公开(公告)号：US10476536B1

公开(公告)日：2019-11-12

申请号：US16295794

申请日：2019-03-07

申请人： FUJITSU LIMITED

发明人： Toshio Kawasaki

IPC分类号： H04B1/62 ,  H04B1/04

摘要： A distortion compensation device includes an electric power amplifier that amplifies a transmission signal, and a processor that executes a process including: first identifying, by using a series that includes a plurality of coefficients or by using a look-up table that stores therein distortion compensation coefficients, an inverse characteristic of nonlinear distortion generated in the transmission signal in the electric power amplifier; second identifying, by using a plurality of coefficients, an inverse characteristic of linear distortion generated in the transmission signal in the electric power amplifier; and setting the coefficients for the first identifying and the second identifying such that a coefficient of a term with a degree of 1 in the series used in the first identifying or a sum of the plurality of coefficients used in the second identifying is a constant.

公开(公告)号：US10128800B2

公开(公告)日：2018-11-13

申请号：US15802151

申请日：2017-11-02

申请人： FUJITSU LIMITED

发明人： Tomoya Ota ,  Toshio Kawasaki

IPC分类号： H03F1/32 ,  H03F3/24 ,  H04B1/04

摘要： A distortion compensation apparatus include: a feedback unit that generates a feedback signal containing a first frequency component in which a plurality of odd-order distortions are superimposed and a second frequency component in which a plurality of even-order distortions are superimposed according to output of a power amplifier which amplifies a transmission signal; and a signal processor that separates the first frequency component and the second frequency component from the generated feedback signal and performs signal processing.

公开(公告)号：US09231523B2

公开(公告)日：2016-01-05

申请号：US14220776

申请日：2014-03-20

申请人： FUJITSU LIMITED

发明人： Toshio Kawasaki

IPC分类号： H03C3/00 ,  H04L27/20 ,  H04L25/06 ,  H03C5/00 ,  H03C3/02

CPC分类号： H03C5/00 ,  H03C3/00 ,  H03C3/02 ,  H03C2200/0041 ,  H03C2200/0058 ,  H04L25/067 ,  H04L27/20 ,  H04L27/206

摘要： A modulating device including: a first convertor configured to generate a converted analog signal by analog conversion on a input digital signal, a modulator configured to generate a modulated signal by quadrature modulation, a phase shifter configured to generate a phase shift signal by phase rotation, a demodulator configured to generate a demodulated signal by quadrature demodulation, a second convertor to generate a converted digital signal by digital conversion, a calculating circuit configured to estimate a the first direct current offset based on the input digital signal and the converted digital signal, the first direct current offset being a noise of digital current component generated between the input digital signal inputted to the first convertor and the output signal inputted to the demodulator, and a correcting circuit configured to correct at least one among from the input digital signal to the output signal based on the first direct current offset.

摘要翻译： 一种调制装置，包括：第一转换器，被配置为通过对输入数字信号进行模拟转换来生成转换的模拟信号;调制器，被配置为通过正交调制生成调制信号;移相器，被配置为通过相位旋转产生相移信号; 解调器，被配置为通过正交解调产生解调信号，第二转换器通过数字转换产生转换的数字信号;计算电路，被配置为基于所输入的数字信号和转换的数字信号来估计第一直流偏移， 第一直流偏移是在输入到第一转换器的输入数字信号与输入到解调器的输出信号之间产生的数字电流分量的噪声，以及校正电路，被配置为校正输入数字信号与输出之间的至少一个 信号基于第一直流偏移。

公开(公告)号：US10797737B2

公开(公告)日：2020-10-06

申请号：US16285009

申请日：2019-02-25

申请人： FUJITSU LIMITED

发明人： Tomoya Ota ,  Toshio Kawasaki

IPC分类号： H04B1/04

摘要： A distortion compensation device includes a generating unit, a calculation unit, a conversion unit, and a distortion compensation unit. The generating unit generates, from an output signal of a power amplifying unit that amplifies transmission signals having a plurality of different bands, a superimposed signal in which the transmission signals having the different bands have been superimposed. The calculation unit calculates, based on the superimposed signal, a coefficient indicating a forward characteristic of nonlinear distortion of the power amplifying unit associated with each of the transmission signals having the different bands. The conversion unit converts the coefficient calculated by the first calculation unit to a coefficient indicating an inverse characteristic of the nonlinear distortion of the power amplifying unit. The distortion compensation unit performs, by using the coefficients converted by the first conversion unit, a predistortion process on each of the transmission signals having different bands.

公开(公告)号：US10469179B2

公开(公告)日：2019-11-05

申请号：US15905313

申请日：2018-02-26

申请人： FUJITSU LIMITED

发明人： Tomoya Ota ,  Toshio Kawasaki

IPC分类号： H04B15/00

摘要： A distortion compensation apparatus includes: a generation unit that generates a first signal to be used on a transmission side and a feedback side in common; a conversion unit that converts a frequency of a third signal that is to be an even-order distortion compensation signal by using a second signal that is based on the first signal; and a compensation unit that compensates an even-order distortion in a transmission signal caused by amplification by using a signal obtained by frequency conversion for the third signal by the conversion unit.

