I Bought a Wi-Fi NIC. The Vendor States It Is an 802.11a/b/g/n Network Card, But Why Did I Fail to Search 5 GHz AP Signals (AP Works on Channel 149) Using This NIC?
5 GHz AP signals are divided into three frequency bands: low frequency (5150 MHz to 5250 MHz), intermediate frequency (5250 MHz to 5350 MHz), and high frequency (5725 MHz to 5825 MHz). China supports low and intermediate frequency bands, but the Radio Association of China authorizes the 5.8 GHz frequency. Therefore, in China, the 5 GHz AP works on radio channels that use the 5.8 GHz frequency. These optional channels include channels 149, 153, 157, 161, and 165. Many types of NICs in the market support the 5.2 GHz frequency but not the 5.8 GHz frequency. To connect your NIC to 5 GHz AP signals, you can change the AP's working channels to the channels in low and intermediate frequency bands.