RADIO BASE STATION, USER TERMINAL AND RADIO COMMUNICATION METHOD

摘要

PROBLEM TO BE SOLVED: To reduce communication overhead of a control signal in a communication system having a bandwidth of a physical downlink shared channel narrower than a system bandwidth.SOLUTION: A radio base station includes: a resource allocation unit for allocating for a user terminal a physical downlink shared channel to a predetermined narrow band out of a downlink system bandwidth; and a downlink control information generator unit for generating downlink control information to be reported to the user terminal. The downlink control information generator unit determines a region size related to resource allocation information included in the downlink control information related to the physical downlink shared channel, on the basis of the narrow band to which the physical downlink shared channel is allocated.