Abstract: An apparatus and method for beamforming in a wireless communication system are provided. The base station apparatus includes a calculator, a plurality of formers, and a plurality of adders. The calculator calculates a beam coefficient considering interference to a neighbor sector to be applied to transmission signals to mobile stations. The plurality of formers performs beamforming for a transmission signal to each mobile station within a corresponding sector using the beam coefficient. The plurality of adders adds the sector-based beamformed signals each provided from the plurality of formers, on a per-transmission-antenna basis.

Abstract: An apparatus and method for updating a neighbor list in a mobile communication system are provided. The system includes a Mobile Station (MS), a second Base Station (BS), and a first BS. The MS stores first log information, performs a network entry process with the second BS, and generates and transmits second log information to the second BS. The second BS allocates a bandwidth to the MS, receives the second log information, determines if neighbor list update is required using the second log information and, if the neighbor list update is required, updates a neighbor list and transmits the updated neighbor list information to the previous BS.

Abstract: A method and an apparatus for switching a Frequency Assignment (FA) by a base station in a wireless communication system are provided. The method includes, upon detecting movement of the base station, communicating with a mobile terminal using a first FA via a first FA-transceiver among a plurality of FA-transceivers which process signals transceived via each of the plurality of FAs, and selecting, upon detecting a change in a wireless environment caused by the movement, a second FA from among the plurality of FAs, operating a second FA-transceiver which processes signals transceived via the second FA, transmitting, to the mobile terminal, a scanning-instructing message for instructing the reference signal transmitted via the second FA to be scanned, and switching the first FA to the second FA in accordance with the result of the scanning received from the mobile terminal in response to the scanning-instructing message.

Abstract: An apparatus and method for allocating a preamble index to a self configurable base station in a broadband wireless communication system are provided. The apparatus comprises a first selector for selecting a segment IDentifier (ID) to be allocated to a Self Configurable-Base Station (SC-BS) by using a per-segment ID Received Signal Strength Indicator (RSSI) estimated by the SC-BS, a second selector for selecting an ID cell to be allocated to the SC-BS by using geographical location information of surrounding BSs, and a communicator for transmitting a segment ID and the ID cell to the SC-BS.

Abstract: An apparatus and method provide load balancing in a multi-cell wireless access system. The method includes determining a change value of a TX power, determining a handover candidate set including at least one MS to be handed over, calculating expected gains after TX power control for each MS classification, and determining whether to control the TX power based on the expected gains. The change value is zero or a positive real number.

Abstract: A method of scheduling a subband is provided. The method includes determining whether the eNodeB is in an overload state according to a used amount of a first radio resource of the eNodeB, receiving information on a used amount of a second radio source of at least one neighbor eNodeB from the at least one neighbor eNodeB, determining whether the at least one neighbor eNodeB is in the overload state, setting a number of total subbands to be used for a subband scheduling to a number lower than a number of total subbands used by the at least one neighbor eNodeB, setting a subband scheduling start order such that the subband scheduling is started from a subband having a farthest distance in frequency from at least one subband used by the at least one neighbor eNodeB from among the set number of subbands, and performing the subband scheduling.

Abstract: Provided is an apparatus and method for allocating a preamble index of a Self-Configuration or Self-Configurable (SC) Base Station (BS) in a broadband wireless communication system. An SC BS apparatus in a broadband wireless communication system includes a detector, a controller, and a generator. The detector detects at least one preamble signal for preamble index allocation by using a signal received from at least one other BS. The controller requests information used by at least one other SC BS for preamble index allocation and allocates a preamble index for the SC BS by using the detection result of the preamble signal and the information received from the at least one other SC BS. The generator generates a preamble signal corresponding to the preamble index allocated by the controller.

Abstract: An apparatus and method for beamforming of a terminal in a Multiple Input Multiple Output (MIMO) wireless communication system are provided. The method includes transmitting sounding signals beamformed through a plurality of beamforming weight vectors in sequence, receiving control information indicative of an uplink weight vector determined by a base station and a maximum channel quality value using the sounding signals and transmitting a transmit signal beamformed with the uplink weight vector via a plurality of antennas.

Abstract: A method and apparatus for controlling a Transmit power (TX power) of an indoor Base Station (BS) in a broadband wireless communication system. An operation of the indoor BS includes receiving received channel quality information on the indoor BS from at least one Mobile Station (MS), increasing in steps the TX power by as much as a basic unit amount and, determining whether an MS located outside a building has accessed the indoor BS using the received channel quality information in every increase and, when the MS located outside the building has accessed the indoor BS, decreasing the TX power of the indoor BS.

Abstract: An apparatus and method for estimating a Carrier-to-Interference and Noise Ratio (CINR) in a communication system are provided.

