BPI R4 WiFi range

[SpectreDev]

Is it only me or is there an actual issue with the range of the BPI-R4, I can’t seem to get a signal upstairs in my house and my house is not massive at all, my isp provided router 5GHz could reach all over the house however the BPI-R4 cannot, I can connect to 5GHz but I can’t get WiFi at all the phone says no internet connection,

Does anyone else have the same issue and know a solution?

I am running Openwrt from the openwrt firmware selector.

[Thanks]

Maybe lowering the maximum transmit power will solve your problem.

Changing WiFi Power! Good or Bad?

[danpawlik (Dan)]

What module are you using? If bpi-r4-nic-be14 then I can say that signal on the same floor is really awesome, but can’t compare how it is on other floor. I can ask my neighbor if nobody will reply you. Try to change the antena possition

[SpectreDev]

Yeah it’s the BE14 my 2nd floor is the real issue, 4 antennas are flat and 2 are up, yet 5ghz struggles, it connects but either its not fast enough or the phone struggles to get a connection

[SpectreDev]

its helped somewhat, i get 60-100mbps now on 20dB, compared to before at 1mbps or lower and most of the time no connection at all

Edit: didn’t actually help much in 1 area, I only get 1.6mbps

[danpawlik (Dan)]

So I’m using channel 100 or 124, 160width, AX, country PL. I’m able to set 26dBm, but normally 20dBm is enough for one part of my apartment. Second no matter how good ap would be, it will not handle 7 walls (summary,partition walls and ventilation chimney). I’m sure that my neighbor up and down got signal.

Just curious, what power supply you have? If something is wrong, probably you will see some error or random reboots, but maybe… The antennas what you have was from the be14 kit ?

[SpectreDev]

i originally had antennas from the be14 kit but they were horrible so i sent it back and brought different antenna kit from digikey (GW.52.A153), which Vader said was a really good antenna, i saw some improvement with it and used a rg178 20cm cable all the way round. and as for the power supply its a anker usb c 65w GaN charger. i dont get any random reboots and the charger right now is probably overkill since i dont even have an SFP stick yet

[Thanks]

Try these WiFi settings on the 5 GHz band:

• Mode: AX or AC (do not use BE mode because the driver is not yet mature)
• Channel: 36 or 149
• Width: 40 MHz or 80 MHz (never use 160 MHz width in the 5 GHz band)
• Country Code: Guatemala [GT] or Japan [JP] or Panama [PA] or United States of America [US]

  Note: Change the country code because it is mandatory for proper WiFi functioning and all radios need to be on the same country, for the 6 GHz band to work, choose a country that support the 6 GHz spectrum.

Watch this video:

BEST WiFi Optimization Settings!

If doing that doesn’t improve the speed then maybe the problem is in the mt76 driver or in your cell phone, in another post you mentioned that your cell phone is a Sony Xperia, this cell phone is niche and is not recommended.

Also try another cell phone model such as Google Pixel, iPhone or Samsung to see if the same problem occurs.

[SpectreDev]

Will try this , thanks for trying to help

[Thanks]

You can also start from scratch to configure the WiFi:

• Regenerate wireless configuration

  To rebuild the configuration file, e.g. after installing a new wireless driver, remove the existing wireless configuration (if any) and use the wifi config command:

  rm -f /etc/config/wireless
  wifi config
  

[SpectreDev]

Ok a quick update on the situation, I use SFP copper wan now (only temporary till I move to full fibre) I’m starting to 5ghz albeit not at the same speed my isp router can do it it at which is 270mbps,.I’m getting somewhere between 33mbps to 80mbps which is a massive improvement over the previous speeds and not being able to connect at all, not sure what’s happened here, also can someone suggest a heatsink for the SFP since they get blistering hot

[Thanks]

@SpectreDev

can someone suggest a heatsink for the SFP since they get blistering hot.

Maybe these copper heatsinks will help you, I think the dimensions of the heatsink should be 40x40x10mm for BPI-R4 and 35x35x11mm for BPI-R3, these heatsinks do not come with thermal pad or thermal tape, you need to buy it.

