Patent application number | Description | Published |
20080225962 | APPARATUS FOR GENERATING PRECODING MATRIX CODEBOOK FOR MIMO SYSTEM AND METHOD OF THE SAME - An apparatus for generating a precoding matrix codebook includes a matrix group generator to generate a first group of unitary matrices based on a vector-based codebook for precoding of a multiple input multiple output (MIMO) communication scheme; a matrix group extender to extend the first group of unitary matrices to generate a second group of unitary matrices; and a matrix group selector to select a group of columns corresponding to a communication rank from each of the unitary matrices that are elements of the second group so that the columns are optimized based on a distance between the columns corresponding to the communication rank. | 09-18-2008 |
20080242332 | DECENTRALIZED CONTROL OF FEEDBACK FOR MULTI-USER DIVERSITY - A communication apparatus includes a mobile terminal to measure a downlink channel state of a downlink between a base station and the mobile terminal, and to determine whether to transmit feedback information about the downlink channel state to the base station based on the measured downlink channel state. | 10-02-2008 |
20080247475 | METHOD FOR CODEBOOK DESIGN AND BEAMFORMING VECTOR SELECTION IN PER-USER UNITARY RATE CONTROL (PU2RC) SYSTEM - A base station includes a storage unit to store a codebook, wherein the codebook includes a plurality of matrices; a control unit to perform beamforming using the codebook to generate a signal; and a multi-antenna to transmit the signal. For all of the plurality of matrices, all column vectors of a same matrix of the plurality of matrices are orthogonal to each other. For all columns of the plurality of matrices, all column vectors of a same column of all of the plurality of matrices satisfy a Grassmannian line packing (GLP) criterion. | 10-09-2008 |
20080256163 | APPARATUS AND METHOD OF GENERATING CODEBOOK FOR MULTIPLE INPUT MULTIPLE OUTPUT COMMUNICATION SYSTEM - An apparatus and method of generating a codebook. The codebook generation apparatus includes a matrix extender to generate a candidate matrix set by multiplying a base matrix and at least one diagonal matrix, wherein the at least one diagonal matrix includes elements of a constrained set as diagonal elements; and a codebook generator to generate the codebook where a minimum distance between the elements is maximized, based on the candidate matrix set. According to aspects of the present invention, it is possible to provide a precoding codebook that can reduce an amount of feedback from a terminal. | 10-16-2008 |
20080317145 | MULTIPLE INPUT MULTIPLE OUTPUT COMMUNICATION SYSTEM AND A METHOD OF ADAPTIVELY GENERATING CODEBOOK - A Multiple-Input Multiple-Output (MIMO) communication system and a method of adaptively generating a codebook are provided. A terminal includes a channel estimator to estimate a channel formed between a base station and the terminal to calculate a channel matrix and a codebook generator to adaptively generate a codebook based on a spatial correlation matrix of the channel matrix. | 12-25-2008 |
20090238292 | MULTIPLE-INPUT MULTIPLE-OUTPUT COMMUNICATION SYSTEM CONTROL METHOD AND APPARATUS - A communication system control method, a communication system control apparatus and an apparatus for use in a communication system are provided. The communication system control apparatus includes an information collection unit to collect user set information about candidate user sets grouped by a plurality of base stations, and a scheduler to select target user sets corresponding to the plurality of base stations from among the candidate user sets based on an achievable sum data transmission rate of the plurality of base stations, and perform scheduling with respect to users included in the target user sets, the achievable sum data transmission rate being calculated based on the user set information. | 09-24-2009 |
20090268827 | SYSTEM FOR FEEDING BACK INDEX OF CODEWORD MATRIX - A system is provided for performing downlink beamforming based on information fed back by a mobile station. The mobile station includes a channel matrix generation unit to generate a channel matrix with respect to channels ranging from a base station to a mobile station, the base station including multiple transmission antennas, a codebook updating unit to generate a second codebook including a plurality of second codeword matrixes based on the generated channel matrix and a first codebook including a plurality of first codeword matrixes, a codeword selection unit to select at least one transmission codeword matrix from among the plurality of second codeword matrixes, a transmission unit to transmit an index of the selected transmission codeword matrix to the base station, and a receiving unit to receive data transmitted from the base station via the multiple transmission antennas. | 10-29-2009 |
20090268840 | MULTIPLE ANTENNA COMMUNICATION SYSTEM INCLUDING ADAPTIVE UPDATING AND CHANGING OF CODEBOOKS - Communication between a base station with multiple transmission antennas and a mobile station is provided. The base station and the mobile station may recognize or estimate, respectively, a channel between the base station and the mobile station, and update a previous codebook with a new codebook based on a variation of the channel. In this instance, the mobile station may provide feedback information to the base station using the new codebook, and the base station may generate a transmission signal for the mobile station using the new codebook and the feedback information. | 10-29-2009 |
20090323841 | CODEBOOK DESIGN METHOD FOR MULTIPLE INPUT MULTIPLE OUTPUT SYSTEM AND METHOD FOR USING THE CODEBOOK - A multiple input multiple output (MIMO) communication method using a codebook is provided. The MIMO communication method may use one or more codebooks and the codebooks may change according to a transmission rank, a channel state of a user terminal, and/or a number of feedback bits. The one or more codebooks may be adaptively updated according to a time correlation coefficient of a channel. | 12-31-2009 |
