| 摘要 |
A mobile communication system according to embodiment comprises: a user terminal that performs D2D communication that is direct device to device communication; and a base station that performs cellular communication with the user terminal. The D2D communication is performed by using a part of uplink radio resources of the cellular communication. The base station transmits, to the user terminal, a timing advance value that is used for adjustment of a transmission timing in an uplink of the cellular communication. The timing advance value is commonly applied to the adjustment of the transmission timing in the uplink, and adjustment of a transmission timing in the D2D communication. |
