WiFi antenna understanding, which is 2.4, 5 GHz
The USB Wifi adapter you mentioned has two antennas. Each of these operates on both 2.4 and 5GHz bands per the specification-&quot;2.4G/5GHz Dual-Band 5dBi dipole antenna&quot;.
The reason you have 2 antennas is to enable the MIMO/beamforming/multiple concurrent transmissions capabilities as defined by 802.11ac