Patent application number | Description | Published |
20080205323 | Apparatus and method for resource allocation considering buffering in relay wireless communication system - A relay wireless communication system is provided. A Relay Station (RS) includes a buffer for storing packets to be sent to at least one Mobile Station (MS); a scheduler for allocating resources to the at least one mobile station of which the packets are stored to the buffer; a generator for generating a message which comprises information about at least one mobile station of which packets are not stored to the buffer; and a communicator for sending the message to a Base Station (BS) and sending the packets stored to the buffer to the at least one mobile station allocated the resources. | 08-28-2008 |
20080207117 | APPARATUS AND METHOD FOR SELECTING A RELAY MODE IN A MULTIHOP RELAY BROADBAND WIRELESS COMMUNICATION SYSTEM - An apparatus and a method for selecting one of a plurality of relay modes in a wireless communication system are provided. The method includes checking a channel state between a Mobile Station (MS) and each of at least one Relay Station (RS), selecting the relay mode for supporting a relay service using the determined channel state between the MA and each of the at least one RS, and providing the relay service to the MS using the selected relay mode. Thus, system throughput and outage performance can be enhanced by using the appropriate relay mode based on the MS distribution or the channel condition. | 08-28-2008 |
20080212515 | SYSTEM AND METHOD FOR TRANSMITTING AND RECEIVING SIGNALS IN A COMMUNICATION SYSTEM USING RELAY SCHEME - A system and method for transmitting and receiving a signal in a communication system using a relay scheme. A base station receives a first signal in a first time interval from a first mobile station which is at least one mobile station located in a third region which is a region where a first region which is a region of the base station itself overlaps with a second region which is a region of a relay station. The relay station receives a second signal in the first time interval from a second mobile station which is at least one mobile station located in a fourth region which is a region not overlapping with the first region in the second region, and receives the first signal from the first mobile station. The relay station transmits a third signal including the first signal and the second signal to the base station in a second time interval. The base station receives the third signal in the second time interval, and cancels the first signal from the third signal to detect the second signal. | 09-04-2008 |
20080227388 | METHOD AND APPARATUS FOR TRANSMITTING AND RECEIVING DATA USING MULTI-USER SUPERPOSITION CODING IN A WIRELESS RELAY SYSTEM - A method and apparatus for joint unicast using multi-user superposition coding in a wireless relay system are provided. A BS superposition-encodes first and second data messages directed to first and second MSs, respectively, scheduled at a current scheduling instant. The first and second data messages carry first and second information bit streams for the first and second MSs, respectively. The first MS has a relatively good direct link to the BS, and the second MS has a relatively bad direct link to the BS. The superposition-coded data is transmitted to the first MS and an RS connected between the BS and the first and second MSs. The RS receives the superposition-coded data from the BS, extracts the second information bit stream by decoding the superposition-coded data, and transmits a third data message carrying the second information bit stream to the first and second MSs. | 09-18-2008 |
20080232319 | SYSTEM AND METHOD FOR TRANSMITTING/RECEIVING RESOURCE ALLOCATION INFORMATION IN A WIRELESS MOBILE COMMUNICATION SYSTEM - A system for transmitting/receiving resource allocation information in a wireless mobile communication system is provided. A transmission apparatus allocates a data burst in a frame, the data burst including a two-dimensional region of a time domain and a frequency domain, and transmits resource allocation information on the allocated data burst. A reception apparatus receives the resource allocation information from the transmission apparatus, and detects a region of the frame where the data burst is allocated, using the received resource allocation information. The resource allocation information includes information on a start point and an end point of the data burst. The start point indicates a point which is spaced apart from an start point of the frame by a first offset value in the time domain, and is spaced apart from the start point of the frame by a second offset value in the frequency domain. The end point indicates a point which is spaced apart from the start point by a third offset value in the time domain, and is spaced apart from the start point by a fourth offset value in the frequency domain. The data burst is a two-dimensional rectangular region having a diagonal line segment connecting the start point to the end point. | 09-25-2008 |
