Abstract: Provided is a method, and an apparatus and communication system to perform the method, of detecting a victim terminal and performing an interference coordination in a multi-cell environment. The multi-cell environment may include a heterogeneous cell environment including a small cell and a macro cell. The method includes determining whether a macro terminal is located within a cell coverage of a small base station, and adjusting the cell coverage according to the determination.

Abstract: Provided are a base station and a plurality of member nodes for transmitting and receiving network coding based multicast traffic. The base station may transmit multicast traffic, and the member node may transmit an acknowledgement (ACK) signal based on received multicast traffic. A determination made be made as to whether the multicast traffic is to be retransmitted, based on a number of member nodes transmitting ACK signals.

Abstract: Provided is a communication method and a data frame for a communication system having a relay station. An uplink sub-frame of the data frame may include a first uplink relay sub-frame which corresponds to a time frame where relay stations selected among a plurality of relay stations simultaneously transmit uplink relay signals to a base station, and a second uplink relay sub-frame which corresponds to a time frame where the remaining relay stations transmit remaining uplink relay signals to the base station using a scheduled radio resource. A downlink sub-frame of the data frame may include a first downlink relay sub-frame which corresponds to a time frame where a base station simultaneously transmits downlink relay signals to relay stations selected from among a plurality of relay stations, and a second downlink relay sub-frame which corresponds to a time frame where the base station transmits remaining downlink relay signals to the remaining relay stations using a scheduled radio resource.

Abstract: A technology that can adaptively control an access mode according to a shared band or an unlicensed band used by an adjacent communication system. An access mode controlling apparatus includes a band recognition unit to recognize a usage rate of an unlicensed band or a shared band that is used by an adjacent communication system of a target communication system; a mode determination unit to determine, as an access mode, any one of a contention access mode and a contention-free access mode, based on the usage rate of the unlicensed band or the shared band; and an information transmitter to transmit mode information associated with the determined access mode to member nodes or a base station of the target communication system.

Abstract: Communication methods of a macro base station which collects position information about a mobile micro base station and that is served by the macro base station, predicts a channel between the macro base station and the micro base station, and performs a handover between the macro base station and the micro base station based on a state of the predicted channel is provided.

Abstract: A link adaptation system using a Doppler frequency is provided. The link adaptation system includes: a Doppler frequency estimation unit to estimate a Doppler frequency of a signal transmitted via a wireless channel; a Signal to Noise Ratio (SNR) measurement interval determination unit to determine an SNR measurement interval of the signal transmitted via the wireless channel based on the estimated Doppler frequency; and an SNR measurement unit to measure an SNR of the signal based on the determined SNR measurement interval.

Abstract: Provided is a communication method of a vehicular access point, a vehicular user equipment, and a macro base station for a user present in a vehicle capable of effectively forming an operational relationship between the vehicular access point and the macro base station using a plurality of operational modes. The plurality of operational modes may be differentiated based on an operation of the vehicular access point and the macro base station, and are capable of transitioning the vehicular access point from an active state to an idle state by a triggering with respect to the vehicular access point.

Abstract: The present invention relates to a power saving in a wireless local area network including a plurality of access points providing at least one mobile station in each access point cell boundary with access service, the mobile station transits between an active mode and an idle mode. The power saving method includes grouping the access points into at least one paging group with a paging group boundary; determining if the a mobile station is in the idle mode in which the mobile station switches between an awake state and a doze state every predetermined time interval, or the active mode in which the mobile station is in the awake mode; and if the mobile station is in the idle mode enabling an idle handoff which occurs only when the mobile station crosses the paging group boundary. In the present invention, the handoff occurs when the mobile terminal crosses the paging group boundary but not the access point cell in the idle mode, resulting in reduction of power consumption.

Abstract: A method of transmitting secret information in a transmitting end and a method of receiving secret information at a receiving end, based on multi-input multi-output (MIMO) multiplexing using antennas, are provided. The method of transmitting includes selecting one or more indices of the secret information that correspond to at least one receiving antenna among receiving antennas, and mapping the one or more indices to an information vector. The method of transmitting further includes precoding the information vector based on channel information between transmitting antennas and the receiving antennas, and beamforming the precoded information vector, using the transmitting antennas.

Abstract: A method of secure communication in a transmitter, includes determining a method of generating a training sequence that is shared with a receiver. The method further includes generating the training sequence based on the method of generating the training sequence, and secret information. The method further includes communicating with the receiver based on channel information derived from the training sequence.

