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ansky
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hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 2:53 am

I have a laptop with a RTL8821CE wifi chip and I'm getting a maximum of 20 Mbps no matter what.
Another laptop with an older intel chip gets 300 Mbps. My samsung smartphone gets 300 Mbps.
Wired I get the full 1 Gbps.
Yesterday I connected my laptop (the RTL8821CE one) to a public hotspot and was getting 150 Mbps.
I tried playing with TX powers on both the router and the laptop : no change.
I tried playing with the channel widths : no change.
I tried playing with different channels : no change.
I tried using 2.4 GHz : no change.
Tried turning off power management on the laptop : no change.

For example I tried setting TX power to 5 dBm on both the laptop (using iwconfig) and the router, setting channel width to 20 MHz on a 5 GHz band in A mode (no N, no AC, no AX), only 1 RX chain and only 1 TX chain, moving the laptop around so that I'd get a receive power of about -50 dBm on both the router and the laptop. This should give the most compatible speed reading right? The connection is marked as 54 Mbps. The phone gets a nice stable 25 Mbps down and 25 Mbps up. The laptop with the realtek chip 14 Mbps down and 16 Mbps up. The laptop with the intel chip got 22 Mbps down and 21 Mbps up and it was further away at -65 dBm.


Just puzzling.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 3:45 am

I tried using 2.4 GHz

Unlike ax, ac isn't defined for both 2.4 and 5GHz. You would have fallen down to "n" at best. If it fell down to "g" instead, that would explain your speeds.

Assuming both radios are using the same SSID, I'd try turning on FT mode on them both, giving the laptop its best chance to use its ac capabilities on the 5GHz bands. Otherwise, it is likely to decide the 2.4 GHz band is more powerful, thus a "better" choice.

If that doesn't help, post your wifi configuration. Let's work from data, not guesses, okay?
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 4:17 am

I tried using 2.4 GHz

Unlike ax, ac isn't defined for both 2.4 and 5GHz. You would have fallen down to "n" at best. If it fell down to "g" instead, that would explain your speeds.

Assuming both radios are using the same SSID, I'd try turning on FT mode on them both, giving the laptop its best chance to use its ac capabilities on the 5GHz bands. Otherwise, it is likely to decide the 2.4 GHz band is more powerful, thus a "better" choice.

If that doesn't help, post your wifi configuration. Let's work from data, not guesses, okay?
I tried with 2.4 GHz completely disabled.
With 2.4 GHz completely disabled I tried different modes : A, A/N, AC, AX : no difference whatsoever, can't break the 20 Mbps barrier.
With 2.4 GHz still disabled, I tried different combinations of channel widths : A 20 MHz, A 20/40 MHz, A/N 20 MHz, A/N 20/40 MHz, AC 20 MHz, AC 20/40 MHz, AC 20/40/80 MHz : no difference, still won't break the 20 Mbps barrier.
With 2.4 GHz still disabled, I tried different combinations of modes, widths, TX power settings, chains (tried only chain 0 for both RX and TX, tried only chain 1 for both RX and TX, tried chain 0 for RX and chain 1 for TX, then chain 1 for RX and chain 0 for TX, also using both chains for RX and TX), nothing gets me above 20 Mbps on this specific laptop.
Another laptop (intel wifi chip) gets 300 Mbps with the same hAP ax3, in the same exact position, that this specific laptop (realtek wifi chip) gets 20 Mbps, and the same laptop (realtek wifi chip) gets 150 Mbps on a public hotspot.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 4:24 am

Put the realtek in the real garbage.............
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 4:33 am

I repeat: show your configuration. At minimum, the output of:

/interface/wifi/export

For comparison, here's a boiled-down version of my ax³ config, which gets me near a gigabit right on top of the router with an ax client, and 200-300 Mbit/sec a few rooms away.

/interface wifi configuration
add channel.skip-dfs-channels=10min-cac country="United States" mode=ap name=nunyabinness \
    security.authentication-types=wpa2-psk,wpa3-psk .ft=yes .ft-over-ds=yes ssid="Nunya Binness"
/interface wifi
set [ find default-name=wifi1 ] channel.band=5ghz-ax .width=20/40/80mhz configuration=nunyabinness
set [ find default-name=wifi2 ] channel.band=2ghz-ax .width=20/40mhz    configuration=nunyabinness

If yours is substantially the same, then my suspicion is that we're down to implementation compatibility issues. "Realtek" is a bad sign, and I'm getting the impression that you're talking about a Linux host atop that, where Realtek puts in even less effort than normal.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 4:39 am

I repeat: show your configuration.

