Abstract: A transmitter transmits data to a communicating opponent with a better channel condition with use of one or more frequency blocks including one or more carrier frequencies. The transmitter includes a communicating opponent selection unit evaluating the channel condition for each frequency block for each of plural communicating opponents and selecting one or more communicating opponents from the plurality of communicating opponents, a modulation scheme determination unit determining at least a modulation scheme depending on the evaluated channel condition, a control channel generation unit generating a control channel indicative of the determined modulation scheme and one or more frequency blocks available for the selected communicating opponents to receive a data channel, and a channel transmission unit providing the selected communicating opponents with the control channel and the data channel modulated in accordance with the modulation scheme.

Abstract: A base station apparatus is disclosed for use in a mobile communication system including multiple cells having multiple sectors. The base station apparatus includes a synchronization channel generation unit configured to generate a synchronization channel for use in cell search by a user apparatus and a transmitting unit configured to wirelessly transmit a signal including the synchronization channel. The synchronization channel includes a primary synchronization channel and a secondary synchronization channel. The primary synchronization channel includes multiple types of sequences, and the secondary synchronization channel transmitted in a sector of a cell includes a code derived from a predefined generation polynomial equation corresponding to the primary synchronization channel.

Abstract: A synchronization channel is generated by generating, as a P-SCH basic waveform, a signal sequence in which codes with constant amplitude in a frequency domain are placed at intervals of a predetermined number of subcarriers; transforming the signal sequence into a time domain; multiplying the signal sequence transformed into the time domain with a predetermined code sequence; retransforming the signal sequence multiplied with the predetermined code sequence into the frequency domain; generating an S-SCH signal sequence; and multiplexing the signal sequence retransformed into the frequency domain and the S-SCH signal sequence.

Abstract: In a radio communication system, a user terminal transmits a reservation packet to a base station using a common control channel (1), and the base station assigns an uplink data channel to the user terminal according to the reservation packet, and assigns a first shared control channel (2b) to the user terminal in association with the uplink data channel, and the mobile station transmits a control signal to the base station using the associated uplink shared control channel. According to status of radio communication, the base station may assign beforehand a second uplink shared control channel (2a) for which occupation by the user terminal is permitted only while the user terminal is performing communication.

Abstract: An apparatus for generating sets of radio parameters includes a first deriving unit deriving a set of radio parameters for specifying a symbol including an effective symbol part with the same period as the effective symbol part specified by another set of radio parameters and a guard interval part with a different period from the guard interval part specified by the other set of radio parameters. The apparatus further includes a second deriving unit deriving a set of radio parameters so that an occupancy proportion of the guard interval part in a single symbol specified by another set of radio parameters is equal to an occupancy proportion of the guard interval part in a single symbol specified by the other set of radio parameters.

Abstract: In a radio communication system, a user terminal transmits a reservation packet to a base station using a common control channel (1), and the base station assigns an uplink data channel to the user terminal according to the reservation packet, and assigns a first shared control channel (2b) to the user terminal in association with the uplink data channel, and the mobile station transmits a control signal to the base station using the associated uplink shared control channel. According to status of radio communication, the base station may assign beforehand a second uplink shared control channel (2a) for which occupation by the user terminal is permitted only while the user terminal is performing communication.

Abstract: There is disclosed a mobile station performing packet communications with a base station, including: a reservation control signal generating unit configured to generate a reservation control signal, based on control information transmitted in advance of a data packet; and a reservation control signal transmission control unit configured to transmit the reservation control signal at a predetermined timing.

Abstract: The present invention provides a radio base station apparatus and a mobile terminal apparatus compatible with respective mobile communication systems when a plurality of mobile communication systems coexist. The mobile terminal apparatus performs a cell search using a synchronization channel signal specific to a first mobile communication system made up of a plurality of component carriers multiplexed with at least one downlink component carrier in the first mobile communication system and/or a synchronization channel signal for a second mobile communication system having a relatively narrow second system band multiplexed with at least one downlink component carrier in the first mobile communication 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: 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: A mobile terminal apparatus and radio base station apparatus supporting each of a plurality of mobile communication systems when the plurality of mobile communication systems coexists is disclosed, wherein the mobile terminal apparatus is a mobile terminal apparatus in a radio communication system for performing transmission and reception in uplink and downlink, each assigned to a relatively wide system band obtained by aggregating a plurality of component carriers, each of which is a relatively narrow system band, and has coding and data modulation sections that perform coding and data modulation on uplink control signals including report information of individual component carriers assigned to downlink, and mapping sections that map the control signals subjected to coding and data modulation to uplink communication channels.

