公开(公告)号：US12057898B2

公开(公告)日：2024-08-06

申请号：US17797883

申请日：2020-03-02

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Hayato Fukuzono ,  Keita Kuriyama ,  Masafumi Yoshioka ,  Takafumi Hayashi

IPC: H04B7/04 ,  H04B7/0413 ,  H04L25/02 ,  H04L27/26

CPC classification number: H04B7/0413 ,  H04L25/0212 ,  H04L27/2607

Abstract: A transmission apparatus including the number of antennas different from a reception apparatus and performing transmission by SC-MIMO to and from the reception apparatus includes a training signal generation unit that generates a known signal predetermined, a CP addition unit that adds a CP to each symbol of a transmission signal including the known signal, a weight generation unit that generates a transmission weight based on a transposed adjugate matrix that is a product of a channel matrix estimated based on the known signal by the reception apparatus and a complex conjugate transpose of the channel matrix, and a transmission beam formation unit that uses the transmission weight to form a transmission beam for the transmission signal where the CP is added.

公开(公告)号：US12199710B2

公开(公告)日：2025-01-14

申请号：US17909206

申请日：2020-03-19

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Keita Kuriyama ,  Hayato Fukuzono ,  Masafumi Yoshioka ,  Takafumi Hayashi

IPC: H04B7/06 ,  H04B7/08

Abstract: A wireless communication method in a wireless communication system which includes a radio transmitting station apparatus having a plurality of antennas and a radio receiving station apparatus having an antenna and which performs transmission and reception of a radio signal with a single carrier. The wireless communication method includes: estimating a communication path matrix based on a training signal; transforming the estimated communication path matrix into a frequency domain, transforming a complex conjugate transposed matrix of each of a unitary matrix and an adjoint matrix obtained by performing singular value decomposition for each frequency with respect to the transformed frequency domain communication path matrix into a time domain, and adopting each as a reception weight matrix and a transmission weight matrix; performing transmission beam formation based on the transmission weight matrix; and performing reception beam formation based on the reception weight matrix.

公开(公告)号：US11870517B2

公开(公告)日：2024-01-09

申请号：US17602192

申请日：2020-03-26

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Keita Kuriyama ,  Hayato Fukuzono ,  Masafumi Yoshioka ,  Tsutomu Tatsuta

IPC: H04B7/0456 ,  H04B7/005 ,  H04B7/06 ,  H04B7/08

CPC classification number: H04B7/0456 ,  H04B7/005 ,  H04B7/06 ,  H04B7/08

Abstract: According to the present invention, in a wireless communication system that performs single carrier MIMO transmission between a transmitting station device and a receiving station device, the transmitting station device includes a time-domain linear equalization unit, a propagation path characteristics estimation unit configured to receive a training signal and estimate a transfer function matrix of propagation path characteristics, a filter tap calculation unit configured to calculate filter tap coefficients for the time-domain linear equalization unit based on the transfer function matrix by a predefined approach, and a transmission mode determination unit configured to make the filter tap calculation unit calculate the filter tap coefficients when the transfer function matrix meets a predefined condition, and to change a transmission mode and determine the transmission mode that meets the predefined condition when the transfer function matrix does not meet the predefined condition. The receiving station device includes a training signal generation unit configured to generate the training signal for use in estimation of propagation path characteristics and transmit the training signal to the transmitting station device.

公开(公告)号：US11838167B2

公开(公告)日：2023-12-05

申请号：US17596064

申请日：2020-05-28

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Hayato Fukuzono ,  Tomohiro Tokuyasu ,  Keita Kuriyama ,  Hiroyuki Furuya ,  Yu Ono ,  Tsutomu Tatsuta ,  Tomohiro Nakayama

IPC: H04L27/36 ,  H04W72/08 ,  H04W28/18 ,  H04W72/54

CPC classification number: H04L27/36 ,  H04W28/18 ,  H04W72/54

Abstract: Provided is a wireless communication system configured to accommodate a plurality of circuits to transmit a signal from a transmitter to a receiver, the system including a number-of-circuits observation unit configured to observe the number of circuits among the plurality of circuits through which communication is being performed; a quality observation unit configured to observe a quality of each of a plurality of communications; a determination unit configured to determine a modulation scheme for transmitting a signal based on the number of circuits observed by the number-of-circuits observation unit, the quality of each of the plurality of communications observed by the quality observation unit, and a required throughput of each of the plurality of circuits; and a modulation unit configured to modulate the signal using the modulation scheme determined by the determination unit.

公开(公告)号：US11677597B2

公开(公告)日：2023-06-13

申请号：US17595055

申请日：2019-05-21

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Hayato Fukuzono ,  Keita Kuriyama ,  Tomohiro Tokuyasu ,  Tsutomu Tatsuta

IPC: H04L27/01

CPC classification number: H04L27/01

Abstract: A wireless communication device includes an estimation observation unit that observes a channel condition by estimating a tendency of a long delay wave and a channel fluctuation from a received signal in which a training signal is added to a data frame, a first equalizer that compensates for the received signal, a second equalizer that compensates for the received signal with a property of having a higher long delay wave tolerance and a lower channel fluctuation tolerance than the first equalizer, and a control unit that performs control which switches such that the first equalizer or the second equalizer performs compensation for the received signal, on the basis of the channel condition observed by the estimation observation unit.