20080234003 | APPARATUS AND METHOD FOR CANCELLING FREQUENCY OFFSET INTERFERENCE IN A BROADBAND WIRELESS COMMUNICATION SYSTEM - An apparatus and method for detecting a signal in a broadband wireless communication system are provided. In a Base Station, an offset estimator estimates frequency offsets of a signal received from each of a plurality of Mobile Stations (MSs), a channel estimator estimates a channel matrix having channel coefficients of subcarriers as elements, for each MS, a modeler models the received signals using the frequency offsets of the MSs and the channel matrices of the MSs, and a detector detects signals transmitted from the MSs using the modeled received signals. | 09-25-2008 |
20080267113 | RS-BASED NETWORK TRANSMISSION METHOD - A Relay System (RS)-based cellular network transmission method for MT having a function of single input and single output is provided. The method includes transmitting broadcast information to all RSs and Mobile Terminals (MTs); transmitting required data to each RS in an Orthogonal Frequency Division Multiplexing (OFDM) mode; performing the operations of selection of modulation scheme, addition of CP, addition of symbols for channel estimation and selection of OFDM symbols; feeding feedback information to the Base Station (BS); transmitting a synchronization request to the BS; transmitting a synchronization acknowledgement to the RS; transmitting information to each MT belonging to the BS; transmitting information to each MT belonging to the RS; the MT belonging to the BS transmitting ACK/NACK information to the BS; the MT belonging to the RS transmitting ACK/NACK information to the BS; and the BS informing the RS of the received ACK/NACK information. | 10-30-2008 |
20090010350 | APPARATUS AND METHOD FOR DETECTING SIGNAL USING MULTIVARIATE POLYNOMIAL IN MULTIPLE INPUT MULTIPLE OUTPUT COMMUNICATION SYSTEM - A signal detection apparatus and method in a Multiple Input Multiple Output (MIMO) wireless communication system are provided. The apparatus includes a receiver for receiving training symbol vectors and a data signal vector from a transmitting end through a plurality of receive (Rx) antennas and a detector for expanding the training symbol vectors into second- or higher-order polynomials, for generating a weighting parameter vector for multivariate polynomial expansion of the data signal vector by using the polynomials expanded from the training symbol vectors and thereafter for expanding the data signal vector into a second- or higher-order multivariate polynomial using the weighting parameter vector, and for detecting Transmit (Tx) values of the data signal vector from the multivariate polynomial. Therefore, signal detection performance in a Multiple Input Multiple Output (MIMO) wireless communication system resembles that of a non-linear scheme while complexity resembles that of a linear scheme. | 01-08-2009 |
20090011774 | Method and apparatus for estimating geo-location of terminal wireless communication system - A method and apparatus for estimating a geo-location of a terminal in a wireless communication system are provided. In a method of operating a terminal for providing geo-location information in a cognitive ratio (CR) system, the method includes obtaining first ranging information and transmitting a first ranging code to a base station (BS) in a network entry process; receiving an allocated second ranging resource from the BS; and transmitting a second ranging code. | 01-08-2009 |
20090011788 | Method and apparatus for jointly controlling transmit power in cognitive radio communication system - Provided is an apparatus and method for controlling power in a cognitive radio wireless communication system, the method comprising: performing channel scheduling and the first power control for at least one terminal; checking whether the at least one terminal exist within constraint area, and determining whether the at least one terminal within constraint area cause interference to incumbent system; and performing the secondary power control so that an allocating power may be less than the maximum tolerable interference. | 01-08-2009 |
20090207798 | Apparatus and method for allocating bursts in a broadband wireless communication system - A wireless communication system using multiple channels is provided. An apparatus includes an allocator for, when bursts are allocated to an Accessing Terminal (AT) which utilizes a plurality of channels at the same time, allocating the same amount of the bursts to each channel in use; a generator for, when a map message to be transmitted in a primary channel of the AT is generated, generating the map message which comprises allocation information of the bursts allocated to the AT; and a transmitter for transmitting the map message in the primary channel of the AT. | 08-20-2009 |
20090207800 | METHOD AND APPARATUS FOR CHANNEL MANAGEMENT IN COGNITIVE RADIO SYSTEM SUPPORTING MULTIPLE CHANNELS - A method and apparatus for channel management in a Cognitive Radio (CR) system supporting multiple channels are provided. The method includes generating a candidate channel set from an available channel list, configuring a backup channel set by combining at least one candidate channel, and updating the backup channel set when a channel change event occurs. Accordingly, the multiple channels can be effectively used in CR communication. | 08-20-2009 |
