Abstract: A method of controlling femtocell interference considering a macrocell is provided. The method of controlling the interference includes a method of setting transmission power of the femtocell and methods of avoiding the interference of the femtocell. The methods of avoiding the interference include a PRB rotation method, a PRB transmission power restriction method, a hybrid method and a UB rotation method. The method of setting the transmission power and the methods of avoiding the interference may be implemented independently or implemented in combination with each other. Hence, according to the present invention, the femtocell itself can control the interference without affecting an interface of an existing macrocell base station and without signaling through the interface with the macrocell.

Abstract: A cell search method for a terminal capable of cell search control includes: receiving a message including first cell search information from a macro cell base station that manages a macro cell; updating second cell search information stored in the terminal based on the first cell search information; and searching for an accessible cell based on the updated second cell search information.

Abstract: An MBMS providing apparatus and an MBMS providing method using the same in a cloud radio access network are provided. The MBMS providing apparatus includes a third layer into which a plurality of network layers providing an MBMS are integrated in the plurality of DUs, and a second layer into which a plurality of datalink layers providing the MBMS are integrated in the DUs. Therefore, the present invention integrates the layers that provide the MBMS in the plurality of DUs, and provide the MBMS by MBSFN synchronization area through the integrated layers. Accordingly, by performing the MBMS by MBSFN synchronization area through respective integrated layers, the present invention can prevent the occurrence of an unnecessary load, thus enhancing the performance of a communication network.

Abstract: A method of selecting a plurality of cells and a method of distributed-transmitting data to enhance mobile data transmission rate in a wireless overlay network are disclosed. A cell selection method which selects a cell for distributed-transmission of data in a wireless overlay network of a plurality of cells may include receiving, by a base station, a request for distributed data transmission from a mobile terminal, and selecting a plurality of wireless communication devices for distributed-transmission of data to the mobile terminal among adjacent wireless communication devices to the mobile terminal based on received signal strength (RSS) information on the mobile terminal with respect to the adjacent wireless communication devices, available resource information on the adjacent wireless communication devices and a service profile of the mobile terminal.

Abstract: 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.

Abstract: 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.

Abstract: A base station, a user equipment, and a method for operating a cooperative multipoint (CoMP) transmitter and receiver (Tx/Rx) are disclosed. The operating method includes receiving, from a peripheral cell, precoding matrix index (PMI) information to be used by a user equipment of the peripheral cell, and transmitting the received PMI information to target user equipments allocated with an entire frequency range, among a plurality of user equipments present in a current cell.

Abstract: A technology for inter-cell interference control is provided. In one general aspect, the inter-cell interference may be controlled by resource allocation scheduling or power management. A cell may be divided into a plurality of regions. A constant available resource band and a selectively available band are allocated to each region. Each of the allocated resource bands is assigned with an interference characteristic. The resource allocation scheduling and the power management are performed according to the resources allocated to the respective regions and the interference characteristics assigned to the respective resources.

Abstract: Disclosed is a mobility management method for use in a cellular mobile communication system. The mobility management method is configured to save radio resources and provide a stable service by detecting a cell in which a dwell time of user equipment (UE) is short as an island cell and performing a direct handover (HO) to an appropriate cell without handing over the UE to the island cell. There are provided three methods including a base station-based method, a UE measurement-based method, and a UE history-based method according to how to measure a dwell time in which the UE stays in a cell, a component in which obtained information is received within a network, and how to process an HO using the information.

Abstract: Provided is a subframe scheduling method in which a relay may transmit interval information of a service to a base station, and the base station may modify a location of a subframe based on the interval information, and thereby preventing a quality deterioration occurring due to a retransmission failure. The subframe scheduling method may include: setting and transmitting, by a base station, subframe information; setting and implementing, by a relay, a service based on the subframe information; transmitting, by the relay, interval information of the service to the base station; modifying, by the base station, the subframe information based on the interval information; and transmitting, by the base station, the modified subframe information to the relay.

Abstract: Disclosed are an apparatus and a method for managing radio resources, capable of effectively managing radio resources. When a normal call and a handover call are attempted, radio resources are allocated and it is determined whether or not to perform an overload control based on received load related information and then it is determined whether or not to admit the call depending on an availability of a bandwidth for radio resources, a priority of real time traffic or a locking probability of data. The quality and efficiency of a mobile communication service is enhanced by pertaining an effective allocation on radio resources and controlling the load of radio resources in the mobile communication system. The radio resource managing apparatus and method using the same are applied to IMT (International Mobile Telecommunications)-Advanced system base station, thereby optimizing the efficiency of radio resources.

