Wireless communication method and wireless communication terminal using training signal

An operating method of a wireless communication terminal in uplink (UL) orthogonal frequency division multiple access (OFDMA) transmission, the method comprising:

• transmitting, to a base wireless communication terminal, a first one or more fields through a frequency band to a base wireless communication terminal, wherein a preamble of a physical frame includes the first one or more fields to be transmitted in a unit of 20 MHz through the frequency band and a second one or more fields to be transmitted through a sub-frequency band of the frequency band;
• adjusting a magnitude of a training signal corresponding to the sub-frequency band based on a number of subcarriers of the training signal corresponding to the sub-frequency band, wherein a plurality of training signals configured to be transmitted through an entire frequency band allocated for the UL OFDMA transmission include the training signal corresponding to the sub-frequency band and a training signal corresponding to a sub-frequency band which is not allocated to any wireless communication terminal;
• transmitting, to the base wireless communication terminal, the second one or more fields through the sub-frequency band, wherein the second one or more fields include a field including the training signal corresponding to the sub-frequency band and not including the training signal corresponding to the sub-frequency band which is not allocated to any wireless communication terminal;
• and
• transmitting, to the base wireless communication terminal, the data through the sub-frequency band allocated from the base wireless communication terminal, and
• wherein the training signal corresponding to the sub-frequency band is configured to be used, by the base wireless communication terminal, for automatic gain control for receiving the data from the wireless communication terminal,
• wherein the training signal corresponding to the sub-frequency band which is not allocated to any wireless communication terminal is not transmitted by any wireless communication terminal in the UL OFDMA transmission.