The object of the invention is to prevent reduction of the system capacity caused by the use of a channelization code belonging to the secondary scrambling code. Instead of trying to select a channelization code belonging to each of the primary and secondary scrambling codes for one cell in a conventional manner, selection of a channelization code belonging to the primary scrambling code is tried sequentially for a plurality of cells (S02, S04). If the selection of the code has been failed, it is determined whether selection is tried again under a different condition (S06). Then, when trying again, selection of a channelization code belonging to the secondary scrambling code is tried sequentially for the plurality of cells (S07, S09).