Hitachi, Ltd.

Hajime Kanzaki

Mikio Kuwahara

Koichiro Furueda

Tsukasa Sasayama

Daisuke Ishii

Satoshi Tamaki

Kenzaburo Fujishima

Katsuhiko Tsunehara

Toshiyuki Saito

Eriko Takeda

Nobuyuki Muranaka

Tatsunori Ohara

Kenichi Azuma

A work support apparatus, which assigns an operator to an operation performed in a workplace, includes a communication device used for the operation in the workplace, and holds information on a relationship between a process, an operation, and each of divided areas of the workplace and the communication device used for the operation, information on a predicted communication throughput by the communication device in each of the divided areas, and information on an operator-requested communication throughput for a combination of the operation and an operator. For each operation corresponding to the process, the apparatus determines assignment of an operator to the operation, referring to the predicted communication throughput by the communication device and the operator-requested communication throughput, and outputs a result of the operator assignment.

Work support apparatus and work support method

A gateway device is wirelessly connected to a mobile device and a control device that is connected to the gateway device and controls the mobile device. The mobile device reports a completion report indicating completion of a movement work according to a movement control instruction from the control device, and wherein the control device includes a work control unit that transmits the movement control instruction to the mobile device. It is determined whether or not a failure has occurred in communication between the control device and the gateway device, and it is determined whether or not the movement control instruction executed by the mobile device passes through the gateway device in which the failure determined by the failure detection unit has occurred, and stops transmission of the movement control instruction of passing through the gateway device in which the failure has occurred to the mobile device.

System for controlling mobile device, control device, and control method

Provided is a wireless communication system which includes a wireless communication unit using plural frequency bands and plural antennas. The system changes the transmission power of each antenna, based on the interference of each of the frequency bands from the neighbor base station along the antenna direction. The system estimates the number of antennas necessary for transmission in response to a user requirement, and determines a necessary antenna in accordance with the antenna direction in which the terminal is located, and further changes the transmission power of each antenna.

Wireless base station for controlling antenna transmission power

Necessary transmission power of terminals is secured while suppressing total transmission power in base station, so that FFR technology is realized with high frequency utilization efficiency to thereby realize both of compactness of base station and increase of communication capacity. Frequency resource is divided into frequency for boundary area of cell and frequency for central area of cell. Transmission power per unit frequency is fixed in the frequency for boundary area of cell and is set to be variable in the frequency for central area of cell. Transmission power per unit frequency is adjusted so as to satisfy necessary power of terminals connected to frequency for central area of cell. When it is judged that total transmission power of base station exceeds prescribed value, terminal is moved from central area to boundary area of cell, so that total transmission power is suppressed to be equal to or smaller than standard.

Transmission power adjustment method in wireless communication system and base station

A radio communication system is provided in which, based on a measurement condition and neighbor information specified by a base station to which a mobile terminal is connected, the mobile terminal measures the reception quality of the neighboring base stations included in the neighbor information and, when a transmission request is received from the connected base station, transmits the measurement result to the connected base station. In this radio communication system, the base station transmits neighbor information, which specifies the base stations for which interference measurement is to be performed, and a measurement result transmission request to the mobile terminal at a predetermined time for measuring the interference of neighboring base stations and, in response to it, the mobile terminal transmits the measurement result of the base stations, specified by the base station for measuring the interference, to the base station.

Radio base station, radio communication system and interference notifying method in radio communication system

In a cellular radio communication system including of multi-antenna base stations, to make effective use of the reduced interference in supposing the use of beam form and avoid the interference in an adjacent station even if a space multiplex and the beam form are mixed. Frequencies intended for the cell edge in an FFR are classified into frequencies for space multiplex and a frequency for beam form. Thereby, a frequency at which the interference is reduced by the beam form is fixed. A frequency intended for the cell center is in a frequency band and signals are transmitted from three base stations.

Cellular radio communication system, radio base station apparatus and radio terminal unit

When DFFR is performed in a heterogeneous environment in which a pico base station coexists in the area of a macro base station and when the pico base station judges that, based on the received-signal quality report result from a mobile terminal, the macro base station causes interference to the pico base station, the pico base station reports an interference power threshold to be notified to the macro base station based on the transmission power setting value of the macro base station, the transmission power setting value of the pico base station, and the estimated interference amount calculated from the scan report result. The macro base station transmits a result of comparison between the transmission powers of multiple frequency resources and the interference power threshold, to the pico base station and the pico base station selects a frequency resource, unlikely to be affected by interference.

Radio communication system, radio communication method and base station

In a conventional cellular wireless communication system that included a plurality of base station apparatuses having a plurality of antennas, just two antennas were used for simultaneous transmission by transmission diversity, and the antenna usage efficiency was low. According to the present invention, a free transmission diversity antenna for transmission to the edge of a cell is used to send a signal to a terminal located around the center of the cell without causing interference to a terminal located around the edge of the cell. The two terminals located around the edge of the cell and around the center of the cell are paired for simultaneous signal transmission. A signal directed to the edge of the cell and a signal directed to the center of the cell are sent with greatly different transmission power. This reduces the interference caused by the signal directed to the center of the cell to an insignificant level for the terminal located around the edge of the cell. The terminal located around the edge of the cell does not appear to be affected by interference from signal transmission to the center of the cell and does not have to always use four antennas.

Wireless communication system and method, and base station apparatus

A wireless communication apparatus comprising a memory for storing a group of coefficient values to be applied to processing of orthogonal modulation signals received by a plurality of antenna elements, a coefficient generation unit for detecting a phase shift value of reception timing of specific received signals on the basis of a desired signal and the coefficient values read out from the memory, compensating the group of coefficient values according to the detected phase shift value, and storing the compensated coefficient values in the memory, and a signal processing unit for processing the received signals by applying the compensated coefficient values.

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Hiratsuka, Japan

Hajime Kanzaki