Here's my configuration right now:

[admin@MikroTik] /interface/wifi/configuration> print  
Flags: X - disabled 
 0   name="cfg1" mode=ap ssid="**ELIDED**" country=Switzerland 
     security.authentication-types=wpa2-psk,wpa3-psk .group-key-update=30m .passphrase="**ELIDED**" .ft=yes .ft-mobility-domain=0x222 .connect-priority=0 
     datapath.bridge=bridge1 .vlan-id=1 
     steering=steering1 
     steering.neighbor-group=dynamic-home-6185ac38 .rrm=yes .wnm=yes 
Output from iwconfig:

root@asus:~# iwconfig
lo        no wireless extensions.

wlan0     IEEE 802.11  ESSID:"**ELIDED**"  
          Mode:Managed  Frequency:5.2 GHz  Access Point: **ELIDED**   
          Bit Rate=351 Mb/s   Tx-Power=13 dBm   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:on
          Link Quality=47/70  Signal level=-63 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:1  Invalid misc:119   Missed beacon:0
Last edited by tangent on Wed Mar 13, 2024 4:44 am, edited 1 time in total.
Reason: elided PII; trimmed quote
 
ansky
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 4:44 am

More complete:

admin@MikroTik] /interface/wifi/actual-configuration> print  
 0 name="wifi1-5G" l2mtu=1560 mac-address=**ELIDED** arp-timeout=auto radio-mac=**ELIDED** 
   configuration.mode=ap .ssid="**ELIDED**" .country=Switzerland .tx-power=15 
   security.authentication-types=wpa2-psk,wpa3-psk .group-key-update=30m .passphrase="**ELIDED**" .ft=yes .ft-mobility-domain=0x222 .connect-priority=0 
   datapath.bridge=bridge1 .vlan-id=1 
   channel.frequency=5000-5200 
   steering.neighbor-group=dynamic-home-6185ac38 .rrm=yes .wnm=yes 

 1 name="wifi2-2G" l2mtu=1560 mac-address=**ELIDED**  arp-timeout=auto radio-mac=**ELIDED** 
   configuration.mode=ap .ssid="**ELIDED**" .country=Switzerland .tx-power=5 
   security.authentication-types=wpa2-psk,wpa3-psk .group-key-update=30m .passphrase="**ELIDED**" .ft=yes .ft-mobility-domain=0x222 .connect-priority=0 
   datapath.bridge=bridge1 .vlan-id=1 
   channel.width=20mhz 
   steering.neighbor-group=dynamic-home-6185ac38 .rrm=yes .wnm=yes 
[/code}
Last edited by tangent on Wed Mar 13, 2024 4:55 am, edited 1 time in total.
Reason: elided PII
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 4:57 am

One of the reasons I suggested using an /export command instead of /print is that it suppresses sensitive info like your WiFi password by default. I've edited that out of your postings above, but you can't count on us moderators to backstop you like that every single time.

Other than local details like that, I see no meaningful difference between your configuration and mine. You could let some of the values go to defaults instead of the local overrides you have — e.g. I see no reason to override the default mobility domain value on a simple home WiFi gateway setup — but I don't see that that would change anything.

You wanted a new 802.11ax WiFi dongle anyway, right? 😉
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 5:29 am

One of the reasons I suggested using an /export command instead of /print is that it suppresses sensitive info like your WiFi password by default. I've edited that out of your postings above, but you can't count on us moderators to backstop you like that every single time.

Other than local details like that, I see no meaningful difference between your configuration and mine. You could let some of the values go to defaults instead of the local overrides you have — e.g. I see no reason to override the default mobility domain value on a simple home WiFi gateway setup — but I don't see that that would change anything.

You wanted a new 802.11ax WiFi dongle anyway, right? 😉
My laptop has one single USB C port and I can't find a small USB C WiFi 6 dongle. I don't want to use an adapter. I want something small and unobtrusive, that won't break if I apply some force.
Buying another laptop... hard to find one that has WiFi 6, lightweight, touchscreen, works well with linux, very long battery life (I get 9 to 12 hours out of this cheap $350 Asus TP401, with a puny 2 core CPU and 4 GB of RAM), and cheap enough that I don't worry of it being stolen or damaged. With Devuan this laptop works surprisingly well. I have 15 tabs open in firefox right now and RAM usage is 2.72 GB of 3.65 GB available. Just opened the thunderbird email client in parallel and it's 3.14 GB/3.65 GB. The thing has no fans and makes no noise.
Works fine with non-MikroTik wifi. Other devices work fine with the MikroTik AP.
Maybe I'll open it up and see if I can replace the wifi card.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 7:52 am

WiFi 6, lightweight, touchscreen, works well with linux, very long battery life, and cheap enough that I don't worry of it being stolen or damaged.