AliExpress Links:

Cooltex:

• 40x40x10mm | 35x35x11mm
• 35x35x11mm

Cotexer:

• 40x40x10mm
• 35x35x11mm

.

40x40x10mm (BPI-R4)

35x35x11mm (BPI-R3)

Source:

• OpenWrt Support for Banana Pi BPI-R3 - #161 by tduffy83 - OpenWrt Forum
• My BPI R4 went DEAD - #1 by ljy26

.

P.S. Maybe these small heatsinks can also help you:

• [BPI-R4] and SFP - #282 by Thanks

[Betonmischer]

I’ve posted this on the OpenWrt forum, but this might be a better place. I noticed the SNR of 5 GHz clients one room away as seen on the router to be rather poor, which might be the root cause of coverage issues.

My old Archer C7 router shows the same signal strength for the clients, but noise level in the -100 dB range. Noise level on the BPI-R4 is -81 dB at best with Taoglas antennas and RG178 cables. I’d like to hear an expert opinion whether it’s normal to have such a high noise level and if this is something that can be improved by future drivers rather than a hardware flaw.

[kusmi (Michael Kussmaul)]

I see the very same thing with stock antenna (the ones bundled on AliExpress with BananaPi): On the BananaPi I have a reported noise level of around -80 dBm on both bands (5G, 6G), while on my client (MacBook) it is in the -95 dBm range. So it looks like the noise level is quite high on the BananaPi.

[SpectreDev]

Furthest room in my house and it’s the upper floor

[Thanks]

You can try with the official Banana Pi firmware that uses “proprietary” drivers to see if the same problem occurs:

• Banana Pi BPI-R4 | System Image

If the problem is solved when using Banana Pi firmware, it means that the culprit is MediaTek “open source” drivers, but if the problem occurs on both firmware (Banana Pi firmware with “proprietary” drivers and OpenWrt firmware with “open source” drivers), then the problem is in the Wifi 7 module design (BE14).

Remember that the BPI-R4 uses diplexer on the 2.4 GHz and 5 GHz bands (or radios), so both bands (or radios) use the same antennas, you can also try turning off the 2.4 GHz radio and only use the 5 GHz radio to see if this improves the SNR (Signal-to-Noise Ratio), this is the first time that Banana Pi uses diplexer and maybe it is poorly executed.

• Banana Pi BPI-R4-NIC-BE14 | BananaPi Docs
• Banana Pi BPI-R4 Wifi 7 Module design
• [BPI-R4] Which Wifi-Module version do you prefer?
  

.

What is the Signal-to-Noise Ratio and Why You Need to Measure it

01. Understanding Signal-to-Noise Ratios

SNR isn’t a ratio, as in “there is 75% signal to 25% noise”, but is measured by taking the signal strength and subtracting the noise, not dividing it. Adding to the potential confusion is that the signal is measured in decibels. For those who work in audio, most people consider decibels a measure of sound as in how loud something is.

It gets worse. In WiFi, decibels are measured in negatives. If you remember old grade school math, negative numbers are the ones below 0. So if you have -15 dBm (deciBels per milliwatt), that is a stronger signal than -50 dBm. I know - it’s confusing, but once you get that the higher the number, the weaker the signal, the better off we’ll be.

Let’s take a look at two different rooms. In one, the average signal strength is -20, the noise is around -60. To get the signal to noise ratio, it’s the signal minus the noise, which means we have an average signal to noise of 40 in this case:

How about room 2, where the signal is also -20, but the noise is -25. Now our signal to noise is much lower — around 5:

Notice how difficult it is to tell the difference between the signal and noise lines on this chart compared to the first one? That’s the rule: the lower the signal to noise ratio, the worse communication will be. We want a nice, big number for our SNR or S/N ratio since that means there’s a lot of distance between our signal and our noise.

02. What is a Good Signal to Noise Ratio?

Remember that Signal to Noise ratio, sometimes referred to as S/N ratio, isn’t a “ratio” but the difference between the signal-to-noise. So the bigger the number, the better.

