Abstract: A transmission method selection section (223) selects either a first packet transmission method or a second packet transmission method. When the first packet transmission method is selected, an SRQ information generation section (224) generates SRQ (scheduling request) information based on the amount of data calculated by a data amount measuring section (221) and/or the retention time thereof, and the transmission power that can be used for packet data transmission calculated by a transmission power calculation section (222). On the other hand, when the second packet transmission method is selected, the SRQ information generation section (224) does not perform SRQ information generation, or generates SRQ information of a specific value for which packet data transmission is never permitted.

Abstract: Transmission destination determiner 301 selects communication terminals to be candidates to transmit a packet to from a packet transmission control signal, and determines a transmission destination apparatus based on CQI signals from the communication terminal apparatuses selected. Packet channel quality estimator estimates the quality of a received packet at the transmission destination apparatus based on the CQI signal, and, based on the estimation result, calculates a request packet quality for achieving a target packet quality upon retransmission based on the estimation result. Transmission power determiner 304, when receiving an ACK signal from the transmission destination apparatus, sets transmission power at a predetermined level, and, when receiving a NACK signal, determines transmission power to fulfill the request packet quality.

Abstract: In addition to dedicated channel signal formation units 101-1 to 101-N, control information channel signal formation unit 110 is provided and this control information channel signal formation unit 110 forms control information for carrying out uplink packet transmission. The control information channel signal formation unit 110 multiplexes control information (RG information, ACK/NACK, etc.) directed to a plurality of communication terminals through a channel encoding section 111 according to a multiplexing rule preset between the base station apparatus and each communication terminal and spreads the control information using a spreading code common to the communication terminals through a spreading section 113 and thereby forms a control information channel signal for uplink packet transmission.

Abstract: A base station apparatus and communication terminal apparatus capable of estimating interference with other cells on an uplink and realizing optimum assignment. At a base station (100), a scheduling and transmission parameter determining section (113) receives soft handover information from a higher layer and does not perform individual assignment processing for a mobile station in the process of soft handover. In this way, the mobile station can perform continuous transmission at a constant transmission rate (e.g., coding rate, modulation scheme, spreading factor, transmit power, etc.).

Abstract: Confidence calculator 211 finds confidence based on the measurement result of the received SIR. Based on the confidence supplied from confidence calculator 211, ACK/NACK decider 212 makes a decision for the then modulated ACK signal with reference to a predetermined threshold level. For the ACK/NACK decision result, scheduler 251 instructs buffer 252 to transmit new data when an ACK signal is received, and to transmit the data of the previous transmission when a NACK signal is received. By this means, it is possible to prevent loss of the received data in the communication terminal apparatus that occurs when a NACK signal is erroneously received and the data is not retransmitted from the associated communication terminal apparatus.

Abstract: Transmission destination determiner 301 selects individual communication terminal apparatus as candidates to transmit packets to and determines a transmission destination apparatus based on CQI signals from these communication terminal apparatuses. Transmission power determiner 302 monitors transmission power resources and determines the transmission power of an HS-PDSCH and the transmission power of a pilot channel. HS-PDSCH SIR estimator 303 estimates the SIR of the HS-PDSCH at the transmission destination apparatus based on the CQI signal and the transmission power. MCS determiner 304 determines the maximum TBS based on the HS-PDSCH SIR and indicates an MCS corresponding to the determined TBS to modulator 153. By this means, it is possible to maximize throughput in consideration of the transmission power of the HS-PDSCH.

Abstract: When an H-ARQ is used for downlink high-speed packet transmission, appropriate transmit power control is performed on a retransmission packet for effective use of transmit power resources and reduced interference in a radio communication system, and the transmit power of the retransmission packets (transmission #2, transmission #3) is controlled to transmit power value so that the reception quality of the retransmission packets at the mobile station apparatus is lower than the reception quality of the initial transmission packet (transmission #1) at the mobile station apparatus. For example, the transmit power value of the retransmission packet is controlled to a value lower than the transmit power value of the initial transmission packet by a predetermined value X [dB].

Abstract: Coherent detection correlation value calculation section 201 calculates correlation values for signatures in a received preamble. Non-coherent detection (j-segment) correlation value calculation section 202 calculates correlation values for the same signature by non-coherent detection. Maximum value detection section 203 detects a maximum correlation value from among the correlation values calculated by coherent detection and non-coherent detection. When the maximum correlation value is greater than a predetermined threshold, threshold determining section 104 recognizes, using the signature corresponding to this maximum correlation value, that the preamble generated and sent by a communication terminal apparatus corresponding to this signature has been received reliably.

Abstract: The interference component included in the power of a desired wave is eliminated by subtracting the product of a first correction factor determined from a multiplied by the interference power from the desired wave power so as to correct the bias error in the low SIR region The desired wave component included in the power of an interference wave is eliminated by subtracting the product of a second correction factor determined from the predetermined SIR characteristic diagram multiplied by the desired wave power from the interference power so as to correct the bias error in the light SIR region

Abstract: Delay profile generation sections 101 and 102 generate delay profiles from signals received from their respective antennas, delay profile addition section 104 adds up the delay profiles to generate an antenna combined delay profile. Path selection section 105 selects an arbitrary number of path phases from the delay profiles input through switching section 103 when a Doppler frequency is lower than a predetermined value and selects an arbitrary number of path phases of their respective antennas from the antenna combined delay profile when the Doppler frequency is higher than the predetermined value.