Abstract: A base station apparatus in a mobile communications system has a unit which transmits, to one or more user apparatuses, a downlink control signal including information for allocating a radio resource, a unit which receives an uplink signal from the one or more user apparatuses, and a unit which determines, based on a feedback from the user apparatus, a pre-encoding matrix indicator (PMI) indicating a pre-encoding matrix to be applied to multiple antennas of the base station apparatus. When a number of multiplexed users in the downlink control signal is no less than a predetermined number, the PMI indicating the pre-encoding matrix to be applied to a whole system bandwidth of the mobile communications system is reported to each of the user apparatuses.

Abstract: The present invention provides a reception apparatus and reception method that reduce the amount of operation processing, reduce the processing delay and allow high signal separation performance. The reception method of the present invention is characterized by receiving signals including a plurality of codewords transmitted by a plurality of streams and performing maximum likelihood detection-based signal separation in the same codeword in the received signals while performing continuous interference canceller-based signal separation between different codewords.

Abstract: To use CSI feedback information capable of sufficiently supporting MU-MIMO transmission and CoMP transmission in LTE-A systems, in a radio communication method of the invention, a radio base station apparatus (200) generates downlink transmission data including a report mode corresponding to a bandwidth to perform feedback of feedback information including channel quality information and spatial channel information, and an extension level of the feedback information, and multiplexes the downlink transmission data and a reference signal for feedback information to transmit to a mobile terminal apparatus (100), and the mobile terminal apparatus (100) receives a downlink signal including the report mode and the extension level, and generates feedback information associated with the report mode and the extension level to transmit to the radio base station apparatus (200).

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: To suppress deterioration of throughput characteristics in the entire system even when a plurality of transmission antennas is placed in an indoor environment, a base station apparatus (eNode B) is provided with a power control matrix generating section (508b) that generates a power control matrix (Sx) reflecting average reception power of each of transmission signals from a plurality of transmission antennas (TX#1 to TX#NTX), a codebook update section (508c) that updates a codebook which beforehand defines a plurality of precoding weights corresponding to the power control matrix (Sx), a precoding weight selecting section (508d) that selects precoding weights that maximize throughput or reception SINR obtained after combining the transmission signals from the updated codebook, and a precoding multiplying section (transmission power control section) (507) that controls transmission power of each of the transmission signals corresponding to the selected precoding weights.

Abstract: Provided is a downlink reference signal structure suitable for increase in number of transmission layers. A radio base station device (20) has a plurality of transmission antennas; a orthogonal RS sequence generator (22) for generating orthogonal reference signals based on a two-dimensional orthogonal code, the orthogonal reference signals being orthogonalized between downlink reference signals adjacent in two-dimensional directions of frequency direction and time direction to each other in one transmission layer and being orthogonalized in different transmission layers assigned to one radio resource; a multiplexer (23) for multiplexing transmission data and the orthogonal reference signals in the one transmission layer; and a transmitter for transmitting a transmission signal obtained by multiplexing the transmission data and the orthogonal reference signals, via the transmission antenna in transmission layers simultaneously.

Abstract: To suitably transmit feedback information for rank adaptation and precoding in uplink MIMO transmission to a user apparatus as feedback, a base station apparatus (200) is characterized by having a precoding weight/rank number selecting section (232) that determines rank information associated with the number of layers of spatial multiplexing in uplink, while determining a control amount of a transmission phase and/or transmission amplitude used in weighting for transmission antennas of a user apparatus, and transmission/reception sections (206a), (206b) that transmit the rank information determined in the precoding weight/rank number selecting section (232) to a mobile station (100) using an RRC signal, while transmitting the control amount to the mobile station (100) using a control channel signal.

Abstract: It is an object of the present invention to reduce a probability that MCSs including different modulation schemes may be selected and thereby improve a throughput characteristic of an entire system. The present invention includes a CQI information decoding section (101) that decodes a CQI of a downlink transmission stream and an MCS selection section (102) that includes a table (MCS table 1021) that defines a modulation/coding scheme (MCS) according to the CQI of the downlink transmission stream and defines modulation/coding scheme groups including the same modulation scheme and defined so that transmission rates are arranged in ascending order in each of the modulation/coding scheme groups, and selects an MCS of the downlink transmission stream based on the CQI of the downlink transmission stream decoded by the CQI information decoding section (101).

Abstract: An approach for resource allocation in a wireless communication network including a sender, a relay station and a receiver in case of a retransmission of information from the relay station to the receiver is described, wherein a resource necessary for retransmission is determined on the basis of the relayed channel and the relay function.

Abstract: To provide a radio base station apparatus and radio communication method capable of performing radio communications using downlink reference signal structures suitable for antenna virtualization, a radio base station apparatus (200) has a plurality of transmission antennas, generates CRSs used in demodulation of at least downlink control information, CQI-RSs generated for each of the transmission antennas used in measurement of channel quality, and DM-RSs generated for each stream used in demodulation of downlink transmission data, and multiplexes the CRSs, CQI-RSs and DM-RSs into a same transmission time unit to transmit from each of the antennas.

Abstract: Provided is a radio base station apparatus capable of selecting an optimal modulation and coding scheme for each transmission stream easily. The radio base station apparatus has a CQI information decoder (101) configured to decode CQIs of plural downlink transmission streams and an MCS selector (102) that has an N-dimensional table (two-dimensional reference table (1021)) in accordance with the number N of downlink transmission streams where combinations of modulation and coding scheme between the plural downlink transmission streams are defined in accordance with each of the CQIs of the downlink transmission streams and is configured to select from the combinations of modulation and coding scheme for the downlink transmission streams based on each of the CQIs of the downlink transmission streams decoded by the CQI information decoder (101).

