Abstract: A communication control method pertaining to an embodiment of the present invention is for controlling dual connectivity communication which uses a master base station that establishes RRC connection with a user terminal and a secondary base station that provides a supplementary wireless resource to the user terminal. The communication control method comprises: a step in which the master base station receives, from the user terminal, a measurement report which includes measurement results found for each cell in the user terminal; and a step in which the secondary base station receives, from the master base station, a supplementary request for requesting the allocation of resources to the user terminal. In the step for receiving a supplementary request, the master base station includes, in the supplementary request, measurement results for a cell of the secondary base station which is included in the measurement results, and transmits the same.

Abstract: A communication control method pertaining to an embodiment of the present invention is for controlling dual connectivity communication which uses a master base station that establishes RRC connection with a user terminal and a secondary base station that provides a supplementary wireless resource to the user terminal. The communication control method comprises: a step in which the master base station receives, from the user terminal, a measurement report which includes measurement results found for each cell in the user terminal; and a step in which the secondary base station receives, from the master base station, a supplementary request for requesting the allocation of resources to the user terminal. In the step for receiving a supplementary request, the master base station includes, in the supplementary request, measurement results for a cell of the secondary base station which is included in the measurement results, and transmits the same.

Abstract: A user terminal comprises: a receiver configured to: receive first information for a Device to Device (D2D) discovery procedure for discovering a proximity terminal, from a serving cell; and receive second information for the D2D discovery procedure from another cell of another frequency different from a frequency of the serving cell in order to receive a discovery signal by the D2D discovery procedure in the another frequency from another user terminal.

Abstract: A communication control method comprises: transmitting, by a communication apparatus, a Device to Device (D2D) resource notification to a user terminal. The D2D resource notification includes information indicating a predetermined D2D radio resource available in a D2D proximity service and information indicating a condition not allowing for use of the predetermined D2D radio resource.

Abstract: A communication method comprises: broadcasting, from a communication apparatus to a user terminal, system information for Device to Device (D2D) proximity service, by use of a frequency of a serving cell of the user terminal, the communication apparatus managing the serving cell. The system information includes first information and second information. The first information indicates an available frequency for a discovery procedure in which the user terminal discovers another user terminal. The second information indicates at least one parameter for calculating transmission power for the discovery procedure. The available frequency for the discovery procedure is a frequency different from the frequency of the serving cell. The first information is related to a center frequency of a frequency band of the available frequency for the discovery procedure.

Abstract: A communication control method comprises: receiving, by a user terminal, from a base station, first information indicating a Device to Device (D2D) frequency available in a D2D discovery procedure for discovering a proximal terminal; and using, by the user terminal, not only the frequency indicated by the first information, but also a frequency not indicated by the first information. The frequency not indicated by the first information is different from the frequency indicated by the first information and is indicated by second information received from another cell different from a cell in which the user terminal exists.

Abstract: A communication control method comprises: transmitting, by a user terminal to a base station, a message including information notifying the base station of the user terminal having an interest in receiving a discovery signal in a discovery procedure for discovering a proximal terminal, and information of a frequency in the discovery procedure, when the user terminal has an interest in the discovery procedure. The user terminal notifies the base station of a request for a gap for receiving the discovery signal.

Abstract: A mobile communication system supports cellular communication in which a data path passes through a core network and D2D communication that is direct device-to-device communication in which the data path does not pass through the core network. The system comprises a communication apparatus that assigns a radio resource to a D2D terminal that performs the D2D communication, wherein the communication apparatus performs assignment determination as to whether a dedicated radio resource not shared with the cellular communication is assigned to the D2D terminal or a shared radio resource shared with the cellular communication is assigned to the D2D terminal.

Abstract: A communication control method is a method for performing an offload from a cellular RAN to a wireless LAN. The communication control method includes the steps of: transmitting a list which contains identifiers of wireless LAN access points included in the wireless LAN, by a cellular base station included in the cellular RAN; receiving the list, by a user terminal which has a cellular communication unit and a wireless LAN communication unit; and performing an operation related to the offload after detecting that the user terminal approaches a wireless LAN access point on the basis of the list, by the user terminal which exists in a cell of the cellular base station.

Abstract: A communication control method for linking a cellular communication system with a wireless LAN system comprises: in a cellular base station, a step of storing location information of a wireless LAN access point; a step of acquiring location information of a user terminal connected to the cellular base station; a step of determining, on the basis of the respective location information of the wireless LAN access point and the user terminal, whether or not the user terminal is connected to the wireless LAN access point; and a step of transmitting a scan instruction for the wireless LAN access point to the user terminal when it is determined that the user terminal is connected to the wireless LAN access point.

Abstract: A mobile communication system performs downlink multi-antenna transmission by applying a precoder matrix that defines transmission directionality of downlink and a rank that defines number of signal sequences of the downlink. The mobile communication system comprises a user terminal that feeds back feedback information of a target frequency band, to a base station. The feedback information includes combinations of precoder matrix information indicating the precoder matrix and rank information indicating the rank.

