Abstract: A base station includes a receiving unit configured to receive a UE capability regarding a bandwidth from a mobile station; and a specifying unit configured to specify, among plural basic frequency blocks included in a system band, one or more basic frequency blocks to be used by the mobile station based on the UE capability.

Abstract: A user apparatus in a multi input multi output (MIMO) mobile communications system using pre-encoding is disclosed. The user apparatus includes a PMI generator which generates, in accordance with a radio propagation condition, a pre-encoding matrix indicator (PMI) which indicates a pre-encoding matrix to be used by a base station; a delay circuit which takes, as an input, the PMI and which outputs the PMI after a predetermined delay period has elapsed; an accumulating unit which takes, as an input, the PMI from the delay circuit and stores the input PMI; and a channel estimator which, on a signal from the base station, performs channel estimation using the PMI stored in the accumulating unit.

Abstract: A base station for a mobile communication system includes a speed detecting unit configured to detect the moving speed of a user device based on a signal received from the user device and indicating the moving speed; and a determining unit configured to select, based on the moving speed detected by the speed detecting unit, a wideband channel quality indicator indicating reception quality of an entire system frequency band allocated to the mobile communication system, or a combination of the wideband channel quality indicator and one or more channel quality indicators of subbands in the system frequency band as channel quality information that needs to be reported from the user device to the base station.

Abstract: A user apparatus in a mobile communications system is disclosed. The user apparatus includes a unit which receives, from a base station apparatus, a downlink control signal including information for allocating a radio resource; a unit which determines, depending on a channel status, a pre-encoding matrix indicator (PMI) which indicates a pre-encoding matrix to be applied to multiple antennas of the base station apparatus; and a unit which transmits, to the base station apparatus, an uplink signal including the PMI, wherein, if the radio resource is allocated to a physical uplink shared channel of the user apparatus, the PMI is transmitted using a part of the radio resource, and, wherein, if the radio resource is not allocated to the physical uplink shared channel of the user apparatus, the PMI is transmitted in a physical uplink control channel which is allocated, in a fixed manner, to the user apparatus.

Abstract: A base station apparatus includes a correction unit for correcting a CQI reported from a user apparatus and a scheduler for scheduling based on the corrected CQI. The correction unit uses a correction table to correct the CQI such that if the reported CQI is poor, the CQI is slightly reduced, and otherwise, the CQI is significantly reduced. One method of generating the correction table includes deriving a first SINR in consideration of the number of interference users less than (n-1) and a second SINR in consideration of the number of interference users equal to (n-1) to explore a distribution of the second SINR to the first SINR. In this method, correspondence between the first SINR and the second SINR is determined based on the distribution to generate the correction table.

Abstract: A base station communicating using multiple antennas includes a direction-of-arrival (DOA) estimation unit configured to estimate a direction of arrival based on a signal from a mobile station and to output direction-of-arrival information regarding the estimated direction of arrival; a DOA information multiplexing unit configured to multiplex the direction-of-arrival information from the direction-of-arrival estimation unit with a shared data channel to be transmitted to the mobile station; and an antenna weight multiplying unit configured to multiply a signal to be transmitted to the mobile station and including the shared data channel multiplexed with the direction-of-arrival information by antenna weights obtained based on the direction-of-arrival information from the direction-of-arrival estimation unit.

Abstract: A transmitter includes multiple transmit antennas, a conversion unit configured to generate multiple signal sequences corresponding to a predefined frequency bandwidth from one or more transmission streams associated with any of the transmit antennas, a precoding unit configured to weight the signal sequences with a precoding matrix selected from a codebook including multiple predefined precoding matrices, and a transmitting unit configured to convert an output signal from the precoding unit into a number of signals corresponding to the number of transmit antennas and transmit the converted signals from the transmit antennas. The precoding unit applies distinct precoding matrices to different signal sequences, and an association between the distinct precoding matrices and the different signal sequences is determined through open-loop control being independent of a feedback from a receiver.

Abstract: A disclosed base station apparatus is capable of communicating with a user equipment terminal in a multi-input multi-output (MIMO) mobile communication system using Pre-coding. The base station apparatus includes a receiving unit receiving a Pre-coding Matrix Indicator (PMI) indicating a specific Pre-coding matrix, a determination unit determining a value of a flag indicator indicating whether the Pre-coding matrix specified in the PMI is to be used for downlink communications, a control signal generation unit generating a downlink control signal including at least the flag indicator, and a transmission unit transmitting a signal including the downlink control signal in downlink.

Abstract: A method of data processing includes the steps of: dividing user terminals into groups based on channel attributes and service requirements of the user terminals and setting a precoding code word and a cyclic delay for each of the groups; and determining which group a user terminal corresponding to the data to be processed belongs to and processing the data to be processed by the Cyclic Delay Diversity (CDD) precoding based on the precoding code word and the cyclic delay of the group. A data processing apparatus includes a grouping module and a CDD preceding module. By the method and apparatus above, the signal quality in the MIMO system can be improved.

Abstract: A wireless communication apparatus comprises an array antenna configured to receive a signal at multiple antenna elements; a DoA estimation unit configured to estimate directions of arrival of multiple paths contained in the received signal; an angle spread estimation unit configured to estimate an angle spread of the multiple paths; a first weighting calculation unit configured to estimate a common set of weighting factors for all the paths; a second weighting calculation unit configured to estimate an individual set of weighting factors for each of the multiple paths based on the estimated directions of arrival of the paths; a weighting unit configured to weight the received signal by multiplying the received signal by one of the common set of weighting factors or individual set of weighting factor; and a demodulator configured to demodulate the weighted signal.

Abstract: A wireless communication apparatus comprises an array antenna configured to receive a signal at multiple antenna elements; a DoA estimation unit configured to estimate directions of arrival of multiple paths contained in the received signal; an angle spread estimation unit configured to estimate an angle spread of the multiple paths; a first weighting calculation unit configured to estimate a common set of weighting factors for all the paths; a second weighting calculation unit configured to estimate an individual set of weighting factors for each of the multiple paths based on the estimated directions of arrival of the paths; a weighting unit configured to weight the received signal by multiplying the received signal by one of the common set of weighting factors or individual set of weighting factor; and a demodulator configured to demodulate the weighted signal.