Sounds like a mid-range Chromebook. Mine manages to push 180 Mbit/sec to the Internet through the ax³ from a few rooms away. It's a 2021 model, so one hopes a current model will do better.

Ironically, this one appears to have a Realtek WiFi 6 radio inside. Difference being, Google has a big, weighted bat to swing around, allowing it to get Linux compatibility issues solved.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 12:01 pm

WiFi 6, lightweight, touchscreen, works well with linux, very long battery life, and cheap enough that I don't worry of it being stolen or damaged.

Sounds like a mid-range Chromebook. Mine manages to push 180 Mbit/sec to the Internet through the ax³ from a few rooms away. It's a 2021 model, so one hopes a current model will do better.

Ironically, this one appears to have a Realtek WiFi 6 radio inside. Difference being, Google has a big, weighted bat to swing around, allowing it to get Linux compatibility issues solved.
I tried booting windows 10 from a usb disk to see what happens. Got 170 Mbps.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 12:23 pm

So title should be changed to "Chromebook with RTL8821CE = bad wifi speed but works normal using Windows"

This is no Mikrotik problem.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 12:55 pm

So title should be changed to "Chromebook with RTL8821CE = bad wifi speed but works normal using Windows"

This is no Mikrotik problem.
Well, the OP reported that even on his Linux, but on non-Mikrotik based wi-fi it works as well fast enough, so there must be some Mikrotik specific setting that is not compatible with the laptop setup/drivers/whatever or viceversa something in the laptop setup/drivers/whatever that is not compatible with Mikrotik (default) settings.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 1:44 pm

I have client devices not behaving on non-MT APs but they work nicely on MT. Where should I complain ?
You can never cover all bases for every possible combination of client devices and access points.

Just have a look at all the Apple-related wifi problems.
Everyone and everything is at fault except Apple ? Yeah right ...

What OP could try is to set everything on that AX3 as minimal as possible (only WPA2 maybe even WPA, no encryption, ...) and then see what happens.
Also separate SSID for 5GHz channel to see if his device connects then to the proper radio.
Yet it does all work nicely with his smartphone or older laptop, yes ?

So IMHO all this is not an AP problem. It's a client problem (client = combination of HW and OS).
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 2:07 pm

Put the realtek in the real garbage.............
I was just trying to remember what gave me so much trouble, just dug it out to take a pic.....
You do not have the required permissions to view the files attached to this post.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 2:22 pm

@holvoeth
I don't think anyone is attempting to blame Mikrotik for the issue, and actually it is rather pointless to blame anyone, there is a problem and this problem should be solved, one way or the other.
If the device (or the Os or the driver) is incompatible with *something* that Mikrotik does (possibly with 100% compliance with any and all RFC's, technical norms and whatnot), the point is to find that *something* and a way to change it so that it works.

It is - as I see it - not unlike the approach used (from what we can see on TV) by the NTSB when an airplane accident happens, the scope is not primarily that of finding a culprit, but rather to find a way to avoid the same accident to happen again.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 2:35 pm

I know where you're going to and still my position is: it depends.

If that workaround implies you have to lower standards in such a way that you simply can not pass anymore between floor and bar, then one should consider the option to simply let go of the offending devices.
You can not keep supporting everything or at a certain point you will not be able to move on.

E.g. I had with an installation on a specific site of a client ONE single device not allowing me to use WPA2 (wifi card of a paint color mixing machine).
Even allowing both options WPA/WPA2 was enough to make it choke. Only WPA was accepted as valid option, nothing else.
I replaced the wifi dongle on that PC and that was it.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 3:55 pm

Here is some more information if it helps debug the issue:
OS: Devuan GNU/Linux 4 (chimaera) x86_64
Host: VivoBook_ASUSLaptop TP401MAR_TP401MA 1.0
Kernel: 5.10.0-27-amd64
CPU: Intel Celeron N4020 (2) @ 2.800GHz
GPU: Intel GeminiLake [UHD Graphics 600]

It's using in kernel driver rtw88_8821ce.

Wifi works fine with non MikroTik hardware. Also works fine under Windows with MikroTik hardware.
I have not tested other linux distributions but if you want me to test it's not a problem, as long as I can boot a live ISO.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 4:08 pm

Linux kernel 5.10 ? That's from ... what, end 2020 ?

