Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Sony Corporation

Thomson Licensing

Keijiro Take

Noriyuki Fukui

Masaaki Kusano

Kazuaki Ishioka

Toshiaki Tomisawa

Masao Oga

Shuuji Itou

Atsushi Okamura

Ryoichi Fujie

Yusuke Kinoshita

Tetsuya Aoyama

Akira Otsuka

Daichi Uchino

Syuji Ito

Ryo Matsunaga

Mitsuhiro Hashimoto

Keiko Sameshima

A satellite communication ground station as a satellite communication device performs communication control of a satellite backhaul link in a mobile communication system in which a ground base station and a core network device are connected via the satellite backhaul link, the satellite communication ground station including: a storage unit that stores a conversion table used in converting quality of service indicators that have different forms in the mobile communication system and the satellite backhaul link; and a quality of service indicator updating unit that updates priority of the quality of service indicator including priority of wireless communication of the satellite backhaul link in the conversion table on the basis of a result of evaluation of quality of service for each quality of service indicator.

Satellite communication device, core network device, control circuit, storage medium, and quality of service control method

An interface conversion device of a mobile communication system includes: a delay amount measurement unit that measures a delay amount from a difference between an input time at which the mobile communication system has acquired a periodically transmitted time-synchronization signal and an output time at which the mobile communication system outputs the time-synchronization signal; a memory that stores delay amount history information including the measured delay amount; a variation evaluation unit that measures a variation amount indicating an instantaneous variation of the delay amount, using the delay amount history information and evaluates whether the variation amount is within an allowable range; and an anomaly detection unit that detects a communication anomaly in the mobile communication system on the basis of a result of the evaluation.

Interface conversion device, control circuit, storage medium, and anomaly detection method

Provided are: a sending/receiving unit to receive data frames sent from another wireless station and receivable, the receivable data frames including a first data frame that is a relay target; an interference time storage unit to store an interference time that is a time from when the sending/receiving unit starts receiving each of the data frames to when the sending/receiving unit terminates receiving the data frame; a waiting time determination unit to determine a waiting time on a basis of the interference time; a frame generation unit to generate a second data frame by changing a destination of the first data frame to a data aggregation station that aggregates the data frames or to a wireless station that serves as a relay destination; and a transmission control unit to wait for the waiting time and cause the sending/receiving unit to send the second data frame.

Wireless station, data aggregation station, wireless system, transmission control method for wireless station, transmission control method for data aggregation, control circuit, and non-transitory storage medium

The present invention includes: a plurality of antenna sections, each of which to generate base station reception beams and to receive, by using the base station reception beams, one or more signals transmitted from a wireless terminal using one or more terminal transmission beams; a measurement unit that measures reception quality of each of the signals for each of the base station reception beams; and a control unit that groups the base station reception beams into groups in units of the antenna sections, and perform transmission power control on the terminal transmission beams of the wireless terminal in units of the groups, on the basis of a result of measurement of the measurement unit in units of the groups.

Radio base station, wireless terminal, radio communication system, transmission power controlling method, control circuit and program storage medium

A wireless terminal includes: an antenna that receives a plurality of beams formed by a radio base station; and a power control unit that adjusts transmission power of an uplink signal transmitted from the antenna to the radio base station after beam switching, on the basis of a reception power difference between a downlink signal of a beam used before the beam switching and a downlink signal of a beam to be used after beam switching, the beam switching being switching of a beam used for communication with the radio base station among the beams formed by the radio base station.

Wireless terminal, transmission power control method of wireless terminal, and radio base station

A wireless control apparatus controls beamforming performed by a wireless base station apparatus that provides a communication service to a service area which includes a plurality of spots to be irradiated with a beam including a terminal search beam and a communication beam that are not used simultaneously for irradiation, and is irradiated with a plurality of the beams and is not simultaneously covered by the plurality of beams, and the apparatus includes: an arrival direction estimation unit that estimates an arrival direction of a wireless signal transmitted by a terminal communicating with a wireless base station; and a control unit that determines whether there is an active terminal in the spots on the basis of the arrival direction estimated by the arrival direction estimation unit, and, when it is determined that there is no active terminal, controls beamforming performed by the wireless base station apparatus to decrease a frequency of the terminal search beam with which one or more of the spots determined to include no active terminal is irradiated and increases a frequency of a communication beam with which another of the spots in the service area is irradiated.

