Slow WiFi and bad signal finally solved


#1

I think this will help a lot of Turris Omnia users to solve slow WiFi problem.

From the beginning I was quite satisfied with WiFi performance. My setup was personal 2,4 WiFi on first WiFi card (the dual one) and guest 2,4 on second card.

About a year ago I have lost signal on places where I had no problems before and WiFi got very slow over all. I have switch my personal WiFi to 5 ghz which partially solved speed problem but not problem with coverage. Guest WiFi went to hell…

I have spend a lot of time and some money to repair it but no succes. (Tried different antennas, WiFi cards … )

Few days ago I even considered to sell TO and while searching for replacement I hit warning on LEDE web about usb3 and WiFi problem.
And then I went like OMFG…

Flashback:

One year ago I was trying to install msata disk inside TO ,so I have to move 2,4 ghz card from the original slot to the “LTE” slot. And that was when the trouble started but at that time I didn’t know that this was the cause of the problem.

To make this long story short -

Usb3 ports in Turris Omnia interference with 2,4 WiFi !!!

If you have same problem move the 2,4 card to the slot close to cpu (or to the middle one if you use msata disk) and put the dual WiFi card to the last slot and run it in 5ghz mode. Also try to keep away antenna cables as far from usb3 port as possible.

This changes my 2,4 WiFi from 10 Mbit to 30 Mbits (test spot 8m behind 2 walls ) and sitting next to TO was 60 Mbits max now it’s 90 Mbits and also I have signal at the places I was used to.

And also my 5ghz went from 40 to 80 Mbits at the first spot - don’t know why because the usb3 should interference only with 2,4 ghz but it did.

Finally I like my Turris Omnia again :slight_smile:


#2

Well, if thats true, then this video isnt correct https://www.youtube.com/watch?v=71_M2N3ga7s


#3

Well this would explain all my strange issues with 2.4GHz wireless. Timemachine backuping data to USB disk instantly killing 2.4GHz makes total sense now.

Sadly I can’t really move my cards around, as I’m using mSATA slot. So is there some MacGyver hack that could help? Maybe adding some metal between/around circuits and/or cables to right places? Or maybe mPCIe extender cable might do the trick, allowing to relocate the 2.4GHz card further from USB3 traces and connectors?


#4

you can, I am using msata too.

The correct setting that works fine is:

  • Msata is in the slot that is closest to the cpu
  • 2,4 WiFi cars is in the middle
  • dual WiFi card is the last slot ( the one that is closest to usb 3 ports) and is set to 5ghz

And as I said : keeps cables away from usb3 ports


Length of wires running between wireless modules and antennas prohibit swapping them to other slots
Poor wifi performance
#5

Did anyone find a working mPCIe-extender? Ordered one via Amazon that unfortunately didn’t work… :expressionless:


#6

I just recalled that some tailored router firmware, tomato or merlin asuswrt, cater for coexistence with usb3 and bluetooth in their respective webgui, but I am not aware how that is achieved with the underlying code.


USB 3 Interoperability Issue

the noise from USB 3.0 data spectrum can be high (in the 2.4–2.5 GHz range). This noise can radiate from the USB 3.0 connector on a PC platform, the USB 3.0 connector on the peripheral device or the USB 3.0 cable. If the antenna of a wireless device operating in this band is placed close to any of the above USB 3.0 radiation channels, it can pick up the broadband noise. The broadband noise emitted from a USB 3.0 device can affect the SNR and limit the sensitivity of any wireless receiver whose antenna is physically located close to the USB 3.0 device. This may result in a drop in throughput on the wireless link.

Mitigation Methods
There are several areas where improvements can be made to minimize the impact of USB 3.0 noise on wireless device performance. Three areas where improvements can be made are:
• Shielding on the USB 3.0 peripheral device
• Shielding improvements on the USB 3.0 receptacle connector
• Wireless antenna placement, wireless receiver performance


Bluetooth Coexistence

An 802.11 device and Bluetooth can interfere with each other when the 802.11 device operates on the 2.4 GHz band. All Bluetooth devices operate at the 2.4 GHz band. If you experience wireless disconnects, decreased range or speed, and other connectivity issues when you turn on some of your Bluetooth devices, try to change this option to “Enable” (this will make the router and Bluetooth device to take turns in using the spectrum for communication) or “Preemption” (the router will inform the Bluetooth device about the channel it is operating on, and the Bluetooth device can preemptively disable communication on the respective Bluetooth channels).


