[OpenWrt-Devel] QCA9994 outdoor 13km link

Wed Sep 25 16:51:24 EDT 2019

Hi, 

In the beginning i was using 2 dishes on each side. They are ubiquiti 2x2 dual polarized dishes and i connected the chains of station in the same way as AP and i still had issues. After that i thought the problem might be because this card uses mimo multipath and AP ch0 should talk with station ch  0 1 2 3. With 2x2 dishes that's not possible because 

DISH 1 

CH0 -H 

CH1 -V 

CH2 -H 

CH3 -V 

The station pigtails were connected in the same way as AP.  

In this configuration AP ch0 whish is Horizontal can talk only with station ch0 and ch2. 

So i decided to go with Jiroues single polarity dishes on each side. You think that single polarity might be the problem but why it doesn't cause problems in routers when there are 4 omni antennas and still you can get datarates 866Mbps by phone(my phone is 2x2). The testing distance now is 5km but the distance where they will be installed is 13km. We also have dozens of ubiquiti and mikrotik links and 13km it's not a big deal.  

Today also i noticed something strange. The AP was openwrt and station was ddwrt and i got  433/866 and after changing the station to openwrt the datarates got worse. Ddwrt wasn't good either. It had datarates problem.  

Can it be something wrong with firmware antenna configuration? Why it shows only two antennas iw phy phy0 info? 

Thank you 

On Wed, Sep 25, 2019 at 6:34 PM +0200, "Koen Vandeputte" <koen.vandeputte at ncentric.com> wrote:

On 25.09.19 17:14, support at maxnet.al wrote:
> This is long distance, 5km with 4 dishes on each side. They are all 
> vertical and all chains have signal range -60 to -65.
>
> I don't have omni antennas. Is there a problem that i am using dishes?
>
>
I run dozens of long-range devices, and I'm seeing 2 issues in your setup:

1)

- Ack-to issues kick in starting from roughly 1000m.  When you cannot 
alter ack_to (coverage class), you will notice severe performance issues 
above 1000m

2)

- Using identical polarization on all chains is an absolute performance 
killer.

I have 2 devices,  both 2x2 802.11n, HT40 SGI, which are only 150m 
apart, all chains V polarized.

When running speedtests, inspecting ath9k rate control shows it is stuck 
at the max speed for 1 chain (iso 2)

In my case it means the absolute link rate is 130Mbit iso 270 in this 
configuration.

I can imagine using 4 chains will even reduce performance a lot more.

You should really try to use use H + V+ (-45) + (+45).

Also, ensure radio's at both sides have the chains on identical 
polarization. (Chain0 - V,  Chain1 - H, ..)

Regards,

Koen

>
> On Wed, Sep 25, 2019 at 5:11 PM +0200, "Ben Greear" 
> > wrote:
>
>     Is this short distance or long?
>
>     Please try short distance with omni antenna first to make sure you are not hitting the delayed-ack issue
>     or problems with your antenna.
>
>     Change your antenna orientation so that they point in different directions.
>
>     Thanks,
>     Ben
>
>     On 9/25/19 6:49 AM, support at maxnet.al wrote:
>     > Hello,
>     > 
>     > Today i managed to connect the station wds at 80MHz channel. Signal is -56 and i have very low datarates. I have attached a photo.
>     > 
>     >   When station was ddwrt and AP openwrt the datarates were 866/433. TX won't do more than VHT-NSS 1 although RX it's not good either because it's a 4 chain 
>     > radio and it should do VHT-NSS4.
>     > 
>     > Thank you,
>     > Klevis
>     > 
>     > 
>     > 
>     > 
>     > On Mon, Sep 23, 2019 at 6:36 PM +0200, "Ben Greear" > wrote: > > Weeks or months or whenever I have time, and maybe
>     sooner if someone > wants to sponsor it. Please understand I, and
>     probably everyone else working > on OpenWRT, am busy with lots of
>     other projects and community work often > gets pushed to the back
>     burner. > > Thanks, > Ben > > On 9/23/19 8:18 AM,
>     support at maxnet.al wrote: > > Hi Ben, > > > > When do you think you
>     might be able to make those changes to your driver? > > > >
>     Thanks, > > Klevis. > > > > > > > > On 2019-09-20 13:00, Ben
>     Greear wrote: > >> On 9/20/19 12:55 PM, Vincent Wiemann wrote: >
>     >>> Hi Klevis, > >>> > >>> have you tried it with a short
>     distance? > >>> If you did you should better ask Ben Greear
>     directly. > >> > >> I asked him to post publicly so that others
>     can help answer and that > >> my own answers might > >> help
>     someone else. > >> > >> I have some patches that should enable
>     coverage class settings for > >> wave-2, but I am too busy > >>
>     with other things right now to port them to my ath10k-ct
>     driver/firmware. > >> > >> Thanks, > >> Ben > >> > >>> > >>> By
>     the way ath10k gen 2 chipsets don't work very well with long
>     distance links without a > >>> special feature which
>     implementation is only available to companies like Ubiquiti and
>     very few > >>> people who have an own reverse-engineered
>     implementation. > >>> It works on IPQ401X, QCA9886 and QCA9888
>     based chips only. > >>> > >>> And it is not possible to set a
>     coverage class for gen 2 devices, yet as far as I know due to
>     missing > >>> documentation and implementation (correct me if that
>     information is outdated). > >>> Furthermore a high channel width
>     often results in problems > >>> due to lower receiver sensibility.
>     > >>> We have better experiences with lower channel widths and
>     sometimes get more throughput with that. > >>> > >>> Actually I
>     think this does not explain your connection issues as 13 km is not
>     that much. > >>> > >>> Regards, > >>> > >>> Vincent Wiemann > >>>
>     > >>> On 20.09.19 18:30, support at maxnet.al wrote: > >>>> Hello
>     everyone, > >>>> > >>>> I am trying to setup a custom made outdoor
>     link with Apu2d2 board devices and QCA9994 cards from compex.
>     After i installed openwrt and ath10k ct driver, > >>>> kmod ath10k
>     and board-2.bin the device can run a 80MHz channel in WDS AP. The
>     problem is that it won't run as station or station wds. It can
>     scan > >>>> the SSIDs but won't connect them. > >>>> > >>>> Any
>     suggestion? > >>>> > >>>> Thank you! > >>>> Klevis > >>>> > >>> >
>     >>> _______________________________________________ > >>>
>     openwrt-devel mailing list > >>> openwrt-devel at lists.openwrt.org >
>     >>> https://lists.openwrt.org/mailman/listinfo/openwrt-devel > >>>
>     > > > > > -- > Ben GreearCandela Technologies Inc
>     http://www.candelatech.com > -- Ben Greear Candela Technologies
>     Inc http://www.candelatech.com
>
>
> _______________________________________________
> openwrt-devel mailing list
> openwrt-devel at lists.openwrt.org
> https://lists.openwrt.org/mailman/listinfo/openwrt-devel

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.infradead.org/pipermail/openwrt-devel/attachments/20190925/7303f995/attachment.htm>
-------------- next part --------------
_______________________________________________
openwrt-devel mailing list
openwrt-devel at lists.openwrt.org
https://lists.openwrt.org/mailman/listinfo/openwrt-devel