公开(公告)号：US11424774B2

公开(公告)日：2022-08-23

申请号：US17197295

申请日：2021-03-10

Applicant: FUJITSU LIMITED

Inventor： Tomoya Ota ,  Hiroyoshi Ishikawa ,  Alexander Nikolaevich Lozhkin ,  Toru Maniwa

IPC: H04B1/04 ,  H03F3/24 ,  H03F1/32 ,  H04L27/36

Abstract: A wireless communication apparatus includes: a processor that performs distortion compensation on a complex number transmission signal by using a distortion compensation coefficient; a power amplifier that amplifies the transmission signal subjected to distortion compensation by the processor; and a feedback path that feeds back a signal output from the power amplifier to supply a real number feedback signal to the processor. The processor executes a process including: estimating a complex number feedback signal by performing linear computation on the complex number transmission signal and the real number feedback signal; and updating the distortion compensation coefficient by using the estimated complex number feedback signal.

公开(公告)号：US20190273541A1

公开(公告)日：2019-09-05

申请号：US16287767

申请日：2019-02-27

Applicant: FUJITSU LIMITED

Inventor： Takenori Ohshima ,  Yoji Ohashi ,  Hiroyoshi Ishikawa ,  Atsushi Honda ,  Toru Maniwa ,  Alexander Nikolaevich Lozhkin ,  Toshio Kawasaki ,  Yuichi Utsunomiya ,  Tomoya Ota

IPC: H04B7/06 ,  H04B1/04

Abstract: A multiantenna communication device forms a directional beam by adding an antenna weight to respective signals of a plurality of antenna elements. The multiantenna communication device includes: a processor that executes performing distortion compensation on a transmission signal by using a distortion compensation coefficient; a plurality of power amplifiers that are provided corresponding to the antenna elements, and that amplify the transmission signal subjected to the distortion compensation by the processor; a multiplexer that multiplexes signals output from the power amplifiers to feed back; and an analog/digital (A/D) converter that A/D converts a multiplex feedback signal that is obtained by the multiplexer, wherein the processor executes updating the distortion compensation coefficient by using the multiplex feedback signal A/D converted by the A/D converter and the transmission signal.

公开(公告)号：US20220345162A1

公开(公告)日：2022-10-27

申请号：US17523950

申请日：2021-11-11

Applicant: FUJITSU LIMITED

Inventor： Alexander Nikolaevich LOZHKIN ,  Tomoya Ota

IPC: H04B1/04

Abstract: A wireless communication device includes: a plurality of power amplifiers provided for a plurality of respective antenna elements, each of the power amplifiers amplifying a signal; a distortion compensation unit that executes distortion compensation of a transmission signal by using an inverse function corresponding to nonlinear distortion generated in the power amplifiers; and a controller that operates by switching a first mode and a second mode, the first mode setting individual inverse functions for the respective power amplifiers in the distortion compensation unit and updating coefficients of the individual inverse functions, the second mode suspending the update of the coefficients of the individual inverse functions and setting, in the distortion compensation unit, an integrated inverse function acquired by performing weighted addition of the individual inverse functions.

公开(公告)号：US20220182105A1

公开(公告)日：2022-06-09

申请号：US17472739

申请日：2021-09-13

Applicant: FUJITSU LIMITED

Inventor： Tomoya Ota ,  HIROYOSHI ISHIKAWA ,  TORU MANIWA

IPC: H04B7/01 ,  H04B1/7107 ,  H04B7/0408 ,  H04B1/04

Abstract: A signal processing device includes: a first subarray that includes power amplifiers and phase shifters and that forms a first beam facing in a first direction; a second subarray that includes power amplifiers and phase shifters and that forms a second beam facing in a second direction; a feedback unit that feeds back at least signals that are output from the power amplifiers included in the first subarray; and a processor that is connected to the first subarray and the second subarray. The processor executes a process including: generating, based on a first feedback signal and a transmission signal output to the first subarray, a cancellation signal corresponding to an interference component applied to the second beam by the first beam; and adding the generated cancellation signal to a transmission signal output to the second subarray.

公开(公告)号：US10659124B2

公开(公告)日：2020-05-19

申请号：US16287767

申请日：2019-02-27

Applicant: FUJITSU LIMITED

Inventor： Takenori Ohshima ,  Yoji Ohashi ,  Hiroyoshi Ishikawa ,  Atsushi Honda ,  Toru Maniwa ,  Alexander Nikolaevich Lozhkin ,  Toshio Kawasaki ,  Yuichi Utsunomiya ,  Tomoya Ota

IPC: H04L27/00 ,  H04B7/06 ,  H04B1/04

Abstract: A multiantenna communication device forms a directional beam by adding an antenna weight to respective signals of a plurality of antenna elements. The multiantenna communication device includes: a processor that executes performing distortion compensation on a transmission signal by using a distortion compensation coefficient; a plurality of power amplifiers that are provided corresponding to the antenna elements, and that amplify the transmission signal subjected to the distortion compensation by the processor; a multiplexer that multiplexes signals output from the power amplifiers to feed back; and an analog/digital (A/D) converter that A/D converts a multiplex feedback signal that is obtained by the multiplexer, wherein the processor executes updating the distortion compensation coefficient by using the multiplex feedback signal A/D converted by the A/D converter and the transmission signal.