公开(公告)号：US09300256B2

公开(公告)日：2016-03-29

申请号：US13874845

申请日：2013-05-01

申请人： FUJITSU LIMITED

发明人： Toshio Kawasaki

IPC分类号： H03F1/26 ,  H03F1/42 ,  H03F1/02 ,  H03F1/32 ,  H03F3/24

CPC分类号： H03F1/42 ,  H03F1/0294 ,  H03F1/3247 ,  H03F3/24

摘要： An amplification device includes a first filter configured to pass a predetermined frequency component of a first digital signal phase-modulated with a constant amplitude; a first distortion compensator configured to compensate the signal output from the first filter in advance for distortion occurring in an amplified signal, based on a first distortion compensation coefficient dependent on an amplitude of the signal output from the first filter; a first converter configured to convert the signal compensated by the first distortion compensator into a first analog signal; and a first amplifier configured to amplify the first analog signal.

摘要翻译： 放大装置包括：第一滤波器，被配置为传递以恒定幅度相位调制的第一数字信号的预定频率分量; 第一失真补偿器，被配置为基于取决于从第一滤波器输出的信号的幅度的第一失真补偿系数，预先补偿来自第一滤波器的信号从放大信号中发生的失真; 第一转换器，被配置为将由第一失真补偿器补偿的信号转换为第一模拟信号; 以及第一放大器，被配置为放大第一模拟信号。

公开(公告)号：US09237054B2

公开(公告)日：2016-01-12

申请号：US14165315

申请日：2014-01-27

申请人： FUJITSU LIMITED

发明人： Toshio Kawasaki

IPC分类号： H04L27/36 ,  H03F1/32

CPC分类号： H04L27/367 ,  H03F1/3247

摘要： A distortion compensation device includes: a memory configured to store a first and second table, different addresses being assigned to the first and second table respectively, each of the addresses being related to a distortion compensation coefficient to compensate for a non-linear distortion, a first address in the first table and a second address in the second table corresponding to respective first and second ranges of power or amplitude of a transmission signal, and parts of the first and second ranges overlapping each other; and a processor coupled to the memory and configured to: update the respective distortion compensation coefficients related to the first address and the second address simultaneously, in accordance with a single value of the power or the amplitude, and compensate for the non-linear distortion generated by an amplifier amplifying the power of the transmission signal, by using at least one of the first and second table.

摘要翻译： 失真补偿装置包括：被配置为存储第一和第二表的存储器，分别分配给第一和第二表的不同地址，每个地址与失真补偿系数相关以补偿非线性失真， 第一表中的第一地址和第二表中的第二地址对应于传输信号的功率或幅度的相应第一和第二范围，并且第一和第二范围的部分彼此重叠; 以及处理器，其耦合到所述存储器并且被配置为：根据所述功率或幅度的单个值，同时更新与所述第一地址和所述第二地址相关的各个失真补偿系数，并补偿所产生的非线性失真 通过使用第一和第二表中的至少一个来放大放大发送信号的功率的放大器。

公开(公告)号：US09088250B2

公开(公告)日：2015-07-21

申请号：US13927816

申请日：2013-06-26

申请人： FUJITSU LIMITED

发明人： Toshio Kawasaki

IPC分类号： H03F1/26 ,  H03F1/32 ,  H03F1/02 ,  H03F1/42 ,  H03F3/24

CPC分类号： H03F1/3252 ,  H03F1/0294 ,  H03F1/26 ,  H03F1/3247 ,  H03F1/42 ,  H03F3/24

摘要： A distortion compensating apparatus including: a processor to generate a compensated signal by performing distortion compensation on an input signal, based on a distortion compensation coefficient depending on the input signal, to separates the compensated signal into a first signal and a second signal that have constant amplitude and that have a phase difference based on amplitude of the compensated signal, to generate a third signal by multiplying the first signal by a first coefficient, and to generate a fourth signal by multiplying the second signal by a second coefficient, and a combiner to generate a seventh signal by combining the fifth signal and the sixth signal which are generated by amplifying the third signal and the fourth signal, wherein the processor is further configured to calculate the distortion compensation coefficient, the first coefficient, and the second coefficient, based on the third signal, the fourth signal and the seventh signal.

摘要翻译： 一种失真补偿装置，包括：处理器，用于通过根据输入信号对失真补偿系数进行输入信号的失真补偿来产生补偿信号，将补偿信号分离为第一信号和具有常数的第二信号 并且基于补偿信号的幅度具有相位差，通过将第一信号乘以第一系数来产生第三信号，并通过将第二信号乘以第二系数而产生第四信号，以及组合器 通过组合通过放大第三信号和第四信号产生的第五信号和第六信号来产生第七信号，其中处理器还被配置为基于以下方式计算失真补偿系数，第一系数和第二系数 第三信号，第四信号和第七信号。

公开(公告)号：US20190273541A1

公开(公告)日：2019-09-05

申请号：US16287767

申请日：2019-02-27

申请人： FUJITSU LIMITED

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

IPC分类号： H04B7/06 ,  H04B1/04

摘要： 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：US09813273B2

公开(公告)日：2017-11-07

申请号：US14862557

申请日：2015-09-23

申请人： FUJITSU LIMITED

发明人： Hiroyoshi Ishikawa ,  Toshio Kawasaki ,  Hikaru Ishikawa ,  Kazuo Nagatani

IPC分类号： H04L27/26 ,  H04L25/03 ,  H04L25/49

CPC分类号： H04L27/2624 ,  H04B2201/70706 ,  H04L25/03834

摘要： A peak suppression device includes an acquiring unit that acquires multiple envelopes of carrier signals that are included in a multicarrier signal, an adding unit that adds the envelopes to generate a combined envelope, a detecting unit that detects a peak value and a peak timing of the multicarrier signal by using the combined envelope, and a suppressing unit that suppresses a peak of the multicarrier signal in accordance with the peak value and the peak timing.