Abstract: The present invention provides a method for transmitting MIMO related information. The method includes: encoding MIMO related information of a user equipment (UE) by a base station, and transmitting downlink control signaling including a result of the encoding; receiving by the UE the downlink control signaling transmitted by the base station, obtaining the result of the encoding, and obtaining the MIMO related information of the UE by decoding the result of the encoding. By adopting the method, the base station is enabled to transmit MIMO related information required by the UE to the UE with small signaling overhead.

Abstract: A communication apparatus to be used for a newer system employing an FDD scheme in an area where an older system and the newer system coexist. The communication apparatus includes a first communication unit communicating at least a downlink data channel of the newer system using a frequency band belonging to a first frequency range (3.4-3.8 GHz); and a second communication unit communicating at least an uplink control channel of the newer system using a frequency band belonging to a second frequency range (2 GHz band) lower than the first frequency range. The second frequency range is used for uplink and downlink communications in the older system.

Abstract: There is provided a mobile terminal apparatus and a radio base station apparatus capable of transmitting a downlink signal using an optimum feedback parameter even when a control delay exists and improving throughput characteristics of a downlink channel. A mobile terminal apparatus (1) measures a feedback parameter for a radio base station apparatus (3) using a received signal, obtains a feedback value, predicts a feedback parameter after a control delay in which the feedback value is reflected on transmission of a downlink shared channel to obtain a feedback predicted value, transmits the feedback predicted value to the radio base station apparatus, and the radio base station apparatus (3) selects a precoding weight of MIMO channel transmission using the feedback predicted value and schedules the downlink shared channel using the feedback predicted value.

Abstract: The present invention provides a base station apparatus capable of preventing degrading of throughput performance even when feedback information amount on precoding in uplink MIMO transmission is reduced. This base station (200) has a scheduler (231) for determining resource blocks used in wireless communications with each mobile station (100) adaptively, a precoding weight selecting section (232) for selecting a precoding weight for controlling phase and/or amplitude of a transmission signal for each antenna in the mobile station (100) based on reception quality on uplink at the resource blocks determined to the mobile station (100); and transmission/reception sections (206a and 206b) for transmitting the determined precoding weight to the mobile station (100).

Abstract: A base station apparatus includes multiple antennas including M physical antennas (#1, #3, #5, #7) of a first group and M physical antennas (#2, #4, #6, #8) of a second group; a reference signal multiplexing unit which multiplexes at least M types of reference signals (P#1-P#4) to resource blocks of a downlink signal; and a transmitting unit which wirelessly transmits the downlink signal. The M types of reference signals are multiplexed to a first resource block and a second resource block in the same arrangement pattern. The M types of reference signals (P#1-P#4) within the first resource block are transmitted from the physical antennas (#1, #3, #5, #7) of the first group. The M types of reference signals within the second resource block are transmitted from the physical antennas (#2, #4, #6, #8) of the second group.

Abstract: A user apparatus to which radio access schemes that are a single-carrier scheme and a multicarrier scheme are applied, includes: a radio access scheme setting unit configured to set a radio access scheme; a discrete Fourier transform unit configured to perform discrete Fourier transform on a modulated symbol sequence when the set radio access scheme is the single-carrier scheme; a serial parallel conversion unit configured to perform serial parallel conversion on a modulated symbol sequence when the set radio access scheme is the multicarrier scheme; a frequency domain signal generation unit configured to assign a radio resource to the modulated symbol sequence on which discrete Fourier transform has been performed or to the modulated symbol sequence on which serial parallel conversion has been performed to generate a frequency domain signal; a transmission signal generation unit configured to perform inverse fast Fourier transform on the frequency domain signal to generate a transmission signal; a transmissi

Abstract: The communication apparatus includes: a processing unit 52 configured to determine a data modulation scheme for each stream based on first signal quality q1 for each stream determined by the MMSE method; a processing unit 54 configured to determine second signal quality q2 corresponding to the first signal quality q1; a processing unit configured to determine third signal quality q3(1) of a stream by adding first signal quality q1(1) of the stream and a correction value ?q(1) derived from second signal quality q2(2) of equal to or more than 1 stream other than the stream; and a processing unit 58 configured to determine channel coding rate Rk corresponding to third signal quality q3(1) for each stream. The determined data modulation scheme and channel coding scheme are used for transmission of a following stream.

Abstract: A base station apparatus includes a transmit diversity setting unit configured to set a transmit diversity mode to be applied to a user equipment terminal; a reception quality calculating unit configured to determine reception quality corresponding to the transmit diversity mode based on the transmit diversity mode set by the transmit diversity setting unit; a scheduling unit configured to determine a user equipment terminal to which a radio resource is to be allocated based on the reception quality determined by the reception quality calculating unit; and a notifying unit configured to notify the user equipment terminal to which the radio resource is allocated as determined by the scheduling unit of the transmit diversity mode to be applied.

Abstract: A base station for communicating with a first user equipment terminal within a first system band and communicating with a second user equipment terminal within a second system band includes a first reference signal sequence generating unit configured to generate M types of reference signal sequences; a second reference signal sequence generating unit configured to generate N (N>M) types of reference signal sequences; a scheduling unit configured to allocate resource blocks to the first user equipment terminal and the second user equipment terminal; a signal multiplexing unit configured to multiplex the M types of reference signal sequences into the resource block for the first user equipment terminal and multiplex the N types of reference signal sequences into the resource block for the second user equipment terminal; and a transmitting unit configured to transmit signals including the M types of reference signal sequences and the N types of reference signal sequences.