Abstract: A non-anchor radio base station comprises: a non-anchor side measurement unit configured to measure reception quality of an uplink signal received from the radio terminal; and a notification unit configured to notify the anchor radio base station of the reception quality measured by the non-anchor side measurement unit. The anchor radio base station comprises: a transmission unit configured to transmit a control signal for adjusting a timing, at which the radio terminal transmits an uplink signal, to the radio terminal in order to adjust a timing, at which the uplink signal is received from the radio terminal, to a desired timing; and a determination unit configured to determine whether or not to exclude the non-anchor radio base station from the radio base station group on the basis of the reception quality notified from the non-anchor radio base station.

Abstract: A mobile communication system comprises: a base station, a first user terminal that establishes a connection with the base station, and a second user terminal that performs communication with the first user terminal via the base station, the mobile communication system supporting D2D communication that is direct device to device communication, wherein when it is determined that the D2D communication by the first user terminal and the second user terminal is possible, the base station transmits, to the first user terminal, an instruction for having a signal for discovery transmitted, the signal for discovery being used in discovery of a communication partner terminal in the D2D communication.

Abstract: A mobile communication system, which supports D2D communication that is direct device to device communication, comprises: a user terminal that transmits a discovery signal that is used for discovering a communication partner terminal in the D2D communication, wherein the user terminal transmits the discovery signal when the user terminal accepts start of communication and the user terminal has difficulty to establish a connection with a base station.

Abstract: In a radio communication system employing HARQ scheme wherein the maximum number of slots is changed, a radio terminal (1) which calculates a predictive transmission rate being the predictive value of a downlink transmission rate at a future time after the receiving time of a downlink radio signal is provided with a storage unit (15A) which stores in association with a DRC a corrected transmission rate obtained by causing a defined transmission rate being a downlink transmission rate in the case of using all the maximum number of slots to reflect the probability of succeeding in decoding data using only some of the slots, and a calculation unit (142) which predicts the reception quality at the future time on the basis of the reception quality before the receiving time, obtains from the storage unit (15A) the corrected transmission rate associated with the DRC corresponding to the predicted reception quality, and calculates the predictive transmission rate from the obtained corrected transmission rate.

Abstract: A wireless communication apparatus 100 according to the present invention is provided with reception channel coefficient calculation units 120-1 to 120-n for calculating reception channel coefficients of respective antennas, transmission channel coefficient calculation units 130-1 to 130-n for calculating transmission channel coefficients of respective antennas by extrapolation based on variations of the reception channel coefficients, absolute value calculation units 140-1 to 140-n for calculating absolute values of the transmission channel coefficients, a threshold calculation unit 150 for calculating a threshold based on the reception channel coefficients, comparison units 160-1 to 160-n for comparing the absolute values and the threshold, and transmission channel coefficient correction units 170-11 to 170-1n, when the absolute values are greater than the threshold, for correcting the transmission channel coefficients so as to match the absolute values to the threshold.

Abstract: A radio base station according to the present invention is equipped with a determination unit that compares a first signal quality of a first output signal which is output by an adaptive array antenna and a second signal quality of a second output signal which is output by an adaptive equalizer and determines whether the improvement effect of the second signal quality with respect to the first signal quality is below expectation. When the determination unit determines that the improvement effect is below expectation, a controller stops power supply to the adaptive equalizer and the calculation of an equalization weight by a weight calculator, and outputs the first output signal as the output signal of a receiver.

Abstract: A wireless communication method of a wireless communication apparatus (100) for performing wireless communication with a plurality of terminals based on the adaptive modulation scheme by using the space division multiple access scheme includes a data rate acquisition step of acquiring a data rate in a downlink to each terminal, a data rate estimation step of estimating a data rate in the downlink to each terminal based on the uplink signal quality of each terminal, a data rate difference calculation step of calculating, with respect to each terminal, a difference between the data rate estimated at the data rate estimation step and the data rate acquired at the data rate acquisition step and a channel assignment control step of controlling channel assignment to each terminal based on the difference in data rate calculated at the data rate difference calculation step.

Abstract: A channel prediction system (100) is provided with an estimation error calculator (130) which calculates an estimation error value representing the difference between a channel estimation value and a channel characteristic, and a prediction error calculator (140) for calculating a prediction error value indicating the difference between the channel prediction value calculated by a channel prediction unit (120) and a channel characteristic. The channel prediction unit (120) uses the channel prediction with priority over using the channel estimation value to calculate the channel prediction value corresponding to a future time when the estimation error value exceeds the prediction error value.

Abstract: An adaptive array wireless communication apparatus able to suitably select antenna elements, small in amount of processing, fast in convergence speed, and suitable for transmission/reception, and a method of the same, which controls the directionalities of array antenna elements based on array weights, controls an antenna element selecting unit 23 so that the antenna elements are intermittently determined, and adjusts a period of determination of the antenna elements based on information of the antenna elements determined at a controlling unit 26.