my wifi throutput internet stuck in 20Mbps

[abd qayyum]

when i speed test my connection using wifi thorutpot sppeed stuck in 20Mbps but when i using LAN my speedtest get 80Mbps , i using cisco embended wireless controller, my AP series 9115AXI-F

[Leo Laohoo]

What is the wireless NIC that was used to test the WiFi? 
And what is the driver version of the wireless NIC used to test the WiFi?

[abd qayyum]

i use my windwos 10for use wifi 

the driver version intel(R) Dual band WIreless-AC-3165

[Rich R]

Does Windows 10 have all available Windows Updates installed?

Intel(R) Dual band WIreless-AC-3165 is the model of WiFi network adaptor, not the driver version!
The driver version should be 19.51.40.1 on Windows 10 32-bit or 19.51.50.2 on Windows 10 64-bit
https://www.intel.com/content/www/us/en/download/823059/823060/intel-wireless-wi-fi-drivers-for-wireless-ac-7265-rev-d-3168-and-3165.html

[abd qayyum]

the driver version 19.51.15.3 windwos 10 64-bit

[Rich R]

> driver version 19.51.15.3 windwos 10 64-bit
So update the driver to 19.51.50.2 which you can download from the Intel link above.

[Rich R]

- What version of software are you using on the EWC?

- What band (2.4GHz or 5GHz) was the client connected to during the test?

- How is the WLAN configured?

- Have you checked your config with the config analyzer (link below)

[abd qayyum]

version EWC Cisco Embedded Wireless Controller on Catalyst Access Points 17.9.4

i active in 2.4 n 5G in my PC

i use wifi analyzer for check the signal

yes i use 

[Rich R]

You have 8 SSIDs (WLANs) configured - you should reduce this number if possible, as each additional SSID adds additional overhead to the channel utilisation.  For example Meraki recommend a maximum of 3 SSIDs:
https://documentation.meraki.com/MR/Wi-Fi_Basics_and_Best_Practices/Multi-SSID_Deployment_Considerations

[Leo Laohoo]

Intel AC-3165 is only a 1x1:1.  The best it could do would be around 75 Mbps in 5.0 Ghz. 

At 2.0 Ghz, around 20 Mbps.

[abd qayyum]

yes i have been test when i turn off my SSID 5G the speedtest just get 20Mbps but wehen i use  just 5G the bandwitch get 75 Mbps?

[Leo Laohoo]

It is "the best" the wireless NIC of the laptop can do. 

If your laptop's CPU and memory can handle it, get a WiFi dongle that has higher throughput/capability.

[JPavonM]

• How many devices are connected to the same channel and simultaneously transmitting?
• Have you checked if there are other APs using the same channel?

Try configuring the AP on a channel not used by any other in the vicinity, and only connect that Windows laptop with the Intel wNIC and drivers updated to the latest one.