A wireless communication terminal operating as a Station (STA) is provided. The wireless communication terminal includes a wireless transceiver and a controller. The wireless transceiver performs wireless transmission and reception to and from an Access Point (AP). The controller receives a trigger frame including a Resource Unit (RU) Allocation subfield which has one bit to indicate support of 320 MHz bandwidth from the AP via the wireless transceiver, determines a combination of RUs to be used in a Trigger-Based Physical layer Protocol Data Unit (TB PPDU) according to the RU Allocation subfield, and sends the TB PPDU for Uplink (UL) data transmission to the AP via the wireless transceiver in response to the trigger frame.