Abstract: A communication method of a macro base station including reporting information about a broadcast channel section in order to identify a femtocell in a macrocell of the macro base station set in a downlink broadcast channel of the macrocell, is provided. The macro base station receives position information of a mobile terminal and a request for information about neighboring femto base stations from the mobile terminal, when the mobile terminal identifies an accessible femto base station among the at least one femto base station in the broadcast channel section. The macro base station generates a list of the neighboring femto base stations of the mobile terminal and information about the neighboring femto base stations based on the position information of the mobile terminal, and transmits the list of the neighboring femto base stations and the information about the neighboring femto base stations to the mobile terminal.

Abstract: A method and apparatus of controlling resources of a femto base station for protecting a macro terminal and controlling interference among femto base stations are provided. The femto base station or a gateway of the femto base station may allocate resource blocks of a femto cell based on a silencing resource block for protecting the macro terminal. Also, the femto base station or the gateway of the femto base station may allocate the resource block of the femto cell based on a relative location between the macro base station and the femto base station and a victim macro terminal. The femto base station or the gateway of the femto base station may allocate the resource block of the femto cell based on a resource block used by a neighboring femto base station.

Abstract: Described herein is a method of sharing a frequency resource between a plurality of transmission/reception pairs in a communication system. Also described is an inner-cell coordinator included in the communication system that may be used to carry out the method of sharing a frequency resource between a plurality of transmission/reception pairs.

Abstract: Communication methods of a macro base station which collects position information about a mobile micro base station and that is served by the macro base station, predicts a channel between the macro base station and the micro base station, and performs a handover between the macro base station and the micro base station based on a state of the predicted channel is provided.

Abstract: A multi-band scheduling method determines frequency bands for each of a plurality of frames existing in a single session queue from among a plurality of frequency bands based on data characteristics of each of the plurality of frames. In particular, the multi-band scheduling method may assign a frame with a high significance to a frequency band having a superior channel state, thereby increasing communication reliability. Also, a broadcasting service system may use the multi-band scheduling method to effectively provide the broadcasting services.

Abstract: An apparatus for storing handover information in a mobile communication system is provided. The apparatus includes an estimation unit configured to estimate a direction of arrival (DOA) of a received signal with respect to a first base station based on the received signal, the received signal being received from a terminal belonging to the first base station, and a storage unit to store the estimated DOA as handover information associated with a second base station when the terminal is handed over to the second base station.

Abstract: A communication method of a macro base station including reporting information about a broadcast channel section in order to identify a femtocell in the macrocell, is provided. The macro base station receives position information of a mobile terminal and a request for information about neighboring femto base stations from the mobile terminal, when the mobile terminal identifies an accessible femto base station in the broadcast channel section. The macro base station generates a list of the neighboring femto base stations and information about the neighboring femto base stations based on the position information of the mobile terminal, and transmits the list and the information about the neighboring femto base stations to the mobile terminal.

Abstract: A communication system performing a coordinated multipoint transmission is provided. A mobile station may measure expected channel quality information when an interference of a serving base station does not exist. The serving base station may determine whether a neighbor base station and the serving base station are eligible to perform the coordinated multipoint transmission. The serving base station may determine whether the neighbor base station and the serving base station are eligible to perform the coordinated multipoint transmission using a criterion associated with an evaluation of an increase in a transmission rate of the mobile station.

Abstract: A terminal receives a unique sequence from each of at least two base stations, and transmits a mixture of quantized unique sequences to a serving base station. The serving base station extracts components respectively corresponding to base stations from the mixture of the quantized unique sequences, and estimates a location of a terminal based on the extracted components. The serving base station may calculate a received signal strength or a delay for each of the unique sequences received by the terminal, based on the extracted components, and estimate the location of the terminal based on the received signal strength or the delay. In addition, the terminal may estimate its own location by performing an algorithm used by the serving base station.

Abstract: Provided is a method and apparatus for determining a downlink beamforming vector in a hierarchical cell communication system. Small base stations may determine transmit beamforming vectors of the small base stations so that interference from the small base stations may be reduced in a macro terminal. A macro terminal and small terminals may determine receive beamforming vectors based on the transmit beamforming vectors of the small base stations. A macro base station may determine a transmit beamforming vector based on effective channels to terminals using the receive beamforming vectors of the terminals.