Patent application number | Description | Published |
20080207194 | Apparatus and method for beamforming using sector common antenna in wireless communication system - 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. | 08-28-2008 |
20080298451 | APPARATUS AND METHOD FOR ESTIMATING CARRIER-TO-INTERFERENCE AND NOISE RATIO IN A COMMUNICATION SYSTEM - An apparatus and method for estimating a Carrier-to-Interference and Noise Ratio (CINR) in a communication system are provided. In the apparatus and method a signal having a traffic allocation available area that includes a preamble allocation available area is generated by Fast Fourier Transform (FFT)-processing a received symbol, power values of preamble tones included in the preamble allocation available area are calculated, a carrier power value is calculated using the power values of the preamble tones, a partial noise-interference power value is calculated using power differences between the preamble tones and power values of remaining tones other than the preamble tones, a noise power value is calculated using power values of tones included in a noise power estimation area being an area except for the preamble allocation available area in the traffic allocation available area, and the CINR is calculated using the carrier power value, the partial noise-interference power value, and the noise power value. | 12-04-2008 |
20090005093 | SYSTEM AND METHOD FOR ACQUIRING BASE STATION SYNCHRONIZATION IN A COMMUNICATION SYSTEM - A system and method for acquiring BS synchronization in a communication system are provided. In the system and method, a first BS acquires synchronization and transmits a frame to at least a second of the one or more neighbor BSs according to the synchronization, a second BS being the at least one neighbor BS estimates its first uplink frame synchronization time using a first arrival time of a downlink frame in the frame and transmits a first message at the first uplink frame synchronization time to the first BS, the first BS calculates a synchronization time difference by comparing a second arrival time of the first message with its uplink frame synchronization time and transmits a second message including the synchronization time difference to the second BS, and the second BS estimates a synchronization time using the synchronization time difference, acquires synchronization to the first BS, and transmits a frame generated with the same timing as the first BS. | 01-01-2009 |
20090005105 | APPARATUS AND METHOD FOR SETTING TRANSMIT POWER OF A COMPACT BASE STATION IN A WIRELESS COMMUNICATION SYSTEM - An apparatus and method for setting transmit power of a compact Base Station (BS) in a wireless communication system are provided. In the apparatus and method a measurer measures a signal strength corresponding to each of one or more neighbor BSs while operating in a Mobile Station (MS) mode, a receiver receives a signal strength corresponding to each of the one or more neighbor BSs measured by one or more MSs from the corresponding one or more MSs, and a self-configuration controller sets a target signal strength based on the signal strength corresponding to each of the one or more neighbor BSs measured in the MS mode and controls a transmit power so that the signal strength corresponding to each of the one or more neighbor BSs measured by the one or more MSs substantially reaches the target signal strength. | 01-01-2009 |
20090005108 | APPARATUS AND METHOD FOR DYNAMIC FREQUENCY ASSIGNMENT IN A WIRELESS COMMUNICATION SYSTEM - An apparatus and method for dynamic frequency assignment to a low-power Base Station (BS) in a wireless communication system are provided. The method includes receiving a Received Signal Strength Indication (RSSI) measurement result for the whole Frequency Assignment (FA) and an available FA set of the BS from the BS newly entering a network, selecting an FA having a minimum RSSI among FAs included in the available FA set, and assigning the FA having the minimum RSSI to the BS. | 01-01-2009 |
20090147733 | APPARATUS AND METHOD FOR ALLOCATING PREAMBLE INDEX TO SELF CONFIGURABLE BASE STATION IN A BROADBAND WIRELESS COMMUNICATION SYSTEM - 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. | 06-11-2009 |
20090239565 | APPARATUS AND METHOD FOR UPLINK BEAMFORMING AND SPACE-DIVISION MULTIPLE ACCESS (SDMA) IN MULTIPLE INPUT MULTIPLE OUTPUT (MIMO) WIRELESS COMMUNICATION SYSTEMS - 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. | 09-24-2009 |
