Issues with 5GHz network

Zedshi

Reputable
Oct 18, 2016
24
0
4,510
Hi.
My router has both 2,4Ghz and 5GHz, but on my pc it only shows 2,4GHz as available. I did the cmd check "netsh wlan show drivers", and my pc should support it, this is what I got:

Radio types supported : 802.11ac 802.11a 802.11n 802.11g 802.11b

I have the Asus pce-ac68, which should also support it.

I tried going into disk manager then into advanced settings for my adapter, but nothing there helps me. What do I do to access my 5GHz network?

My brother also has the same network adapter, and he is able to connect to the 5GHz network.
 
Solution

802.11ac is 5 GHz-only. So if your radio supports 802.11ac, then it supports 5 GHz.

The most common reason I've seen for this problem (one computer can see the 5 GHz network, another cannot) is due to something called DFS. The short answer is to manually set your router to only use 5 GHz channels 36-48 or 149-165. If it's set to auto-select the channel, it may be using channels between 50-144.

https://en.wikipedia.org/wiki/List_of_WLAN_channels#5_GHz_(802.11a/h/j/n/ac/ax)

The long answer is that soon after the FCC opened up the 5 GHz band, it was discovered that some of the frequencies right in the middle of it were useful for a new form of doppler...

802.11ac is 5 GHz-only. So if your radio supports 802.11ac, then it supports 5 GHz.

The most common reason I've seen for this problem (one computer can see the 5 GHz network, another cannot) is due to something called DFS. The short answer is to manually set your router to only use 5 GHz channels 36-48 or 149-165. If it's set to auto-select the channel, it may be using channels between 50-144.

https://en.wikipedia.org/wiki/List_of_WLAN_channels#5_GHz_(802.11a/h/j/n/ac/ax)

The long answer is that soon after the FCC opened up the 5 GHz band, it was discovered that some of the frequencies right in the middle of it were useful for a new form of doppler weather radar that was better at detecting downbursts, which is a weather phenomenon lasting a few minutes that has caused several airliner crashes. It's used predominantly at certain U.S. airports which frequently suffer bad weather, but is showing up in more airports worldwide.

Anyhow, 5 GHz WiFi transmissions at these frequencies can completely destroy the effectiveness of this doppler weather radar. So the FCC took the unusual step of going back and putting new restrictions on the frequencies it had already declared as open. The interfering frequencies fell within channels 50-144. The FCC reclassified them as DFS - dynamic frequency selection. A 5 GHz device may use these channels, but if it does it must monitor for weather radar. If it detects weather radar in use, it must automatically switch to a different non-DFS channel.

A few WiFi device makers did just this. Their devices can use all 5 GHz channels from 36-165. But if it's using 50-144 and it detects weather radar, it will automatically switch to 36-48 or 149-165.

Most WiFi device makers didn't bother checking for weather radar. Their devices are blocked in their firmware from ever using channels 50-144.

The situation you're experiencing happens when your router supports DFS and has selected a channel in the 50-144 range for its 5 GHz network. A device with a WiFi adapter which supports DFS can connect to this router at 5 GHz. But a device with a WiFi adapter which has blocked the DFS channels cannot see the 5 GHz network. Manually setting the router's 5 GHz channel to 36-48 or 149-165 puts the 5 GHz network on a channel that both WiFi adapters can see.
 
Solution

Zedshi

Reputable
Oct 18, 2016
24
0
4,510


Wow thank you for a very in depth explanation! I will try to figure out how to change it to 36-48 or 149-165.