Abstract: A distributed scheduling method in a Device-to-Device (D2D) communication system is provided. The method includes transmitting, to a peer device, first resource information including a link identifier and start position information of resources to be allocated, receiving, from the peer device, second resource information in which at least one of the resource start position information and a resource allocation amount is adjusted based on the first resource information, and determining the resource start position based on the first resource information and second resource information.

Abstract: A method and an apparatus for synchronization for Device-to-Device (D2D) communication in unlicensed frequency bands are provided. The method includes determining whether a signal is detected during a preset time period within a synchronization period, after transmitting a synchronization signal during the synchronization period for the D2D communication, when it is determined that the D2D communication is to be performed, and starting the time period for the D2D communication and performing the D2D communication during the time period for the D2D communication, when it is determined that the signal is not detected.

Abstract: A communication method of a device to device (D2D) user equipment (UE) in a cellular system supporting a communication frame structure including one or more subframes used for a communication of the D2D UE is provided. The method includes reading an alarm region located within a first subframe, wherein the alarm region indicates whether a communication signal having a priority is included in the first subframe or a second subframe related to the first subframe, and transmitting the communication signal through one of the second subframe and a third subframe related to the second subframe, based on information read from the alarm region.

Abstract: The present invention provides a method for providing a service to a device having an interest in a specific service in a device-to-device (D2D) condition. The method includes: searching for a device which enters into an area managed by a device which provides the specific service; and identifying an interest of the searched device in the specific service and inviting the searched device to participate in the specific service. In the method, by selectively connecting a session based on a service interest, an efficient management in view of an entire network capacity is possible and an advantage of reducing a time for session connection is achieved.

Abstract: Disclosed is a control method of a communication system including at least one sensor that a user wears, a wireless communication apparatus and a coordinator.

Abstract: A device and a method for performing Device to Device (D2D) communication in a wireless communication system are provided. The method includes transmitting information on a self-frequency band selected from all frequency bands for the D2D communication, to the second mobile station, receiving information on a counterpart-frequency band selected for the D2D communication, from the second mobile station, determining transmission and reception frequency bands to be used for the D2D communication, based on the information on the self-frequency band and the information on the counterpart-frequency band, transmitting data to the second mobile station in the determined transmission frequency band, and receiving data from the second mobile station in the determined reception frequency band.

Abstract: A method for supporting an application by Device to Device (D2D) communication in a wireless network includes acquiring range control information from an application upon selection of the application installed in the source device, controlling transmission power of a discovery signal for discovering a target device to conduct D2D communication, based on range control information defined for the selected application, and transmitting the discovery signal with the controlled transmission power. An apparatus includes a controller configured to acquire range control information from an application upon selection of the application installed in the source device, and control transmission power of a discovery signal for discovering a target device to conduct D2D communication, for the selected application based on range control information defined for the selected application, and a transmitter configured to transmit the discovery signal with the controlled transmission power.

Abstract: The present invention relates to a position compensation device using visible light communication and a method thereof. To this end, the present invention receives a visible light signal which includes lighting position information from a lighting device to extract the lighting position information from the received visible light signal, and calculates a compensated position of a position compensation device by using the extracted lighting position information if a request for position compensation exists, thereby providing an exact position of a user indoors.

Abstract: A method for operating a device in a wireless communication system supporting Device to Device (D2D) communication system includes receiving a reference signal from each of at least one transmitting device, estimating a frequency offset between the reference signals and a comparison reference signal corresponding to the reference signals, and adjusting a transmit frequency of a voltage controlled oscillator of the device using the estimated frequency offset estimation. An apparatus for compensating for a frequency offset of a device in a wireless communication system supporting Device to Device (D2D) communication system includes a frequency offset estimator configured to receive reference signals from each of at least one transmitting device, and estimating a frequency offset between the reference signals and a comparison reference signal corresponding to the reference signals, and a voltage controlled oscillator configured to adjust a transmit frequency using the estimated frequency offset.

Abstract: A link scheduling method in a system for performing Device-to-Device (D2D) communication includes periodically collecting information indicating whether to perform a medium access from at least one neighboring link determining at least one link expected to perform a medium access in a corresponding traffic slot among links with a higher priority than the terminal based on the collected information, and determining whether to perform the medium access of the terminal by considering only the at least one link expected to perform the medium access.

