Patent application number | Description | Published |
20100239036 | METHOD AND APPARATUS FOR TRANSMITTING PRECODING MATRIX INDEX IN A WIRELESS COMMUNICATION SYSTEM USING CoMP SCHEME - A method and apparatus for transmitting a Precoding Matrix Index (PMI) in a Coordinated Multi-Point (COMP) communication system are disclosed. The method includes receiving signals in a same frequency band from Base Stations (BSs) included in a CoMP set, which operate in joint processing mode, selecting a first precoding matrix for each of the BSs using the received signals, generating a second precoding matrix by combining the first precoding matrices, and transmitting an index of the second precoding matrix to a serving BS among the BSs. | 09-23-2010 |
20100254335 | METHOD OF TRANSMITTING CHANNEL STATE INFORMATION IN WIRELESS COMMUNICATION SYSTEM - A method of transmitting channel state information from a user equipment in a wireless communication system is disclosed. In order to report the channel state information, the user equipment is able to additionally transmit noise plus interference variance information as well as spatial channel matrix or spatial channel covariance matrix. The spatial channel matrix or spatial channel covariance matrix and the noise plus interference variance information can include information on a prescribed number of subbands in best channel states and can include information on a wideband including a plurality of subbands. Moreover, the user equipment is able to transmit normalized spatial channel matrix or spatial channel covariance matrix and normalized noise plus interference variance information for accurate and efficient transmission of the channel state information. | 10-07-2010 |
20100265901 | METHOD FOR TRANSMITTING CHANNEL STATE INFORMATION IN A WIRELESS COMMUNICATION SYSTEM - A method for transmitting channel state information from an user equipment in a wireless communication system is disclosed. The user equipment transmits a spatial channel matrix or a spatial channel covariance matrix irrespective of a feedback type. The user equipment is able to additionally transmit noise plus interference variance information of a whole bandwidth used for the channel state information. In this case, the user equipment is able to transmit normalized spatial channel matrix or spatial channel covariance matrix and normalized noise plus interference variance information for accurate and efficient transmission of the channel state information. The user equipment receives an allocation of an uplink resource from a base station and is then able to map the spatial channel matrix or the spatial channel covariance matrix to the allocated resource according to a specific pattern. | 10-21-2010 |
20100291940 | Apparatus and Method for Transmitting CoMP Feedback Information - A method of efficiently transmitting CoMP feedback information from an user equipment, which performs CoMP operation, in a wireless communication system to reduce inter-cell interference is disclosed. The user equipment requests a neighboring cell, which affects the user equipment through interference, to restrict use of a specific beam pattern group in a serving cell direction. In this case, whether the user equipment will request such restriction is determined based on a channel status value of the user equipment. If the user equipment determines to request such restriction, the user equipment transmits a request message to a serving base station, the request message requesting to restrict use of the specific beam pattern group. In this case, the user equipment performs scheduling and requests a specific neighboring cell to restrict use of the specific beam pattern group at a specific resource region. | 11-18-2010 |
20100311349 | Method for Estimating Channel State in a Wireless Communication System Using Fractional Frequency Reuse and Mobile Station Using the Same - A method for estimating channel state in a wireless communication system and a mobile station using the same are disclosed. The method includes acquiring cell Identifiers (IDs) of a serving cell and one or more neighbor cells, acquiring information about preset power level patterns for one or more frequency partitions to which FFR is applied according to the cell IDs, and estimating a channel state of the serving cell based on the power level pattern information. | 12-09-2010 |
20100323737 | METHOD OF PERFORMING FEEDBACK FOR MULTICAST AND BROADCAST SERVICE - A method of performing a feedback for a multicast and broadcast service (MBS) is disclosed. A Multicast Broadcast Service (MBS) feedback method includes, generating, by a base station contained in a multi-cell multicast broadcast single frequency network (MBSFN) zone, a ranging channel code for a multicast broadcast service (MBS) feedback, allocating the ranging channel code to a mobile station contained in a cell zone of the base station, and receiving the MBS feedback information based on the ranging channel code from the mobile station. So, an adaptive modulation and coding (AMC) is applied to the MBS according to the NACK feedback, such that a throughput of the MBS system increases. | 12-23-2010 |
20110090882 | METHOD AND APPARATUS FOR TRANSMITTING RECORDING INFORMATION FOR UPLINK TRANSMISSION IN MULTI BASE STATION MIMO SYSTEM - A PMI combination ratio (PCR) being used for generating a uplink precoding matrix W is transmitted by a base station to a mobile station. Using the PCR, a PMI maximizing transmission performance and PMI | 04-21-2011 |
