Abstract: In a base station, wireless communication method, and wireless communication system, a base station belonging to a first communication system shares the same frequency band with a second wireless communication system. The bandwidth of the first system has at least 5 MHz and 1.4 MHz, a plurality of carriers is available for the 1.4 MHz and a single carrier is available for the 5 MHz in the first system, and a communication scheme of the first system uses a time division duplex long term evolution (TD-LTE). A communication scheme of the second system is different from the TD-LTE, and the base station enables a wireless communication using either 1.4 MHz bandwidth or 5 MHz bandwidth of the first system according to a status of use of the shared frequency band by the second system.

Abstract: A communication system having a plurality of base stations for carrying out radio communication by arranging a plurality of carriers each taking a first frequency bandwidth in a second frequency band that is predetermined and to be exceeded by the carriers arranged in succession, wherein the communication system arranges the carriers in the second frequency band in such a manner that each of the carriers has an overlapping portion overlapping with each other, and a first base station for using a carrier A, one of the carriers having the overlapping portion, preferentially uses, over a second base station for using a carrier B, a radio resource of a part of the overlapping portion in assigning user data.

Abstract: In a base station, wireless communication method, and wireless communication system, a base station belonging to a first communication system shares the same frequency band with a second wireless communication system. The bandwidth of the first system has at least 5 MHz and 1.4 MHz, a plurality of carriers is available for the 1.4 MHz and a single carrier is available for the 5 MHz in the first system, and a communication scheme of the first system uses a time division duplex long term evolution (TD-LTE). A communication scheme of the second system is different from the TD-LTE, and the base station enables a wireless communication using either 1.4 MHz bandwidth or 5 MHz bandwidth of the first system according to a status of use of the shared frequency band by the second system.

Abstract: Provided are a base station and a wireless communication method with which it is possible to avoid the effect of interference affecting another wireless communication system in a common band of wireless communication, and to provide high-speed communication service. The present invention has a configuration provided with a base station (30x) in which, when the other wireless communication system is not using the common band, a 3 MHz or 5 MHz carrier of the host system is used in which throughput is improved in comparison to a carrier having the frequency width of the other wireless communication system, and when the other wireless communication system is using the common band, a 1.4 MHz carrier of the host system is used having a smaller frequency width than the other wireless communication system.

Abstract: Provided are a base station and a wireless communication method with which it is possible to avoid the effect of interference affecting another wireless communication system in a common band of wireless communication, and to provide high-speed communication service. The present invention has a configuration provided with a base station (30x) in which, when the other wireless communication system is not using the common band, a 3 MHz or 5 MHz carrier of the host system is used in which throughput is improved in comparison to a carrier having the frequency width of the other wireless communication system, and when the other wireless communication system is using the common band, a 1.4 MHz carrier of the host system is used having a smaller frequency width than the other wireless communication system.

Abstract: Provided is a communication system that, in using a communication scheme such as TD-LTE, may attain a high speed communication by securing a bandwidth of carriers and prevent radio interference with another system by keeping the carriers within a frequency band assigned to the communication scheme. Specifically, the communication system having a plurality of communication apparatuses for carrying out a radio communication by assigning the plurality of communication apparatuses to a second frequency band with a predetermined bandwidth to be exceeded by carriers serially assigned, assigns the carriers to the second frequency band in such a manner as to overlap a portion of each of the carriers, and a communication apparatus (10a) using one of the carriers and a communication apparatus (10b) using the other carrier carry out the radio communication by preferentially using respective ranges of the overlapping portion.

Abstract: A communication system having a plurality of base stations for carrying out radio communication by arranging a plurality of carriers each taking a first frequency bandwidth in a second frequency band that is predetermined and to be exceeded by the carriers arranged in succession, wherein the communication system arranges the carriers in the second frequency band in such a manner that each of the carriers has an overlapping portion overlapping with each other, and a first base station for using a carrier A, one of the carriers having the overlapping portion, preferentially uses, over a second base station for using a carrier B, a radio resource of a part of the overlapping portion in assigning user data.

Abstract: Provided is a communication system that, in using a communication scheme such as TD-LTE, may attain a high speed communication by securing a bandwidth of carriers and prevent radio interference with another system by keeping the carriers within a frequency band assigned to the communication scheme. Specifically, the communication system having a plurality of communication apparatuses for carrying out a radio communication by assigning the plurality of communication apparatuses to a second frequency band with a predetermined bandwidth to be exceeded by carriers serially assigned, assigns the carriers to the second frequency band in such a manner as to overlap a portion of each of the carriers, and a communication apparatus (10a) using one of the carriers and a communication apparatus (10b) using the other carrier carry out the radio communication by preferentially using respective ranges of the overlapping portion.

Abstract: A radio apparatus, a transmission control method and a transmission control program are provided in which both of adaptive array processing and adaptive modulation are supported and a transmission directivity control scheme can be selected according to a modulation scheme.

Abstract: A radio apparatus, a transmission control method and a transmission control program are provided in which both of adaptive array processing and adaptive modulation are supported and a transmission directivity control scheme can be selected according to a modulation scheme.

