Patent ID: 8542625

Claim:
A method for ranging through ranging channels configured according to a frame structure in a radio communication system which supports a relay station (RS), the method comprising: configuring the ranging channels for a communication with the RS, the ranging channels including a first ranging channel located in an uplink subframe of a base station (BS) frame, a second ranging channel located in the uplink subframe of the BS frame, a third ranging channel located in an even-hop RS frame, and a fourth ranging channel located in an odd-hop RS frame; and performing ranging procedures between a BS and a mobile station (MS) and/or a subordinate RS through the configured ranging channels, wherein the third ranging channel has same position and size as the first ranging channel, and the fourth ranging channel has same position and size as the second ranging channel, when the RS is in a transparent relay mode, and wherein the third ranging channel has different position and size from the first ranging channel, and the fourth ranging channel has different position and size from the second ranging channel, when the RS is in a non-transparent relay mode.