TERMINAL APPARATUS AND RESPONSE SIGNAL MAPPING METHOD

摘要

PROBLEM TO BE SOLVED: To reduce situation that uplink data is punctured by plural response signals in a communication system to which carrier aggregation is applied using plural downlink unit bands.SOLUTION: A radio reception section 201 receives a piece of downlink allocation control information which is transmitted via a downlink control channel in plural downlink unit bands and downlink data transmitted via a downlink data channel indicated by the downlink allocation control information. An ACK/NACK control section 212 generates a response signal which includes a first response signal corresponding to a first downlink unit band and a second response signal corresponding to a second downlink unit band based on reception success/failure of the downlink data in plural downlink unit bands. An encoding section 213 encodes the first response signal and the second response signal. A symbol number of the first response signal and a symbol number of the second response signal are determined independently.