The configuration of a base station according to Embodiment 2 of the present invention is the same as the configuration shown in FIG. 7 of Embodiment 1 except for the function of RBG total number setting section 204. However, because RBG total number setting section 204 is the same as the above-mentioned RBG total number setting section 106 of a terminal in Embodiment 2, the detailed description thereon will be omitted.

As described above, while operating as Embodiment 1 when equation 9 is not valid, RBG total number setting section 106 matches notification RBG total number N_rb′ to allocation RBG total number N_rb as in the conventional technique when equation 9 holds true (as shown in FIG. 12, the number of signaling bits is one bit larger than the conventional technique). Thus, the number of signaling bits required for notification information r can be calculated by equation 3, and therefore it is possible to maintain the same number of signaling bits as the conventional technique.

When equation 9 is not valid, the frequency resources are allocated as shown in FIG. 8. Meanwhile, when equation 9 holds true, in the frequency resources allocation, the allocatable range is reduced by one RBG as shown in FIG. 13 to prevent an increase in the number of signaling bits.