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: A mobile communication method according to the present invention comprises: a step A of individually notifying, by a radio base station eNB, a mobile station UE performing CA of correspondence relation between a DL carrier for transmitting an “UL grant” and an UL carrier to which a PUSCH resource is assigned by the “UL grant”, and a step B of transmitting, by the mobile station UE, an uplink data signal using the PUSCH resource through the UL carrier based on the above-described correspondence relation when the “UL grant” is received through the DL carrier.

Abstract: The present invention is designed to reduce the influence of performance deterioration due to interference when CoMP transmission is adopted in a heterogeneous network. A user terminal measures the first reception quality in the first transmission period when a macro base station performs no transmission or reduces transmission power, and second reception quality in a second transmission period when the macro base station and low power nodes perform transmission, and transmits an uplink signal including the first reception quality and the second reception quality, to the macro base station, and the macro base station receives the uplink signal including the first reception quality and the second reception quality, and, when performing the coordinated multiple-point transmission, allocates radio resources for a user terminal that is located on an edge of a coordinated area in the first transmission period, based on the first reception quality and the second reception quality.

Abstract: The IRC receiver 10 according to the present invention includes a channel estimation unit 11 that performs a channel estimation process so as to estimate a channel matrix H, a transmission weight matrix generation unit 13 that generates a transmission weight matrix WTx, a covariance matrix estimation unit 12 that estimates an interference signal covariance matrix (I) including a covariance matrix RI+N and an interference signal component on the basis of CRS, an IRC reception weight generation unit 14 that generates an IRC reception weight WIRC on the basis of the channel matrix H, the transmission weight matrix WTx, and the covariance matrix RI+N, and a received SINR estimation unit 15 that estimates received SINR on the basis of the channel matrix H, the interference signal covariance matrix (I), the transmission weight matrix WTx, and the IRC reception weight WIRC.

Abstract: A user terminal reports a group radio quality of each of radio resource groups to a base station at a first frequence. The base station reports an allocated radio resource group to be allocated for radio communication with the user terminal to the user terminal. The user terminal reports unit radio qualities of radio resource units contained in the allocated radio resource group to the base station at a second frequence that is higher than the first frequence. The base station performs radio resource scheduling on the basis of the unit radio qualities.

Abstract: The present invention is designed to provide a radio base station apparatus, a mobile terminal apparatus, a radio communication system and a radio communication method which can cope with an increased number of users. A radio base station apparatus is provided with: a signal generating section that generates a first downlink control signal and a second downlink control signal for a mobile terminal apparatus; a first multiplexing section that multiplexes the first downlink control signal on a control region up to a predetermined number of symbols from the top of a subframe; a second multiplexing section that frequency-division-multiplexes the second downlink control signal on radio resources from the next symbol in the control region to the last symbol of the subframe; and a transmission section that transmits the first downlink control signal multiplexed on the control region and the second downlink control signal multiplexed on the radio resources.

Abstract: Appropriate reception processing is performed using a CRS-based estimation method for a covariance matrix RI+N. An IRC receiver 10 according to the present invention includes: a covariance matrix estimation unit 12/13 configured to estimate a covariance matrix RI+N based on a CRS; a missing element insertion unit 14 configured to insert a given value into an inestimable element in an interference-signal covariance matrix RI+N (“˜” is on R) of interference signal components contained in the estimated covariance matrix RI+N; an IRC reception weight generation unit 16 configured to generate an IRC reception weight WIRC by using the control signal and the covariance matrix RI+N having the given value inserted thereinto; and a signal separation unit 17 configured to separate the data signal from a received signal by using the generated reception weight and the control signal.

Abstract: A radio communication system includes multiple base stations including a first base station and a second base station, and a mobile station. A candidate base station selector selects multiple candidate base stations that are candidates for a radio access point for the mobile station on the basis of the reception powers reported by the mobile station. When the mobile station actually executes wireless communication with the base station, an access-point base station determiner determines, as an access-point base station that is the actual radio access point for the mobile station, a base station corresponding to a best reception quality among reception qualities measured in the protected resource and reception quality measured in the non-protected resource.

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: To provide a radio base station apparatus, a radio relay station apparatus and a resource allocation method each which perform resource division of a backhaul sub-frame more optimally and can improve a throughput of a system, in the case of relay transmission. The radio base station apparatus according to the present invention includes: a frequency bandwidth control section configured to control a frequency bandwidth in a backhaul sub-frame, based on the number of the backhaul sub-frames, the number of mobile terminal devices, and frequency utilization efficiency of a radio link; and a transmitting section configured to transmit the backhaul sub-frame with the frequency bandwidth controlled by the frequency bandwidth control section.

Abstract: A mobile station is classified into one of plural classes based on the reception quality from a base station. The allocations of resource blocks are executed at the base station so that a resource block used for the transmission of a data signal component for a mobile station in a class is not commonly used as a resource block for the transmission of a data signal component for another mobile station belonging to the same class but is commonly used as a resource block used for the transmission of a data signal component for a mobile station belonging to another class. A mobile station, based on the allocation of resource blocks, demodulates a data signal component corresponding to the mobile station after cancelling a data signal component corresponding to a low-quality mobile station.

Abstract: A base station apparatus having a control information generation section that generates, per fundamental frequency block, a downlink control information piece for demodulating a data channel that is transmitted for each of a plurality of fundamental frequency blocks assigned to a user terminal, a determining section that determines, per fundamental frequency block, a search space which is a candidate area where the downlink control information piece is arranged, and a transmission section that transmits a downlink control channel in which the search space containing the downlink control information piece is arranged is disclosed.

