公开(公告)号：US20160028467A1

公开(公告)日：2016-01-28

申请号：US14771822

申请日：2013-03-08

Applicant: Hitachi, Ltd.

Inventor： Ryosuke FUJIWARA ,  Makoto KATAGISHI ,  Masayuki MIYAZAKI

IPC: H04B7/14 ,  H04L12/741 ,  H04W28/20 ,  H04W72/04 ,  H04W74/06

CPC classification number: H04B7/14 ,  H04B7/155 ,  H04B7/2656 ,  H04L45/021 ,  H04L45/745 ,  H04W28/20 ,  H04W72/0446 ,  H04W74/06 ,  H04W84/18 ,  H04W88/02 ,  H04W88/08

Abstract: An object of the disclosed invention is to provide a polling-based multihop communication system capable of achieving robust communication. Solving means thereof is a (multihop communication) wireless transmission system including, as wireless stations, a base station, a plurality of relay stations connected at multiple stages by using the base station as a root, and a plurality of terminals connected to the relay stations, in which the base station and the relay stations perform communication using polling in one or more service periods which have been allocated to each of the base and relay stations in time division in advance in a system cycle.

Abstract translation: 所公开的发明的目的是提供一种能够实现鲁棒通信的基于轮询的多跳通信系统。 其解决方法是一种（多跳通信）无线传输系统，其包括作为无线站的基站，通过使用基站作为根而在多个阶段连接的多个中继站，以及连接到中继站的多个终端 其中，所述基站和所述中继站在系统周期中预先分时地分配给每个基站和中继站的一个或多个服务周期中进行轮询进行通信。

公开(公告)号：US20150036619A1

公开(公告)日：2015-02-05

申请号：US14445517

申请日：2014-07-29

Applicant: HITACHI, LTD.

Inventor： Haruki NISHIMURA ,  Ryosuke FUJIWARA ,  Makoto KATAGISHI ,  Masayuki MIYAZAKI

IPC: H04W74/06

CPC classification number: H04W72/12 ,  H04W68/00

Abstract: Provided is a wireless transmission system including a plurality of access points and an access controller. The access controller determines a start standard time for a polling period for the plurality of access points to perform polling communication with a plurality of wireless terminals. The access controller generates a scheduling setting information indicating timings when the plurality of access points perform polling communication with the plurality of wireless terminals during the polling period. The access controller transmits, to each of the plurality of access points, a polling period start signal including the start standard time and a corresponding portion of the scheduling setting information for each of the plurality of access points. The plurality of access points perform polling communication with the plurality of wireless terminals based on respective polling period start signals.

Abstract translation: 提供了包括多个接入点和接入控制器的无线传输系统。 访问控制器确定多个接入点的轮询周期的开始标准时间，以执行与多个无线终端的轮询通信。 访问控制器产生调度设置信息，该调度设置信息指示当多个接入点在轮询期间执行与多个无线终端的轮询通信时的定时。 访问控制器向多个接入点中的每一个发送包括开始标准时间的轮询周期开始信号和针对多个接入点中的每一个的调度设置信息的对应部分。 多个接入点基于相应的轮询周期开始信号来执行与多个无线终端的轮询通信。

公开(公告)号：US20200272516A1

公开(公告)日：2020-08-27

申请号：US16789472

申请日：2020-02-13

Applicant: Hitachi, Ltd.

Inventor： Rintaro KATAYAMA ,  Ryosuke FUJIWARA ,  Kenichi MIZUGAKI

IPC: G06F9/48 ,  G01V1/00 ,  G01M3/00

Abstract: A processor 204 of a sensor device performs measurement processing by one or a plurality of sensors 203 and transmission processing of sensor data generated by the measurement processing. The sensor device includes a processing routine table 211 that stores a processing routine configured to include, corresponding to an identifier for identifying processing performed by a processor, a type of the processing, an execution trigger of the processing, and trigger information that prescribes a trigger for transmitting the sensor data. The processor controls processing in a processing routine of the processing routine table, based on trigger information, so that the sensor data subjected to measurement processing is immediately transmitted, or temporarily stored in a buffer 212 and transmitted after a predetermined time.

公开(公告)号：US20230396348A1

公开(公告)日：2023-12-07

申请号：US18201227

申请日：2023-05-24

Applicant: Hitachi, Ltd.

Inventor： Ken TAKEI ,  Masami OHNISHI ,  Ryosuke FUJIWARA

IPC: H04B17/391 ,  H04W24/06

CPC classification number: H04B17/3912 ,  H04W24/06

Abstract: An objective of the present invention is to use a calculation model to calculate, with good accuracy, behavior of electromagnetic waves within an actual service area. Provided is a radio environment evaluation method that includes constructing, within a computer resource, a structural model for an electromagnetic wave scatterer, and when calculating a characteristic of an electromagnetic field by using the structural model and a ray that simulates a radio wave traveling straight through real space, correcting, in accordance with electromagnetic wave vector measurement data for real space, a state of a polygon included in the structural model.

公开(公告)号：US20240215006A1

公开(公告)日：2024-06-27

申请号：US17911765

申请日：2022-02-14

Applicant: Hitachi, Ltd.

