Kddi Corporation

Xiaoqiu Wang

Satoshi Konishi

Toshiaki Yamamoto

Yosuke Akimoto

Fumio Watanabe

Takeo Ohseki

Hailan Peng

Yasuhiro Suegara

Toshihiko Komine

Noriaki Miyazaki

Kouichiro Kitagawa

Yuji Ikeda

Makoto Konno

In a wireless communication system in which when connecting one terminal apparatus to a base station apparatus and another base station apparatus, the other base station apparatus selects a frequency band to be used for control channels transmitted from the terminal apparatus to the other base station apparatus from a plurality of frequency bands usable by the other base station apparatus, and notifies the terminal apparatus of the selected frequency band, the base station apparatus acquires from the terminal apparatus information about radio quality of a signal received from the other base station apparatus for at least one frequency band out of the plurality of frequency bands, extracts a portion of frequency bands out of the plurality of frequency bands based on the acquired information about radio quality, and notifies the other base station apparatus of information representing the portion of frequency bands.

Base station apparatus, control method, and storage medium

A base station device (E-UTRAN) assigns a frequency band unsupported by the base station device as a radio resource usable for terminal-to-terminal communication, and transmits resource information for designating the assigned radio resource to a first terminal device and a second terminal device.

Radio control device, terminal device, and communication method

A terminal device includes a wireless communication part configured to wirelessly communicate with base station devices; a link controller configured to establish a link with a primary base station device (PCell) so as to enable a wireless communication via the wireless communication part while establishing a link with a secondary base station device (SCell) so as to enable a wireless communication via the wireless communication part; a primary base station link failure detector configured to detect a radio link failure in the wireless communication with the primary base station device based on the predetermined condition; and a primary base station link failure information transmitter configured to wirelessly transmit the information, concerning the radio link failure with the primary base station device, to the secondary base station device when the primary base station link failure detector detects the radio link failure status.

Terminal device, base station device, communication system, and communication method

In a wireless communication system which can share the same frequency band with time division duplexing (TDD) and frequency division duplexing (FDD), a wireless terminal carries out an FDD downlink reception in a second frequency band overlapping a first frequency band allocated to TDD, thus carrying out reception at the TDD downlink reception timing. Alternatively, a wireless terminal carries out a TDD downlink reception in a second frequency band overlapping a first frequency band allocated to FDD, thus carrying out reception at the FDD downlink reception timing.

Wireless communication system and wireless communication method

A terminal device includes a wireless communication unit performing wireless communication; a connection control unit connecting to a first base station device to wirelessly communicate with the first base station device via the wireless communication unit, the first base station serving as a primary, the connection control unit connecting to a second base station device to wirelessly communicate with the second base station device via the wireless communication unit, the second base station device serving as a secondary; a detection unit determining whether quality of wireless communication between the terminal device and the first base station device is in a low state based on a predetermined condition; and a signal transmission control unit wirelessly transmitting via the wireless communication unit, a predetermined signal toward at least either the first or second base station device when the quality is determined to be in the low state by the detection unit.

Terminal device, base station device, communications system, and communications method

A communication control apparatus, in a wireless communication system having an area in which coverage areas of a macro cell base station and a small cell base station using different frequency bands overlap, includes a storage unit and a control unit. The storage unit stores small cell base station information indicating whether the small cell base station is present within a coverage area of a macro cell base station. The control unit instructs a radio terminal apparatus present within the coverage area of the macro cell base station to perform quality measurement in a frequency band of the small cell base station when the small cell base station is present within the coverage area of the macro cell base station based on the small cell base station information.

Communication control apparatus, radio base station apparatus, radio terminal apparatus, and communication control method

A wireless communication system includes an upper transmission station and a lower transmission station, each serving as a transmission station, a terminal serving as a reception station. The upper transmission station allocates a downlink control channel for each terminal to part of a predetermined data-channel region ascribed to the lower transmission station based on a demodulation reference signal for each transmission station. Based on the allocation result, the lower transmission station allocates the downlink control channel for each terminal, which is disposed at art of the data-channel region thereof. The terminal decodes the downlink control channel based on the demodulation reference signal.

Wireless communication system, terminal, transmission station, and wireless communication program

Provided is a base station apparatus that employs a dynamic scheduler mode which performs wireless resource allocation for each subframe and applies a result of the allocation to the corresponding subframe, or a continuous transmission scheduler mode which performs wireless resource allocation for each subframe appearing periodically based on a period P and applies a result of the allocation for the relevant subframe to P continuous subframes from a subframe n to a subframe n+P&#x2212;1. The base station apparatus includes a terminal communication device that communicates continuous transmission application ON/OFF information, which indicates whether or not the continuous transmission scheduler mode is employed, and continuous transmission period information, which indicates a period of continuous transmission scheduling according to the continuous transmission scheduler mode, to a terminal. The terminal communication device may store the continuous transmission application ON/OFF information and the continuous transmission period information in a PDCCH region.

Base station apparatus and communication terminal

A reference signal transmission scheduling device, which performs scheduling on uplink transmission of a reference signal (SRS) from a mobile terminal to a base station in a wireless communication system, is designed to appropriately allocate an SRS transmission resource to the mobile terminal in consideration of the current circumstances of the mobile terminal. Herein, the maximum value of an SRS bandwidth is calculated based on the maximum transmission-enabled power of the mobile terminal, while the minimum value of the SRS bandwidth is calculated based on the mobility of the mobile terminal. Additionally, the SRS bandwidth, which is actually used by the mobile terminal subjected to SRS transmission resource allocation, is determined within the range between the maximum value and the minimum value of the SRS bandwidth.

Reference signal transmission scheduling device and reference signal transmission scheduling method

A base station apparatus in a wireless communication network system includes an information obtaining unit that obtains a delay request value for application data which is transmitted and received between a terminal and a communication partner thereof through an application layer, where the terminal performs data transmission and reception by wirelessly accessing the base station apparatus; and a resource allocator that computes, based on the delay request value for the application data, a residual time up to a time by which an application data transmitting side, which is one of the base station apparatus and the terminal, should complete wireless transmission of TCP packets which store the application data, and performs allocation of a wireless resource used in wireless communication between the base station apparatus and the terminal, based on a degree of margin of the residual time for a prearranged transmission time of the wireless transmission from the application data transmitting side.

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Fujimino, Japan

Xiaoqiu Wang