Communication apparatuses and methods reduce the amount of signaling while maintaining a high scheduling gain. A determination unit stores a correspondence between the number of code words and the number of clusters to reduce the maximum value for the number of clusters allocated to each terminal as the number of code words increases, and thus determines the maximum value for the number of clusters based on the number of code words acquired. Based on the number of code words for a transmission signal from a terminal, an estimated value for the reception quality that is output by an estimation unit, and the maximum value for the number of clusters that is output by the determination unit, a scheduling unit schedules the allocation of the transmission signal transmitted by each terminal to a transmission band frequency (frequency resource) so as not to exceed the maximum value for the number of clusters.