160 MHz stability

[ColinTaylor]

Thanks for the clarification regarding the US, I didn't know that. I just assumed every country used the same weather radar frequencies as the UK/EU.

Specs say Channel Availability Check (CAC) must be "at least" 60 seconds in US and EU.

Yes, I was being lazy and omitted the "at least" because I thought that was obvious. But that's not the same for the EU.

The 10 minute CAC is required only in Canada and Australia and only for 5600-5650 MHz.

It's also the case in the UK & EU as seen in the chart in post #20 (5600-5650MHz being TWDR covering channels 120-128). See Table D.1, NOTE 1 of EN 301 893.

 

[eibgrad]

All the gory details aside, I'd say it's safe to say that 160MHz (and DFS) is a minefield of issues, and best avoided unless you live in a very remote area. When I see stuff like this, I just shake my head and wonder why even bother. What a headache. Can't help but wonder if sometimes the OEM would be better off to NOT offer the option, esp. if it's only going to serve a select few. And esp. when these devices are intended for the network-challenged masses.

JMTC

 

[Tech Junky]

very remote area

I'm in a metro area w/ 2 airports N/S of me and don't have any issues with my AP with mature FW.

Now, with other devices though there seemed to be more interference with DFS hitting me daily and kicking down to 80mhz channels. Anything RF changes constantly though from the station to how the weather affects the signals being transmitted further and so on.

Going into 160mhz with knowledge of the environment needs to be a key factor in whether or not you'll be able to consistently use it or not. If you don't currently have a device that can consistently work on 160 then getting another might have the same issue. If you don't have one to test with then make sure you have a good return policy for when it's not stable during testing.

 

[heysoundude]

Thanks for the clarification regarding the US, I didn't know that. I just assumed every country used the same weather radar frequencies as the UK/EU.

I believe that will eventually have to happen (global standardisation), but the differences stem from (IIRC, which I likely don't) mains power frequency differences.
I'll try to dig up where I saw that and post for everyone's consideration

 

[ColinTaylor]

but the differences stem from (IIRC, which I likely don't) mains power frequency differences.

Very unlikely to be the case.

 

[heysoundude]

All the gory details aside, I'd say it's safe to say that 160MHz (and DFS) is a minefield of issues, and best avoided unless you live in a very remote area. When I see stuff like this, I just shake my head and wonder why even bother. What a headache. Can't help but wonder if sometimes the OEM would be better off to NOT offer the option, esp. if it's only going to serve a select few. And esp. when these devices are intended for the network-challenged masses.

JMTC

double edged sword: not offering the option when it's available will get as much grumbling/aggravation from users (because someone will eventually go and pull the specs) as we're seeing here about whether to use it or not.

But I agree it's for people who have very fast connections and are way out in the sticks and/or are well off the beaten path. I'm not sure those conditions align commonly - not in my country at least.

 

[heysoundude]

Very unlikely to be the case.

You've broadcast/RF engineering credentials now too?
Do please enlighten us as to why I'm likely mistaken and save me the time of digging through my bookmarks

 

[ColinTaylor]

You've broadcast/RF engineering credentials now too?
Do please enlighten us as to why I'm likely mistaken and save me the time of digging through my bookmarks

I've been a licenced radio amateur since the 1970's and my first job was as an electronics engineer.

I said I thought it was unlikely there was a connection between the local mains frequency (60 Hz) and the weather radar bands (5600-5650 MHz). Especially as both the US and Canada use 60 Hz mains. But I'm more than happy for you to post a link to something that I haven't taken into consideration so that I can learn something new.

 

[Clark Griswald]

Just an observation:
Sadly, there seems a large amount of nontechnical instability in this stability thread.

 

[Tech Junky]

Something else comes to mind and that's TV stations that may be broadcasting nearby as well.

 

[Tech9]

You've broadcast/RF engineering credentials now too?

I used to build all kind of electronic devices from analog light barrier alarm systems, audio amplifiers, spectral analyzers to radio receivers and long range radios, all working with various frequencies and mains power frequency was never an issue and was never related to the device’s operation. None of those devices is powered by AC. I would like to know the connection between mains frequency and radars as well, if possible.

@octopus may know something about the subject.

