Nippon Telegraph and Telephone Corporation

Ntt Corporation

Takatsune Moriyama

Kenichi Kawamura

Yasushi Takatori

Shota Nakayama

Keisuke Wakao

Koichi Ishihara

Daisuke Murayama

Akira Kishida

Toshiro Nakahira

Tomoyuki Yamada

Wataru Yamada

Motoharu Sasaki

Nobuaki Kuno

A communication system includes a terminal that communicates with a base station wirelessly; and a control device, in which the terminal includes a transmitter that transmits information on a location of the terminal, and the control device includes a processor; and a memory that includes instructions, which when executed, cause the processor to execute the following steps: acquiring the information on the location of the terminal, predicting a future location of the terminal based on the information on the location of the terminal and determining whether the terminal is to enter a dead zone by comparing the future position with the dead zone, and executing control for switching a connection destination of the terminal when the determining determines that the terminal is to enter the dead zone.

Communication system, connection destination control method, control apparatus and program

A communication system includes a terminal configured to wirelessly communicate with a base station, a plurality of IoT terminals, and a control device. The control device includes a processor; and a memory that includes instructions, which when executed, cause the processor to execute the following steps: selecting an IoT terminal around a dead zone and transmitting a command of signal transmission to the selected IoT terminal. The selected IoT terminal includes a receiver configured to receive the command, and a transmitter configured to transmit a signal according to the command. The terminal receiving the signal transmitted from the selected IoT terminal performs a connection operation for avoiding the dead zone.

Communication system, connection designation control method, control apparatus and program

A radio signal strength information calculation method performed by a control apparatus includes: calculating radio information regarding each of a plurality of meshes into which an area where base stations are placed is divided and generating mesh radio information; and placing a virtual base station at a position to where any of the base stations would be moved in the area, and calculating radio signal strength information between a plurality of base stations including the base stations and the virtual base station based on the mesh radio information.

Radio signal strength information calculation method, control apparatus and program

A wireless LAN system where an interfering communication device is present around a base station device and a terminal device includes an interference control signal transmitter that transmits an interference control signal that causes the interfering communication device to wait for transmission, and an interference control signal management device that collects wireless environment information, sets wireless LAN communication between the base station device and the terminal device, which are protection targets, as protected communication, and causes the interference control signal transmitter to transmit an interference control signal that causes the interfering communication device to wait for transmission, and the interference control signal management device instructs the interference control signal transmitter to start transmitting the interference control signal when detecting a start of the protected communication and instructs the interference control signal transmitter to stop transmitting the interference control signal when detecting a stop of the protected communication.

Provide a wireless local area network (LAN) system, an interference control signal management device which are capable of limiting interference

An embodiment of the present invention is a local wireless communication system that emits a radio wave in a licensed band to form a wireless communication environment in a predetermined area. The system includes a base station configured to emit a radio wave, a plurality of sensors disposed along an edge of the area, and a control apparatus. The sensors each measure a radio field intensity of the radio wave emitted from the base station, and feed the radio field intensity back to the control apparatus via the base station. The control apparatus controls a transmission power of the radio wave from the base station to control the fed radio field intensity.

Local wireless communication system, radio field intensity control method, control device, and program

Provided are: an extraction unit that, based on input information from an external source, extracts position information regarding a transmitting station and a receiving station and the frequency of radio waves transmitted by the transmitting station; a calculation unit that calculates the three-dimensional distance between the transmitting station and the receiving station and the free space loss of radio waves based on the position information and the frequency; a processing unit that performs processing for, with use of a two-dimensional image of a region that includes the transmitting station and the receiving station, extracting the edges of structures that reflect radio waves in the two-dimensional image; a generation unit that generates input data for use in machine learning, based on the position information, the three-dimensional distance, the free space loss, and the edge; and a learning unit that performs machine learning to estimate the propagation characteristics of radio waves between the transmitting station and the receiving station with use of the input data generated by the generation unit.

Propagation characteristic estimation device, propagation characteristic estimation method, and propagation characteristic estimation program

Provided is a wireless communication system that performs priority control by setting, depending on a type of transmission data, a channel use period during which exclusive use of a channel after a right to access the channel is acquired is permitted. The wireless communication system includes a measurement unit that measures quality measurement information related to a quality of wireless communication, a parameter setting unit that makes, when a latency in transmission of a prioritized frame due to transmission of a non-prioritized frame is not expected based on the quality measurement information measured by the measurement unit, settings such that the channel use period for the transmission of the non-prioritized frame is changed to be longer, and a MAC frame generation unit that generates a MAC frame which permits continuous transmission of the non-prioritized frames within the channel use period set by the parameter setting unit.

System and method for performing priority control in wireless communication

In a random access radio communication system configured to perform downlink communication from a radio base station to radio terminals by random access, the radio terminals include one or more low latency terminals requiring low latency and one or more non-low latency terminals not requiring low latency, and the low latency terminals and the non-low latency terminals are configured to be distinguished by service set identifiers (SSIDs). The random access radio communication system includes terminal assignment destination control unit of distinguishing the low latency terminals and the non-low latency terminals in accordance with the SSIDs and evenly distributing the terminals into a plurality of communication channels, and random access control unit of performing priority control on the low latency terminals and the non-low latency terminals for each communication channel so that the downlink communication in the low latency terminal satisfies a predetermined delay time.

Growing community of inventors

Musashino, Japan

Takatsune Moriyama