20110103339 | Method for Allocating Resources for Edge-Users Cooperative Mimo - A method for allocating fractional frequency reuse (FER) resources to perform cooperative MIMO in a multi-cell environment is disclosed. A cell which requests FER resources decides a band for cooperative MIMO with its neighboring cell, and requests the neighboring cell to allocate the decided band for cooperative MIMO. A cell which receives FER resource request receives a request from a neighboring cell to allocate some or all of FER bands allocated to the neighboring cell as a band for cooperative MIMO, decides whether to grant the request, and allocates some or all of the requested FER bands as the band for cooperative MIMO with the neighboring cell if the request is granted. | 05-05-2011 |
20110164545 | MBMS FEEDBACK METHOD FOR E-MBS ADAPTATION - An MBS feedback method is disclosed. The MBS feedback method includes detecting one or more codes multiplexed in Code Division Multiplexing (CDM) from an MBS feedback channel, and adjusting a Modulation and Coding Scheme (MCS) based on the detected one or more codes. | 07-07-2011 |
20110200132 | MULTI-CELL BASED METHOD FOR APPLYING MULTI-CELL MIMO - The present invention relates a method for transmitting and receiving data in a mobile communication system. More specifically, the invention relates to a method through which a terminal in a cell boundary receives data in a mobile communication system that supports MIMO (Multi Input Multi Output). The method comprises: a step for receiving a first data stream transmitted through multiple transmission antennas from a serving base station, a step for pre-coding a second data stream to make the time delay of the second data stream be different from that of the first data stream and receiving the second data stream from a collaborating base station, and a step for restoring the data based on the first and second data streams. | 08-18-2011 |
20110201371 | METHOD AND APPARATUS FOR TRANSMITTING SIGNAL IN A WIRELESS COMMUNICATION SYSTEM USING COMP - A method for transmitting a signal to a UE by a BS in a wireless communication system is disclosed. The method includes determining a signal transmission scheme for transmitting a signal to the UE, dividing a basic resource allocation unit, if the signal transmission scheme is CoMP transmission, allocating transmission resources to the UE using the divided basic resource allocation unit, and transmitting the signal to the UE through the allocated transmission resources. | 08-18-2011 |
20110235608 | METHOD FOR TRANSMITTING AND RECEIVING A COMP REFERENCE SIGNAL IN A MULTI-CELL ENVIRONMENT - Disclosed is a channel estimation method using a cooperative multi-point (CoMP) reference signal in a multi-cell environment. The method comprises a CoMP reference signal receiving step of enabling a terminal to receive, from each of the cells that perform a CoMP operation, a CoMP reference signal where an orthogonal code is applied to each of the cells; a channel estimation step of enabling the terminal to estimate, using said CoMP reference signal, channels of each of the cells which perform said CoMP operation; and a channel status feedback information transmitting step of enabling the terminal to transmit channel status feedback information to each of the cells. | 09-29-2011 |
20110255436 | Method of Optimizing Comp Zone for Joint Processing Mode - A method of optimizing a CoMP Zone for a joint processing mode is disclosed. A method of optimizing a CoMP zone for a joint processing mode in a user equipment of a mobile communication system comprises transmitting information of at least one subband preferred by the user equipment among a plurality of subbands included in the CoMP zone, to a serving base station; receiving information of a specific subband included in the CoMP zone from the serving base station; and receiving data from at least one of the serving base station and neighboring base stations that support the CoMP, through a radio resource corresponding to the specific subband. | 10-20-2011 |
20110268068 | Method of Coordinating Precoding Matrixes in a Wireless Communication System - A method of coordinating precoding matrixes in a wireless communication system is disclosed. A method of coordinating precoding matrixes by a base station in a wireless communication system comprises receiving precoding matrix index information from neighbor cells; and generating PMI allocation for each resource according to the precoding matrix index information wherein at least one PMI is restricted or recommended in part of resource in the PMI allocation for each resource. | 11-03-2011 |
20110268073 | Method of Transmitting and Receiving Channel State Information Feedback in a Wireless Communication System - A method of transmitting and receiving channel state information feedback in a wireless communication system is disclosed. A method of transmitting channel state information (CSI) feedback by a user equipment receiver in a wireless communication system comprises mapping components of a CSI matrix to constellations; and allocating the mapped components to resource. | 11-03-2011 |
20110269407 | METHOD AND APPARATUS FOR INTER-CELL SYNCHRONIZATION IN A MULTI-CELL ENVIRONMENT - The present invention relates to a method for synchronizing multiple cells, which perform cooperative multi-input multi-output operations, as well as to a method for inter-cell synchronization in a multi-cell environment, comprising the steps of: measuring a propagation delay of a cooperative base station; transmitting the measured propagation delay to a serving base station; and receiving data for cooperative multi-input multi-output operations in which a transmission location is adjusted, on the basis of the propagation delay of the cooperative base station, when the serving base station transmits the propagation delay to the cooperative base station. | 11-03-2011 |
