RADIO BASE STATION APPARATUS, USER TERMINAL, WIRELESS COMMUNICATION SYSTEM, AND WIRELESS COMMUNICATION METHOD

摘要

The objective of the invention is to appropriately perform, in a structure wherein a downstream control channel has been extended, the allocation of downstream control signals for radio resources used for the extended control channel. There are included: an allocation unit for allocating downstream control signals to both a first control area extending from a front end of a frame that is a transmission time interval to a predetermined OFDM symbol and a plurality of second control areas that have been frequency-division-multiplexed with data areas in an area following the predetermined OFDM symbol and that have been structured in a predetermined resource block size, or only to the plurality of second control areas; and a transmission unit for transmitting the downstream control signals to user terminals. The allocation unit arranges that a plurality of extension control channel elements, each of which is a unit of allocation of downstream control information, be included in each of the plurality of second control areas. Further, the allocation unit divides the extension control channel elements and then performs a dispersion mapping in such a manner that the divided extension control channel elements are dispersed in each of the plurality of second control areas having different frequency bands.