Kddi Corporation

Kddi Research, Inc.

University of Southern California

Takeo Ohseki

Yasuhiro Suegara

Issei Kanno

Satoshi Konishi

Kosuke Yamazaki

Masahito Umehara

Toshiaki Yamamoto

Toshihiko Komine

Yosuke Akimoto

Hiroyasu Ishikawa

Hideyuki Shinonaga

Xiaoqiu Wang

Hailan Peng

Kazuya Moriwaki

Masaya Shibayama

Masaaki Ito

Andreas F Molisch

Hiroki Takeda

Takashi Inoue

Yanwei Li

Yoshio Kunisawa

Kyesan Lee

Masato Furudate

Yoshitaka Takaku

Kazuhide Toda

Shunsuke Kamiwatari

Naoto Tsumachi

Jungyeon Hong

A base station apparatus performs, for a currently connected terminal apparatus, setting of a radio resource control (RRC) layer for another base station apparatus that is a destination candidate for a handover by the terminal apparatus from the base station apparatus, instructs the terminal apparatus to transmit a random access preamble to the other base station apparatus via a physical downlink control channel (PDCCH) order without handover to the other base station apparatus being performed, and transmits, to the terminal apparatus, a command instructing for handover to the other base station apparatus in response to the terminal apparatus being in a state for handover to the other base station apparatus.

Terminal apparatus, and control method for performing handover having enhanced communication efficiency

A communication device capable of connecting to and communicating with another device using a first function operating as a terminal device and a second function operating as a base station device, the communication device acquires a first reception power density of a signal of a downlink received from an upstream device connected by the first function, acquires a second reception power density of a signal of an uplink received from a downstream device connected by the second function, and transmits a transmission power control command for controlling transmission power of the signal of the downlink to the upstream device, based on the first reception power density and the second reception power density.

Communication device, control method and computer-readable storage medium for executing transmission power control in relay transmission

A terminal device that comprises a plurality of antennas notifies a network to which the terminal device belongs of information according to which it is possible to specify at least one of, among the plurality of antennas, a second antenna having a predetermined characteristic in common with a first antenna included in the plurality of antennas, and a third antenna not having the predetermined characteristic in common with the first antenna.

Terminal device, network node, and control method for communication control with consideration given to antenna arrangement

A terminal comprises a function capable of operating in a plurality of states that include a first state in which a connection with a base station has been established, and a second state in which a connection with a base station has not been established, but the base station holds information regarding the terminal device. After starting operation in the second state from a state in which the terminal operates with a first base station in the first state, if predetermined information that enables communication with the first base station in the second state and that has been acquired from the first base station in the first state is held, the terminal determines whether a signal transmission target has changed from the first base station to a second base station device, and performs communication according to a result of the determination.

Enabling a terminal device to perform efficient communication in a stand-by state

A terminal device selects, in a case where data that is to be transmitted to the base station device is generated, one setting for use in transmission of a scheduling request to a base station device, from among a plurality of settings that correspond to different combinations of a bandwidth, a time duration, and a periodicity and can be used in transmission of the scheduling request, and transmits the scheduling request to the base station device with use of the one setting that was selected.

Terminal device, base station device, control method, and storage medium for controlling the transmission of signals

A control apparatus that is connected to a plurality of antennas and performs communication of user data with a terminal apparatus using at least one of the plurality of antennas, specifies a reception state of a random access preamble transmitted from the terminal apparatus for establishing connection with the control apparatus, at each of the plurality of antennas, selects an antenna to be used when performing communication of user data with the terminal apparatus, from the plurality of antennas based on the respective reception states at the plurality of antennas, and performs control such that communication of user data is performed with the terminal apparatus using the selected antenna.

Control apparatus selectively using plurality of antennas, control method, and computer-readable storage medium

A control apparatus may wirelessly communicate with a terminal apparatus. When a random access preamble is received from the terminal apparatus, if the random access preamble is not based on a setting notified by the control apparatus, the control apparatus may scramble communication with the terminal apparatus after the random access preamble is received, using a scrambling sequence that is based on second identification information different from first identification information corresponding to the control apparatus.