Abstract: An apparatus and a method for providing a call taxi service based on D2D communication are provided. When a user terminal executes a call taxi service, a call taxi service request is transferred to a terminal from at least one taxi located in a neighboring area of the user terminal, and then the user terminal directly selects one taxi or one taxi is selected through a competition between taxis. As a result, a process of providing the call to the selected taxi. Accordingly, the user has an advantage of using a quick call taxi service without going through a separate call center.

Abstract: A method and apparatus for performing initial entry for Device-to-Device (D2D) communication in a wireless communication system include transmitting an initial entry request including a service request for D2D communication to a Mobility Management Entity (MME) by a terminal, and if the service request for D2D communication is accepted, receiving information indicating that the initial entry request is accepted, including D2D communication information from the MME by the terminal.

Abstract: An apparatus and method for maintaining backward compatibility with a narrow-band wireless communication system in a wide-band wireless communication system is provided. The base station comprises a scheduler, a control information generator, a resource mapping unit and a transmitter. The terminal comprises a resource allocation information checking unit, a receiver and a transmitter.

Abstract: A data center is electrically coupled to a power grid at two separate access points, which may be located within geographic proximity to each other. Each access point is located between two power generation systems. The access points have one or more power generation systems located between them, allowing the data center to be coupled to three or more power generation systems simultaneously and have access to power in the event of multiple power generation system failure. The data center may comprise two separate data center power inputs, which may each be connected to a separate power grid access point. The power grid may provide a high voltage level to the data center, and the data center may comprise transformers which step the voltage down to a lower voltage level. The data center may comprise one such transformer coupled to each of the two data center power inputs. The outputs of such transformers may be coupled together.

Abstract: In order to generate multiple-access signals, each transmitter transmits information by using all or a part of channel resources. The signal of each transmitter is mapped to an OFDM time-frequency resource space as a trellis modulation path. A mobile communication system maps trellis modulation paths of a plurality of transmitters to the same resource space. In order to effectively detect and distinguish signals of a plurality of transmitters transmitted through the same channel resource space, a receiver uses a message passing method between symbols and a path connection method. The receiver uses a state space expansion method, a backward pre-decoding method, and a successive interference cancellation method to more efficiently reconstruct a discovery signal.

Abstract: The need for an uninterrupted power supply (UPS) in a data center is obviated by tying a DC voltage from a backup power source directly to the motherboards of multiple servers in the data center. AC power received from a power utility service is converted into a lower voltage by a site transformer and then provided to one or more power distribution units at a site. The power distribution units supply power to a plurality of servers, which include power supplies that convert the AC electrical power to DC electrical power for use by the servers' motherboards. In the event of a failure of power from the utility service, the backup power source provides DC electrical power to the motherboards, e.g., for sufficient time to start up a generator to provide power in place of the utility service.

Abstract: A method and an apparatus for synchronization for a device-to-device communication are disclosed. The method includes: instantly adjusting a synchronization phase value according to a time point when a synchronization signal is received, as soon as a device receives the synchronization signal from an adjacent device in an unconnected state; accumulatively storing at least one phase adjustment value according to a time point when at least one synchronization signal is received, whenever the device receives the at least one synchronization signal from at least one adjacent device in a connected state; and adjusting the synchronization phase value according to the stored at least one phase adjustment value when the device transitions from the connected state to the unconnected state.

Abstract: A method and a system for operating a Mutual Broadcast Period (MBP) and Contention Access Period (CAP) for load control are provided. The proposed system and method is suitable for a short-range communication environment such as communication environment in or around the human body, and is for a mesh network communication environment in which one piconet is formed around the human body or a plurality of devices are connected. When signals carrying biometric information are periodically received from a plurality of sensor devices for medical purposes, the system and method may achieve efficient resource access by performing load control in a distributed manner, contributing to a reduction in access delay and power consumption and enabling appropriate QoS control.

Abstract: Disclosed is a method of controlling a communication system including one or more sensors attached to a user, a wireless communication apparatus, and a coordinator.

Abstract: A method is provided for performing handoff in a communication system including a serving base station (BS) in communication with a mobile station (MS), at least one neighbor BS using a communication scheme different from a communication scheme of the serving BS, and the MS capable of communicating with the neighbor BS. The method includes compensating a signal strength of one of the serving BS and the neighbor BS, received at the MS, such that handoff decision is possible, and determining whether to perform a handoff of the MS, using the compensated signal strengths.