Sumitomo Electric Industries, Limited

Eiji Mochida

Takashi Yamamoto

Masahiko Onishi

Yoshizo Tanaka

Kenichi Murakami

Hirotsugu Yamamoto

Mitsuru Hirakawa

Hitoshi Hirata

Provided is a modeling device performing calculation using an amplifier model that models an amplifier of which an internal state affecting a distortion characteristic varies, wherein the amplifier model includes a plurality of calculation models that model the amplifier in different internal states, and a combiner that combines the plurality of calculation models at a combination ratio corresponding to the internal state that varies.

Modeling device, calculation method, and non-transitory computer-readable storage medium for distortion compensation of amplifer

A distortion compensation device includes: a first distortion compensation circuit having a first distortion compensation characteristic for compensating for a first distortion occurring in an output of an amplifier, the first distortion compensation circuit being configured to compensate for the first distortion; a second distortion compensation circuit having a second distortion compensation characteristic for compensating for a second distortion occurring in the output of the amplifier, the second distortion compensation circuit being configured to compensate for the second distortion; and an update unit configured to update the second distortion compensation characteristic. The first distortion includes a non-linear distortion and a memory effect distortion, the second distortion is a distortion whose temporal change is quicker than the first distortion, and the update unit updates the second distortion compensation characteristic at a higher frequency than an update frequency of the first distortion compensation characteristic.

Distortion compensation device, wireless communicator, predistorter, distortion compensation method, and computer program

Provided is a distortion compensation device performing distortion compensation on a signal to be amplified by an amplifier, of which an internal state affecting a distortion characteristic varies, using a distortion compensation model, wherein the distortion compensation model includes a plurality of calculation models having respective distortion compensation characteristic for the amplifier in different internal states, and a combiner combining the plurality of calculation models at a combination ratio corresponding to the internal state that varies.

Distortion compensation device, distortion compensation method, and non-transitory computer-readable storage medium

A distortion compensation device includes: a first predistorter configured to compensate for a distortion in an amplifier; and a second predistorter configured to compensate for the distortion in the amplifier, and update distortion compensation characteristics at a higher frequency than that of the first predistorter.

Distortion compensation device and distortion compensation method

A radio communication device includes: a baseband portion that generates a plurality of transmit signals destined for a same area; an antenna including a plurality of antenna elements; and a signal processing portion that splits each of the plurality of transmit signals generated by the baseband portion into signals for the respective plurality of antenna elements, multiplies each of the plurality of split transmit signals by a corresponding element of a weighting matrix, and then combines those of the transmit signals provided for each corresponding antenna element.

Radio communication device and method of determining weighting matrix

An amplifier deviceincludes: a distortion compensation sectionthat performs distortion compensation for an input signal x to an amplifierby digital signal processing; and a separation sectionthat separates an output signal from the amplifierinto an I signal as an analog signal component including phase information of the output signal and an analog signal component including power information of the output signal. The distortion compensation sectionperforms distortion compensation for the amplifier, based on 1-bit signals obtained by expressing, in 1 bit, the analog I signal and the analog signal component including the power information of the output signal, respectively.

Amplifier device and wireless communication device

A base station device is provided with a MAC unitwhich performs processing on a MAC layer for wireless communication, a schedulerwhich performs scheduling for determining allocation of radio resources, and a radio resource management unitwhich manages the radio resources. The scheduleris connected to the radio resource management unitso as to obtain information from the radio resource management unitwithout intervention of the MAC unit

Base station device and terminal device

There is provided a communication apparatus capable of effectively removing interference waves from a received signal while reducing the computation load. The communication apparatus includes a weight calculating unit. The weight calculating unit includes a calculating unit and a selecting unit. The calculating unit calculates a first weight and a second weight. The first weight is obtained, for a target known signal being an update target, by updating, using the target known signal, a weight of a first another known signal updated immediately before performing an update using the target known signal. The second weight is obtained, for a target known signal being an update target, by updating, using the target known signal, a weight of a second another known signal. The selecting unit selects one of the first weight and the second weight that has a lower estimation error.

