3x3 MIMO link speed problem.

Hi, I have wireless link build on Intel DN2800MT,1GB ram and compex wle300nx 6a as wireless card, but I am unable to get higher wireless speeds then 300/300 Mb/s

Does that card support more then 300 Mb/s?

ROS 6.0beta3 on x86

/interface wireless
set 0 adaptive-noise-immunity=none allow-sharedkey=no antenna-gain=0 area=“”
arp=enabled band=5ghz-a/n basic-rates-a/g=6Mbps basic-rates-b=“”
bridge-mode=enabled channel-width=20/40mhz-ht-below compression=no
country=“czech republic” default-ap-tx-limit=0 default-authentication=yes
default-client-tx-limit=0 default-forwarding=yes dfs-mode=none
disable-running-check=no disabled=no disconnect-timeout=3s distance=
dynamic frame-lifetime=0 frequency=5700 frequency-mode=manual-txpower
frequency-offset=0 hide-ssid=no ht-ampdu-priorities=0 ht-amsdu-limit=8192
ht-amsdu-threshold=8192 ht-basic-mcs=
mcs-16,mcs-17,mcs-18,mcs-19,mcs-20,mcs-21,mcs-22,mcs-23
ht-guard-interval=any ht-rxchains=0,1,2 ht-supported-mcs=
mcs-16,mcs-17,mcs-18,mcs-19,mcs-20,mcs-21,mcs-22,mcs-23 ht-txchains=0,1,2
hw-fragmentation-threshold=disabled hw-protection-mode=none
hw-protection-threshold=0 hw-retries=7 l2mtu=2290 mac-address=
00:80:48:77:04:4E max-station-count=2007 mode=ap-bridge mtu=1500
multicast-helper=default name=wlan1 noise-floor-threshold=default
nv2-cell-radius=30 nv2-noise-floor-offset=default nv2-preshared-key=“”
nv2-qos=default nv2-queue-count=2 nv2-security=disabled
on-fail-retry-time=100ms periodic-calibration=default
periodic-calibration-interval=60 preamble-mode=both
proprietary-extensions=post-2.9.25 radio-name=00804877044E
rate-selection=advanced rate-set=default scan-list=default
security-profile=default ssid=SPKFree-FINtoMTS station-bridge-clone-mac=
00:00:00:00:00:00 supported-rates-a/g=6Mbps supported-rates-b=“”
tdma-period-size=2 tx-power=3 tx-power-mode=all-rates-fixed
update-stats-interval=disabled wds-cost-range=50-150 wds-default-bridge=
none wds-default-cost=100 wds-ignore-ssid=no wds-mode=disabled
wireless-protocol=unspecified wmm-support=disabled

tx-power at all rates fixed = 3
range ~500m

Hi
Try to setup: only-N mode and set MCS to 20,21,22,23

disconnected

This means that you have a problem with the antenna. What antennas are there?

80cm offset dish at both sides - 3x3 mimo @ 120° deggres irradiator

what kind of antennas / dishes?

tks

Hello,
I have the same problem. I have link 500 metres out of 3x3 antennas and cards
WLE350N5-23 7B.
The signals are acceptable in all chains.
Current-tx-powers shows maximum msc-7, it responds to link rate 300/300Mbps.
Please, have you any idea, what is the problem?

Used cards: WLE350N5-23 7B (AR9590) http://www.compex.com.sg/productdetailinfo.asp?model=WLE350N5-23&acc1Panel=1
Used antennas: https://ispforum.cz/download/file.php?id=2239