Inventor： Hiromu KAMEI ,  Mikio KUWAHARA ,  Ryo NAKANO ,  Ryosuke FUJIWARA

IPC: H04W72/0457 ,  H04L45/851 ,  H04W28/04 ,  H04W48/18

CPC classification number: H04W72/0457 ,  H04L45/851 ,  H04W28/04 ,  H04W48/18

Abstract: To determine a communication path satisfying communication requirements depending on an operation of an application, it is provided a management device for selecting a communication path that satisfies communication requirements for an application operating on a terminal, the management device comprising: an event detection module configured to detect, as an event, one of an operation change, an increase, or a decrease of the application which is accompanied by a change in the communication requirements; app information for managing the communication requirements for each operation of the application; communication path information for managing communication quality of each communication path; and a communication control method calculation module configured to determine, by referring to the app information and the communication path information, a communication control method that satisfies the communication requirements for the application from which the event has been detected, and notify a communication control device of the determined communication control method.

公开(公告)号：US20210377777A1

公开(公告)日：2021-12-02

申请号：US17326013

申请日：2021-05-20

Applicant: Hitachi, Ltd.

Inventor： Rintaro KATAYAMA ,  Daisuke ISHII ,  Ryosuke FUJIWARA

IPC: H04W28/02 ,  H04W4/40 ,  H04L12/851

Abstract: A receiver mounted on a vehicle moving on a route manages an operation profile that stores data in which a section that is a part of the route and a communication quality in the section are associated, and can receive a first traffic and a second traffic having a lower priority than the first traffic. The receiver determines a section having a good communication quality to a transmission section where the second traffic can be transmitted with reference to the operation profile, and generates control information for controlling transmission of the second traffic not to hinder transmission of the first traffic when the vehicle is located in the transmission section.

公开(公告)号：US20170230310A1

公开(公告)日：2017-08-10

申请号：US15518832

申请日：2014-12-12

Applicant: HITACHI, LTD.

Inventor： Takashi TAKEUCHI ,  Masayuki MIYAZAKI ,  Ryosuke FUJIWARA

IPC: H04L12/939 ,  G06F11/14 ,  H04L1/00

CPC classification number: H04L1/0026 ,  H04L1/0009 ,  H04L1/1671 ,  H04L1/20

Abstract: Provided are a device, a system, and a method in which redundancy is changed in accordance with a line state, and thus the optimal redundancy can be set while the current settings are compared to the previous settings. A communication device measures line quality information from a received packet, and generates a redundancy change instruction based on information regarding a line. In a case where the communication device acquires line quality information for the second and subsequent times, the communication device compares the previous redundancy change instruction and the previous line quality information, to the current line quality information, and sets redundancy. Thus, it is possible to suppress the occurrence of congestion and satisfy a target value of the line quality, and to search for a condition which causes the redundancy to be the minimum.

公开(公告)号：US20240235707A1

公开(公告)日：2024-07-11

申请号：US18572496

申请日：2022-06-21

Applicant: Hitachi, Ltd.

Inventor： Masami OONISHI ,  Ryosuke FUJIWARA ,  Ken TAKEI

IPC: H04B17/391 ,  H04B17/354 ,  H04W16/18

CPC classification number: H04B17/3912 ,  H04B17/354 ,  H04W16/18

Abstract: A radio wave propagation simulation system is constituted with a computer including an arithmetic device that executes predetermined arithmetic processing and a storage device connected to the arithmetic device, and includes a model generation unit which generates a radio wave propagation model by the arithmetic processing of the arithmetic device, and the model generation unit generates a plurality of planes that simulate one surface of a structure, defines, as an attribute of each of the planes to be generated, a unit normal vector representing an orientation of each of the planes and generates a radio wave propagation model constituted with the generated planes.

公开(公告)号：US20210013616A1

公开(公告)日：2021-01-14

申请号：US16908906

申请日：2020-06-23

Applicant: Hitachi, Ltd.

Inventor： Masami OONISHI ,  Kenichi MIZUGAKI ,  Rintaro KATAYAMA ,  Ryosuke FUJIWARA

IPC: H01Q13/12 ,  H01Q13/18 ,  H01Q1/38 ,  E02D29/14

Abstract: An antenna device includes a conductive manhole cover for partitioning an internal space of a manhole and an external space, a wireless device installed in the internal space, and a base station that is installed in the external space and transfers a radio wave with respect to the wireless device. When a notch portion is formed on the edge of the manhole cover and the manhole cover is attached to an opening of the manhole, a slot-shaped void is formed. By using this void as a slot antenna, radio waves from the wireless device can be re-emitted to the external space. With such a configuration, it is not necessary to specially prepare a slot antenna, and a low-cost antenna device can be realized.

公开(公告)号：US20190310158A1

公开(公告)日：2019-10-10

申请号：US16251580

申请日：2019-01-18

Applicant: HITACHI, LTD.

Inventor： Kazuo ONO ,  Yuudai KAMADA ,  Ryosuke FUJIWARA ,  Takashi ENDO

IPC: G01M3/24 ,  G06F17/14 ,  G06F17/15

Abstract: A monitoring system includes a plurality of sensor terminals installed for a target to be measured, a base station wirelessly communicating with the sensor terminals, and a calculator communicable with the base station. The sensor terminal includes a sensor element which acquires vibration information of a target to be measured, an arithmetic unit which performs an arithmetic operation for data including the vibration information of the sensor element, and a wireless communication unit. The arithmetic unit performs a reduction process for reducing an amount of data of the sensor element. The wireless communication unit transmits data processed by the arithmetic unit to the base station. After the transmitted data is received, the base station transmits it to the calculator. The calculator includes a signal processing unit. The signal processing unit complements the reduction-processed data to acquire vibration information, and averages the vibration information for a predetermined period of time.