Communication apparatus and base station apparatus

A communication system () includes a mobile communication network (); a fixed communication network () connected to the mobile communication network (); and a plurality of radio base stations capable of communicating with a mobile terminal () by radio communication. The radio base stations include a first base station () connected to the mobile communication network (); and second base stations () connected to the fixed communication network () through wire communication lines (). A communication connection using a predetermined interface is established between one of the second base stations () and one of neighboring base stations (the first base station () and another one of the second base stations ()) located in the neighborhood of the one of the second base stations ().

Communication system, compact base station, and communication method

A wireless communication apparatus including an MMSE combining processing unit that performs MMSE combining based on frequency domain received signals obtained by performing a discrete Fourier transform on received signals, the apparatus including an amount-of-phase-rotation estimating unit that estimates an amount of phase rotation occurring in the frequency domain received signals due to a shift in discrete Fourier transform timing of the received signals, and a reverse rotation unit that applies a reverse rotation of an amount of rotation corresponding to the amount of phase rotation estimated by the amount-of-phase-rotation estimating unit, to the frequency domain received signals, wherein the MMSE combining processing unit computes an MMSE weight based on the frequency domain received signals to which the reverse rotation has been applied by the reverse rotation unit, and performs MMSE combining.

Wireless communication apparatus with resource allocation to users performing array combining using array combining weights

When installing a femto base station device, failure that may occur in wireless communication is suppressed. The femto base station deviceincludes an RF unitwhich transmits broadcast information or paging information to a femto terminal devicecommunicating with the femto base station device, and an information storage unitwhich adds and stores, in the broadcast information or the paging information, location information that relates to the location of the femto base station deviceand is used by another wireless communication device to suppress interference.

Base station device, terminal device, receiver-side base station device, and wireless communication method

A decrease in weight calculation accuracy in MMSE combining caused by a shift in the discrete Fourier transform timing of received signals is prevented. A wireless communication apparatus BSincludes an MMSE combining processing unitthat performs MMSE combining based on frequency domain received signals obtained by performing a discrete Fourier transform on received signals. The wireless communication apparatus BSincludes an amount-of-phase-rotation estimating unitthat estimates an amount of phase rotation occurring in the frequency domain received signals due to a shift in discrete Fourier transform timing of the received signals; and reverse rotation unitsandthat apply a reverse rotation of an amount of rotation corresponding to the amount of phase rotation estimated by the amount-of-phase-rotation estimating unit, to the frequency domain received signals. The MMSE combining processing unitcomputes an MMSE weight based on the frequency domain received signals to which the reverse rotation has been applied by the reverse rotation unitsand, and performs MMSE combining.

Wireless communication apparatus using an estimate of the amount-of-phase rotation using pilot signals

A communication apparatus capable of simultaneously receiving signals from a plurality of users by an SC-FDMA scheme reduces its circuit size. A communication apparatus BS, BSis capable of simultaneously receiving signals from a plurality of users by the SC-FDMA scheme. The communication apparatus BS, BSincludes a plurality of antennasand; a processing unitthat performs multi-antenna signal processing on a plurality of received SC-FDMA signals in a frequency domain, the received SC-FDMA signals being received by the plurality of antennasand; and a user separating unitthat demultiplexes a signal obtained through the multi-antenna signal processing, into signals for each user based on user allocation information in the SC-FDMA scheme.

Communication apparatus for multi antenna signal processing

Interference suppression by beam forming is achieved even in an FDD (Frequency Division Duplex) system. A base station deviceperforms communication based on FDD. The base station deviceincludes a downlink signal reception unitthat receives a downlink signal transmitted from another base station device. The base station deviceperforms a beam forming process for directing a null beam to an arrival direction of the downlink signal from the another base station device, by using transmission path information between the base station device and the another base station device, the information being available from the downlink signal received by the downlink signal reception unit

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Osaka, Japan

Eiji Mochida