Patent ID: 8817720

Claim:
A method for determining a subband index, generating and storing an intermediate value table in advance according to possible values of M and N, the method further comprising: an Evolved Node B (eNB) receiving r, calculating a difference between the received r and a 〈 N - s i M - i 〉 corresponding to each obtained subband index, searching sequences 〈 N - 1 M - i 〉 , 〈 N - 2 M - i 〉 , … ⁢ , 〈 0 M - i 〉 , in the stored intermediate value table according to the calculated difference to obtain each s i , which constituting {s i } i=0 M−1 ; where i=0, 1, . . . , (M−1); N represents the number of subbands of a downlink system, M represents the number of subbands selected by a mobile terminal, r represents a combined index, and {s i } i=0 M−1 represents a set comprising M subband indexes sorted in ascending order.