Abstract: A base station device communicates with a mobile station device, either directly or via a relay station device. The base station device includes: a reference signal transmission instruction unit configured to instruct the mobile station device to transmit a reference signal; and a reference signal measurement instruction unit configured to instruct the relay station device to measure the reference signal that is transmitted by the mobile station device.

Abstract: A base station device includes: an information collection unit configured to collect information for calculating evaluation values for each of first, second, and third transmission paths; an evaluation value calculation unit configured to calculate the evaluation values for each of the first, second, and third transmission paths, based on the collected information; and a transmission path selection unit configured to select, using the evaluation values of each of the first, second, and third transmission paths, a transmission path to be used by a mobile communication terminal.

Abstract: A transmission channel selection method includes: collects information for calculating evaluation values of each of a plurality of transmission channels, and calculates separate evaluation values of the transmission channels individually with respect to each of a plurality of mobile stations; reduces the number of candidates for the transmission channels with respect to the plurality of mobile stations using the separate evaluation values; collects information for jointly calculating evaluation values of the transmission channels with respect to at least one of the plurality of mobile stations, and calculates the joint-separate evaluation values; and selects the communication paths of the plurality of mobile stations using the separate evaluation values and the joint-separate evaluation values.

Abstract: A base station device communicates with a mobile station device, either directly or via a relay station device. The base station device includes: a reference signal transmission instruction unit configured to instruct the mobile station device to transmit a reference signal; and a reference signal measurement instruction unit configured to instruct the relay station device to measure the reference signal that is transmitted by the mobile station device.

Abstract: A wireless communication system (1) includes a base station (200), one or a plurality of RNs (300) associated with the base station (200), and one or a plurality of mobile stations (100). When the mobile station (100) and the base station (200) communicate without going through the RN (300), the wireless communication system (1) uses a first transmission power control method to control the transmission power of the mobile station (100), and, when the mobile station (100) and the base station (200) communicate via the RN (300), the wireless communication system uses a second transmission power control method to control the transmission power of the mobile station.

Abstract: A wireless communication system includes a base station apparatus, a mobile station apparatus that performs wireless communication with the base station apparatus, and a relay station apparatus that relays wireless communication between the base station apparatus and the mobile station apparatus. The relay station apparatus switches between transmitting and not transmitting a synchronization signal or a reference signal to be transmitted to the mobile station apparatus.