Abstract: A terminal device is provided and includes a location information acquisition device configured to acquire location information including a location of the terminal device, a storage configured to accumulate history information on past communication status including a communication time of the terminal device at each location, and a controller configured to acquire the history information for a current location of the terminal device from the storage based on the location information, to extract one or more connection destinations as targets of communication quality measurement from connection destination candidates based on communication times for the connection destination candidates, and to measure communication quality levels of communications with the extracted connection destinations.

Abstract: In order to quickly establish a communication link between a user terminal and an access point, a communication system comprises: a user terminal; an access point configured to transmit and receive user data to and from the user terminal; a cellular base station assisting wireless communication between the user terminal and the access point; and a control server 4. The user terminal comprises a cellular communicator configured to transmit location information of the user terminal to the control server via the cellular base station. The control server comprises a controller configured to generate communication control information; and a network communicator configured to transmit notification information including the communication control information. The access point comprises a beam controller configured to control a beam pattern used for wireless communication between the access point and the user terminal based on the communication control information.

Abstract: A base station includes a memory holding information on P terminals in connecting to the base station, where P is an integer of 3 or more, a determination unit that determines L terminals to transmit a reference symbol used for measurement of channel state information indicating a state of a propagation path to the base station from among the P terminals based on the information on the P terminals, at every data transmission cycle, where L is an integer satisfying 2?L<P, a selector that selects M terminals capable of spatial multiplexing communication in the data transmission cycle based on a measurement result of the channel state information based on reception of the reference symbol transmitted from L terminals, where M is an integer satisfying 2?M?L, and receives respective pieces of data transmitted from the M terminals via a plurality of antennas.

Abstract: A wireless system includes a plurality of base stations including a first base station connected to a backbone network and a plurality of second base stations connected to the first base station by wireless multi-hop, and a server disposed in the backbone network and communicating with the first base station.

Abstract: A base station is capable of wireless communication with a plurality of terminals, the base station includes a memory that holds information on P (P: an integer of 3 or more) terminals currently connected to the base station, a determination unit that determines L (L: an integer satisfying 2?L<P) terminals that are to report channel state information indicating a state of a propagation path to the base station from among the P terminals based on the information on the P terminals, at every data transmission cycle, a selector that selects M (M: an integer satisfying 2?M?L) terminals capable of spatial multiplex communication in the data transmission cycle based on the reporting of the channel state information from the L terminals, and a communicator that transmits data to and from the M terminals via a plurality of antennas using the spatial multiplex communication.

Abstract: In order to shorten a waiting time until a user terminal receives a down signal transmitted from a base station apparatus and ensure that a transmission beam is transmitted to a direction towards where one or more user terminals are present, a base station for time-divisionally transmitting a down signal to multiple user terminals present in a cell concurrently with changing a transmission beam direction where the down signal is common to the multiple user terminals is provided and includes a wireless communicator configured to time-divisionally transmit the down signal concurrently with changing the transmission beam direction, an information storage configured to store transmission schedule information which specifies transmission timing of the transmission beam, and a controller configured to control, based on the transmission schedule information, the transmission beams when the base station transmits the down signal.

Abstract: A communication device is provided and includes: a wireless communication device configured to wirelessly communicate with a base station used as a connection destination; a location information acquisition device configured to acquire location information on a location of the communication device; a storage configured to store historical obstruction information for an obstructed location where decrease in communication quality due to obstruction has occurred before; a controller configured to determine, based on the historical obstruction information and the location information, a degree of risk of occurrence of decrease in communication quality due to obstruction for at least one of a current connection destination that is currently used by the communication device and a future connection destination that is expected to be used by the communication device, and control the connection destination based on a result of determination of the degree of risk.

Abstract: In order to properly control a communication bandwidth used for communication without increasing load of a network, a communication device includes a controller configured to control a communication bandwidth used for transmitting application data by using a congestion control algorithm, wherein, when a connection destination is changed, the controller acquires an initial value of the communication bandwidth appropriate for the connection destination based on an initial value table, and starts control of the communication bandwidth by using the initial value.

Abstract: To shorten time required to measure communication quality levels, a terminal device selects one of a first or second measurement scheme based on an amount of available bandwidth provided by a current cell in which the terminal device is currently present and other information. When the current cell is provides a largest amount of available bandwidth, the terminal device selects the first scheme, and when the current cell provides a smallest amount of available bandwidth, the terminal device selects the second scheme. When the first scheme is selected, the terminal device measures communication quality levels of communication with all peripheral cells, and when the second scheme is selected, the terminal device acquires current location information on the terminal device, and then extracts one or more of the peripheral cells based on current location information and historical communication information, and measures communication quality levels of communication with the extracted peripheral cells.

Abstract: To shorten time required to measure communication quality levels, a terminal device selects one of a or second measurement scheme based on an amount of available bandwidth provided by a current cell in which the terminal device is currently present and other information. When the current cell is provides a largest amount of available bandwidth, the terminal device selects the first scheme, and when the current cell provides a smallest amount of available bandwidth, the terminal device selects the second scheme. When the first scheme is selected, the terminal device measures communication quality levels of communication with all peripheral cells, and when the second scheme is selected, the terminal device acquires current location information on the terminal device, and then extracts one or more of the peripheral cells based on current location information and historical communication information, and measures communication quality levels of communication with the extracted peripheral cells.