 

[sfx2000]

I said I thought it was unlikely there was a connection between the local mains frequency (60 Hz) and the weather radar bands (5600-5650 MHz). Especially as both the US and Canada use 60 Hz mains.

There's no correlation between the grid frequency (50/60Hz) and TWDR operation, including PRF and other items as @ColinTaylor mentions...

I'm also a license holder, and I've done a fair amount of work in the field (in fact, my whole career has been involved in wireless at several key nodes - from mobile handsets, base station design, core networks, standards (802.11, 802.16).

The test cases for DFS are clear, as are requirements from FCC and EU (along with other regulatory agencies, but generally they follow FCC/EU with exceptions for Japan, China, and Israel). Implementations might differ, but they all need to meet requirements.

In the field, at least in regulatory domains that follow DFS-FCC rules, 160MHz in 5GHz will need to do DFS - no way around it without running afoul of regulatory approvals.

There are ways to be clever about it, one being scanning for existing AP's that are already in DFS and transmitting, but one still has to do the periodic scans for radars...

 

[sfx2000]

I'm in a metro area w/ 2 airports N/S of me and don't have any issues with my AP with mature FW.

One of my local TV broadcasters has a 5GHz TWDR, so when they fire it up during weather events (as rare as they are here in SoCal), I see most my AP's jump away and go into ACS/DFS triage...

That being said - I've seen some implementation only do the scan on startup - which is buggy and no really consistent with the intent of the DFS rules - it's supposed to be an ongoing thing.

This makes 160MHz in 5GHz a bit of a challenge, obviously...

 

[RMerlin]

In the field, at least in regulatory domains that follow DFS-FCC rules, 160MHz in 5GHz will need to do DFS - no way around it without running afoul of regulatory approvals.

Opening access to the UNII-4 band may finally allow non-DFS 160 MHz channel use in the US at least. Asus is adding that band in some of their new models.

 

[sfx2000]

Opening access to the UNII-4 band may finally allow non-DFS 160 MHz channel use in the US at least. Asus is adding that band in some of their new models.

Challenge there is client silicon - not all radio's can be upgraded, and there may be some RF front-end mismatch for existing radios that could be upgraded...

I think Syno's new router supports it (RT6600ax), and maybe Asus GT-AX11000 Pro

 

[sfx2000]

One of the other implementation things that can be "interesting" is that to get to 160MHz wide channels, some radios will drop from 4*4:4 to 2 streams - which may negate the advantage of using wide channels - I would see this more for Wireless Bridges and/or WiFi backhaul in Mesh/WDS applications - but that is a consideration - probably more for the older 802.11ac radios vs. current 802.11ax silicon.

The other thing with 160MHz channels is the 3dB loss compared to 80MHz - that's physics, and a 3dB hit on the link budget is significant - performance drop over range is a thing that people care about...

(secret tip - to improve performance in mid-range to long-range, consider using 40MHz channels in 5GHz, getting a 3dB boost to the link budge there for Tx and Rx, it's enough that one can be in coverage or not)

 

[RMerlin]

Challenge there is client silicon - not all radio's can be upgraded, and there may be some RF front-end mismatch for existing radios that could be upgraded...

Right, we can't even confirm at this time if Intel`s AX210 supports it or not. And considering how few regions have opened access to that band, it might be more a marketing thing than an actual feature, and people in need of 160 MHz bandwidth might be better of going Wifi 6E.

 

[Protos]

Why don't you go back to official firmware and if it is not working for you then complain to Asus? I just don't get people like you.
Did you report it to Asus? If not then do it.

I made a post about that but apparently it was deleted. Some thin thin skins in here. Egos on max.
The usual suspects got a little butthurt .....
I also do not get people like you either .... too much feminine energy for me deal with I guess.
This is support 'forum' look up the meaning of that word. https://www.merriam-webster.com/dictionary/forum

 

[sfx2000]

Right, we can't even confirm at this time if Intel`s AX210 supports it or not. And considering how few regions have opened access to that band, it might be more a marketing thing than an actual feature, and people in need of 160 MHz bandwidth might be better of going Wifi 6E.

Yep, and the UNII-4 extension is of little use, as most clients will not be able to use it - looking forward a couple of years, yes, any additional spectrum is welcome, but for now, it's a marketing bullet on a datasheet/product box...