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.

Abstract: A disclosed base station is used in a radio communication system where sounding reference signals from user terminals are multiplexed using distributed FDMA in which distributed frequency blocks each including frequency subcarriers discretely distributed in a system bandwidth are allocated to the user terminals, and the system bandwidth is repeatedly halved into frequency band segments according to a binary-tree structure.

Abstract: In a closed-loop TPC for a channel using a wireless resource, to which frequency hopping is applied, a high quality reception is achieved for all RBs without applying another technique to each RB. This transmission power control method, in a mobile communications system that transmits signals by frequency hopping in a plurality of resource blocks, includes a transmission power control method that transmission-power controls a channel in a closed loop using a wireless resource to which frequency hopping is applied, measures a reception channel quality of received signals for each resource block (RB1 and RB2), and transmits a TPC command-bit via a downlink so that the reception quality that is independently measured at each resource block among the resource blocks is made equal to a target reception quality.

Abstract: A disclosed OFDM-based transmission device includes a unicast channel generating unit configured to generate a unicast channel; an MBMS channel generating unit configured to generate an MBMS channel; a multiplexing unit configured to time-division-multiplex the unicast channel and the MBMS channel in the same frequency band; and a transmitting unit configured to transmit time-division-multiplexed transmission symbols. In the disclosed transmission device, the guard interval length for the MBMS channel is set longer than the guard interval length for the unicast channel.

Abstract: In a radio communication system defining a plurality of bandwidths, mobile terminals of kinds respectively corresponding to the plurality of bandwidths are accommodated in the system, and a minimum transmission bandwidth of the plurality of bandwidths is set as a transmission bandwidth of a downlink common channel. Or, every mobile terminal accommodated in the radio communication system is provided with a capability for processing a bandwidth equal to or greater than a predetermined value, and equal to or more than two transmission bandwidths that are equal to or less than a predetermined value are set as a transmission bandwidth of a downlink common channel. In the latter case, the mobile terminal identifies a bandwidth of a received downlink common channel.

Abstract: A base station includes a scheduler configured to perform frequency scheduling for each subframe; a control channel generating unit configured to generate a control channel including common control information to be mapped to radio resources distributed across a system frequency band and specific control information to be mapped to one or more resource blocks allocated to each selected user device; and a transmission signal generating unit configured to generate a transmission signal by time-division-multiplexing the common control information and the specific control information according to scheduling information from the scheduler. The common control information includes a format indicator representing one of preset options that indicates the number of symbols occupied by the common control information in one subframe. The common control information includes information units with a predetermined data size.

Abstract: A base station communicating with a user device using multiple antennas in a system where a subframe is composed of multiple slots each composed of multiple basic time units is disclosed. The base station includes a first mapping unit configured to map one or more reference signals used for demodulation of one or more L1/L2 control channels and one or more data channels to be transmitted from one or more of the antennas within a predetermined number of basic time units from the beginning of each subframe; and a second mapping unit configured to map reference signals used for demodulation of data channels to be transmitted from other ones of the antennas to one or more basic time units following the basic time units to which the reference signals used for demodulation of the L1/L2 control channels and the data channels are mapped.

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.

Abstract: To suppress deterioration of retransmission efficiency and retransmit a transmission signal efficiently even when the system bandwidth is extended, provided are a base station apparatus (20) which divides, in a retransmission block dividing section (21), a transmission signal into retransmission blocks according to a retransmission block table in which the number of the retransmission blocks each of which is a retransmission unit of a transmission signal is increased corresponding to the number of transmission antennas and registered, and retransmits in downlink transmission signals associated with the divided retransmission blocks, and a mobile terminal apparatus (10) which receives the transmission signals associated with the retransmission blocks from the base station apparatus (20), and combines the retransmission blocks to restore the transmission signal prior to division.

Abstract: A mobile station, a base station, a mobile communication system and a communication method enabling operations associated with simultaneous uplink reception in multiple stations to be simplified are provided. The base station includes a transmission timing determining unit determining a transmission timing based on scheduling conducted upon a data transmission request from a mobile station and notifying the mobile station of the transmission timing, and a receiving unit receiving data in accordance with the transmission timing.