There are updates for that RTL8821CE driver going to januari 2024.
I would have a look there first.
Update your drivers.

True story:
new laptop: windows 11 Pro, (also Realtek) ethernet card with normal port and USB.
Couldn't get over 840Mb using ethernet connecting to CSS610 or AX3 (and then iperf server on NAS). Not via ethernet port, not via USB-C port to docking station. I wasn't able to understand why.
Updated drivers directly from supplier and it's humming nicely at 950-ish now.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed  [SOLVED]

Wed Mar 13, 2024 4:43 pm

Yep :) , I concur that "it depends", but "it depends" is different from the initial (perceived) "not a Mikrotik issue, go away".

Let's see if we can find on what exactly "it depends".

Obviously not at the same amplitude level of the (known) Apple issues, but an Asus Vivobook is not a rare device (though likely right now 99% of them are running WIndows and don't have this issue) but it looks like one that will likely be discarded by Windows users and that will fall in the hands of Linux users, not a niche, one-user-only-has-it device, and probably the problem is connected to the wifi card and/or its driver, so it likely extends to all notebooks with that card running Linux.
Replacing the card in a notebook, besides the cost of the new card, can be - depending on the model - a difficult task, if it was a desktop PC I would have suggested to try a new nic first thing, with laptops is not so easy.

@ansky
You should provide a complete configuration export, follow this:
viewtopic.php?t=203686#p1051720
there is still the possibility that the problem lies in some obscure setting in Mikrotik that some experienced user of the forum can spot and that can be changed without compromising your network security and without the sky falling on our heads (tomorrow).

I don't think that a different distro, likely using the same rtw88_8821ce driver, would behave differently, no idea if any other Linux (or - say - BSD) coming in a .iso bootable/volatile form BUT using a different kernel driver actually exists.
Very likely it won't make any difference, but for what it costs trying booting a non-debian derived .iso is something to try.

To recap, possible causes may be:
1) some "default" or "user modified" settings on the Mikrotik side <- if you provide your configuration we can check if anything is blatantly "wrong" in it.
2) some "default" or "user modified" settings on the Linux side <- you should know if you have changed anything and/or you can try resetting to default
3) some "peculiar" setting/behaviour of the driver <- in which case maybe there are other documented cases on Linux dedicated boards/mailing lists/whatever
4) some "peculiar" behaviour of the Asus Vivobook hardware with that driver

If #1 then Windows (or its driver) has a way to workaround it by default
If #2 then all distros will have the same settings and will fail in the same way (so it would be more likely to find similar documented cases)
If #3 it would still seem to me improbable that noone else has already experienced the same issue, Mikrotik devices may be not the most common around, but they are not niche, and as well that Realtek card is not a home made single specimen, but if you are running an older driver I would try latest first thing
#4 seems like the most probable (and also the most difficult to pinpoint/troubleshoot, unfortunately)

P.S.: Check this:
https://forums.linuxmint.com/viewtopic.php?t=394684
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 4:48 pm

I don't think that a different distro, likely using the same rtw88_8821ce driver, ...
A different distro should then also use that same 2020 driver in order to compare apples to apples (yeah, used that one on purpose :lol: ).
Let's have that driver first updated to current version and then we can see how to proceed.
 
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 8:18 pm

That did it. Using driver rtl8821ce instead of rtw88_8821ce.
I got 186 Mbps download and 67 Mbps upload. Still not the 300 Mbps that my other devices are getting but it's acceptable.
Why the problem presents itself only with MikroTik AP combined with the rtw88_8821ce driver is still an open question. Although I can't exclude that the problem may present itself with other routers. I haven't tested all the routers out there.

Edit: using TX power 10 dBm (on the laptop) I got 180 Mbps download and 97 Mbps upload. My WAN is 1 Gbps download and 100 Mbps upload.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Wed Mar 13, 2024 9:08 pm

Edit: using TX power 10 dBm (on the laptop) I got 180 Mbps download and 97 Mbps upload. My WAN is 1 Gbps download and 100 Mbps upload.
So maybe the 180-190 is like the max speed available on that notebook?

I have not understood if on that notebook you are dual booting Windows and Linux, if not testing another notebook (possibly more powerful/with better Wi-FI) running Windows can tell us very little, besides the fact that in the same spot a faster connection is available.

In theory, the RTL8821CE should be a 433 Mbps device, which in practice should max out (in lucky days) around 2/3 of that so - maybe 300 Mbps.

