Abstract: The present invention provides a mobile terminal apparatus, a base station apparatus, and a communication control method, which allow control suitable for interference reduction in a layered network such as HetNet, and which support a next-generation mobile communication system.

Abstract: A base station apparatus is used in a region in which a first system and a second system co-exist. In the first system, mobile communication is conducted using a variable system bandwidth not more than a basic bandwidth. In the second system, mobile communication is conducted using a variable system bandwidth which is not more than a bandwidth of an advanced system band which is at least as wide as multiple of the basic bandwidths. The base station apparatus generates a control signal for the first system and a control signal for the second system, orthogonally multiplexes them, and includes the same in a downlink signal to transmit the downlink signal. The advanced system band is divided such that it includes multiple of areas (P, Q, R, S) of the basic bandwidth. The control signal for the first system is included in one of the areas (Q). The control signal for the second system is included in at least one of the areas (P, Q, R, S).

Abstract: The present invention provides a base station apparatus, a mobile terminal apparatus and a communication control method which can improve the accuracy of channel quality estimation. A communication control method includes the steps of: allocating a CSI-RS (Channel State Information-Reference Signal), which is a reference signal for downlink channel estimation, in resources for the CSI-RS that are defined for CSI-RS transmission; setting to muting resources in the resources for the CSI-RS; and reporting parameters to specify the CSI-RS, including at least a transmitting subframe cycle, a subframe offset and transmission power, to a mobile terminal apparatus.

Abstract: A radio communication system includes a first radio base station that forms a first cell; a plurality of second radio base stations each of which forms a second cell; and a mobile station provided with a radio communication unit that connects, by radio, to each radio base station. The first radio base station specifies a correction value according to the number of the second cells formed in the first cell of the first radio base station and signals the correction value to the mobile station. The mobile station corrects a characteristic value indicating the reception characteristic of radio waves from the second radio base station by using the correction value. Either the first radio base station or the mobile station selects the destination of the mobile station according to the characteristic value of the first radio base station and the corrected characteristic value of the second radio base station.

Abstract: The present invention provides a base station apparatus, a mobile terminal apparatus and a communication control method which can improve the accuracy of channel quality estimation. A communication control method includes the steps of: arranging a CSI-RS, which is a reference signal for downlink channel estimation, in resources of subframes for CSI-RS transmission; setting, in the subframes for CSI-RS transmission, resources to which the CSI-RS is allocated in neighboring areas, to be muting resources; and reporting transmission interval information, which indicates a transmission interval of subframes that are set at the same timing in a transmission cycle of a subframe for CSI-RS transmission in a subject area and in a transmission cycle of a subframe for CSI-RS transmission in the neighboring areas, to a mobile terminal apparatus.

Abstract: A communications apparatus includes a receiving unit which receives a data channel for each predetermined transmission period; a determining unit which determines, for each data channel, acknowledgement information which indicates an acknowledgement or a non-acknowledgement; a generating unit which generates a control channel including the acknowledgement information; and a transmitting unit which transmits the control channel. For first and second data channels received during at least successive first and second transmission periods, the first and second acknowledgement information is provided. The second control channel which includes both the first and the second acknowledgement information which includes both the first and the second acknowledgement information is transmitted after a first control channel which includes the first acknowledgement information.

Abstract: A radio communication apparatus having a retransmission function includes a pattern storing unit configured to store a correspondence between resource blocks used for a transmission packet and resource blocks used for a retransmission packet; and a packet scheduling unit configured to arrange the retransmission packet based on the correspondence.

Abstract: With this transmission power control method, in a radio base station apparatus (10) of a macro cell, registration information as to whether or not a mobile terminal apparatus is a non-member mobile terminal apparatus, which is not a mobile terminal apparatus having registered access to a radio base station apparatus (20) of a femto cell, a received quality measurement result, and cell information, are received, whether or not a non-member mobile terminal apparatus has come near the femto cell is determined from the registration information, the received quality measurement result, and the cell information, and neighbor information, which indicates that a non-member mobile terminal apparatus has come near the femto cell, is reported to the radio base station apparatus (20) of the femto cell, by a backhaul link, and in the radio base station apparatus (20) of the femto cell, transmission power is reduced based on the neighbor information.

Abstract: It is an object of the present invention to provide a reference signal transmitting method, a mobile terminal apparatus and a base station apparatus capable of reducing influences on a PDCCH even when performing transmission control over an aperiodic reference signal for measuring channel quality.

Abstract: A disclosed base station in a multi-carrier system performs frequency scheduling in a frequency bandwidth including plural resource blocks each including one or more sub-carriers. The base station includes a frequency scheduler determining scheduling information for allocating one or more resource blocks to a communication terminal having good channel quality based on a channel quality indicator reported from plural of the communication terminals; a unit encoding and modulating a control channel transmitting the scheduling information; a multiplexing unit frequency-division multiplexing the control channel with a channel other than the control channel in accordance with the scheduling information; and a unit transmitting an output signal from the multiplexing unit in the multi-carrier system.

