two APs on 20mhz channel in 2.4 or one AP on a 40mhz channel?

given the same signal customers and signal strength. What will move more bandwidth overall two APs on 20mhz channel in 2.4 or one AP on a 40mhz channel in 2.4ghz?

We are considering option for a site that is starting to be congested.

40mhz won’t work on congested environment.

So your saying the AP being congested has more to do with the AP hardware iteself then it does with the amount of frequency it has to work with?

I was hopeing one of the Cambium people would have chimed in by now on this.

Two different forms of congestion is being talked about here I believe. Radio frequency congestion, noise in the spectrum. 40mhz wide channels are much more susceptible to noise related issues than 20 MHz channel. I believe your question was about network congestion. 2 points to consider with that. The sum of the possible​ data rates of 1 40 MHz channel and 2 20mhz channels are the same. IF there is absolutely no noise, you’ll get a like performance assuming the cpes are able to hold the same modulation rates. In real world, you’ve got much better odds of holding higher modulations with narrow channels.

Using a 40mhz channel your minimum rssi and snr needs are slightly higher per code state than in 20mhz.

The more devices you connect to an AP, the higher your total latency can get.

In the event sever noise happens in a single 40mhz channel, all of your customers would be hit. If you’re using two 20 MHz channels, those subs may move over and be slowed down instead of stopped.


So we ended up hanging a second ePMP 2.4 AP at the site an have moved the origional AP back off 40mhz to 20 mhz and configured the second AP on 20mhz as well. Different frequencies obviously. we have off loaded about 25% of the SMs off the first AP to the second and have been monitoring. It apears the hardware was the restriction in our case. The first AP just could not move all the traffic it seemed to stop at about 30mbps. Now that the second is in place we are seeing more throughput when combined and customers experiances are much better.

Just thought I would update this incase anyone was wondering or considering the same options.

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