20100002643 | APPARATUS AND METHOD FOR INTER-CELL INTERFERENCE CANCELLATION IN MIMO WIRELESS COMMUNICATION SYSTEM - A method for operating a Mobile Station (MS) in a Multiple Input Multiple Output (MIMO) wireless communication system is provided. The method includes measuring channel quality for a serving Base Station (BS), if the channel quality is less than a threshold, measuring interference power from one or more neighbor BSs, determining a Precoding Matrix Index (PMI) and a priority metric for each neighbor BS, and feeding back at least one of the PMI, a PMI type indicator, the priority metric, and the channel quality to the serving BS. | 01-07-2010 |
20100045494 | USER TERMINAL AND BASE STATION USING ADAPTED CODEBOOK ACCORDING TO POLARIZATION - A terminal and a base station using an adaptive codebook for a polarization are provided. The terminal includes a rotation matrix generator to generate rotation matrices corresponding to a cross polarization discrimination value (XPD) of a transmission signal and a codebook generator to generate a codebook including result matrices that are generated based on pre-stored block diagonal matrices and the rotation matrices. | 02-25-2010 |
20100098144 | MULTIPLE INPUT MULTIPLE OUTPUT COMMUNICATION SYSTEM AND COMMUNICATION METHOD OF ADAPTABLY TRANSFORMING CODEBOOK - A multiple input multiple output (MIMO) communication system including a base station and at least one terminal may adaptively transform a codebook. The terminal may calculate one or more correlation matrices based on one or more subchannel matrices included in a channel matrix. The terminal may feed back information for the base station to reconstruct the one or more correlation matrices. The terminal may transform a codebook stored in the memory of the terminal, based on the one or more correlation matrices. The base station may verify the one or more correlation matrices using the information for the base station to reconstruct the one or more correlation matrices. The base station may transform a codebook stored in the memory of the base station such that the transformed base station codebook is the same as the transformed terminal codebook. | 04-22-2010 |
20100104032 | CODEBOOK DESIGN METHOD FOR MULTIPLE INPUT MULTIPLE OUTPUT SYSTEM AND METHOD FOR USING THE CODEBOOK - A multiple input multiple output (MIMO) communication method using a codebook is provided. The MIMO communication method may use one or more codebooks and the codebooks may change according to a transmission rank, a channel state of a user terminal, and/or a number of feedback bits. | 04-29-2010 |
20110058621 | CODEBOOK GENERATING METHOD AND APPARATUS FOR GENERATING A CODEBOOK FOR MULTI-POLARIZED MULTIPLE-INPUT MULTIPLE-OUTPUT (MIMO) SYSTEMS - A communication apparatus and method include: selecting, as a precoding matrix, one of pre-stored at least one matrix W | 03-10-2011 |
20110096851 | CODEBOOK GENERATING METHOD AND APPARATUS FOR GENERATING A CODEBOOK FOR MULTI-POLARIZED MULTIPLE-INPUT MULTIPLE-OUTPUT (MIMO) SYSTEMS - A communication apparatus and method include: selecting, as a precoding matrix, one of pre-stored at least one matrix W | 04-28-2011 |
20110268207 | MULTIPLE INPUT MULTIPLE OUTPUT COMMUNICATION SYSTEM USING CODEBOOK CORRESPONDING TO EACH REPORTING MODE - A multiple input multiple output (MIMO) communication system using a first codebook and a second codebook is provided. The first codebook and the second codebook may independently exist, or may exist in a form of an overall codebook in which the first codebook and the second codebook are integrated with each other. A receiver may extract a first precoding matrix indicator from the first codebook, and may extract a second precoding matrix indicator from the second codebook. The receiver may also extract the first precoding matrix indicator and the second precoding matrix indicator from the overall codebook. The first precoding matrix indicator and the second precoding matrix indicator may be fed back to a transmitter. The transmitter may determine a precoding matrix based on the first precoding matrix indicator and the second precoding matrix indicator. | 11-03-2011 |
20120069919 | CODEBOOK GENERATING METHOD AND APPARATUS FOR GENERATING A CODEBOOK FOR MULTI-POLARIZED MULTIPLE-INPUT MULTIPLE-OUTPUT (MIMO) SYSTEMS - A method of generating a codebook for a multiple-input multiple-output (MIMO) system is provided. The codebook generation method includes: assigning a single-polarized precoding matrix to diagonal blocks among a plurality of blocks arranged in a block diagonal format in which a number of diagonal blocks corresponds to a number of polarization directions of transmitting antennas; and assigning a zero matrix to remaining blocks excluding the diagonal blocks. | 03-22-2012 |
20130100996 | CODEBOOK GENERATING METHOD AND APPARATUS FOR GENERATING A CODEBOOK FOR MULTI-POLARIZED MULTIPLE-INPUT MULTIPLE-OUTPUT (MIMO) SYSTEMS - A terminal and method for generating a codebook for a multiple-input multiple-output (MIMO) system is provided. The codebook generation includes: assigning a single-polarized precoding matrix to diagonal blocks among a plurality of blocks arranged in a block diagonal format in which a number of diagonal blocks corresponds to a number of polarization directions of transmitting antennas; and assigning a zero matrix to remaining blocks excluding the diagonal blocks. | 04-25-2013 |
20130266084 | CODEBOOK DESIGN METHOD FOR MULTIPLE INPUT MULTIPLE OUTPUT SYSTEM AND METHOD FOR USING THE CODEBOOK - A multiple input multiple output (MIMO) communication method using a codebook is provided. The MIMO communication method may use one or more codebooks and the codebooks may change according to a transmission rank, a channel state of a user terminal, and/or a number of feedback bits. The one or more codebooks may be adaptively updated according to a time correlation coefficient of a channel. | 10-10-2013 |