Abstract: Disclosed are a method and apparatus for detecting minute oscillation in a WiBro repeater, and the WiBro repeater having the same. The method of detecting minute oscillation in a WiBro repeater includes: calculating an autocorrelation value of an input signal inputted to the repeater; calculating energy of the input signal; calculating the amount of oscillation by dividing the autocorrelation value by the energy; and comparing the amount of oscillation with a predetermined threshold value to determine whether or not the minute oscillation occurs in the repeater.

Abstract: A repeater including a downlink signal processor, which receives a downlink frame from a radio access station (RAS) and transmits the downlink frame to a portable Internet terminal, and an uplink signal processor, which receives an uplink frame from the portable Internet-terminal and transmits the uplink frame to the RAS, is provided, including: an ID storage unit to store identification (ID) information of the repeater; switches to switch a signal transmission path so that the downlink frame can be transmitted to the portable Internet terminal through the downlink signal processor, or the uplink frame can be transmitted to the RAS through the uplink signal processor; and a switch control unit to control the switches such that the ID information of the repeater is inserted into part of the downlink frame and the downlink and uplink frames are transmitted.