Forum

Hello All,
I have recently been part of a project trying to extend the maximum range that a wireless client can connect. We did this testing in both 2.4GHZ and 5GHZ. Testing went well in 2.4; however we could not get more than 10 feet with the 5GHZ range before packets started being dropped and we receive a death reason 3 error. We are using Ubuntu 10.04 trying to connect to a Cisco aironet 1130ag.

I have updated the drivers for the Gold Alfa Card AWUS051NH I am using, including following the manufacturer's installation guide.
I also tried using a PCMCIA slot Ubiquiti a/b/g SRC300 card with updated drivers. Still nothing.

What am I missing that I get great range in 2.4GHZ and awful range in 5GHZ?

Thank you.

Um. Have you verified your environment is ok? That u know of nothing else transmitting on 5ghz.? Is your AP transmitting on full power? What's your signal strength at 10ft?

Just off the top of my head

Deauth code 3 is because the STA is leaving or has left the ESS. I would check the client configs. Can you post your wpa_supplicant.conf and possibly what driver you are using ie madwifi for the SRC300, I'm guessing. Could be a key caching mismatch assuming the encryption suite is different between the 5GHz and 2.4GHz. What transmit power are you using on the 5GHz AP radio?

As far as the environment goes, its a beach front bridging over water. Clear environment, only one nearby tower AP.

Ideally the access point transmits 50mw, with no support for external antennas.
Also we arent using encryption for the access point, so that shouldnt be an issue... Also using terminal and GUI for connection...

I will have to double check the drivers tonight. Would drivers on the same card have a different effect on different frequencies? That could be whats going on with the signal strength received from the client. It hops at 10 feet from -40 to 90... Ouch.

I don't know how water affects 5GHz signals, but 50 mW (17 dBm) is not especially a lot of power.

It sounds like you just don't have the range. Is this over a marina? Could there be boat-based AP's interferring with your signal? Marine radar?

Aaah, I did not consider radar or anything. This is in a port facility with ships coming and going, though they usually dont radiate equipment while in port... It could be the actual port's radar. (not sure what freq ship/shore radar runs through) I only did a wifi site survey - I don't have a spec-an...

Also considering putting in an order for higher powered outdoor access points with external antenna support.

Consider also that Ralink does not have the best Linux support. There is debate over the "freeness" of requiring closed-source firmware for the chip, and Ralink does not maintain the driver for the open-source community. Not saying this is the source of all your problems, but it may be a factor.

How much difference you are seeing between 2.4Ghz & 5Ghz?
Higher the frequency higher will the attenuation. Again Fresnel Zone depends on the Frequency. Also higher frequencies have less penetration through the objects. Basically the 2.4Ghz band will have higher range than 5Ghz.

You might want to check the retransmission rate. This can be caused by Multipath(Beach areas have high humidity. The rf-wave might get scattered & leads to the Multipath)

Since you are using the AP in the outdoor environment its better to use AP with the antennas.