Mobile station device, radio communication method and circuit device

摘要

Disclosed is a mobile station device (1) that communicates with a base station device (3). The disclosed mobile station device (1) is provided with: a receiving unit (205) that receives both downlink data and a downlink control channel which contains information indicating a wireless resource for transmitting a contention-based signal; and a transmission unit (207). If a contention-based signal and an ACK/NACK in response to the downlink data collide in the same uplink time frame, the transmission unit transmits at least one of the ACK/NACK and the contention-based signal.