Abstract: A base station apparatus includes a communication unit configured to communicate with base stations of a plurality of adjacent cells; a management unit configured to manage frequency bands for use in the adjacent cells; and a determination unit configured to determine instruction contents according to status of use of the frequency bands. The instruction contents are reported to all or a part of the adjacent cells via the communication unit. The instruction contents specify: a type of a pilot channel transmitted by a user residing in an adjacent cell; whether pilot channels of each user are code-division multiplexed or not; and whether pilot channels of each user are frequency-division multiplexed or not, and the like.

Abstract: A disclosed communication system includes multiple mobile stations and a base station. The mobile station maps a pilot channel comprising a CAZAC code to a signal including multiple frequency components arranged at regular intervals in a given frequency band, and transmits a transmission signal including the signal according to scheduling information. The mobile station performs the mapping such that its transmission signal and transmission signals of other mobile stations using different frequency bands become orthogonal to each other on a frequency axis. The base station calculates the correlation between a received signal and a pilot channel replica, performs channel estimation, and demodulates the received signal based on the result of channel estimation. The base station generates the pilot channel replica by mapping a pilot channel comprising a CAZAC code to a signal including multiple frequency components arranged at regular intervals in a given frequency band.

Abstract: The present invention is directed to a channel structuring method that includes a step of providing time frames segmented at a predetermined interval in communication channels of n subcarriers, a step of selecting a predetermined number of subcarriers from n subcarriers and a step of inserting a common control channel signal and a common pilot signal periodically into each of the time frames of the selected subcarriers.

Abstract: A mobile station configured to perform MIMO communication is disclosed, where the mobile station includes a control unit configured to determine a radio access scheme to be applied, based on at least one of a transmission frequency bandwidth to be used and a transmission stream number used in the MIMO communication.

Abstract: In a radio communication system defining a plurality of bandwidths, mobile terminals of kinds respectively corresponding to the plurality of bandwidths are accommodated in the system, and a minimum transmission bandwidth of the plurality of bandwidths is set as a transmission bandwidth of a downlink common channel. Or, every mobile terminal accommodated in the radio communication system is provided with a capability for processing a bandwidth equal to or greater than a predetermined value, and equal to or more than two transmission bandwidths that are equal to or less than a predetermined value are set as a transmission bandwidth of a downlink common channel. In the latter case, the mobile terminal identifies a bandwidth of a received downlink common channel.

Abstract: A user apparatus generates an uplink control channel including at least one of acknowledgement information and channel condition information on an downlink, and transmits the uplink control channel in a predefined dedicated band if no resource is assigned to transmit an uplink data channel. The uplink control channel includes multiple unit block sequences resulting from multiplication of the same factor with all chips of a CAZAC code sequence for the user apparatus.

Abstract: A transmitter comprises a first spreading unit configured to multiply each of multiple data symbols with a first spreading code sequence of a first spreading factor; a compression and repetition unit configured to compress output signals of the first spreading unit in time domain and repeat the compressed signal L times (where L is a natural number greater than or equal to 2); a phase modulation unit configured to multiply the compressed and repeated signal with a user dependent phase and output a data block consisting of L sub-blocks; a second spreading unit configured to replicate the data block according to a second spreading factor and multiply each set of the replicated sub-blocks with a second spreading code sequence of the second spreading factor to produce a two-dimensionally spread signal; and a wireless transmission unit configured to transmit the two-dimensionally spread signal using a single-carrier transmission scheme.

Abstract: A transmission apparatus for transmitting an uplink control signal by using a predetermined number of basic frequency blocks in a plurality of basic frequency blocks, wherein a system band is divided into a plurality of bands by a basic frequency block having a predetermined bandwidth, includes: a mapping unit configured to map control information to subcarriers in a basic frequency block in a given subframe; an inverse Fourier transform unit configured to perform inverse Fourier transform on a signal to which the control information is mapped; and a radio transmission unit configured to transmit a transmission signal, to a receiving apparatus by radio, including a signal on which inverse Fourier transform has been performed. In a subframe subsequent to the given subframe, the mapping unit maps the control information to subcarriers in a basic frequency block of a band different from a band of the basic frequency block in the given subframe.

Abstract: A user terminal apparatus that transmits to a base station apparatus a pilot channel at least in uplink by a single carrier method is provided with a mapping portion that maps transmission data to a long block of a sub-frame composed of plural short blocks and plural of the long blocks, and maps a pilot channel for demodulating a data channel and a pilot channel for measuring a CQI to the short blocks in accordance with a transmission band and a transmission method provided by notification from the base station.