Abstract: To allow for selection of a connection-destination suitable for an application when switching from one connection-destination to another, or adding or deleting a connection-destination, a base station apparatus is configured to generate connection-destination candidate information on base station apparatuses as connection-destination candidates connectable to a terminal apparatus, and transmit to the terminal apparatus a connection-destination candidate notification control message including the connection-destination candidate information, and the terminal apparatus selects a new base station apparatus to be used as a new connection-destination based on the connection-destination candidate information and a communication condition required by a user application section, the user application section being configured to perform information processing required by a user concurrently with performing wireless communication.

Abstract: A base station includes a memory holding information on P terminals in connecting to the base station, where P is an integer of 3 or more, a determination unit that determines L terminals to transmit a reference symbol used for measurement of channel state information indicating a state of a propagation path to the base station from among the P terminals based on the information on the P terminals, at every data transmission cycle, where L is an integer satisfying 2?L<P, a selector that selects M terminals capable of spatial multiplexing communication in the data transmission cycle based on a measurement result of the channel state information based on reception of the reference symbol transmitted from L terminals, where M is an integer satisfying 2?M?L, and receives respective pieces of data transmitted from the M terminals via a plurality of antennas.

Abstract: In order to enable efficient utilization of an available bandwidth by properly estimating the available bandwidth under conditions in which the available bandwidth significantly changes upon occurrence of communication path switching, an available bandwidth estimation is performed by estimating a current available bandwidth based on historical communication state information i.e.

Abstract: A wireless terminal that: for previous communications between the wireless terminal and base stations, stores as a communication history at least position information for the wireless terminal and information pertaining to each base station; acquires the position information for the wireless terminal and, on the basis of the position information for the wireless terminal and the stored communication history, derives from multiple base stations at least a connection subject base station to be used in data communication and a connection standby base station, which is the base station having the next highest connection priority after the connection subject base station; and performs data communication when a trial connection with the connection subject base station has succeeded, and switches the connection subject base station to be used in data communication to the connection standby base station when communication with the connection subject base station is interrupted.

Abstract: A base station is capable of wireless communication with a plurality of terminals, the base station includes a memory that holds information on P (P: an integer of 3 or more) terminals currently connected to the base station, a determination unit that determines L (L: an integer satisfying 2?L<P) terminals that are to report channel state information indicating a state of a propagation path to the base station from among the P terminals based on the information on the P terminals, at every data transmission cycle, a selector that selects M (M: an integer satisfying 2?M?L) terminals capable of spatial multiplex communication in the data transmission cycle based on the reporting of the channel state information from the L terminals, and a communicator that transmits data to and from the M terminals via a plurality of antennas using the spatial multiplex communication.

Abstract: A wireless terminal capable of communicating with multiple wireless base stations through a network in which multiple wireless communication methods are used in a mixed manner. A storage unit stores, as a communication history, at least location information for the wireless terminal and information pertaining to the wireless base station at the time of communication with each wireless base station. An acquisition unit acquires the location information for the wireless terminal. On the basis of the acquired location information for the wireless terminal and the communication history stored in the storage unit a derivation unit derives a connection base station from the multiple wireless base stations, as the wireless base station to be used in data communication. A communication unit performs data communication with the derived connection base station.

Abstract: In order to shorten a waiting time until a user terminal receives a down signal transmitted from a base station apparatus and ensure that a transmission beam is transmitted to a direction towards where one or more user terminals are present, a base station for time-divisionally transmitting a down signal to multiple user terminals present in a cell concurrently with changing a transmission beam direction where the down signal is common to the multiple user terminals is provided and includes a wireless communicator configured to time-divisionally transmit the down signal concurrently with changing the transmission beam direction, an information storage configured to store transmission schedule information which specifies transmission timing of the transmission beam, and a controller configured to control, based on the transmission schedule information, the transmission beams when the base station transmits the down signal.

Abstract: While a primary user and a secondary user are possibly co-present, a resource is efficiently allocated to the secondary user, QoS at a fixed level is provided to the secondary user of the carrier that is given a license. Provided is controller 30: including a license determiner 301 that determines whether or not a license is given to a carrier that owns each base station 40 which requests resource allocation; an allocation propriety determiner 302 that determines whether or not it is possible to allocate a resource for a secondary service, based on a used situation of a primary service, and an allocation ratio determiner 303; and an allocation ratio determiner 303 that determines a ratio of resources that are allocated to the base stations 40 that are owned by the carrier which is given the license, based on a prescribed parameter, in a case where the resource allocation is possible.

Abstract: In order to quickly establish a communication link between a user terminal and an access point, a communication system comprises: a user terminal; an access point configured to transmit and receive user data to and from the user terminal; a cellular base station assisting wireless communication between the user terminal and the access point; and a control server 4. The user terminal comprises a cellular communicator configured to transmit location information of the user terminal to the control server via the cellular base station. The control server comprises a controller configured to generate communication control information; and a network communicator configured to transmit notification information including the communication control information. The access point comprises a beam controller configured to control a beam pattern used for wireless communication between the access point and the user terminal based on the communication control information.

Abstract: To allow for selection of a connection-destination suitable for an application when switching from one connection-destination to another, or adding or deleting a connection-destination, a base station apparatus is configured to generate connection-destination candidate information on base station apparatuses as connection-destination candidates connectable to a terminal apparatus, and transmit to the terminal apparatus a connection-destination candidate notification control message including the connection-destination candidate information, and the terminal apparatus selects a new base station apparatus to be used as a new connection-destination based on the connection-destination candidate information and a communication condition required by a user application section, the user application section being configured to perform information processing required by a user concurrently with performing wireless communication.