Abstract: An apparatus and a method manage power of a small base station. Whether a notify message indicating that a subscribed terminal enters a macro base station that includes an off-small base station is received from the macro base station under a closed access mode is determined. When the notify message is received, whether a service is providable to the subscribed terminal is determined. When the service is providable to the subscribed terminal, the small base station is turned on. During the closed access mode or when a load of a macro cell is large during an open access mode, when a terminal that should be serviced does not exist in the neighborhood of a small base station, an interference and power consumption unnecessarily generated may be reduced by turning off the small base station.

Abstract: A method and an apparatus select optimized Frequency Allocation (FA) in a mobile communication system that includes mobile base stations. A first control information is received from neighbor base stations. System capacities of the respective neighbor base stations are determined based on the first control information. The FA that maximizes a sum of the system capabilities of the respective neighbor base stations is selected. Therefore, the method has an advantage of securing maximum capacity by adaptively setting FA with consideration of radio environments of neighbor base stations during network entry of a new mobile base station or during an operation of a mobile base station.

Abstract: A method and apparatus for controlling the transmit power of a mobile BS in a wireless communication system are provided. The method includes determining a measurement value for determining if a noise power level is higher than an interference power level, when the measurement value is higher than a threshold value, determining that the noise power level is higher than the interference power level, and, when it is determined that the noise power level is higher than the interference power level, increasing transmit power.

Abstract: A sounding sequence allocation method in a base station of a wireless communication system and a control system thereof are provided. The method includes, determining a cyclic shift index set different from a cyclic shift index set used by at least one second indoor base station among the plurality of indoor base stations, determining a shift value different from a shift value used by at least one indoor base station located at a periphery, and allocating a sounding sequence with cyclic shift indexes included in the determined cyclic shift index set and the determined shift value to a first indoor base station. The method may provide sounding sequence allocation minimizing interference with another outdoor or indoor base station and reduce maintenance and management costs of a system.

Abstract: A method and an apparatus for estimating a Carrier-to-Noise Ratio (CNR) at a Base Station (BS) in a wireless access system are provided. In the method, a preamble signal received from at least one neighbor BS is converted to a frequency response of a preamble sequence and Inverse Fast Fourier Transform (IFFT)-processing the preamble signal, an estimation period of the IFFT-processed preamble signal, corresponding to a Fast Fourier Transform (FFT) size, is divided into a predetermined number of blocks, carrier power values of the blocks are accumulated for a predetermined number of frames, an average of timing offsets of the frames corresponding to a position of a block having a maximum average of accumulated carrier values is determined to be a timing offset of the preamble signal, a carrier power value of the preamble signal is calculated using the timing offset, and a CNR of the preamble signal is estimated using the carrier power value.

Abstract: Provided is an apparatus and method for power allocation in a Space Division Multiple Access (SDMA) system. The apparatus includes an encoder, an antenna weighting calculator, and an antenna. The antenna weighting calculator divides a transmission power of a Base Station (BS) by number of Mobile Stations (MSs), fixedly distributes the divided transmission powers to the MSs, calculates a surplus power of each MS, sums up the calculated surplus power to thereby calculate a total surplus power, calculates a power per MS needed for an MPR one level higher, determines whether there is an MS whose power needed for a next level MPR is smaller than the total surplus power, and additionally allocates the total surplus power when there is the MS.

Abstract: An apparatus for controlling a gain of transmit antennas in a communication system. The transmit antenna gain control apparatus includes a controller for determining a gain of multiple transmit antennas on a basis of a transmit antenna having a minimum currently unused residual power among currently unused residual powers of the multiple transmit antennas used in the communication system.

Abstract: A method and apparatus for providing load state information of a Base Station (BS) in a broadband wireless communication system are provided. The method includes determining a ratio of a whole allocated resource compared to a whole resource of the BS and a ratio of a resource allocated for a rate requiring security compared to the whole resource, generating at least one load indicator for indicating a first value expressing the ratio of the whole allocated resource and a second value expressing the ratio of the resource allocated for the rate requiring security, and transmitting the at least one load indicator.

Abstract: An apparatus and operation method of a Mobile Station (MS) for ranging in a broadband wireless access communication system includes receiving information for ranging code hopping from a Base Station (BS). The MS determines a hopping offset value that is a start of a ranging codes group using the information for ranging code hopping. The MS also determines a ranging codes group using the hopping offset value, and randomly selects at least one or more ranging codes among the determined ranging codes group and transmitting the selected ranging codes to the BS.

Abstract: A wireless communication network includes an apparatus and method for dynamically allocating frequencies of a femto Base Station (BS). An operation of the femto BS includes measuring received signal strength on system Frequency Allocations (FAs) of a plurality of macro BSs, determining maximum received signal strengths for the respective FAs, and determining an available FA set by using a result obtained from comparison between the maximum received signal strengths for the respective FAs with a first threshold.