Abstract: In an adaptive array (2000), fading rate of a user is measured by a fading rate measuring circuit (2300), and the transmit weight vector is weighted in accordance with the fading rate by a transmitting circuit (2400). Thus, transmission power is increased for a user of which fading rate is large, and thus transmission directivity control for such a user becomes possible.

Abstract: The control unit 50 calculates weighting factors for one symbol out of every k symbols. During this calculation, the control unit 50 calculates weighting factors for respective inphase and quadrature components of the symbol stored in every I and Q buffers based on the inphase and quadrature components. The control unit 50 also interpolates weighting factors for the remaining k-1 symbols. During this interpolation, the control unit 50 uses the weighting factors that are currently calculated and the weighting factors that have been previously calculated and are stored in the W buffer 51. The calculated and interpolated weighting factors are used for forming a directivity pattern.

Abstract: An adaptive array apparatus includes a control unit 50 and a plurality of radio units 10˜40 that each have a modulator 11, a transmission circuit 12, a switch 13, a phase detecting unit 14, a reception circuit 15, and a demodulator 16. For each radio unit 10˜40, the control unit 50 compensates a phase amount for generating a directivity pattern used for an output signal according to a difference in phase shift amounts between a transmission subsystem and a reception subsystem.

Abstract: An access control unit 3 includes a table showing how time slots are currently being assigned to mobile stations that are mid-communication. The access control unit 3 judges whether the reception signal level measured by the reception level detection unit 22 for each mobile station is at least equal to a threshold value. The access control unit 3 then changes the assignment and the table so that the mobile stations having a reception level that is at least equal to the threshold value occupy the same time slot. The access control unit 3 reduces the transmission power during this time slot to a level that is lower than the transmission power of other time slots. By doing so, interference with the transmission waves of nearby radio base stations can be avoided.

Abstract: A radio apparatus includes an antenna (104), and a transmission circuit (102) and a receiving circuit (105) sharing the antenna. The apparatus connects an output of the transmission circuit to an input of the receiving circuit in calibration for calculating the quantity of phase rotation and/or the quantity of amplitude fluctuation of a signal passing through the transmission and receiving circuits. Then, it connects a reference signal to the input of the receiving circuit for calculating the quantity of phase rotation and/or the quantity of amplitude fluctuation of a signal passing through the receiving circuit. Based on the subtraction of the information, the quantity of phase rotation and/or the quantity of amplitude fluctuation of a signal passing through the transmission circuit is calculated. It calculates a correction value for correcting difference in quantity of phase rotation and/or quantity of amplitude fluctuation between the transmission and receiving circuits on the basis of the information.

Abstract: A diversity receiving apparatus separately weights reception signals of a plurality of reception systems using combining coefficients based on a respective amplitude component of each reception signal and combines the weighted reception signals. The diversity receiving apparatus extracts symbol sections in the combined reception signals, and generates a clock for detecting symbols. The diversity receiving apparatus includes a converting unit 314 for uniformly multiplying the combining coefficients if every combining coefficient is below a predetermined threshold and I component ROMs, Q component ROMs, an I component adder 325 and a Q component adder 326 that combine the reception signals using the multiplied combining coefficients.

Abstract: An adaptive array radio base station comprises at least three antenna elements (ANTj (j=1, 2, . . . , n)) and a signal processing circuit (20). In calibration, the difference in a phase rotation quantity and the difference in an amplitude fluctuation quantity between a transmission circuit and a receiving circuit in each transmission system are estimated on the basis of a known signal transmitted from each transmission system and a received signal measured in each transmission system. A phase rotation quantity of a phase shifter (PSj) and an amplitude fluctuation quantity of an attenuator (ATTj) are set on the basis of the results of the estimation. Thus provided are a radio apparatus and a calibration method capable of calibrating transmission characteristics of the transmission circuit and the receiving circuit in a simple structure at a low cost without providing a specific measuring circuit.

Abstract: When signals for two mobile stations PS-A and PS-B are multiplexed using path division, a clock generating unit 52 generates a clock signal so as to delay the timing for transmitting symbols to the mobile station PS-B by 0.5 symbol periods relative to the transmission of symbols to the mobile station PS-A. If the transmission timing is adjusted in this way, a mobile station that picks up symbols which are spatially multiplexed with the signal for the present mobile station but are intended for another mobile station will not be synchronized with the symbols for the other mobile station.

Abstract: A wireless base station includes a determining unit, a first calculation unit and a control unit. The determining unit determines a direction in which a specified mobile station that is to be spatially-multiplexed is located. Then, the first calculating unit calculates a first parameter group, used to form a first directional pattern for each already connected mobile station that should be spatially-multiplexed with the specified mobile station. The first directional pattern is such that a null point is formed in the determined direction. After a link channel allocation has been transmitted to the specified mobile station, the control unit performs control, so that transmission is performed to each already connected mobile station by forming the corresponding first directional pattern and further by reducing transmission power uniformly in all directions.

Abstract: In an adaptive array (2000), fading rate of a user is measured by a fading rate measuring circuit (2300), and the transmit weight vector is weighted in accordance with the fading rate by a transmitting circuit (2400). Thus, transmission power is increased for a user of which fading rate is large, and thus transmission directivity control for such a user becomes possible.