Abstract: The present invention is designed to use frequency resources effectively, even in the situation where a plurality of mobile terminal apparatuses of varying capabilities coexist. A communication system, in which a mobile terminal apparatus (10) and a base station apparatus (20) communicate using a basic carrier and an extended carrier that is additionally allocated to the basic carrier, in which: the base station apparatus has a setting section (310) that sets, in the extended carrier, a subframe of a first carrier type which can be received in each of a plurality of mobile terminal apparatuses of varying capabilities and a subframe of a second carrier type which can be received in part of the plurality of mobile terminal apparatuses, and a transmission section (203) that transmits the basic carrier and the extended carrier to the mobile terminal apparatus, and the mobile terminal apparatus has a receiving section (103) that receives the basic carrier and the extended carrier from the base station apparatus.

Abstract: Provided are a mobile terminal apparatus, a radio base station apparatus and a radio communication method, capable of saving PHICH resources enough and realizing effective retransmission control of uplink SU-MIMO. The radio communication method of the present invention is characterized in that a radio base station apparatus receives signals of plural codewords, when there is an error in each of the codewords, generates a one-bit negative response physical HARQ indicator channel signal and transmits the physical HARQ indicator channel signal, and a mobile terminal apparatus receives the physical HARQ indicator channel signal and transmits retransmission signals of all the codewords to the radio base station apparatus based on the negative response physical HARQ indicator channel signal.

Abstract: When time resource data that is assigned to a downlink control channel signal is reported on the downlink, the present invention improves the reliability of the time resource data that is reported, and prevent purposeless repetitions of retransmission requests. A base station apparatus (20) is provided herein, which jointly codes a carrier indicator of a basic frequency block with time resource data assigned to a downlink control channel signal corresponding to a downlink shared channel signal, generates a downlink control channel signal including the coded carrier indicator as the downlink control channel signal corresponding to the downlink shared channel signal, and transmits the generated downlink control channel signal by the basic frequency block assigned to the downlink control channel signal.

Abstract: A base station apparatus used in a mobile communication system to which an OFDM scheme is applied in downlink is provided with: a scheduler configured to perform assignment of radio resources to a user apparatus for each subframe; a control channel generation unit configured to generate a control channel for reporting a result of scheduling by the scheduler to the user apparatus; and a mapping unit configured to map the control channel and a data channel, wherein the control information includes information indicating a radio resource amount used for the control channel, and the mapping unit multiplexes information indicating the radio resource amount used for the control channel into a first OFDM symbol.

Abstract: To partially suppress interference to control channels of a pico-cell from a base station apparatus of a macro-cell and enable assignment of user data to a subframe besides the same subframe using a part of control channels with interference suppressed thereto, a base station apparatus disposed in a second system having a system band comprised of a plurality of component carriers for sharing at least a part of a frequency band with a first system having a macro-cell (C2) and covering a pico-cell (C1) is configured to generate a carrier indicator for indicating another component carrier to which user data is assigned besides the same component carrier on a control channel of the component carrier, while indicating another subframe to which user data is assigned besides the same subframe on the downlink control channel.

Abstract: A base station communicates with a user device transmitting an uplink signal based on a single-carrier transmission scheme. The base station includes a frequency hopping determining unit configured to determine whether to apply frequency hopping to the user device based on radio-wave propagation information from the user device and a traffic type of data to be transmitted by the user device; a scheduler configured to allocate frequencies to the user device based on uplink channel reception conditions of the user device; and a reporting unit configured to report allocation information indicating resource units allocated by the scheduler to the user device. When the frequency hopping determining unit determines to apply the frequency hopping to the user device, the scheduler allocates, to the user device, resource units with different frequency bands in different slots.

Abstract: To suppress deterioration of retransmission efficiency and retransmit a transmission signal efficiently, provided are a base station apparatus which divides, in a retransmission block dividing section, a transmission signal into retransmission blocks according to a retransmission block table with which are registered the numbers of the retransmission blocks, each of the transmission blocks is a retransmission unit of a transmission signal, the numbers of the retransmission blocks are required numbers corresponding to the number of transmission antennas and the system bandwidth in case that the maximum value of the size of the retransmission block is fixed to a certain value, and retransmits in downlink transmission signals associated with the divided retransmission blocks, and a mobile terminal apparatus which receives the transmission signals associated with the retransmission blocks from the base station apparatus, and combines the retransmission blocks to restore the transmission signal prior to division.

Abstract: A base station apparatus is used in a mobile communication system in which at least a shared data channel is transmitted by an orthogonal modulation scheme using an I-channel and a Q-channel. The base station apparatus includes a providing unit providing Acknowledgement/Non-Acknowledgement information indicating whether retransmission of a signal received in uplink is required; a mapping unit mapping a number of multiplexed users of the Acknowledgement/Non-Acknowledgement information to the I-channel or the Q-channel based on a predetermined mapping table; and a reporting unit reporting the Acknowledgement/Non-Acknowledgement information to the respective users. The mapping table indicates that, when the number of the multiplexed users is equal to or less than a predetermined number, the Acknowledgement/Non-Acknowledgement information is associated with the I-channel or the Q-channel, and otherwise, the Acknowledgement/Non-Acknowledgement information is associated with the I-channel and the Q-channel.