Abstract: A mobile terminal apparatus and radio base station apparatus supporting each of a plurality of mobile communication systems when the plurality of mobile communication systems coexists, where the mobile terminal apparatus performs a cell search using an SCH signal included in one downlink CC among a plurality of downlink CCs, and where the radio base station apparatus broadcasts a DBCH signal including information of an uplink CC paired with an initial downlink CC including the SCH signal obtained by the cell search, and transmits a response signal of an RACH signal from the mobile terminal apparatus to the mobile terminal apparatus in the initial downlink CC, and where the mobile terminal apparatus transmits a shared channel signal including information of a transmission/reception bandwidth of the mobile terminal apparatus to the radio base station apparatus in the uplink CC, and where the radio base station apparatus transmits a control signal including assignment information of a downlink CC and an uplink C

Abstract: An apparatus for generating sets of radio parameters includes a first deriving unit deriving a set of radio parameters for specifying a symbol including an effective symbol part with the same period as the effective symbol part specified by another set of radio parameters and a guard interval part with a different period from the guard interval part specified by the other set of radio parameters. The apparatus further includes a second deriving unit deriving a set of radio parameters so that an occupancy proportion of the guard interval part in a single symbol specified by another set of radio parameters is equal to an occupancy proportion of the guard interval part in a single symbol specified by the other set of radio parameters.

Abstract: A base station apparatus in a radio communications system is disclosed. The base station apparatus communicates with a mobile station using an OFDM scheme in downlink. The base station apparatus includes a sync signal generating unit which generates a secondary sync channel; a multiplying unit which multiplies a scramble code with the secondary sync channel; and a transmitting unit which transmits the secondary sync channel with which the scramble code is multiplied. Cell-specific information is detected by the secondary sync channel.

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: A mobile communication method is disclosed, where the mobile communication method includes the steps of determining, at a mobile station, a first cell with the largest interference amount among a plurality of cells in accordance with reception quality of a reference signal in the plurality of cells, when radio links are established between the mobile station and the plurality of cells, transmitting, from the mobile station to the plurality of cells, identification information of the first cell, and scheduling, at a radio base station which manages each of the plurality of cells, to transmit a data signal addressed to the mobile station via a resource that is unusable by the first cell.

Abstract: A mobile station, where the mobile station includes a reception quality measurement unit, a channel quality information transmission unit, and a control signal transmission unit, where the reception quality measurement unit is configured to measure a reception quality of a pilot signal of each of a plurality of cells, when a radio link is established with the plurality of cells, where the channel quality information transmission unit is configured to transmit, to a first cell having the beset reception quality among the plurality of cells, channel quality information corresponding to the reception quality, and where the control signal transmission unit is configured to transmit, to a cell other than the first cell among the plurality of cells, a control signal requesting not to transmit a data signal by using the same resource as the first cell.

Abstract: A transmission power control is disclosed, where the transmission power control includes transferring, from a second radio base station to a first radio base station, a second uplink signal received from a mobile station in a second cell, synthesizing, at the first radio base station, a first uplink signal received from the mobile station in a first cell with the second uplink signal transferred from the second radio base station, and generating and transmitting a transmission power control signal for controlling a transmission power of an uplink signal at the mobile station based on a reception quality of an uplink signal obtained by synthesizing the first uplink signal with the second uplink signal.

Abstract: A transmitter transmits data to a communicating opponent with a better channel condition with use of one or more frequency blocks including one or more carrier frequencies. The transmitter includes a communicating opponent selection unit evaluating the channel condition for each frequency block for each of plural communicating opponents and selecting one or more communicating opponents from the plurality of communicating opponents, a modulation scheme determination unit determining at least a modulation scheme depending on the evaluated channel condition, a control channel generation unit generating a control channel indicative of the determined modulation scheme and one or more frequency blocks available for the selected communicating opponents to receive a data channel, and a channel transmission unit providing the selected communicating opponents with the control channel and the data channel modulated in accordance with the modulation scheme.

Abstract: A mobile communications system includes a first system which communicates with a user apparatus in a frequency division duplex (FDD) scheme and a second system which communicates with a user apparatus in a scheme which is different from the first system. The second system conducts uplink and downlink communications within a frequency bandwidth between uplink and downlink of the first system. A geographical range of the second system is narrower than a geographical range of the first system. A downlink transmission power of a base station of the second system is weaker than a downlink transmission power of a base station of the first system.