20090270079 | Apparatus and method for updating neighbor list in a mobile communication system - 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. | 10-29-2009 |
20100040000 | Apparatus and method for allocating preamble index of self configuration base station in broadband wireless communication system - 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. | 02-18-2010 |
20100136996 | Apparatus and method for selecting frequency allocation of femto base station - 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. | 06-03-2010 |
20100202282 | Method and apparatus for ranging in Broadband wireless access communication system - 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. | 08-12-2010 |
20100254279 | APPARATUS AND METHOD FOR TRANSMITTING LOAD INDICATOR IN A BROADBAND WIRELESS COMMUNICATION SYSTEM - 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. | 10-07-2010 |
20110170442 | METHOD FOR ESTIMATING CARRIER-TO-NOISE RATIO AND BASE STATION APPARATUS USING THE SAME IN A WIRELESS ACCESS SYSTEM - 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. | 07-14-2011 |
20110183680 | SOUNDING SEQUENCE ALLOCATION METHOD IN WIRELESS COMMUNICATION SYSTEM AND CONTROL SYSTEM THEREOF - 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. | 07-28-2011 |
20110201378 | METHOD AND APPARATUS FOR CONTROLLING TRANSMIT POWER OF BASE STATION IN A WIRELESS COMMUNICATION SYSTEM - 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. | 08-18-2011 |
20110207492 | METHOD AND APPARATUS FOR SELECTING FREQUENCY ALLOCATION IN WIRELESS COMMUNICATION SYSTEM - 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. | 08-25-2011 |
20110216683 | APPARATUS AND METHOD FOR REDUCING INTERFERENCE AND SAVING ENERGY IN FEMTO/PICO CELL OF HIERARCHICAL CELL STRUCTURE - 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. | 09-08-2011 |
20110230226 | APPARATUS AND METHOD FOR CONTROLLING TRANSMIT POWER OF INDOOR BASE STATION IN A BROADBAND WIRELESS COMMUNICATION SYSTEM - 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. | 09-22-2011 |
20120093105 | METHOD AND APPARATUS FOR SUBBAND SCHEDULING IN WIRELESS COMMUNICATION SYSTEM - 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. | 04-19-2012 |
20120120806 | APPARATUS AND METHOD FOR LOAD BALANCING IN MULTI-CELL WIRELESS ACCESS SYSTEM - 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. | 05-17-2012 |
20120294214 | METHOD AND APPARATUS FOR SWITCHING A FREQUENCY ASSIGNMENT IN A WIRELESS COMMUNICATION SYSTEM - 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. | 11-22-2012 |
20140099942 | METHOD AND APPARATUS FOR DETECTING CELL OUTAGE AND CONTROLLING TRANSMISSION POWER - Disclosed are a method and an apparatus for detecting a cell outage and controlling transmission power. The method of detecting the cell outage includes: receiving a Radio Link Failure (RLF) message from a User Equipment (UE) or an adjacent BS; acquiring Reference Signal Received Power (RSRP) and Reference Signal Received Quality (RSRQ) of the UE with respect to a serving cell and adjacent cells before RLF generation, which are included in the RLF message; calculating a Signal to Interference plus Noise Ratio (SINR) of the serving cell by using the acquired RSRP and RSRQ; calculating an SINR of a best adjacent cell having a largest RSRP among the adjacent cells of the UE by using the acquired RSRP and RSRQ; and comparing an SINR of a best cell having a largest SINR between the serving cell and the best adjacent cell with a preset reference value and determining whether the cell outage has been generated. | 04-10-2014 |
20140099964 | APPARATUS AND METHOD FOR CONFIGURING CELL IN WIRELESS COMMUNICATION SYSTEM - A method for configuring a cell in a wireless communication system is provided. The method includes generating a virtual field based on information of a Remote Radio Header (RRH), generating grids in the virtual field at intervals, generating a virtual coverage map by regarding each of the grids as a virtual User Equipment (UE) and determining a serving RRH for each of the virtual UEs, determining grids which are located at a boundary region among RRHs among grids included in the virtual coverage map as boundary region grids, configuring a cell such that the cell includes less than or equal to a maximum sub-cell number of sub-cells, excluding boundary region grids included in a same cell among the boundary region grids from the boundary region grids, and selecting a sub-cell grouping combination which has a minimum number of boundary region grids among all sub-cell grouping combinations, and configuring the cell using the selected sub-cell grouping combination. | 04-10-2014 |