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WiFi Scan results

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AC2OG
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WiFi Scan results
Hello,
a wifi scan on one of my nodes produced the following result:

a WiFi scan on one of my nodes produced the abone result. In what band/range are located the channels: 3455 and 3475 ?
 
AC2OG
AC2OG's picture
WiFi scan results
 Hi here the scren-shot missed in my previous message
File Attachment: 
nc8q
nc8q's picture
Channel 3475

Hi, Ari:

I have seen this many times, also.
May be related to upconverting a 2400 MHz signal to 5800 MHz.
3475+2400=5875 MHz

Chuck
 

Image Attachments: 
AC2OG
AC2OG's picture
Channel 3475
Hi Chuck,
thanks for your quick feedback! I am worried of the noise and interference caused by this to my network operating at 5,835 GHz, near to 5,875 GHz and 5,855  GHz.  Is it an inter-modulation product created by the radio of my node or really an up conversion to translate a 2,4 GHz signal ? 
But why is the SSID hidden ? Is it legal ?
Have a nice week end.
Leo, I3RKE/AC2OG
nc8q
nc8q's picture
Channel 3475

"I am worried of the noise and interference caused by this "

Hi, Leo:

 The amount of signal degradation by this anomaly may be none, insignificant, and/or unmeasurable.
Veni, vidi, vici
I am not worried. ;-)

Chuck

AE6XE
AE6XE's picture
This signal showing as 3485
This signal showing as 3485 is really a signal on 5485 out of WiFi part 15 compliance.    This is based on the SSID showing.   The 3GHz devices are really 5GHz devices with a -2GHz down converter.   When a 3GHz freq is shown on a 5 GHz device it can happen for these 2 reasons:

1) it is a device just below ch 100, which is outside WiFi part 15 compliance.
2) it is really a 3GHz AREDN device in close proximity and there is bleed through from the motherboard.

since we don't expect there to be 802.11n signals in this 5GHz space, the UI was written to display it as option 2.  If we think that option 1 is more prevalent, can always change the UI to option 1.  Regardless, both options exist, and the UI will get it wrong some of the time.

Joe AE6XE
AC2OG
AC2OG's picture
Channel 3475
Hi Chuck,
thanks for your reassuring reply, but it's a fact that in that node I have a poor LQ, ranging from 30 to 60 %.
I hope you are right.
73 de Leo, I3RKE/AC2OG.
nc8q
nc8q's picture
poor LQ
Hi, Leo:

I would need much more information than has been presented so far.
I assume, from your earlier .docx, that you are operating on 5.765 GHz -  channel 153.
You mention a possible signal at 3.475 GHz.
Your .docx indicates a SNR of ~26 dB ( ( -69 ) - ( -95 ) ).
If that SNR is at each end (and no other same channel stations), there should be LQ/NLQ 100%.

Maybe show WiFi scans from each end of the desired link. :-|

Have you tried other channels?

Chuck
 
AC2OG
AC2OG's picture
Poor LQ
Hi Chuck,
we have a problem in the following link of the Mesh : IQ3QR-1 to IQ3QR-3.
IQ3Q3-3  is the link where I noted the problem I told you with my first post.
Please have a look at the attached docx related to the complete mesh.
Leo.
File Attachment: 
nc8q
nc8q's picture
Oh, 3 stations on the same channel. :-(
Hi, Leo:

More than 2 stations on the same channel will cause interference.

"IQ3QR-3 is loosing 32% of the packets."
LQ 62% means losing 32% of (sequential) broadcast packets not data packets.
Loss of data packets is likely worse.

"Here the complete mesh that is working fine in all the segments, but not at IQ3QR-3 to IQ3QR-1 in which the ETX should be 3.20 and not 4.21."
Actually,  I think that 4.21 is from I3RKE-1 to IQ3QR-1.

Hopefully IQ3QR-3 and IQ3QR-4 can hear each other.

Chuck

 
AC2OG
AC2OG's picture
WiFi scan results
HI Chuck,
Yes, 4.21 is from I3RKE-1 to IQ3QR-3. 
for a better evaluation, I attach a new docx showing my mesh, that I resume here below:
On the top of a hill two nodes: IR3UFR-1 (5.835 GHz) and IR3UFR-2 (5.765 GHz) linked D.t.D with an 802.1Q switch. Each one with a 60° sector antenna.
The nodes I3RKE-1, IW3HRW-1, IK3HTH-1, IZ3JSF-1, IW3GOZ are linked to IR3UFR-1
The nodes IQ3VV-2, IZ3YJO-1, IW3HNP-1, IQ3QR-5, IQ3VV-4 are linked to IR3UFR-2

On the top of another hill (hidden from the first) I have the node: IQ3QR-1 (5.835 GHz)  with a 120° sector antenna.
The nodes IQ4QR-3, IQ3QR-4 are linked to IQ3QR-1 (they can't hear each other).
IQ3QR-5 is linked to IQ3QR-3  D.t.D.  with an 802.1q switch.

Last point that I would like to stress is that sometimes the whole mesh is working perfectly, then suddenly became worse. 

Leo

 
File Attachment: 
nc8q
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then suddenly became worse.