Abstract: There are provided a control channel managing apparatus of a base station, a control channel searching apparatus of a user equipment (UE) and a control channel allocating method in a mobile communication system. When an aggregation level is high and a plurality of UEs having the same starting address of a control channel search space are scheduled in a corresponding subframe, control information with respect to conflicting UEs which have lower priorities in terms of allocation of control information can be transmitted through the conflicting UE space. Hence, more control information can be transmitted and the number of available UEs corresponding to the control information increases, and thus an improvement in the performance of the entire network can be achieved.

Abstract: Provided are a physical downlink control channel (PDCCH)-based scheduling method and apparatus suitable for use by a base station in a long-term evolution (LTE) system. The scheduling method includes: determining an aggregation level of a common search space of a PDCCH by considering channel quality of a plurality of user equipments (UEs); identifying the number of PDCCH candidates and the number of messages, which require allocation of the common search space, based on the determined aggregation level and selecting messages by a smaller number of the number of messages and the number of PDCCH candidates; and allocating PDCCH resources and physical downlink shared channel (PDSCH) resources for the selected messages. In a situation where the PDCCH resources are shared by downlink scheduling information and uplink scheduling information of different UEs, the PDCCH resource-based scheduling method can be used by the base station to efficiently utilize the PDCCH resources.

Abstract: Disclosed is a mobility management method for use in a cellular mobile communication system. The mobility management method is configured to save radio resources and provide a stable service by detecting a cell in which a dwell time of user equipment (UE) is short as an island cell and performing a direct handover (HO) to an appropriate cell without handing over the UE to the island cell. There are provided three methods including a base station-based method, a UE measurement-based method, and a UE history-based method according to how to measure a dwell time in which the UE stays in a cell, a component in which obtained information is received within a network, and how to process an HO using the information.

Abstract: Disclosed is a method of controlling transmission power of femtocells for interference control. The method includes (a) setting transmission power of femtocells to initial transmission power, (b) establishing inequalities between received signal to interference ratios (SIRs) of I user terminals and SIRs satisfying service requirements of the terminals as I simultaneous inequalities, (c) identifying whether the inequalities constituting the simultaneous inequalities are satisfied, and (d) maintaining currently adjusted transmission power and stopping transmission power adjustment of the femtocells if all the inequalities are satisfied in operation (c), wherein operations (c) and (d) are iterated while inequalities are sequentially selected one by one from at least some inequalities if at least some inequalities are not satisfied in operation (c) and transmission power is adjusted one by one in terms representing the transmission power of femtocells in the inequalities.

Abstract: A method of controlling femtocell interference considering a macrocell is provided. The method of controlling the interference includes a method of setting transmission power of the femtocell and methods of avoiding the interference of the femtocell. The methods of avoiding the interference include a PRB rotation method, a PRB transmission power restriction method, a hybrid method and a UB rotation method. The method of setting the transmission power and the methods of avoiding the interference may be implemented independently or implemented in combination with each other. Hence, according to the present invention, the femtocell itself can control the interference without affecting an interface of an existing macrocell base station and without signaling through the interface with the macrocell.

Abstract: A method and apparatus for controlling interference between cells for non-real time data transfer in a mobile communication network is provided. The method of controlling interference between cells in a mobile communication system including a plurality of cells includes: dividing each cell into at least one segment based on density of terminals within each cell and distance from the center of each cell; allocating rise over thermal (RoT) with respect to each segment based on the distance from the center of each cell, an attenuation ratio according to the distance, and a shadowing factor; and providing data services to terminals within each segment according to the allocated RoT. Accordingly, it is possible to improve system throughput.

Abstract: A base station, a user equipment, and a method for operating a cooperative multipoint (CoMP) transmitter and receiver (Tx/Rx) are disclosed. The operating method includes receiving, from a peripheral cell, precoding matrix index (PMI) information to be used by a user equipment of the peripheral cell, and transmitting the received PMI information to target user equipments allocated with an entire frequency range, among a plurality of user equipments present in a current cell.

Abstract: Provided is a method for managing a cross-layer handover. The method includes the steps of: managing a predetermined number of neighbor cells as a handover candidate set based on signal strength and route estimation; transmitting a Measurement Report message having the handover candidate set information to a source base station according to a reporting event; and performing a handover according to a Handover Command message received from the source base station.

Abstract: The present invention relates to a vertical handoff method. According to the present invention, a serving network of a mobile station is determined. Herein, the mobile station that can access a first network having relatively wide service coverage and a second network having relatively narrow service coverage in an area where service coverages of heterogeneous networks are overlapped. When accessing the serving network of the first network, it is determined whether a received signal strength received from the second network is greater than a first threshold value. In addition, a first vertical handoff is decided by using a result of prediction of a transition pattern of the received signal strength that is greater than the first threshold value. When the serving network is the second network, it is determined whether the received signal strength received from the second network is less than a second threshold value.