20110269459 | METHOD AND APPARATUS FOR DETERMINING CELL FOR EXECUTING COMP IN MULTI-CELL ENVIRONMENT - The present invention provides a method which determines an adjacent cell to carry out a coordinate multipoint transmission (CoMP) operation instead of performing the CoMP operation for all adjacent cells, in cases where precoding matrix indexes (PMI) of adjacent cells are limited to prevent interferences by adjacent cells in a multi-cell environment, thereby effectively reducing inter-cell interferences without causing an overhead. | 11-03-2011 |
20110274047 | Method for Receiving a Signal at a User Equipment (UE) in a Wireless Communication System - A method of receiving a signal at a user equipment (UE) from at least two cells in wireless communication system is disclosed. Receiving module may receive data and at least one reference signal from a CoMP (Coordinated Multi-Point) set including at least two cells. Decoding module may decode the received data and the received at least one reference signal. In this case, a power level of the data is same as a power level of the at least one reference signal, or a power ratio between the data and the at least one reference signal is a scaled value. Also, the power level of the data and the at least one reference signal are same for each of the at least two cells. A power ratio between the data and the at least one reference signal is a same scaled value for each of the at least two cells. | 11-10-2011 |
20110286398 | METHOD AND APPARATUS FOR TRANSMITTING CONTROL INFORMATION IN WIRELESS COMMUNICATIONS SYSTEM THAT SUPPORTS COORDINATED MULTI-POINT (COMP) INCLUDING MULTIPLE TRANSMISSION POINTS - The present system relates to a method for transmitting control information in a wireless communications system that supports coordinated multi-point (CoMP) including N (N>1) transmission points. The method comprises: generating control information for downlink transmission of the N transmission points; and transmitting the generated control information to a user device, wherein the control information contains a control information region for transmission of intrinsic control information on a reference transmission point among the N transmission points, and N−1 control information regions for transmission of intrinsic control information on the N−1 transmission points. | 11-24-2011 |
20110299622 | Low Overhead Feedback Scheme for Codebook Based Closed-Loop Mimo - The present invention relates to a Multi-Input Multi-Output (MIMO) communication system and more particularly, to a method for Correlation matrix feedback in a multi-cell wireless communication system. A method for transmitting correlation matrix feedback information of a mobile station considering adaptive feedback mode in a multi-cell wireless communication system according to one embodiment of the present invention comprises measuring a channel between the mobile station and a serving base station using a signal received from the serving base station; determining a first matrix indicating channel state information and a first precoder using the measured channel; generating a second matrix using a Fourier matrix and the first matrix; and transmitting feedback information including at least one of information of the first precoder and diagonal values of the second matrix. | 12-08-2011 |
20110305185 | Method of Transmitting and receiving Data in a Wireless System - A method of transmitting data in a wireless communication is disclosed, by which timing error can be solved in a multi-cell environment. The present invention, in which data is transmitted by a serving cell to a mobile station communicating with a plurality of cells in a wireless communication system, includes receiving information on delay times of signals from the mobile station, wherein the signals are received by the mobile station from the plurality of the cells and transmitting data to the mobile station by inserting a cyclic prefix (CP) having a length determined according to the information on the delay times into the data. | 12-15-2011 |
20110305223 | Method and Apparatus for Data Communication Through a Coordinated Multi-Point Transmission - The present invention relates to a method and an apparatus for data communication through a Coordinated Multi-Point Transmission in a multiple cell environment. According to the present invention, the data communication method through a coordinated multi-point transmission in a multiple cell environment including a serving base station and a cooperative base station for performing a coordinated multi-point transmission comprises the steps of: receiving data from the serving base station and the cooperative base station through a downlink channel; and demodulating the received data. Each datum transmitted from the serving base station and the cooperative base station includes a predetermined Reference Signal and a data Resource Element, and a Transmit Diversity is applied to the data resource elements of both the serving base station and the cooperative base station through Pairing. | 12-15-2011 |
20110305287 | Method of Transmitting Signal in a Wireless System - A method of transmitting a signal of a mobile station that performs communication with a plurality of cells in a wireless communication system comprises transmitting a control signal or a data signal through an asynchronous channel to a neighboring cell which is not synchronized with the mobile station, the asynchronous channel including cyclic prefix and guard time. | 12-15-2011 |
