Electronics and Telecommunications Research Institute

JaeSheung Shin

Pyeong Jung Song

Sung-Min Oh

Jae Heung Kim

Ji Hyung Kim

Changhee Lee

Jung-Im Kim

Hyun Seo Park

Yeong Jin Kim

Ae-Soon Park

Yeon Seung Shin

Kyung Sook Kim

Choongil Yeh

Ok-Sun Park

Gyung-chul Shin

Hyun-Yong Hwang

SoonGi Park

Eunah Kim

Taesoo Kwon

Sook Yang Kang

A method and an apparatus for transmitting data in communication between terminals are provided. A terminal disposes at least one first reference signal configured based on a first parameter. The terminal disposes at least one second reference signal configured based on a second parameter, in addition to the first reference signal configured based on a first parameter. Data of a first structure in which the first reference signal is included or data of a second structure in which the first reference signal and the second reference signal are included is transmitted.

Method and apparatus for transmitting data in direct device-to-device communication

A base station determines whether a reception of each uplink signal transmitted by a plurality of terminals succeeds. The base station generates a response bit map representing whether the reception succeeds. Further, the base station transmits first downlink control information (DCI) including the response bit map to the plurality of terminals through a first downlink control channel.

Method and apparatus for transmitting downlink response to uplink transmission, and method and apparatus for transmitting synchronization signal

A base station infers a random access failure rate depending on a random access collision of terminals performing random access and controls a random access opportunity of a terminal that fails the random access by using the random access failure rate of each terminal. Also, information for the controlled random access opportunity is transmitted to the terminal that fails the random access.

Method and apparatus for controlling random access opportunity in mobile communication system

A UE does not immediately perform handover after receiving a handover command from a serving base station, but instead backups that message and continuously compares the signal strength of a serving base station and the signal strength of a target base station and performs a handover to the target base station at the best timing when handover is required. Once the timing of handover is determined, the UE transmits a handover indication message to the serving base station, and thereafter the UE performs a handover to the target base station.

Handover method and apparatus

When transmitting a user message, in a call setting period of a base station and a terminal and a radio connection state between a base station and a terminal, whenever a data transmittable channel resource is available, user messages of an amount corresponding to the available channel resource are transmitted. Therefore, user messages can be divided and transmitted according to an available channel in a call setting period.

Method of transmitting user message, terminal and base station using the method

When a terminal moves from a serving cell to a target cell, the carrier in use is switched to the primary carrier of the serving cell and then handed over to the target cell. Hereupon, handover is performed by switching the carrier used by the terminal operating with the primary carrier of the serving cell to the primary carrier of the target cell to perform handover. When the terminal has fully entered the target cell, the best carrier is selected from among the carriers available to the target cell, thus allowing the terminal to perform frequency conversion to the best carrier.

Method for handover in multi-carrier system

Growing community of inventors

Daejeon, South Korea

JaeSheung Shin