Patent ID: 8254247

Claim:
A method for transmitting signals by a base station in a wireless communication system, the method comprising: grouping data subcarriers of one or more Distributed Resource Units (DRUs) in an l-th Orthogonal Frequency Division Multiple Access (OFDMA) symbol into a plurality of subcarrier pairs; permutating the plurality of subcarrier pairs of the l-th OFDMA symbol; and transmitting signals through the plurality of permutated subcarrier pairs of the l-th OFDMA symbol, wherein the permutating is performed by using the following equation, q (PermSeq( ), s,m,l )={PermSeq({ f ( )+ s+l } mod { L DRU,FPi })+Downlink_PermBase} mod { L DRU,FPi } where PermSeq( ) denotes a permutation sequence of length L DRU,FPi , f( ) denotes a function having values [0, L SP,l −1] in accordance with at least m and s, L SP,l denotes a number of subcarrier pairs in the l-th OFDMA symbol within a Physical Resource Unit (PRU), m denotes a subcarrier pair index, s denotes a Distributed Logical Resource Unit (DLRU) index, l denotes an OFDMA symbol index, L DRU,FPi denotes a number of DRUs in an i th frequency partition (FP i ), Downlink_PermBase denotes 0 or a positive integer, and mod represents a modulo operation.