Abstract: A communication apparatus in a mobile communication system includes a first control information generation unit configured to generate first control information including retransmission information on a previously received data channel, a second control information generation unit configured to generate second control information including scheduling information on radio resources and a transmission signal generation unit configured to generate a transmission signal including a lower layer control channel including at least one of the first control information and the second control information. The transmission signal generation unit generates the transmission signal to transmit the first control information in any of subframes arriving at a first cycle and to transmit the second control information in any of subframes arriving at a second cycle longer than the first cycle.

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: A user apparatus transmits an uplink control signal to a base station apparatus using a single carrier scheme. The user apparatus includes: a unit configured to prepare acknowledgement information indicating positive acknowledgement or negative acknowledgement for a downlink data signal based on a result of demodulation of the downlink data signal; a unit configured to prepare channel state information indicating reception quality of a downlink reference signal; a unit configured to channel-code multiplexed control information in which the acknowledgement information and the channel state information are multiplexed to prepare the uplink control signal; and a unit configured to transmit the uplink control signal using dedicated resources different from resources for an uplink data signal.

Abstract: To provide a signaling method for enabling position information of muting resources to be signaled with a simplified configuration, base station apparatus and mobile terminal apparatus, the signaling method is characterized by having the steps of setting blank resources for a CSI-RS (Channel State Information-Reference Signal) that is a reference signal for downlink channel estimation, and transmitting a bitmap indicative of a position of the blank resources to a mobile terminal apparatus.

Abstract: Provided are a base station apparatus, a mobile terminal apparatus and a communication control method capable of preventing the increase in amount of signaling for uplink scheduling when allocation resource blocks are allocated in a discontiguous manner. The base station apparatus (20) determines discontiguous allocation positions of a first cluster and a second cluster to a frequency band. The frequency band is divided per RBG of a relatively small size (2 RBs) and the RBG is composed of contiguous RBs. The base station apparatus (20) indicates the allocation positions of the first cluster and the second cluster to a mobile terminal apparatus (10) with use of a group number of RBG of a relatively large RBG size (4 RBs).

Abstract: A base station includes a scheduler determining allocation of radio resources for each subframe; a control channel generating unit generating a control channel including common control information mapped across a system frequency band and specific control information mapped to one or more resource blocks allocated to a selected user device; and a transmission signal generating unit generating a transmission signal by time-division-multiplexing the common control information and the specific control information. The common control information is transmitted every subframe and includes information units with a predetermined data size, a format indicator representing one of preset options indicating the number of symbols occupied by the common control information, and information indicating the maximum number of the information units.

Abstract: To provide a mobile terminal apparatus and radio communication method for enabling feedback control information to be efficiently transmitted on a physical uplink control channel, a mobile terminal apparatus of the invention receives downlink shared data channels parallel in a plurality of CCs, makes determinations on the downlink shared data channels about ACK/NACK/DTX, collectively codes determination results (states) of the plurality of CCs after reducing the number of states allowed to be notified individually, and performs signal processing on the coded data to be orthogonalized between users to transmit.

Abstract: In each Mobile terminal, channel impulse characteristics from radio base stations to the mobile terminal is calculated. In a radio communication system, under the assumption that each of the mobile terminals performs optimum receiving beamforming in order to receive a data signal from a radio base station that actually sends the data signal to the mobile terminal, optimum receiving beamforming characteristics are estimated for each mobile terminal. Each of radio base stations that share optimum receiving beamforming characteristics calculates precoding characteristics for each mobile terminal according to the optimum receiving beamforming characteristics such that main beams are directed to mobile terminals to which the radio base station sends data signals and null beams are directed to mobile terminals to which the radio base station does not send data signals.

Abstract: To signal CSI-RS location indexes indicative of CSI-RS location positions in a resource block with high efficiency, a signaling method of CSI-RS is characterized by having the steps of locating a CSI-RS that is a reference signal for downlink channel estimation in resources for CSI-RS reserved to transmit the CSI-RS, generating a CSI-RS location index indicative of a location position of the CSI-RS located in the resources for CSI-RS, in the CSI-RS location index an index pattern varies corresponding to the number of CSI-RS ports so that an index pattern of the relatively low number of CSI-RS ports is a subset of an index pattern of the relatively high number of CSI-RS ports, and transmitting the generated CSI-RS location index to a mobile terminal apparatus.

Abstract: A base station includes: means configured to manage frequency blocks; means configured to determine, for each frequency block, scheduling information for assigning one or more resource blocks to a communication terminal being in a good channel state; means configured to generate a control channel including the scheduling information for each frequency block; and means configured to frequency multiplexing control channels within the system frequency band and to transmit it. In addition, the base station transmits the control channel by separating a non-specific control channel to be decoded by a non-specific communication terminal and a specific control channel to be decoded by a communication terminal to which one or more resource blocks are assigned.