20120021738 | Method for Setting Control Multi Point in Wireless Communication System and Apparatus Thereof - The present invention relates to a method for setting a control multi point of a serving cell in a wireless communication system. The serving cell selects more than one adjacent base station as a control multi point set based on first link information between terminals and the adjacent base stations received from the terminals. Furthermore, the serving cell: receives a pre-coding matrix index corresponding to the adjacent base stations which is selected by the terminals, selects more than one pre-coding matrix index from the received pre-coding matrix indexes according to a preset condition, generates a pre-coding matrix index list, and transmits pre-coding matrix index list to the corresponding base station. | 01-26-2012 |
20120039287 | TRANSMISSION METHOD OF DOWNLINK REFERENCE SIGNAL AND APPARATUS THEREOF - The present invention relates to a wireless communication system, and provides a method and an apparatus for transmitting a downlink reference signal in the wireless communication system. The method for enabling a base station to transmit the reference signal to a terminal using layers of 8 or less in accordance with one embodiment of the present invention comprises the steps of: transmitting data for the layers of 8 or less through a data domain of a downlink sub frame; and transmitting a reference signal for the layers of 8 or less on a fixed OFDM symbol of the downlink sub frame, wherein the reference signal is a DRS (Dedicated Reference Signal) which demodulates the data for the layers of 8 or less, and the reference signal for the layers of 8 or less is separated into 1st and 2nd groups, and reference signals of the 1st and 2nd groups can be multiplexed in a CDM (Code Division Multiplexing) method on one resource element, respectively. | 02-16-2012 |
20120039292 | Method and Apparatus for Transmitting/Receiving Data in a Wireless Communication System - The present invention relates to a method and apparatus for transmitting/receiving data in a wireless communication system. According to one aspect of the present invention, a data receiving method is provided wherein a mobile station in a wireless communication system uses a frame including a first subframe in which a physical downlink shared channel (hereinafter, referred to as “PDSCH”) includes a first cyclic prefix (hereinafter, referred to as “CP”) and a second subframe in which the PDSCH includes a second CP, wherein the data receiving method comprises a step in which the mobile station receives information on the length of the first CP from a base station, receives data from the base station through the first subframe, and removes the CP of the data using the information on the length of the first CP. The first CP and the second CP have different lengths. | 02-16-2012 |
20120076039 | METHOD AND APPARATUS FOR TRANSMITTING SIGNAL USING SPATIAL SILENCING - The present invention relates to a method for transmitting signals in a heterogeneous network, the method comprising: a step wherein a base station determines a value-added vector for forming a beam pattern to be applied to a subsidiary carrier; a step wherein carrier operation information including information related to the determined value-added vector is transmitted via a primary carrier; and a step wherein the subsidiary carrier is transmitted by applying the determined value-added vector. | 03-29-2012 |
20120113951 | Method For Transmitting/Receiving A Comp Reference Singnal - Disclosed is a method for transmitting a CoMP reference signal for accurate channel estimation. The CoMP reference signal to be transmitted to a terminal which performs a CoMP operation in a multi-cell environment is a cell-specific reference signal or a CoMP-zone-specific reference signal. A method for transmitting the cell-specific reference signal uses an ID of a CoMP set constituted by cells that perform a CoMP operation, or does not apply a frequency shift value while using the ID of a relevant cell, or uses an ID of a serving cell or a frequency shift value of the serving cell. The cell-specific reference signal is transmitted using a preset specific resource region. A method for transmitting the CoMP-zone-specific reference signal is configured such that the pattern of the sequence of CoMP reference signals varies in each of the CoMP zones, and the pattern can be set in advance. In addition, the reference signal is multiplexed and transmitted using an orthogonal code resource in the event that reference signal is transmitted to a plurality of terminals using the same CoMP zone. | 05-10-2012 |
20120128050 | FEEDBACK SCHEME FOR MULTI-CELL INTERFERENCE MITIGATION CONSIDERATION LEGACY MOBILE USERS - The present invention relates to a Multi-Input Multi-Output (MIMO) communication system and more particularly, to a method for precoding matrix index (PMI) restriction/recommendation in a multi-cell wireless communication system. A method of codebook based precoding matrix index (PMI) feedback considering legacy mobile stations in a multi-cell wireless communication system comprises measuring a channel from at least one neighboring base station generating interference with a signal received from a serving base station; determining a first PMI in which the interference is maximized from PMIs included in a first codebook, wherein the first PMI is determined based on the measured channel; determining a first PMI group including PMIs having high correlation to the first PMI from the PMIs included in the first codebook; determining a second PMI in which the interference is maximized from PMIs included in a second codebook, where in the second codebook is for the legacy mobile stations; determining a second PMI group including PMIs having high correlation to the second PMI from the PMIs included in the second codebook; and transmitting feedback information including the first PMI, a first subset bit indicating the first PMI group, the second PMI and a second subset bit indicating the second PMI group to the serving base station. | 05-24-2012 |