Fujitsu Corporation

Shinichiro Kobayashi

Akihiko Komatsuzaki

Hideo Kato

Hiroyoshi Ishikawa

Satoshi Matsubara

Hideharu Shako

Kazuyuki Ozaki

Yoji Ohashi

Tadahiro Sato

Hiroshi Okagawa

Shunsuke Fujio

Ryo Koizumi

Yoshihisa Nakayama

Yusuke Furuumi

Katsuhiko Tsujihata

Kazunori Sato

Kunifumi Tamachi

Toshiyuki Takada

Yumihiko Annaka

Hiroshi Yasui

A radio communication apparatus includes a plurality of antennas, a radio transmission unit configured to execute radio transmission processing on data to be transmitted from the plurality of antennas, and a processor connected to the radio transmission unit. The processor executes a process including acquiring beam group specification information that specifies a beam group that is capable of being formed when the data to be transmitted is transmitted, forming at least one beam included in the beam group, and correcting an envelope of a beam group using correction factors, the beam group including the at least one beam formed, the correction factors corresponding to the beam group specification information.

Radio communication apparatus and radio transmission method

A peak suppression circuit includes a memory, and a processor coupled to the memory and the processor configured to suppress a first peak of a transmission signal according to a first sampling signal having a predetermined period, delay the transmission signal where the first peak is suppressed by a predetermined time corresponding to a period shorter than the predetermined period, and suppress a second peak of the delayed transmission signal according to a second sampling signal having the predetermined period.

Peak suppression circuit, peak suppression method, and transmitter

A radio communication apparatus configured to perform frequency conversion on a first transmission signal modulated at a frequency in a specific frequency band into a second transmission signal having a frequency in a transmission frequency band, in which the apparatus includes: a circuit configured to generate a first calibration signal having a frequency higher than a highest frequency in the specific frequency band, and a second calibration signal having a frequency lower than a lowest frequency of the specific frequency band; a circuit configured to add the first and second calibration signals to the first transmission signal; a circuit configured to estimate a phase at a center frequency in the specific frequency band of the first transmission signal, and output a phase correction coefficient corresponding to the estimated phase; and a circuit configured to correct the phase of the first transmission signal, based on the phase correction coefficient.

Radio communication apparatus and antenna calibration method

A radio apparatus includes an amplifier that amplifies electrical power of a signal that is wirelessly transmitted, and a processor that executes a process including: performing, by using a distortion compensation coefficient that compensates distortion generated in the amplifier, distortion compensation of an input signal; reading, from a predetermined memory, a threshold that varies in accordance with the electrical power of the input signal; and comparing the read threshold with a monitoring target which includes the distortion compensation coefficient used with respect to the input signal to monitor whether an abnormality is present in the distortion compensation of the input signal.

Radio apparatus and abnormality detecting method

A radio base station providing a service to a radio terminal by using plural component carriers includes a scheduler preferentially allocating, to the radio terminal, one of the component carriers that has a transmission power dynamic range whose lower limit value is lower than lower limit values of transmission power dynamic ranges of a rest of the component carriers; and a transmitter transmitting a radio signal to the radio terminal by using the allocated component carrier.

Radio base station, baseband processing apparatus, semiconductor integrated circuit, radio communication system and control method

A total of n signal processing circuits respectively constituted by independent circuit blocks process signals at the Data Link and Physical Layers. The signal processing circuits are associated with respective n groups of M/n subcarriers each, to process signals at the Data Link and Physical Layers. For example, the signal processing circuit independently processes signals of the subcarrier group at the Data Link and Physical Layers, the signal processing circuit independently processes signals of the subcarrier group at the Data Link and Physical Layers, and so on. The signal processing circuit independently processes signals of the subcarrier group at the Data Link and Physical Layers.

Wireless base station and signal processing method

A radio equipment controller includes a calculator that calculates a delay amount by subtracting from a given maximum delay amount an internal delay amount of a radio equipment and a delay amount of a cable, the radio equipment modulating and transmitting orthogonal frequency division multiplexing (OFDM) symbols, and the cable connecting the radio equipment and the radio equipment controller that creates the OFDM symbols, a detector that detects a beginning of the OFDM symbols from data that is inputted into a buffer that stores data of the OFDM symbols, and a delay controller that determines a transmission timing of the OFDM symbols so that the transmission timing of the beginning of the OFDM symbols becomes a timing that is delayed by the calculated delay amount after a reference signal with a specific period.

Radio equipment controller, radio control method, radio station, and radio communication system

Growing community of inventors

Yokohama, Japan

Shinichiro Kobayashi