#8

Hello,

My setup was personal 2,4 WiFi on first WiFi card (the dual one) and guest 2,4 on second card.

When you open your Turris Omnia you can find there two diplexers (signal splitters)


and by default we have connected pigtails, how they should be when you decided to use dual band card for 2.4 GHz frequency instead of 5 GHz in Foris you will see this warning:

I have to move 2,4 ghz card from the original slot to the “LTE” slot. And that was when the trouble started

This seems like you didn’t reset your Wi-Fi settings. There is a button in Foris to do it or you can remove /etc/config/wireless and restart your router and after the restart, it will generate a new wireless config for you and you’ll need to setup the WiFi again.

When you decide to connect m.SATA SSD then please follow the video, which was posted by @Jirka, where the small WiFi card is in the left slot.

Usb3 ports in Turris Omnia interference with 2,4 WiFi !!!

I think this shouldn’t happen with the small card. It’s very common that other routers use USB hub, but we don’t use any USB hub, because each USB is connected directly to the CPU. In a very theoretical way, it could interfere with a bigger card.

To make this long story short

Please use something like TL;DR, which is common on Reddit.

So you should have this:
the small card in the left slot
the bigger WiFi, which is dual band in the middle slot
and the mSATA SSD in the right slot.


#9

1/ From the biggining I have removed diplexers, I have 5 anntenas , no diplexers

2/ I did reset WiFi settings because since my trouble started I did many times hw reset and reflashed many times from medkit. I was really desperate …

3/ I am 100% sure that my Omnia usb3 ports interference with WiFi. its my real word experience and I am sure , that more users will confirm this when they try to change card a cables placement
Read alump’s post for example


#10

Did you test this with USB2 or USB3 connections? Assuming you tested with USB3: could you do a test using an USB2-cable/device


#11

Concept of USB3 causing issues with 2.4GHz is nothing new: https://www.intel.com/content/www/us/en/io/universal-serial-bus/usb3-frequency-interference-paper.html

For this reason it sound reasonable that maybe USB3 traces or connector on the board might be causing issues with 2.4GHz card when it’s located on specific slot. Also having USB3 device right next to 2.4GHz antennal the outside of metal case of Omnia could also cause issues.


#12

:frowning: Output from dmesg | less is stating something different

[ 7.735845] orion-ehci f1058000.usb: EHCI Host Controller
[ 7.741277] orion-ehci f1058000.usb: new USB bus registered, assigned bus number 1
[ 7.748924] orion-ehci f1058000.usb: irq 39, io mem 0xf1058000
[ 7.770960] orion-ehci f1058000.usb: USB 2.0 started, EHCI 1.00
[ 7.777152] hub 1-0:1.0: USB hub found
[ 7.780920] hub 1-0:1.0: 1 port detected
[ 7.786052] uhci_hcd: USB Universal Host Controller Interface driver
[ 7.795627] xhci-hcd f10f0000.usb3: xHCI Host Controller
[ 7.800981] xhci-hcd f10f0000.usb3: new USB bus registered, assigned bus number 2
[ 7.808575] xhci-hcd f10f0000.usb3: hcc params 0x0a000990 hci version 0x100 quirks 0x00010010
[ 7.817144] xhci-hcd f10f0000.usb3: irq 46, io mem 0xf10f0000
[ 7.823161] hub 2-0:1.0: USB hub found
[ 7.826931] hub 2-0:1.0: 1 port detected
[ 7.830968] xhci-hcd f10f0000.usb3: xHCI Host Controller
[ 7.836297] xhci-hcd f10f0000.usb3: new USB bus registered, assigned bus number 3
[ 7.843855] usb usb3: We don’t know the algorithms for LPM for this host, disabling LPM.
[ 7.852170] hub 3-0:1.0: USB hub found
[ 7.855938] hub 3-0:1.0: 1 port detected
[ 7.860009] xhci-hcd f10f8000.usb3: xHCI Host Controller
[ 7.865347] xhci-hcd f10f8000.usb3: new USB bus registered, assigned bus number 4
[ 7.872940] xhci-hcd f10f8000.usb3: hcc params 0x0a000990 hci version 0x100 quirks 0x00010010
[ 7.881506] xhci-hcd f10f8000.usb3: irq 47, io mem 0xf10f8000
[ 7.887502] hub 4-0:1.0: USB hub found
[ 7.891277] hub 4-0:1.0: 1 port detected
[ 7.895300] xhci-hcd f10f8000.usb3: xHCI Host Controller
[ 7.900627] xhci-hcd f10f8000.usb3: new USB bus registered, assigned bus number 5
[ 7.908161] usb usb5: We don’t know the algorithms for LPM for this host, disabling LPM.
[ 7.916480] hub 5-0:1.0: USB hub found
[ 7.920249] hub 5-0:1.0: 1 port detected


#13

Can you please post output of lspci with “correct” card order?
Thanks in advance.


