On Sat, Jan 9, 2016 at 2:26 PM, Valent Turkovic <valent@otvorenamreza.org> wrote:
Hi all,
I'm one of people who started www.meshpoint.me - idea is to build open
source wifi router that can be easily deployed in any type of crisis
situations.

I have been setting up wifi networks in crisis situations and I know
that there are no devices that are usable in crisis situations.

Belive it or not but first responders usually aren't network admins :)
So that is why we started developing MeshPoint, wifi device that
anybody can use in crisis situation.

First iteration will use off the shelf components and later we plan
develop our own wifi router board using atheros hardware.

Our current design (as you can see on the web site) uses three TP-LINK
WR842ND (AR9341) boards in 3D printed case.

Interesting. No 5 ghz though? If you're worried about L2 retransmissions that seems like the first thing to solve. The TP-Link dual-band routers are cheap as well and you could probably easily swap out your current boards for dual-band models.
 

Our concern is that this could generate too much interference and
cause too much L2 retransmissions because of co-channel interference.

We are using latest OpenWrt 15.04 Chaos Chalmer and ath9k driver and
would like to know if it is possible to extract metrics that shows
number or L2 retransmissions.
Do mac80211 or ath9k tracks L2 retransmission statistics?

I'm no expert on this but try looking at:

  /sys/kernel/debug/ieee80211/phy0/ath9k/xmit

Some info can be gleaned from:

  http://lxr.free-electrons.com/source/drivers/net/wireless/ath/ath9k/debug.h

Is there anyway to get AR9341 datasheet?

Don't have that one, is AR9331 close enough?

  https://www.openhacks.com/uploadsproductos/ar9331_datasheet.pdf

--
marc/juul