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rtho782 · 26-08-2018, 19:50

So half the problem is that advertised wifi speeds are a joke.

2.4ghz only supports 802.11n, so with 1 antenna (a single stream) 150mbit is the maximum, but in practice it's more like 50-60mbit. I'm pretty sure the SH3 has 2 streams in 2.4ghz so max is 300mbit, the reality much lower.

5GHz supports 802.11ac but only if your device does. The SH3 supports 3 streams in this mode, which means 1300mbits, but there are close to zero client devices that support 3x3 MIMO. I think some of the Macbook Pros do, but not all, and that's about it.

This means that the BEST link speed from 802.11ac with most devices is 866mbit. Still sounds like plenty right?

Until your wife's old phone that only supports 802.11n on 5ghz in a single stream is downloading at 10mbit. That might easily use up 15% of the airtime, reducing the bandwidth for you by 15%.

Added to that, the access point itself cannot determine which frequency a client connects to, that is entirely up to the client. Even the ubiquti kit - which has an option to steer clients to 5GHz, does this simply by booting them off 2.4GHz if it thinks they support 5Ghz, and if they stay on 2.4ghz gives up.

VM have tested the wifi on the SH3, but don't forget it's an old device now. They tested it against a Homehub 4, which didn't even have 802.11ac. They also likely tested it in a mock house with only stud walls and no insulation between the plasterboard panels.

Your iphone 6 could easily be connected on 2.4ghz, where it is never going to achieve miraculous speeds. In fact, the iphone 6 only supports single stream in either 2.4ghz or 5ghz, and so that means 433mbit link speed on a perfect 802.11ac connection.

Given that you likely don't have a perfect connection, and there is a good chance that you are not using 40mhz not 80mhz channels, which halves your max link speed to 216mbit, there is every chance you are not going to see a perfect connection.

Added to this, routers and devices are advertised as "900mbit" if they support 450mbit on each band - which is clearly a lie as they can't connect to both at once.

In any case, if you really want good wireless performance, invest in 2x2 MIMO kit (e.g. not an iphone 6, the Oneplus 5T I have does it fine for example) and put up some proper access points, ubiquiti or similar.

26-08-2018, 19:50	#13
rtho782 cf.addict Join Date: Nov 2016 Posts: 310	Re: Virgin Media Figures So half the problem is that advertised wifi speeds are a joke. 2.4ghz only supports 802.11n, so with 1 antenna (a single stream) 150mbit is the maximum, but in practice it's more like 50-60mbit. I'm pretty sure the SH3 has 2 streams in 2.4ghz so max is 300mbit, the reality much lower. 5GHz supports 802.11ac but only if your device does. The SH3 supports 3 streams in this mode, which means 1300mbits, but there are close to zero client devices that support 3x3 MIMO. I think some of the Macbook Pros do, but not all, and that's about it. This means that the BEST link speed from 802.11ac with most devices is 866mbit. Still sounds like plenty right? Until your wife's old phone that only supports 802.11n on 5ghz in a single stream is downloading at 10mbit. That might easily use up 15% of the airtime, reducing the bandwidth for you by 15%. Added to that, the access point itself cannot determine which frequency a client connects to, that is entirely up to the client. Even the ubiquti kit - which has an option to steer clients to 5GHz, does this simply by booting them off 2.4GHz if it thinks they support 5Ghz, and if they stay on 2.4ghz gives up. VM have tested the wifi on the SH3, but don't forget it's an old device now. They tested it against a Homehub 4, which didn't even have 802.11ac. They also likely tested it in a mock house with only stud walls and no insulation between the plasterboard panels. Your iphone 6 could easily be connected on 2.4ghz, where it is never going to achieve miraculous speeds. In fact, the iphone 6 only supports single stream in either 2.4ghz or 5ghz, and so that means 433mbit link speed on a perfect 802.11ac connection. Given that you likely don't have a perfect connection, and there is a good chance that you are not using 40mhz not 80mhz channels, which halves your max link speed to 216mbit, there is every chance you are not going to see a perfect connection. Added to this, routers and devices are advertised as "900mbit" if they support 450mbit on each band - which is clearly a lie as they can't connect to both at once. In any case, if you really want good wireless performance, invest in 2x2 MIMO kit (e.g. not an iphone 6, the Oneplus 5T I have does it fine for example) and put up some proper access points, ubiquiti or similar.