[admin@r-hsauto.sporknet.cz] > /interface wireless monitor wlan1
status: connected-to-ess
band: 5ghz-n
frequency: 5640MHz
wireless-protocol: nv2
tx-rate: 300.0Mbps
rx-rate: 300.0Mbps
ssid: SPR-SI-HSA
bssid: 04:F0:21:02:70:C7
radio-name: 04F0210270C7
signal-strength: -55dBm
signal-strength-ch0: -61dBm
signal-strength-ch1: -59dBm
signal-strength-ch2: -59dBm
tx-signal-strength: -54dBm
tx-signal-strength-ch0: -60dBm
tx-signal-strength-ch1: -60dBm
tx-signal-strength-ch2: -59dBm
noise-floor: -111dBm
signal-to-noise: 56dB
tx-ccq: 99%
rx-ccq: 82%
overall-tx-ccq: 56%
authenticated-clients: 1
current-distance: 1
wds-link: no
bridge: no
routeros-version: 5.25
current-tx-powers:
6Mbps:3(3/8),9Mbps:3(3/8),12Mbps:3(3/8),18Mbps:3(3/8),24Mbps:3(3/8),36Mbps:3(3/8),48Mbps:3(3/8),54Mbps:3(3/8),HT20-0:3(3/8),HT20-1:3(3/8),

HT20-2:3(3/8),HT20-3:3(3/8),HT20-4:3(3/8),HT20-5:3(3/8),HT20-6:3(3/8),HT20-7:3(3/8),HT40-0:3(3/8),HT40-1:3(3/8),HT40-2:3(3/8),HT40-3:3(3/8),

HT40-4:3(3/8),HT40-5:3(3/8),HT40-6:3(3/8),HT40-7:3(3/8)
notify-external-fdb: no

If you look at the CCQ%'s than the two best are given and a poor overall. So you should take a closer look at the CCQ’s of each individual chain. Maybe one of the chains is performing poor.
Than, if you identified a poor chain, look at its cable connections/connectors, its polorization, the environment (could it be just that polorization is beeing reflected by a metal roof?) etc.
Also try some other frequencies to see if there is no inteference.
For instance, if there is interference it will probably effect most only one chain. The one with the same polorization as the interfering signal…

ROS general status figures only produce the best found on the 3 chains. Hence good ‘top’ ccq, good signal, low noise etc. But it might well be one of the chains is doing very poor.

Why is the ‘general’ info basically telling the link is ok? Well, you can make a 300Mb conn. rate. Which can be considered ‘good’. But we know a 3 chain link can do better. ROS don’t. So dig a bit deeper and probably find the culprit.

And let us know off course! I´m also only talking out of ‘common sense’ and a bit of experience… :astonished:

@spork
Could we have more details on the antenna’s used?

Used antennas: > https://ispforum.cz/download/file.php?id=2239

It is standard antenna with emitters moved 120*- Vertikal 0*,120*,240*.
The question is, how should be polarization plugged in the rard.
I have it now that chain 0 is 0*, chain 1 is 120* and chain 2 is 240*

The problem with 3 chains is that 3 polarizations have very low separation compared to 2 polarizations.
If I remember right it is only like 3to6 db compared to 12db. So in a clear LOS this might be not enough.

I see none of the 11n based gear vendors offering a 3 chain solution. So it most likely do not work very
well at all.

a. Try to put “adaptive-noise-immunity” to both AP and client enable.
b. I think feeder is not right as you have it. :frowning:

http://www.lanbowan.com/_d4.htm?c=1123
But I do agree with “ste”. The cross chain separation might not be very good.

But to be honest I think the availability of 3 (or 4) chain antenna’s is merely a “chicken or the egg” issue. Most vendors wont make them untill there is demand for them. But demand won’t grow a lot if there are hardly antennas on the market.
Some main stream antenna makers only recently are bringing 2 chain antenna’s out…

One other solution I personally am thinking of is to use a good shielded (metal dish) dua chain antenna (H+V- pol) and to fit separately a single chain directional (also good shielded).
By fitting them with some small separation you create a high cross chain difference where from distant seen this setup still funcions as one triple chain antenna. This third antenna can than be setup with a 45 or 135 angle. (Make sure on the other end the angle is the same, not opposite! :astonished: )

My only quiery I have in such setup is the length of the cables/pigtails between actual radio and the antenna(s). Should they be exactly the same, or would a difference in length (= time) make some difference to the good or bad?