20090213007 | APPARATUS AND METHOD FOR TRANSMITTING COEXISTENCE BEACON PROTOCOL IN A COGNITIVE RADIO SYSTEM - An apparatus and method for transmitting Coexistence Beacon Protocol (CBP) in a cognitive radio system are provided. The apparatus includes a detector, a controller, and a transmitter. The detector scans channels on which neighboring Base Stations (BSs) operate through a plurality of directional antennas. The controller links the plurality of directional antennas with BSs, respectively. The transmitter receives a CBP packet through the directional antenna linked with the BS, and transmits the received CBP packet to at least one or more other BSs linked with at least one or more other directional antennas. | 08-27-2009 |
20090215451 | Apparatuses and methods for transmitting and receiving control information in a wireless communication system based on Cognitive Radio (CR) - A wireless communication system based on a Cognitive Radio (CR) is provided. A method includes checking channels unused by a licensed system through a spectrum sensing; selecting one of the channels unused by the licensed system as a control channel based on a channel quality per channel; and transmitting control information to terminals within a cell over the control channel. | 08-27-2009 |
20090221286 | Apparatus and method for controlling effect of interference in wireless communication system - An apparatus and a method for selecting a candidate channel to change an operating channel so as to minimize effect of interference in a wireless communication system using a Cognitive Radio (CR) function are provided. The method includes confirming an operating channel of at least one neighbor cell and candidate channel set to a third group by the neighbor cell; setting a candidate channel used as the operating channel of the neighbor cell among at least one candidate channels changeable to the operating channel, to a third group of lowest priority; setting candidate channels set to the third group of the neighbor cell among candidate channels not set to the third group, to a second group; and setting candidate channels set to neither the second group nor the third group, to a first group of highest priority. | 09-03-2009 |
20090279491 | Apparatus and method for transmitting coexistence beacon protocol packet incognitive radio-based wireless communication system - Provided are an apparatus and a method for transmitting a CBP packet for communication information sharing between base stations in a CR-based wireless communication system. In the method, a CBP packet including a CBP identifier is transmitted to a base station of adjacent cells via one SCW slot. A CBP identifier list for successfully received CBP packets is received from the base station of the adjacent cells. When the CBP identifier is included in the CBP identifier list, the SCW slot is occupied. | 11-12-2009 |
20090280748 | APPARATUS AND METHOD FOR ENQUIRING CHANNEL CONDITION INFORMATION IN COGNITIVE RADIO WIRELESS COMMUNICATION SYSTEM - A method of operating a Data Base (DB) server for storing spectrum condition information on a licensed system in a Cognitive Radio (CR)-based wireless communication system and a CR-based wireless communication system are provided. The method includes determining changes in the spectrum condition information on the licensed system, recalculating maximum Equivalent Isotropically Radiated Power (EIRP) allowed for each channel of CR-based devices registered in a list, and transmitting information regarding the recalculated maximum allowed EIRP. | 11-12-2009 |
20100008297 | APPARATUS AND METHOD FOR TRANSMITTING COEXISTENCE BEACON PROTOCOL PACKET IN COGNITIVE RADIO BASED WIRELESS COMMUNICATION SYSTEM - A method of and apparatus for operating a Coexistence Beacon Protocol (CBP) packet transmitter in a Cognitive Radio (CR)-based wireless communication system is provided. The method includes, identifying a Self-Coexistence Window (SCW) regular pattern of neighbor Wireless Regional Area Networks (WRANs), if vacant SCW slots are not periodically occurring, selecting a WRAN as a contender among the neighbor WRANs, performing a contention for transmitting the CBP packet with the contender within SCW slots that are occupied by the WRAN, and configuring an SCW usage pattern so that an SCW usage period of the CBP packet sender is double that of an SCW usage period of the contender when winning in the contention. | 01-14-2010 |
20100009692 | METHOD AND APPARATUS FOR FRAME BASED RESOURCE SHARING IN COGNITIVE RADIO COMMUNICATION SYSTEM - A frame structure, a method, and an apparatus for inter-frame resource sharing in a Cognitive Ratio (CR) communication system are provided. An apparatus for sharing a channel in an environment where a plurality of CR communication systems coexist, constitutes a Superframe Control Header (SCH), in one superframe, that includes a frame allocation MAP for frame information allocated to a Base Station (BS), with respect to each BS, and transmits and receives the SCH at the start frame of the frames allocated to the BSs. | 01-14-2010 |
20100118808 | Method and apparatus for inter-frame sharing in cognitive radio system - An operating method of a source Base Station (BS) for inter-frame sharing in a Cognitive Radio (CR) system includes generating a first random number for a frame contention; requesting the frame contention to one or more destination BSs by carrying the first random number; receiving responses for the frame contention request from the one or more destination BSs; and when positive responses for the frame contention request are received from all of the one or more destination BSs, occupying one or more requested contention frames. | 05-13-2010 |