Wireless control apparatus

Provided is a beam transmission/reception method, which is executed in a wireless communication system in which a terminal and a base station use a beam to communicate to and from each other. The method includes a step of grouping, by the base station, when the base station is to receive a random access channel signal transmitted as a connection request from the terminal, a plurality of beam directions by combining a main beam direction, which is determined as suitable for reception of the random access channel signal, with one or more beam directions adjacent to the main beam direction, and of receiving the random access channel signal with use of the grouped plurality of beam directions.

Beam transmission-reception method, base station, terminal, and wireless communication system

A base station that communicates with a mobile station that intermittently performs a receiving operation during a cyclic reception period includes: an assignor that assigns a preamble to the mobile station; a start request signal generator that generates a start request signal containing the preamble assigned to the mobile station and requesting the start of a synchronization process between the mobile station and the base station; and a beam controller that transmits start request signals in a plurality of directions within the reception period while switching directions of directional beams for transmitting start request signals, and determines the direction of the directional beam for communicating with the mobile station, in accordance with the direction of the directional beam at the time of reception of the preamble transmitted from the mobile station having received the start request signal.

Base station, mobile station, and communication method

Provided is a beam transmission/reception method, which is executed in a wireless communication system in which a terminal and a base station are configured to use a beam to communicate to and from each other. The beam transmission/reception method includes a first step of setting, by the base station, when receiving a random access signal transmitted by the terminal as a connection request, a beam direction group at a time of reception of the random access signal by adding a further outer beam direction to beam directions used at a time of transmission of a notification signal for measuring a signal before the reception.

Beam transmission/reception method, base station, terminal, and wireless communication system

When a mobile device performs a handover from a first wireless base station to a second wireless base station, a base station controller sends a control message addressed to the second base station to notify the handover, to the first wireless base station via a wired line. The first wireless base station sends received control message to the second wireless base station using a pre-established wireless line. The wireless base stations exchange a control message to control the second wireless base station, a control message to control the mobile device, and user data of the mobile device and a communication partner, using the wireless line.

Handover method in a wireless access network

In a radio access network in which a radio network controller is subjected to load distribution by a plurality of controllers, one of the controllers is set as a page controller that processes a paging message transmitted from a core network to the radio access network. When the paging control apparatus receives the paging message transmitted from the core network to the radio access network, the paging control apparatus judges a transmission destination of the paging message and transmits the paging message to the controllers that control a base station at the transmission destination.

Paging control method, paging control apparatus, and radio access network

A base station controller selects codes corresponding to rate information included in a new starting call message from a mobile station, and further selects codes assignable to the mobile station from the selected codes as candidate codes. Then, the base station controller detects codes which meet both the characteristics of being at a higher level of the candidate codes in the tree structure and being assignable to other mobile stations, and further detects levels of the detected codes. Detected levels for all the candidate codes are compared to find a candidate code whose level is the lowest and to assign the candidate code to the mobile station sending the new staffing call message.

Radio communication system and base station employing CDMA

A base station controller selects codes corresponding to rate information included in a new starting call message from a mobile station, and further selects codes assignable to the mobile station out of the selected codes as candidate codes. Then, the base station controller detects codes which meet both the characteristics of being at upper level of the candidate codes in the tree structure and being assignable to other mobile station, and further detects levels of the detected codes. Detected levels for all the candidate codes are compared to find a candidate code whose level is the lowest and to assign the candidate code to the mobile station sending the new starting call message.

Growing community of inventors

Tokyo, Japan

Keijiro Take