公开(公告)号：US09819370B2

公开(公告)日：2017-11-14

申请号：US14945801

申请日：2015-11-19

Applicant: FUJITSU LIMITED

Inventor： Hiroyoshi Ishikawa ,  Tomoya Ota ,  Kazuo Nagatani

IPC: H04B1/04

CPC classification number: H04B1/0475 ,  H03F1/3241 ,  H04B2001/0425

Abstract: A distortion compensation device includes: a storage configured to store a distortion compensation coefficient for compensating a distortion of a transmission signal to be amplified and transmitted, by corresponding to a combination of a plurality of addresses; a first generator configured to generate a first address according to a power or an amplitude of an input signal; a second generator configured to generate a second address according to a first vector to interconnect sample points on an IQ plane where the sample points of the input signal are drawn in time series; and a distortion compensation unit configured to acquire the distortion compensation coefficient corresponding to a combination of the first address and the second address from the storage, and to perform a predistortion processing on the input signal, by using the acquired distortion compensation coefficient, so as to generate the transmission signal.

公开(公告)号：US20160269058A1

公开(公告)日：2016-09-15

申请号：US15009041

申请日：2016-01-28

Applicant: FUJITSU LIMITED

Inventor： Tomoya Ota ,  Kazuo Nagatani

IPC: H04B1/04

CPC classification number: H04B1/0475 ,  H03F1/3241 ,  H03F3/24 ,  H04B2001/0408 ,  H04B2001/0425

Abstract: A distortion compensator that compensates for nonlinear distortion of an amplifier that amplifies power of a multicarrier signal includes a first compensation unit that performs first distortion compensation to collectively compensate for first nonlinear distortion that occurs in contact with a carrier frequency of the multicarrier signal, and second nonlinear distortion that occurs at a frequency at a predetermined distance from the carrier frequency, and a second compensation unit that performs second distortion compensation to compensate for only the first nonlinear distortion, of the first nonlinear distortion and the second nonlinear distortion.

Abstract translation: 用于补偿放大多载波信号功率的放大器的非线性失真的失真补偿器包括执行第一失真补偿以共同补偿与多载波信号的载波频率接触发生的第一非线性失真的第一补偿单元，第二补偿单元 在与载波频率预定距离处的频率处发生的非线性失真;以及第二补偿单元，其执行第二失真补偿以仅补偿第一非线性失真和第二非线性失真的第一非线性失真。

公开(公告)号：US20170180061A1

公开(公告)日：2017-06-22

申请号：US15351894

申请日：2016-11-15

Applicant: FUJITSU LIMITED

Inventor： HIROYOSHI ISHIKAWA ,  Tomoya Ota ,  Kazuo Nagatani

IPC: H04B15/00 ,  H04W52/52

CPC classification number: H04B15/00 ,  H04B1/0475 ,  H04B17/11 ,  H04B17/12 ,  H04B17/13 ,  H04B2001/0425 ,  H04W52/52

Abstract: A distortion compensation device includes a multiplier, a subtracter, an LUT, and a distortion compensation unit. The multiplier calculates the product of amplitudes or the product of power of transmission signals at two different times or calculates the ratio of amplitudes or the ratio of power of transmission signals at two different times. The subtracter calculates the phase difference between the transmission signals at two different times. The LUT specifies a distortion compensation coefficient by using both the product or the ratio calculated by the multiplier and the phase difference calculated by the subtracter. The distortion compensation unit performs, by using the distortion compensation coefficient specified by the LUT, a predistortion process on the transmission signal that is input to the amplifier.

公开(公告)号：US20170111064A1

公开(公告)日：2017-04-20

申请号：US15268081

申请日：2016-09-16

Applicant: FUJITSU LIMITED

Inventor： Tomoya Ota ,  Hiroyoshi Ishikawa ,  Kazuo Nagatani

IPC: H04B1/04

CPC classification number: H04B1/0475 ,  H04B1/0466 ,  H04B2001/0425

Abstract: A distortion compensation device includes an address generating unit, a look up table (LUT), and a multiplier. The address generating unit calculates pieces of difference information for different combinations each including transmission signals at different timings. Each of the pieces of difference information is the difference in amplitude or power between the transmission signals in a corresponding one of the combinations. The LUT specifies a distortion compensation coefficient by using the above pieces of difference information calculated by the address generating unit. The multiplier performs predistortion, using a distortion compensation coefficient specified by the LUT, on a transmission signal to be input to an amplifier.

公开(公告)号：US09584168B2

公开(公告)日：2017-02-28

申请号：US15009041

申请日：2016-01-28

Applicant: FUJITSU LIMITED

Inventor： Tomoya Ota ,  Kazuo Nagatani

IPC: H04B1/04

CPC classification number: H04B1/0475 ,  H03F1/3241 ,  H03F3/24 ,  H04B2001/0408 ,  H04B2001/0425

Abstract: A distortion compensator that compensates for nonlinear distortion of an amplifier that amplifies power of a multicarrier signal includes a first compensation unit that performs first distortion compensation to collectively compensate for first nonlinear distortion that occurs in contact with a carrier frequency of the multicarrier signal, and second nonlinear distortion that occurs at a frequency at a predetermined distance from the carrier frequency, and a second compensation unit that performs second distortion compensation to compensate for only the first nonlinear distortion, of the first nonlinear distortion and the second nonlinear distortion.

Abstract translation: 用于补偿放大多载波信号功率的放大器的非线性失真的失真补偿器包括执行第一失真补偿以共同补偿与多载波信号的载波频率接触发生的第一非线性失真的第一补偿单元，第二补偿单元 在与载波频率预定距离处的频率处发生的非线性失真;以及第二补偿单元，其执行第二失真补偿以仅补偿第一非线性失真和第二非线性失真的第一非线性失真。