fixed soon.

The -3 dB txpwr reading is not accurate. A guy in another thread showed us how to get data and calculate the actual reading and it worked out to around -20 dB on 5 GHz. Not sure why that bug has not been fixed. I have had success with the AXML but I have mostly used it in AP and managed mode. It has been very stable with reasonable range for me. Would I like to see a Max Power version? Sure. Maybe we can get a Max Power version with the WiFi 7 chips.

mentalpabulum commented 2 weeks ago

Does the antenna solve the problem with power? Or is there some kind of amplifier inside that determines the range?

Does it try to use Active Monitor Mode.

It's a pixie dust attack, it doesn't use active monitor as far as I know.

morrownr commented 2 weeks ago

Or is there some kind of amplifier inside that determines the range?

There is an amp inside. There are multiple things that affect range:

  1. The limitation of power output which is determined by law. We can't do anything about this.
  2. The quality of antennas and amp. This is how the ACHM and ACH do it.
  3. Other factors that affect radio waves like obstructions, interference and humidity.

I have a LOT of adapters and am willing to try to help you explore the problem... if you are not in a big hurry. I can test with the AXML and then other adapters to see what we get. How do I install this Reaver and use it?

mentalpabulum commented 2 weeks ago

I have a LOT of adapters and am willing to try to help you explore the problem...

Did you use third party antennas? I'm interested in the range issue, how to maximize it with the current adapter.

if you are not in a big hurry. I can test with the AXML and then other adapters to see what we get. How do I install this Reaver and use it?

Clone and compile Pick AP with WPS: airodump-ng wlan0mon --manufacturer --wps --uptime Run: ./reaver -i wlan0mon -b "XX:XX:XX:XX:XX:XX" -vv

morrownr commented 2 weeks ago

Did you use third party antennas?

No. However, I just did a quick test: I used the antennas from my AXML on my EDUP EP-AX1672. Both are based on the m7921au chip and have removable antennas. The Edup just happened to be connected and handy to do a quick test.

Signal level as shown by wavemon:

With Edup antennas - -38 dBm With Alfa antennas - -35 dBm

So, the Alfa antennas improved the signal level by 3 dBm. My additional thoughts would be that you could improve range with directional antennas or a beer can/aluminum foil. There are a lot of guides on the net for using beer/soda cans or aluminum foil so you could investigate that as it could be a good low cost solution.

Thanks for the instructions. I need to be out of the office for most of the rest of the day but will look at Reaver as able.

mentalpabulum commented 2 weeks ago

Check this: antenna.pdf

morrownr commented 1 week ago

That file has some cool ideas. It would appear you are primarily interested in the 2.4 GHz band. One thing that needs to be determined if you decide to build an antenna is how the 2.4 band is supported... one antenna? which one? internal? We would need to open the axml up to see what is the setup if we can figure it out. I'll see what I can determine as I get time. I may be off the internet for the next 2 or 3 days due to a medical issue I need to take care of.

If the axml is only using one of its antennas for 2.4, then it would be easy to change out for something you build or there are directional antennas for sale. Alfa makes them.

Early this morning I did a quick test with my axml to what kind of range I was seeing. The test was from about 15 meters from the AP through 3 walls on 5 GHz. I was seeing a signal level of ~-60 which is pretty good for the situation I put it in. If I had remembered that you were working 2.4 GHz then I would have tested it and I can as I get time. Does the axml have the range of the achm? No. However it is not designed to have that kind of range. Maybe someday we will see a Max Power adapter with WiFi 6 or 7 but not yet.