Patent ID: 9655142
Date: 2017-05-16
CPC Classifications: H04W

Claim:
1. A mobile station apparatus configured to communicate with a base station apparatus using a plurality of component carriers, the mobile station apparatus comprising: a reception unit configured to receive, on a PDCCH (physical downlink control channel), information used for initiating a random access procedure; and a transmission unit configured to transmit a random access preamble on a physical random access channel resource based on or in response to the information, wherein the reception unit is configured to receive a random access response corresponding to the random access preamble on one specific downlink component carrier among a plurality of downlink component carriers, the one specific downlink component carrier is linked to an uplink component carrier on which the random access preamble is transmitted on the physical random access channel resource, the information includes first information used for selecting the random access preamble, and the mobile station apparatus further comprises: a setting unit configured to set second information indicating a set of physical random access channel resources corresponding to the one specific downlink component carrier; and a selecting unit configured to, in a case that the first information is equal to zero,