| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a radio terminal and radio communication method capable of improving quality of radio communication by transmitting a SRS as a reference signal.SOLUTION: A radio base station allocates at least part in any downlink sub-frame as a first resource for receiving downlink user data, at least part of an uplink part in a switching sub-frame or part of an uplink sub-frame as a second resource for periodically transmitting a SRS, and at least part in any uplink sub-frame as a third resource for transmitting uplink user data including a DSR, to a radio terminal. The radio terminal transmits the uplink user data including the DSR by using the third resource reported from the radio base station, and receives a control message for reporting the second resource, which is transmitted using the first resource from the radio base station with an antenna having directivity formed depending on a state of a transmission path based on the DSR.</p> |