Most experts recommend that an SNR of 20 dB just for data — this is surfing the web, looking up charts and other related traffic. If you’re looking to stream high-quality videos or make good voice/video chats, then an SNR of 25 is going to be required. Here’s a list of what kind of Signal-to-Noise ratios to follow:

• 5dB to 10 dB: Just give it up now. Stop what you’re doing, and fix the problems. The noise is so high that its indistinguishable from the signal.

• 10 dB to 15 dB: Really slow, but at least there’s a signal. If all you’re doing is getting basic emails, then you can get by. Barely.

• 15 dB to 25 dB: This is average and competent for web browsing and file downloading. Just don’t expect to be watching 1080p videos off Netflix and Youtube at a good rate.

• 25 dB to 40 dB: Fast speed. This is where you can do video conferences, stream high-speed videos, and download large files like gigabyte sized .iso files or movies.

• 40 dB and Up: You are in the Matrix, and have become the One.

Of course, this will be determined by your basic bandwidth strength. If your bandwidth strength is only -5 dB and your noise is 0, then your Signal to Noise is great but your signal strength is still trash. So first make sure the signal is strong, then focus on the signal to noise ratio.

03. How to Measure Signal vs Noise

One of the most useful tools that work as a signal to noise calculator comes from NetSpot.

The process is so easy, it’s just a few steps:

1. Launch Netspot.

2. Select Inspector.

3. Select the WiFi network in question.

4. Find the Signal and Noise levels.

5. Subtract Signal minus Noise to get to the SNR.

Take our sample network. Here we have a signal of -39, and a noise of -80. So running this through our signal to noise calculator and we get (-39) - (-80) = 41. Or to save time, just look at the Level setting. If it’s green, the signal is clean.

04. Fixing SNR Issues

Fixing Signal to Noise issues can take a multitude of approaches. First, get a WiFi signal analyzer. We’ve already mentioned NetSpot, and that’s a great place to start. It shows a list of all of the networks it identifies.

Once you see the list of WiFi signals, you can do a few things to increase the SNR ratio:

1. Remove Extra WiFi networks. This is especially true if this is a business environment. There are few reasons for someone to be running a separate WiFi network, whether it be from their cell phone and tethering or otherwise. With NetSpot, you can get an idea where it’s at as you trace it’s signal strength.

2. Check for “Noisy” devices. Take a look at the devices around the WiFi router. Is it next to a television, refrigerator, or other electronic devices? Try moving it away a bit. There was once a place with awful WiFi coverage until someone discovered that the WiFi router was next to the company’s fire alarm bell. Once it was moved away, the signal noise dropped.

3. Turn off unneeded signals. Some routers support multiple bands in the 2.4 GHz and 5 GHz range. Try turning off the 2.4 GHz signal if it’s not needed — it’s overcrowded compared to its 5 GHz sibling.

[Betonmischer]

Thanks for sharing your noise figures. I wonder if they could be improved by putting an RF shield on the BE board. It already has a line of solder pads around the ICs for that purpose. Plus, it would be nice if someone with the knowledge of RF circuit design took a look at the schematics to check if the noise is related to things like insufficient output filtering on voltage converters, etc.

[Thanks]

Here @simon mentions that the new WiFi 7 module models will use ePA (external power amplifier):

@simon

I will seriously consider whether to make a 10-antenna version, and maybe with ePA

@simon

ePA=External PA.

Many MTK chips have buildin PA/LNA inside, that’s iPA, but the power is not very high,

we can get higher power with an external PA.

[Betonmischer]

Thanks for sharing those tips. The stock firmware doesn’t report SNR and noise for clients, but I observed the same disproportional drop in transfer speed from the client to the router at distance. Turning off the 2.5 GHz radio didn’t help either. Even the proprietary driver likely isn’t perfect at this point to rule out a software issue, but I’m starting to suspect a hardware one.

It’d be nice if someone from the dev team took notice and shared the CAD for the RF shield so we could order one that would be a perfect fit. I’m sure they had it designed even though the shield didn’t make it to production. I’d like to try a makeshift shield made out of a piece of thin metal, but my BPI-R4 is buried inside its stock housing and already set up as a primary home router, which makes experimentation difficult.

[Betonmischer]

@simon Would you spare a minute to chime in to point out the likely source of high noise on the BE14 and whether there’s something we could do to reduce it?