Fujitsu Corporation

Hideyuki Kannari

Yusuke Tobisu

Tadahiro Sato

Yusuke Suzuki

Hiroyuki Sekino

Satoshi Matsubara

Masanori Hara

Manabu Shibata

Yoichi Endo

Hisato Kawano

Akihiko Komatsuzaki

Kohei Ohta

Kyosuke Mukaida

Hiroki Oikawa

A wireless communication device that implements beamforming includes: a storage, a processor, and a radio circuit. The storage stores directivity information that indicates a directivity of a radio intensity obtained when beams are formed in a plurality of main lobe directions designated in advance. The processor calculates, based on the directivity information, an interference to a first beam from a second beam when an instruction to form the first beam and the second beam is given. The first beam is configured to transmit a first signal in a first main lobe direction. The second beam is configured to transmit a second signal in a second main lobe direction. The processor generates, based on the calculated interference, a cancellation signal for canceling the second signal in the first main lobe direction. The radio circuit transmits the first signal and the cancellation signal.

Wireless communication device that implements beamforming

A wireless apparatus configured to be cascaded to another wireless apparatus through a transmission path and to be coupled to an antenna multiplexer, the another wireless apparatus being coupled to the antenna multiplexer, the wireless apparatus includes a processor configured to specify a first time length for a first transmission signal having a first frequency band to pass through the wireless apparatus, specify a second time length for a second transmission signal having a second frequency band to pass through the wireless apparatus, the transmission path, and the another wireless apparatus, specify a difference between the first time length and the second time length, delay the second transmission signal by the specified difference, generate a cancellation signal for an intermodulation distortion that occurs in a received signal due to intermodulation between the first transmission signal and the second transmission signal, and combine the cancellation signal with the received signal.

Wireless apparatus, method and non-transitory computer-readable storage medium

A wireless communication apparatus includes a generating unit, a detecting unit, and a suppressing unit. The generating unit generates, using signals at multiple carrier frequencies that are different from each other, a replica signal for passive inter modulation distortion that occurs in a reception signal from a terminal due to the transmission of a multicarrier signal that includes the signals at the multiple carrier frequencies. The detecting unit detects the correlation value between the replica signal for the passive inter modulation distortion and the reception signal. The suppressing unit suppresses the peak of the multicarrier signal when the correlation value is equal to or more than the threshold.

Wireless communication apparatus

A radio device includes: a processor that outputs a transmission signal containing a plurality of signals that are transmitted at different frequencies; an amplifier that amplifies the transmission signal output from the processor; and a transmitter/receiver that transmits by radio the transmission signal amplified by the amplifier and that receives by radio a signal having a frequency different from a frequency of the transmission signal. The processor generates a cancel signal based on the plurality of signals contained in the transmission signal, the cancel signal corresponding to an intermodulation distortion that occurs due to intermodulation among the plurality of signals, and the transmitter/receiver synthesizes the cancel signal generated by the processor with the transmission signal amplified by the amplifier.

Radio device and distortion cancelling method

A wireless device includes an input/output port that receives a first transmission signal subjected to transmission processing by another wireless device, the first transmission signal being output from the another wireless device, the another wireless device using a second frequency band adjacent to a first frequency band used by the wireless device, a synthesis circuit that synthesizes the first transmission signal received via the port and a second transmission signal subjected to transmission processing by the wireless device and that outputs the synthesized signal via an antenna, and a splitting circuit that splitbranches a first reception signal of the first frequency band and a second reception signal of the second frequency band, the first and the second reception signals being included in a reception signal received via the antenna, the splitting circuit outputting a split reception signal of the second frequency band via the port to the other wireless device.

Wireless device

A control device of a receiving device includes an interference wave detector that detects an interference wave within an intermediate frequency band in a signal converted by a mixer that converts a reception signal of a radio frequency band with a certain radio frequency as a center into an intermediate signal of the intermediate frequency band based on a signal of a local oscillation frequency different from the radio frequency. The control device further includes a frequency controller that changes the local oscillation frequency so that the intermediate frequency band gets away from a band of the interference wave when the interference wave is detected.

Control device, frequency control method, and receiving device

A base station includes antennas, a local signal generator; first and second mixers generating first and second mixed signals by mixing first and second signals from first and second antenna among the antennas and the local signal; first and second analog digital converters converting to first and second digital signals, first and second interference detecting units detecting first and second interference signals based on the first and second digital signals; first and second interference removing units generating first and second processed signals by removing the first and second interference signals by first and second filters having first and second filter central frequencies shifted in first and second directions from first and second interference central frequencies of the first and second interference signals, respectively; and a combining unit combining the first and second processed signals.

Base station and receiving method

In a wireless transmitting/receiving device of TDD system etc., a transmission signal is detected on the transmitting side in a specified transmission period, a signal reflected from an antenna through a circulator is detected on the receiving side in the transmission period and a reception signal is detected on the receiving side in a specified reception period. In this case, in a part of the transmission period a transmission signal having been detected on the transmitting side is selected while in the remaining part of the transmission period a reflection signal having been detected on the receiving side through a circulator from an antenna is selected, and in the reception period a reception signal having been detected on the receiving side through the circulator from the antenna is selected and outputted.

Wireless transmitting/receiving device

A diversity receiver respectively receiving signals in two branches includes two demodulating sections for producing respective amplitude and phases of received signals at a unit of symbol. The receiver includes a memory access section for producing an amplitude ratio of the amplitude of the received signals and a phase difference between the phases of the received signals. The receiver further includes a storage section for storing at least one relative phase difference between a phase of a vector-combined signal combined based on the received signals and one of the phases of the received signals for an address given by the amplitude ratio and the phase difference of the received signals. The phase of the vector-combined signal is previously calculated based on the amplitude ratio, the phase difference, and the one of the phases of the received signals. The receiver further includes an adding section for adding the relative phase difference produced from the storage section being addressed by the amplitude ratio and the phase difference produced from the memory access section to the one of the phases of the received signals to produce the phase of the vector-combined signal combined based on the received signals.

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Yokohama, Japan

Hideyuki Kannari