#14

here you go:

00:01.0 PCI bridge: Marvell Technology Group Ltd. Device 6820 (rev 04)
00:02.0 PCI bridge: Marvell Technology Group Ltd. Device 6820 (rev 04)
00:03.0 PCI bridge: Marvell Technology Group Ltd. Device 6820 (rev 04)
02:00.0 Network controller: Qualcomm Atheros AR9287 Wireless Network Adapter (PCI-Express) (rev 01)
03:00.0 Network controller: Qualcomm Atheros QCA986x/988x 802.11ac Wireless Network Adapter


#15

Thank you @tomas.v !

I have exactly the same issue since I installed a mSATA SSD and had to move the 2.4 GHz to the very left (LTE) slot. It is good to hear that I am not the only one having the issue. I initially thought that the WiFi card or the PCI slot is causing the issue but your reasoning sounds plausible and provides an explanation.

@Pepe is there any reason why you don’t recommend swapping both WiFi cards? Why is it suggested to install the 5GHz card in the middle slot?

Thanks.


#16

I should say that we don’t use any external USB hub, but I thought you’d understand it.
Anyway, I recommend you to use command lsusb -t.

This is from Turris Omnia, where the output shows you that USB ports are really connected directly to the CPU as I said.

root@turris:/# lsusb -t
/:  Bus 05.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M
/:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M
/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M             
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M              
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=orion-ehci/1p, 480M 

If we’re using any external USB hub it will look like:

/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/6p, 5000M
    |__ Port 4: Dev 2, If 0, Class=Hub, Driver=hub/3p, 5000M
        |__ Port 1: Dev 4, If 0, Class=Mass Storage, Driver=usb-storage, 5000M
        |__ Port 2: Dev 3, If 0, Class=Vendor Specific Class, Driver=ax88179_178a, 5000M

and how it will look in dmesg | less

[    1.300394] hub 1-0:1.0: USB hub found
[    1.300408] hub 1-0:1.0: 12 ports detected

It’s not unusual to approach that multiple USB ports share the same bus and except as it is on motherboards for computers you’ll notice it nowadays in SBC like Odroid C2 and Raspberry Pi, where you’d notice that USB ports are also shared with Ethernet notice it as it uses the same controller, but it can cause issues with DVB tuners as it is described here as it shares bandwidth.


#17

Thank you @tomas.v
After seeing the ‘Slow WiFi and bad signal…’ thread I installed the mSATA closest to the CPU, the 2.4GHz card in the middle slot, and the 5GHz WiFi card in the slot that is between the CMOS battery and the USB3 port. This required me to rearrange the antenna wires to the WiFi card and I ran into a problem.
The middle hardwired antenna connects to the center (5GHz) port on the 5GHz card and it is not long enough to reach.
Additionally the cutouts on the Omnia case are keyed which prevents swapping the middle antennae into the diplexer slot that is just above the rear USB3 port.
Can you post information where to get the 5 antenna set you are using without diplexers, etc.
I inquired to turris support about purchasing a center antenna with a minimum 12 cm lead but no answer there.
Thanks.


#18

I use the original turris anthenas (3x) for 5ghz and bought aditional TP-link anthenas (2x) for 2,4Ghz. This setup needed aditional (longer) pigtails. Search shops for “Pigtail RG178, U.FL -> RSMA female” I have 20cm lenght but imho 15-20 cm is OK. if you are from Czech republic:
https://www.heureka.cz/?h[fraze]=Pigtail+RG178%2C+U.FL+->+RSMA+female%2C+20cm


#19

I was able to find the cable I needed by searching string you listed in your post. And in the process I learned a lot about both of these types of connectors.
Thank you!


#20

I’ve ordered a 15cm one. I will report back once installed.


#21

After having switched the cards, I can confirm that my 2.4 GHz connection is now stable and thus has fixed the issue. Thank you @tomas.v for the suggestion!

Btw. 15 cm is more than sufficient, ideally would be something around 12 cm.