Hi, Leo:

Opinion 1.: With 6 stations all on the same frequency and even at megabit speeds,
there will be times that are good and times that are bad.
Bad times especially if 2 or more of the stations are transferring data.
Good times when no data is being passed and folks are just watching their /mesh pages auto-update. :-|

Opinion 2.: You do not need an 802.1Q switch to DtD link devices. A simple layer-2 switch will work.
If only 2 nodes, simply connect the LAN ports of the POEs with a straight or crossover cable.
( Maybe all POE's LAN ports are auto-switching (MDI, MDI-X). )
If you choose to leave nodes in default AREDN state and
need to attach a device (camera, IP-phone,workstation,...) to the LAN port of a specific node,
then you need a VLAN (802.1Q) switch.

Minor Opinion 3.: Use unique Hostnames. As your network grows and especially if you might
join another network, ensure that Hostnames are unique. A common standard for ensuring that
Hostnames are unique is to add the operator's callsign.
I3RKE-Raspi-CAM is unique.
'Lenovo-PC' and 'RASPI-PBX' might not be unique in a larger network.

Minor opinion 4. Is the '-1', '-2', '-3' parts of the Node Name required by law or
can you skip the '/tactical' and just use descriptive node names?  Examples:
AB8XA-Mobile
AB8XA-Mobile-hAP
AB8XA-NSM2-WNW
AB8XA-NSM5
AB8XA-NSM9
AB8XA-Portable
AB8XA-Portable-hAP
AE8I-3-TippCity
AE8I-5-TippCity
kd8dgh-CMHhosp
KD8PNV
KD8PNV-5
KD8UQI-200
KE8MVM-DARA-TO-XWARN
KE8MVM-MVHS-AGM5
KE8MVM-MVHS-Omni
KE8MVM-W-Xenia-NSM5
KF8MZ-LAPTOP
KF8MZ-MTIK5G
KF8MZ-NANO1
KF8MZ-RPI2-2-GL150USB
N2MH-AR-MVMA
N2MH-Hub
N8JJ-M5-BVRCRK
N8JJ-NSM9-1
N8JJ-Services
NC8Q-3-to-KC8JJH ; '-3' because this is a 3 GHz device
NC8Q-5-to-KC8JJH ; '-5' because this is a 5 GHz device
NC8Q-9-to-KC8JJH ; '-9' because this is a 900 MHz device
NC8Q-AR750
NC8Q-DARA-MVHS
NC8Q-DARA-VWT
NC8Q-hAP
NC8Q-M2-34
NC8Q-M3-Kett
NC8Q-M5-Kett
NC8Q-M5-MVHS
NC8Q-MVHS-BT
NC8Q-MVHS-PP
NC8Q-newLHG-81
NC8Q-PBE-M5-400
NC8Q-PP-MVHS
NC8Q-PP-Yankee
NC8Q-SXT-12
NC8Q-uAP2
NK8B-uAP1
w4qed-nl20-u100
W6CDR-hAP
W6CDR-MadRiv-Helke
W6CDR-MadRiv-MVHS
W6CDR-MVHS-MadRiv
W8BI-DARA-Omni
W8BI-DARA-Services
W8FW-USB150
W8GUC
W8GUC-2
W8GUC-3
W8LRJ-hAP
WA8APB-NSM2-Rotor
WA8APB-NSM3-Rotor
WA8APB-NSM5-Link2
WA8APB-NSM5-Rotor
WA8APB-NSM9-Rotor
WA8APB-Services
WX8WIL-NWS-Wilmington

 

I hope this helps,
Chuck
 

AC2OG
AC2OG's picture
then suddenly became worse.
Hi Chuck,
I put the 802.1q switch because I need hosting there a PC and services to be deployed later.
Unfortunately, I can count on 2 frequencies only,  5,765 GHz, and 5.835 GHz !!
I'll try to improve the link between IQ3QR-3 and IQ3QR-1 with different antennas or search to discover where is coming from the strange 3.455 GHz and 3.475 GHz A.P.  signal with hidden S.S.I.D.  Hi Hi.
I'll keep you posted.
I'll appreciate also some suggestions from Joe.
73, Leo.
AC2OG
AC2OG's picture
WiFi scan results
Hi Chuck and Joe,
thanks a lot for your support. To complete the info I attach the results of a WiFi scan from both endpoints, with some notes.
Concerning what Joe pointed out, here in Italy the 3 GHz band is not allowed either to I.S.P.  and to Amateur Radio Operators.
So I must conclude that it's a 5.475 - 5.455 GHz signal. As such it should not create problems.
Leo
nc8q
nc8q's picture
affected by the problem of the AP at 3.455 GHz and at 3.475 GHz.
Reference: endpoints.docx
I see no evidence that your network is 'affected' by the '34xx' signals discovered in the WiFi scan.
Channel 153 signals do not 'affect' channel 167 signals.
I see no evidence that '3455' nor other '34xx' signals 'affect' channel 153 and 167 signals.
-----

I have a link wherein one end displays 88 stations in the WiFi scan, yet there is seemingly no affect:

Current Neighbors          LQ    NLQ    TxMbps          Services
NC8Q-MVHS-PP        100%    100%    57.8        NB1728
 
Chuck
 

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