20100118813 | METHOD AND APPARATUS FOR SWITCHING OPERATIONAL MODES IN A COGNITIVE RADIO SYSTEM - A method and apparatus for switching operational modes in a Cognitive Radio (CR) system are provided. A method for switching between a normal operation mode and a coexistence operation mode in a CR system includes occupying at least one channel in the normal operation mode, when there is no channel to be occupied, selecting at least one channel for the coexistence operation mode, and occupying available frames among frames of the selected at least one channel in the coexistence operation mode. | 05-13-2010 |
20100136974 | Apparatus and method for dynamic resource exchange in cognitive radio (CR) based communication system - A base station includes an apparatus and a method for exchanging frequency channel resources between base stations in a Cognitive Radio (CR) based communication system. A requesting Base Station (BS), which requests channel exchange a neighboring BS, receives a channel advertisement message from a neighboring BS and sends a channel exchange request message to the neighboring BS. The channel exchange request message includes at least one of a neighbor BS Identifier (ID), a requesting BS ID, channel information for the channel exchange at the requesting BS, and channel information exchangeable at the neighboring BS. The requesting BS receives a channel exchange response message from the neighboring BS in response to the channel exchange request message, determines whether to execute a channel exchange process to the neighboring BS based on information in the received channel exchange response message, and sends a channel exchange reply message indicative of the determination result. | 06-03-2010 |
20100203914 | Method and apparatus for synchronizing quiet period in cognitive radio system - A method and apparatus for sychronizing a Quiet Period (QP) in a Cognitive Radio (CR) system includes receiving QP information based on a channel N from at least one neighbor BS. The method further includes determining whether the channel N is an in-band channel. If the channel N is the in-band channel, QP scheduling is performed according to the received QP information based on the channel N. | 08-12-2010 |
20100214965 | APPARATUS AND METHOD FOR SUPPORTING PARTIAL FREQUENCY DIVISION DUPLEX IN A COGNITIVE RADIO WIRELESS COMMUNICATION SYSTEM - An operating method and apparatus of a Customer Premise Equipment (CPE) in a Cognitive Radio (CR) wireless communication system and a base station in the CR wireless communications system are provided. The method includes, when receiving a beacon message from a Primary User (PU), transmitting a mode change request message including a signal strength from the PU and a channel number interfering with the PU to a base station, when receiving a mode change reply message from the base station, determining whether a partial Frequency Division Duplex (FDD) scheme is applied, and, when the partial FDD scheme is applied, communicating by receiving a downlink burst in a Time Division Duplex (TDD) channel indicated by the mode change reply message and transmitting an uplink burst in an FDD channel indicated by the mode change reply message. | 08-26-2010 |
20100226312 | Apparatus and method for transmitting coexistence beacon protocol packet in cognitive radio wireless communication system - An apparatus and a method for transmitting a Coexistence Beacon Protocol (CBP) packet in a Cognitive Radio (CR) wireless communication system are provided. In the method for transmitting CBP packet in a transmitter that operates in a scalable Orthogonal Frequency Division Multiple Access (OFDMA) mode, a priority is given to each channel of one or more channels based at least partly upon channel use statuses of two or more neighbor Wireless Regional Area Networks (WRANs). Whether a Quality of Service (QoS) for CBP packet transmission for each channel is met is sequentially determined according to the respective priority. A channel having a highest priority is selected from the one or more channels meeting the QoS as a channel for CBP packet transmission. A CBP packet is transmitted via the selected channel. | 09-09-2010 |
20100232307 | Apparatus and method for semi distributed resource allocation in a cognitive radio wireless communication system - An apparatus and operation method of a Base Station (BS) for allocating a radio resource in a Cognitive Radio (CR) wireless communication system includes, when a licensed system is activated, determining whether each of User Terminals (UTs) located in a cell satisfies Quality of Service (QoS). If all of the UTs satisfy the QoS, a binary message indicating ‘on’ is broadcasted to neighbor BSs. If at least one of the UTs does not satisfy the QoS, a binary message indicating ‘off’ is broadcasted to the neighbor BSs, and when the binary message indicating ‘off’ is received from at least one of the neighbor BSs, the binary message indicating ‘off’ is broadcasted to the UTs. | 09-16-2010 |