公开(公告)号：US11489557B2

公开(公告)日：2022-11-01

申请号：US17433443

申请日：2020-02-19

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Keita Kuriyama ,  Hayato Fukuzono ,  Tsutomu Tatsuta

IPC: H04B7/005 ,  H04B1/04 ,  H04B7/0417 ,  H04L27/01

Abstract: In the present invention, a transmitting station apparatus includes a training signal generation unit, a transmission end linear equalization unit configured to output a plurality of second data signals obtained by equalizing IAI of a plurality of first data signals by using a transmission end transfer function for equalizing IAI, and a transmitting station communication unit configured to transmit a training signal or the plurality of second data signals to a receiving station apparatus and receive information on the transmission end transfer function from the receiving station apparatus, and the receiving station apparatus includes a communication path estimation unit configured to estimate a communication path response from the training signal received by the receiving station communication unit, a reception end coefficient calculation unit configured to calculate the transmission end transfer function and a reception end transfer function for equalizing ISI, based on the communication path response, and a reception end linear equalization unit configured to output a plurality of third data signals obtained by equalizing ISI from the plurality of second data signals received by the receiving station communication unit by using the reception end transfer function.

公开(公告)号：US09872295B2

公开(公告)日：2018-01-16

申请号：US14892491

申请日：2014-05-23

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Hayato Fukuzono ,  Tomoki Murakami ,  Riichi Kudo ,  Shoko Shinohara ,  Yasushi Takatori ,  Masato Mizoguchi

IPC: H04W72/04 ,  H04W16/28 ,  H04B17/11 ,  H04B17/318 ,  H04B7/06 ,  H04L5/00

CPC classification number: H04W72/046 ,  H04B7/0617 ,  H04B17/11 ,  H04B17/318 ,  H04L5/0098 ,  H04W16/28 ,  H04W72/0453

Abstract: A wireless communication apparatus includes a designation unit which generates format designation information for designating a format of transmission and reception for another wireless communication apparatus, a first transmission unit which wirelessly transmits the format designation information to the other wireless communication apparatus, an acquisition unit which acquires a packet, a propagation channel estimation unit which estimates uplink propagation channel information indicating a propagation channel from the other wireless communication apparatus to the wireless communication apparatus based on the packet, a calibration coefficient calculation unit which calculates a calibration coefficient based on downlink propagation channel information indicating a propagation channel from the wireless communication apparatus to the other wireless communication apparatus and the uplink propagation channel information, a transmission weight value calculation unit which calculates a transmission weight value based on the calibration coefficient and the uplink propagation channel information, and a second transmission unit which wirelessly transmits a predetermined signal to the other wireless communication apparatus based on the transmission weight value.

公开(公告)号：US11979898B2

公开(公告)日：2024-05-07

申请号：US17596160

申请日：2020-05-28

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Tomohiro Tokuyasu ,  Hiroyuki Furuya ,  Hayato Fukuzono ,  Yu Ono ,  Tsutomu Tatsuta ,  Tomohiro Nakayama

IPC: H04W72/542 ,  H04W72/23

CPC classification number: H04W72/542 ,  H04W72/23

Abstract: A wireless communication system includes a plurality of sets of base station devices and terminal station devices configured to perform communications in an equal frame length using a time division duplex scheme, the communications of the plurality of sets being simultaneously operated in adjacent areas, in which each of the base station devices includes a control unit configured to control a transmission timing of a downlink signal transmitted from the base station device itself based on a communication distance between the base station device and the terminal station device of each of the sets or a reception timing of a downlink signal in the terminal station device such that reception timings of downlink signals transmitted from the base station device itself and other base station devices in the terminal station devices of the sets fall within a predetermined range determined in advance.

公开(公告)号：US11901980B2

公开(公告)日：2024-02-13

申请号：US17909161

申请日：2020-03-19

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Keita Kuriyama ,  Hayato Fukuzono ,  Masafumi Yoshioka ,  Takafumi Hayashi

IPC: H04B7/04 ,  H04B7/0456

CPC classification number: H04B7/0456

Abstract: A wireless communication method in a wireless communication system which includes a radio transmitting station apparatus having a plurality of antennas and a radio receiving station apparatus having an antenna and which performs transmission and reception of a radio signal with a single carrier, the wireless communication method including: the radio receiving station apparatus or the radio transmitting station apparatus estimating a communication path matrix based on a training signal; the radio receiving station apparatus or the radio transmitting station apparatus transforming the communication path matrix into a frequency domain, calculating a pseudo inverse matrix for each frequency with respect to the transformed frequency domain communication path matrix, and transforming the calculated pseudo inverse matrix into a time domain and adopting as a transmission weight matrix; and the radio transmitting station apparatus forming a transmission beam based on the transmission weight matrix.

公开(公告)号：US11736168B2

公开(公告)日：2023-08-22

申请号：US17636180

申请日：2019-09-06

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Keita Kuriyama ,  Hayato Fukuzono ,  Masafumi Yoshioka ,  Tsutomu Tatsuta

IPC: H04B7/06 ,  H04B7/0413

CPC classification number: H04B7/0617 ,  H04B7/0413

Abstract: A transmitting station device at least comprises a training signal generation unit, and a receiving station device at least comprises a communication path estimation unit which estimates a communication path response from the known signal, and a beam forming unit which performs a beam forming process using a weight to suppress inter-stream interference, a channel fluctuation amount calculation unit which calculates as a channel fluctuation amount a difference between the communication path responses estimated in a manner of one following another in time, and a weight calculation unit which calculates a new weight using an updated value of the weight calculated based on the channel fluctuation amount are included in one of the transmitting station device and the receiving station device. This can significantly reduce the amount of calculation related to update of a weight.