An operation method of a terminal in a wireless communication system includes: transmitting uplink (UL) traffic information indicating a size of a UL data signal to a base station; receiving a jamming message generated based on the UL traffic information from the base station; generating an uplink (UL) transmission signal including the UL data signal and a UL jamming signal based on the jamming message; and transmitting the UL transmission signal to the base station. Also, the jamming message indicates a pattern of the UL jamming signal, the UL transmission signal is transmitted in a same frequency band as a frequency band in which a downlink (DL) transmission signal of the base station is received, and the UL jamming signal is transmitted in remaining resources excluding resources occupied by the UL data signal in the frequency band.