[SOLVED] 2.4 GHz channels weak on my WAPs

[njitgrad]

All four of my WAPs are giving me very low download speeds (< 5 Mbps) on the 2.4 GHz channels but the 5 GHz channels are good (>100+ Mbps).....as measured by the SpeedTest.Net app on my Galaxy S9 phone. Can anyone tell me a possible cause of the problem and potential solution? I have TrendNet WAPs.

 

[BuddhaSkoota]

All four of my WAPs are giving me very low download speeds (< 5 Mbps) on the 2.4 GHz channels but the 5 GHz channels are good (>100+ Mbps).....as measured by the SpeedTest.Net app on my Galaxy S9 phone. Can anyone tell me a possible cause of the problem and potential solution? I have TrendNet WAPs.

It could be congestion, but since it is affecting 4 APs, I think it's more likely caused by interference from other APs operating on the same or adjacent channels, or from some other electronic source.

I suggest first to check that your APs are operating on different channels that are spaced evenly across the available spectrum.

You can also use an app like Wifi Analyzer to see if there are other neighboring networks using the same channels, and try to avoid any particularly strong signals from those networks.

 

[njitgrad]

All four of my WAPs are giving me very low download speeds (< 5 Mbps) on the 2.4 GHz channels but the 5 GHz channels are good (>100+ Mbps).....as measured by the SpeedTest.Net app on my Galaxy S9 phone. Can anyone tell me a possible cause of the problem and potential solution? I have TrendNet WAPs.

It could be congestion, but since it is affecting 4 APs, I think it's more likely caused by interference from other APs operating on the same or adjacent channels, or from some other electronic source.

I suggest first to check that your APs are operating on different channels that are spaced evenly across the available spectrum.

You can also use an app like Wifi Analyzer to see if there are other neighboring networks using the same channels, and try to avoid any particularly strong signals from those networks.

Here are my settings:

WAP 1 - Channel 1 for 2.4 GHz, Channel 36 for 5.0 GHz
WAP 2 - Channel 2 for 2.4 GHz, Channel 40 for 5.0 GHz
WAP 3 - Channel 3 for 2.4 GHz, Channel 44 for 5.0 GHz
WAP 4 - Channel 4 for 2.4 GHz, Channel 48 for 5.0 GHz

As an experiment I changed the channels as follows:

WAP 1 - Channel 1 for 2.4 GHz
WAP 2 - Channel 3 for 2.4 GHz
WAP 3 - Channel 5 for 2.4 GHz
WAP 4 - Channel 7 for 2.4 GHz

I then checked the speeds with SpeedTest and got the following pathetic results:

WAP 1 - 13 Mbps download, 32 Mbps upload
WAP 2 - 2 Mbps download, 17 Mbps upload
WAP 3 - 2 Mbps download, 14 Mbps upload
WAP 4 - 3 Mbps download, 14 Mbps upload

Yes my upload speeds are faster than my download speeds. I don't get it.

I installed the WiFi Analyzer app but I don't know how to make use of the readings I see.

 

[BuddhaSkoota]

I installed the WiFi Analyzer app but I don't know how to make use of the readings I see.

This page specifically is useful in seeing if there are APs in the vicinity that might be overwhelming the signals of your own APs on similar channels. You should adjust your own channels to avoid ones that are occupied, especially neighboring ones with strong signals.

 

[Solandri]

WAP 1 - Channel 1 for 2.4 GHz, Channel 36 for 5.0 GHz
WAP 2 - Channel 2 for 2.4 GHz, Channel 40 for 5.0 GHz
WAP 3 - Channel 3 for 2.4 GHz, Channel 44 for 5.0 GHz
WAP 4 - Channel 4 for 2.4 GHz, Channel 48 for 5.0 GHz

The 2.4 GHz channels are not independent. Each "channel" actually uses frequencies which covers about 5 channels worth of frequencies. So channel 1 actually covers frequencies used by channels 1-5. Channel 6 covers frequencies used by channels 6-10. Channel 11 covers frequencies used by channels 11-15.

So if you're going to set up multiple 2.4 GHz WAPs with minimum overlap, you want them on channels 1, 6, and 11. Since you have a 4th one, try putting it so it straddles two of these three. e.g. Channel 3 (which will use frequencies used by channels 3-8, and interfere party with channel 1 and channel 6).

5 GHz doesn't have this problem. Each of its channels are fully independent of the others (which is why the channel numbers often jump by 2 or 4).

https://en.wikipedia.org/wiki/List_of_WLAN_channels

 

[njitgrad]

So what I did was disable the 4th WAP and set the channels of the remaining three WAPs to be 1, 6, and 11 as recommended by Solandri.

No change in results.

What I did next was interesting to say the least...I ran SpeedTest on my Galaxy Tab S2 tablet and it gave me greater than 50Mbps download and about 30 Mbps upload for all three WAPs. When I went to run it on my phone again I still got the same paltry numbers that I received earlier. I made sure I had the latest version of the app on both devices.

So which one do I trust? And why is my phone giving me such low data rates at 2.4 GHz?

 

[Solandri]

So what I did was disable the 4th WAP and set the channels of the remaining three WAPs to be 1, 6, and 11 as recommended by Solandri.

No change in results.

I was betting you had a neighbor on channel 1-5 who was interfering with all your WAPs since you'd put them on channels 1, 2, 3, 4. Apparently that wasn't the cause. It's still a good idea to have them spaced 1, 6, 11 though.

What I did next was interesting to say the least...I ran SpeedTest on my Galaxy Tab S2 tablet and it gave me greater than 50Mbps download and about 30 Mbps upload for all three WAPs. When I went to run it on my phone again I still got the same paltry numbers that I received earlier. I made sure I had the latest version of the app on both devices.

So which one do I trust? And why is my phone giving me such low data rates at 2.4 GHz?

There are some router/WAP and device combinations which result in poor performance. I've never figured out an exact cause - probably slight incompatibilities between their implementation of the 802.11 specs. You don't give the model of your WAP, but the second negative review for this TrendNet WAP suggests a problem with Samsung TVs. Wouldn't be too far-fetched that Samsung phones might also be affected.

https://www.amazon.com/TRENDnet-1300Mbps-Repeater-Steering-TEW-825DAP/product-reviews/B01N0SU08T

You could check to see if a firmware update is available for the WAPs. You might also want to check your phone's speed on other 2.4 GHz networks. Could be a bad 2.4 GHz antenna on the phone.