Control apparatus selectively using plurality of antennas, terminal apparatus communicating with control apparatus, and communication method

A terminal apparatus transmits a predetermined message to a base station apparatus based on a two-step random access procedure, upon receiving one signal that is transmitted from the base station apparatus in response to the predetermined message, and includes pieces of upper layer control information for the terminal apparatus and another terminal apparatus in a multiplexed manner, specifies a first radio resource for transmitting a first response signal indicating whether or not succeeded in receiving control information that is for the terminal apparatus and is included in the one signal, and is different from a second radio resource for transmitting a second response signal for the other terminal apparatus, based on at least one of a control signal that is used for transmitting the one signal and the one signal, and transmits the first response signal using the first radio resource.

Terminal apparatus for executing two-step random access procedure, base station apparatus, and control method

The present invention provides a terminal device comprising: transmission unit configured to transmit a first message including user data to a base station device in a random access procedure in a mobile communication network; and control unit configured to control the transmission unit to: in a case where a predetermined condition to transition from an inactive state to a connected state is satisfied, transmit the first message that includes predetermined information for notifying the base station device that the terminal device needs to transition to the connected state; and in a case where the predetermined condition is not satisfied, transmit the first message that does not include the predetermined information.

Terminal device executing random access procedure, base station device, control method, and computer-readable storage medium

A terminal apparatus, which executes a two-step random access procedure or a four-step random access procedure to establish a connection with a base station apparatus, executes control such that, in a case where a first message of the two-step random access procedure including a preamble and predetermined information for connection establishment is transmitted and a number of unsuccessful attempts to receive the first message by the base station apparatus exceeds a predetermined number, the terminal apparatus transmits a second message to be transmitted from the terminal apparatus to the base station apparatus in the four-step random access procedure.

Terminal apparatus, base station apparatus, control method, and computer-readable storage medium for executing random access procedure

Terminal device that performs communication in stand-by state, method for controlling the same, and computer-readable storage medium

There is provided a base station apparatus capable of transmitting a signal to a terminal apparatus and receiving an acknowledgement from the terminal apparatus. The base station apparatus transmits, to the terminal apparatus, information pertaining to a resource to be used to transmit the acknowledgement and determined in accordance with a length of a period from when the signal is transmitted to the terminal apparatus until the acknowledgement is received, and receives the acknowledgement transmitted by the terminal apparatus using the resource by specifying the resource based on the information.

Base station apparatus, terminal apparatus, communication method, and computer-readable storage medium

A communication apparatus, which is capable of performing, in a predetermined frequency band to be used by a first radio communication system configured to periodically transmit a reference signal with a predetermined frequency spacing, communication using a second radio communication system that is different from the first radio communication system, performs communication of the second radio communication system while the base station apparatus of the first radio communication system operates in a mode in which periodic transmission of the reference signal is stopped for a predetermined period, based on information relating to a timing at which a base station apparatus of the first radio communication system is to operate in the mode.

Communication apparatus, communication method, and computer-readable storage medium for implementing coexistence with legacy system

A communication device, which is capable of performing communication via a second wireless communication system that is different from a first wireless communication system, in a frequency band that is used by the first wireless communication system, the first wireless communication system periodically transmitting a reference signal, transmits, to a base station device of the first wireless communication system, information for operating the base station device in a mode in which the periodical transmission of the reference signal is interrupted for a predetermined period, and performs communication involving a predetermined signal of the second wireless communication system while the base station device of the first wireless communication system is operating in the mode.

Communication device, communication method, and storage medium for implementing coexistence with legacy system

A terminal apparatus, which is able to establish a connection with a base station apparatus via a two-step random access procedure by transmitting a first signal including a random access preamble and predetermined information to the base station apparatus and receiving a second signal as a reply to the first signal from the base station apparatus, acquires a random access-radio network temporary identifier (RA-RNTI) on the basis of a radio resource having been used to transmit the predetermined information with the first signal, and executes reception processing of the second signal using the RA-RNTI.

Growing community of inventors

Fujimino, Japan

Takeo Ohseki