Patent ID: 8693354

Claim:
A method for generation of cyclic shift amount set, comprising the following steps: A: determining an upper limit value Ncs_max of cyclic shift amount Ncs according to a maximum cell radius value which is required to be supported by a random access channel RACH, and selecting Ncs values which are less than or equal to the Ncs_max to be elements of an initial Ncs set; B: calculating a root sequence number Nr corresponding to each element in the initial Ncs set according to formula Nr=┌M/└Npre/Ncs┘┐; and deleting elements in the initial Ncs set which have the same Nr value with other elements so as to generate a screening Ncs set in which each element has a different Nr value; C: if N, the number of elements in the screening Ncs set, is greater than P, the number of maximum Ncs supported by the system, then deleting N−P elements from the set so as to generate a final Ncs set; else regarding the screening Ncs set as the final Ncs set; D: at a base station, informing a mobile phone about an available step size of cyclic shift indicated by an element of the final Ncs set; wherein, M is a preamble number required by each cell; Npre is the length of preamble sequence.