Patent ID: 8145231

Claim:
A base station apparatus configurable to have a mobile station apparatus transmit a reference signal with a wide bandwidth without frequency hopping or with a narrow bandwidth with frequency hopping, the base station apparatus comprising: a setting unit configured to set a mapping of the reference signal; a transmitting unit configured to transmit, to the mobile station apparatus, control information related to the mapping of the reference signal; and a receiving unit configured to receive the reference signal, which is mapped to a frequency resource based on the control information and which is transmitted from the mobile station apparatus, wherein the wide bandwidth varies in a given system bandwidth, and said setting unit sets the mapping of the reference signal such that the reference signal is mapped to a frequency resource, which has the narrow bandwidth that is fixed regardless of variation of the wide bandwidth, and the frequency resource is uniformly dispersed in a frequency band of the wide bandwidth depending on the variation of the wide bandwidth.