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Comment by vlan0 | Hacker News Reader

I don't understand what possesses these folks to continue making 2.4ghz devices. I understand there are use cases for low bandwidth, high range. But surely we've passed the point where that is more desirable to most than lower latency and high throughput, right?

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> I understand there are use cases for low bandwidth, high range.

Use cases like IoT? The very thing this is for?

Is what you described a truth for all IoT devices? If I have los of my AP, why do I need 2.4Ghz? Even so, what SNR do you truly need for this low bandwidth application? Where is the engineering here?

I have a unique position of having a data set over 8000 APs with 40k unique devices. If you design properly, there is no need for 2.4 ever. 2.4Ghz congestion (with nearly no actual 802.11 traffic) is very high. To the point where the IoT folks are struggling.

2.4 GHz has the advantage of it passing through obstacles easier. The higher the frequency the more easily it gets blocked.

Yes. And 2.4 lives and dies by that sword. What downsides might there be in areas where dozens of APs hear each other and 100s of clients hear each other?

It's an IoT device, not a laptop. It does not really need 5ghz to fulfill its purpose as an embedded CPU, and adding 5ghz likely would require making some room for it by removing other functionality.

Yes and in some uses cases it works against you. 2.4 is incredibly crowded without adding 802.11 to the mix. My IoT admins would have less complaints if they could take advantage of my small cell 5Ghz spectrum. This isn't 2005 with widely deployed asymmetrical wireless networks.

Can't you just underpower the antenna on a 2.4 radio if you need networks that don't bleed into each other as badly? Unless it's an issue because of the tiny antennas that usually come on microcontrollers.

True for devices under your control. But think venues with large BYOD counts. Add in that all client devices generally transmit at full power. End result is an environment with not a lot of headroom in the 2.4 space.

2.4ghz isn't the only problem - even cell towers have problems with large amounts of devices. And "large BYOD" events are not a normal use case for wireless, and even 5GHz will have problems in those situations.

Right, so RF issues will possibly exist on all frequencies. And yet we continue to build devices on the most congested spectrum available.

I use ESP32s extensively. I also use wifi extensively around the house - I have about 8 wifi access points around the property, with a ton of commercial IoT stuff powered on including sensors, lights, cameras, you name it, I got it. It's about as wifi-congested as any house can get.

So, I was measuring about 250KBit/s on an ESP32, and I decided to test everything that might increase the speed. I tried all the available antenna options for the ESP32 including many exotic antennas using the IPEX antenna connector variant of the ESP32, the stock ESP32 pcb antenna, and several chip antennas. A couple of them got up to 300KBit/s.

I also decided to see what happens when I power everything else off except for a single wifi router. So I did that, and I found that the stock ESP32 pcb antenna still got only 250KBit/s, and the other antennas measured exactly the same as they did before shutting everything down, too.

So, I don't know... 2.4ghz seems fine to me from my anecdotal tests.

My 2.4ghz is basically all IOT these days. Things that matter are on 5 or 6 ghz. Busy moving the entire thing to be entirely firewalled off given how clean the separation is

>My 2.4ghz is basically all IOT these days.

Yup. And it's exactly why some of my IoT admins are struggling. There is only so much spectrum to go around.

Don't think you're ever going to reclaim that spectrum successfully. There must be billions of devices on it. Pretty much any other ghz number is a better bet

Yup, and here we are continues to pile on.

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