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theoberlin
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Low Bandwith with SXT ac

Thu Apr 07, 2016 10:13 am

Hi Guys,

i'am from berlin and i have a problem with 2 SXT ac Wireless stations.

The Wireless bridge is connected with a distance round about 1500 meters. I have a Signal Strength of -48/-48 and a TX/RX Rate of 585-866 Mbps (normally 80Mhz/2S)

The real bandwith going through the Bridge is just nearly 105 Mbit. This is not depending on the wireless protocoll or channels used. This is the absolute maximum transmission speed if i have the connection speed above (checked with bandwith test Tool). The UDP transmission speed is up to 360 Mbit but with a big paket lost. The connection is Gigabit but thats no point because the internal bandwith test create the same results.

Any ideas to create a higher bandwith over the air?

Best

Theo
 
zyzelis
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Re: Low Bandwith with SXT ac

Thu Apr 07, 2016 1:06 pm

Hi Guys,

i'am from berlin and i have a problem with 2 SXT ac Wireless stations.

The Wireless bridge is connected with a distance round about 1500 meters. I have a Signal Strength of -48/-48 and a TX/RX Rate of 585-866 Mbps (normally 80Mhz/2S)

The real bandwith going through the Bridge is just nearly 105 Mbit. This is not depending on the wireless protocoll or channels used. This is the absolute maximum transmission speed if i have the connection speed above (checked with bandwith test Tool). The UDP transmission speed is up to 360 Mbit but with a big paket lost. The connection is Gigabit but thats no point because the internal bandwith test create the same results.

Any ideas to create a higher bandwith over the air?

Best

Theo
What frequency? CCQ?
Probably noisy area? run frequency usage/scan tools and post here
 
theoberlin
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Re: Low Bandwith with SXT ac

Thu Apr 07, 2016 2:38 pm

Hi zyzelis,

CCQ is between 70 and 86 %

frequency is 5660/20-eeeC/ac

Frequency usage is 0 between 5600 MHz and 5660 MHz and 28,6 on 5680 Noise Flor is -107

What frequency? CCQ?
Probably noisy area? run frequency usage/scan tools and post here
 
noib
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Re: Low Bandwith with SXT ac

Thu Apr 07, 2016 2:47 pm

Did you try with 40Mhz width instead of 80 ?
Did you try to change frequency ?
When doing your tests, did you check if SXT's CPU was not reaching 100%?
Did you run a /wireless spectral-scan wlan1 (not sure if SXT-ac radio supports this command).
 
theoberlin
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Re: Low Bandwith with SXT ac

Thu Apr 07, 2016 3:04 pm

Hi i Tryed 40 Mhz and now i have a Bandwith between 113 and 130. A little bit better.

I used different frequencys without any changes

BUT

The CPU reached nearly 100%!! (round about 95%)

On a real Download the CPU reached round about 30% but the Bandwith is again between 60 - 120 Mbps

Best

Theo
Did you try with 40Mhz width instead of 80 ?
Did you try to change frequency ?
When doing your tests, did you check if SXT's CPU was not reaching 100%?
Did you run a /wireless spectral-scan wlan1 (not sure if SXT-ac radio supports this command).
 
kiaunel
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Location: Germany

Thu Apr 07, 2016 3:27 pm

Fitst of all -48 is a little to high signal. Try to set antena gain if you have it 0 to 2-4-6-8-10 on both devices until you get around -55 -60 signal. On these signals I get most stable links. Second if your scan tool does not see interference does not mean there isn't. Try to change channels until you get most stable one. Third, never do test to devices that are connected to the link, use some computer to computer test like iperf or something... You will get better results.

Sent from my Lenovo K50a40 using Tapatalk
 
theoberlin
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Joined: Thu Apr 07, 2016 10:03 am

Re:

Thu Apr 07, 2016 3:30 pm

After changing the protocoll to nstreme and 80Mhz Channel i have a CCQ of 99% and a real Troughput of 200Mbps.
The CPU is round about 47%

I tried other values but it dosnt work. TheSignal Strength value don't change. I tried values up to 30. The Signal value is till -47 to-49

Another question, whats the "real world" value to reach with this model?

Best
Theo
 
theoberlin
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Re: Re:

Thu Apr 07, 2016 3:54 pm

The Gain Value were chacked as "manual Tx Power" to setting this to regulatory-domain the changes will work.
With a signal Value of -56 i have a througput maximum on 210 Mbps is there any way to increase the value?
After changing the protocoll to nstreme and 80Mhz Channel i have a CCQ of 99% and a real Troughput of 200Mbps.
The CPU is round about 47%

I tried other values but it dosnt work. TheSignal Strength value don't change. I tried values up to 30. The Signal value is till -47 to-49

Another question, whats the "real world" value to reach with this model?

Best
Theo
 
theoberlin
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Re: Re:

Fri Apr 08, 2016 11:55 am

Hi Guys,

i think i found the settings for the maximum throughput:

Protocoll NStream (NV2 is just 50% of it)
20 dbi Antenna value
80 Mhz Channel

This results in 650 Mbps and a CCQ of 98%.

now I have a througput between 18 and 29 MB/sec normally round about 22 MB/sec

With 5dbi antenna gain i have a connection bandwith between 720 and 866 Mbps but the real throughput is slightly lower.
If i choose 40 Mhz Channel bandwith the troughput is just round about 16 MB/Sec but very stable.

If anyone nows how to increase this value again please gove me this information.

I attached some details of the bandwith.

Thanks for you help.

Al the Best

Theo
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