That card/chip (and/or its drivers) are often reported as slowish and/or fluctuating even on Windows (particularly - it seems - on HP laptops).
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Fri May 31, 2024 4:50 am

Good news, the laptop fell from 2 meters and got completely destroyed.
Got myself a new Vivobook TP3402, on which I installed linux mint.
Now it's using an intel wifi adapter with iwlwifi driver.

I did some speed tests in different configurations. All speed tests performed using iperf3 in TCP mode to a server connected by 1 Gbit LAN cable. Only one device connected to the AP (the laptop doing the tests), no interference from neighbors as they are all in much higher channels.
The AP has two 10 dBi antennas, each turned 45 degrees, so 90 degrees between them.

Configuration 1 : 80 MHz width, channel 36, 802.1ax, laptop TX/RX chains 2x2, AP chains 2x2, TX power laptop 20 dBm, TX power AP 17 dBm.
Data rate at 1 meter: 50M down, 577M up, RX signal on laptop -35 dBm, RX signal on AP -40 dBm.
Data rate at 3 meters: 70M down, 409M up, RX signal on laptop -63, RX on AP -60.

Configuration 2 : 40 MHz width, channel 36, 802.1ax, laptop TX/RX chains 2x2, AP chains 2x2, TX power laptop 20 dBm, TX power AP 17 dBm.
Data rate at 1 meter: 167M down, 482M up, RX on laptop -33, RX on AP -37.
Data rate at 3 meters: 160M down, 283M up, RX on laptop -58, RX on AP -58.

Configuration 3 : 20 MHz width, channel 36, 802.1ax, laptop TX/RX chains 2x2, AP chains 2x2, TX power laptop 20 dBm, TX power AP 17 dBm.
Data rate at 1 meter: 127M down, 226M up, RX on laptop -27, RX on AP -31.
Data rate at 3 meters: 140M down, 203M up, RX on laptop -55, RX on AP -54.

Lets try only one TX chain on the AP and less power:
Configuration 4 : 40 MHz width, channel 36, 802.1ax, laptop TX/RX chains 2x2, AP chains 1x2, TX power laptop 0 dBm, TX power AP 1 dBm.
Data rate at 1 meter: 111M down, 199M up, RX on laptop -48, RX on AP -36.
Data rate at 3 meters: 110M down, 159M up, RX on laptop -64, RX on AP -63.

Strange that dropping power by 20 dB did not result in a 20 dB decrease at 3 meters. I could understand at 1 meter there could be shenanigans with the wave not being fully formed. Maybe the laptop is not honoring my power settings.
All I can tell from this test is that 80 MHz sucks, and that I can comfortably decrease power, and fry my brains a little less.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Fri May 31, 2024 10:40 am

When testing with iperf3: don't forget to test with "-R" flag too. This way the iperf3 server sends data to the client, meaning you are benchmarking AP download speed to client. without -R flag you measure the client UPLOAD performance, which is wayyyyyy limited by client device antenna/driver/hardware. And I have one Intel AX200 card running on Manjaro Linux as well, and that driver or card is a bit*h. Upload is a subpar (high retransmission rate).
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Fri May 31, 2024 11:10 am

When testing with iperf3: don't forget to test with "-R" flag too. This way the iperf3 server sends data to the client, meaning you are benchmarking AP download speed to client. without -R flag you measure the client UPLOAD performance, which is wayyyyyy limited by client device antenna/driver/hardware. And I have one Intel AX200 card running on Manjaro Linux as well, and that driver or card is a bit*h. Upload is a subpar (high retransmission rate).
That's how I measured the download speed.
 
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Fri May 31, 2024 11:43 am

ax200, 201, 210 and 211 cards are regularly downloading + uploading over 700Mbit/s from AX3 on Windows 10/11 from internet, not on local network with iptraf tests (=that must be more.

Even shitty Realtek AX wifi cards can do that. I suspect those linux drivers and/or plethora of configuration options either on Linux side, or Mikrotik.

It's not sufficient just to configure 80MHz and expect miracles.

You wrote something about 10dBi antennas. Are those Mikrotik standard ? My personal experience : when I replaced original AX3 antennas with "bigger better stronger" DLink 9dbi models (something like https://www.ebay.com/itm/112387385667 ) the real throughput was decreased by 50%. Those antennas are simply trash. I didn't change anything in configuration, just replaced antennas.

I think the same really applies to your 10dBi antennas.

Next, turn down 20dBm power on laptop : you don't need that and it's harmful for ISI (intersymbol interference) of wifi. RECEIVE LEVELS OVER -50DBM UNNECESSARILY OVERLOAD ANALOG AMPLIFIERS AND MAKE YOUR THROUGHPUT WORSE, WHILE SHORTENING LIFESPAN OF YOUR DEVICES. It's too much noise, not too much music. That's a difference. You don't need -31dBm receive signal, you don't want it. IT'S BAD.

Take it slow. Keep it simple. No datapath. No steering. Nothing. WHO ADVICED YOU FREQUENCIES 5000-5200 ? Why 5000 ? No radio, no antenna, no device has been tuned to use that, not talking about AX200 unable to use those frequencies. You don't need anything less than 5160. You should not try to use.

Greetings to beautiful Alpine country !
 
ansky
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Fri May 31, 2024 8:54 pm

ax200, 201, 210 and 211 cards are regularly downloading + uploading over 700Mbit/s from AX3 on Windows 10/11 from internet, not on local network with iptraf tests (=that must be more.

Even shitty Realtek AX wifi cards can do that. I suspect those linux drivers and/or plethora of configuration options either on Linux side, or Mikrotik.

It's not sufficient just to configure 80MHz and expect miracles.

You wrote something about 10dBi antennas. Are those Mikrotik standard ? My personal experience : when I replaced original AX3 antennas with "bigger better stronger" DLink 9dbi models (something like https://www.ebay.com/itm/112387385667 ) the real throughput was decreased by 50%. Those antennas are simply trash. I didn't change anything in configuration, just replaced antennas.

I think the same really applies to your 10dBi antennas.

Next, turn down 20dBm power on laptop : you don't need that and it's harmful for ISI (intersymbol interference) of wifi. RECEIVE LEVELS OVER -50DBM UNNECESSARILY OVERLOAD ANALOG AMPLIFIERS AND MAKE YOUR THROUGHPUT WORSE, WHILE SHORTENING LIFESPAN OF YOUR DEVICES. It's too much noise, not too much music. That's a difference. You don't need -31dBm receive signal, you don't want it. IT'S BAD.

Take it slow. Keep it simple. No datapath. No steering. Nothing. WHO ADVICED YOU FREQUENCIES 5000-5200 ? Why 5000 ? No radio, no antenna, no device has been tuned to use that, not talking about AX200 unable to use those frequencies. You don't need anything less than 5160. You should not try to use.

Greetings to beautiful Alpine country !


The AP is in the corner of a house. There is no need for the signal to go outside the walls to the freeloading neighbors. I'm using the Alfa 10 dBi directional https://www.alfa.com.tw/products/apa-m2 ... 1664232520
 
jaclaz
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Sat Jun 01, 2024 2:30 am

Good news, the laptop fell from 2 meters and got completely destroyed.
Empirical testing of maxim eleven? :shock:

https://www.schlockmercenary.com/2008-12-11
 
mp3turbo
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Sat Jun 08, 2024 10:22 pm

>> The AP is in the corner of a house. There is no need for the signal to go outside the walls to the freeloading neighbors.

why do you use stronger antennas than ? 10dBi is much more than ~5dBi original sticks that came from factory.
Next, if you want weaker signal, you can easily turn down TX Power.

.

>> I'm using the Alfa 10 dBi directional https://www.alfa.com.tw/products/apa-m2 ... 1664232520

I'm pretty sure this antenna is the reason for your low and erratic throughput. These "I can do everything" antennas in reality can't do anything properly.
Replace with Mikrotik originals that came with AX3. Easy to try, doesn't cost anything.

Don't forget to power off Mikrotik AX3 before physically unmounting antennas ! Never change antennas on device which is powered on.



edit : from website you linked

8 dBi @ 2.4 – 2.5 GHz
10 dBi @ 5.150 – 5.875 GHz
9 dBi @ 5.975 – 7.125 GHz

now I instantly know this "antenna" is a lie. Blatant lie. Its physical dimensions plus these numbers tell all the story.
Throw it away.
 
ansky
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Re: hAP ax3 + Realtek RTL8821CE 802.11ac = bad wifi speed

Sun Jun 09, 2024 12:45 am

>> I'm using the Alfa 10 dBi directional https://www.alfa.com.tw/products/apa-m2 ... 1664232520

I'm pretty sure this antenna is the reason for your low and erratic throughput.
I tested the antenna with a VNA and I can confirm that it's radiating well. As for directionality, I haven't tested that extensively but the antenna is directional and none of the signal makes it outside the house.