| Patent application number | Description | Published |
| 20090059844 | METHOD OF TRANSMITTING DATA IN MULTIPLE ANTENNA SYSTEM - A method of transmitting data in a wireless communication system comprises receiving feedback data on an uplink data channel, the feedback data comprising a precoding matrix indicator (PMI), wherein the value of the PMI corresponds to an index in a codebook, transmitting a precoding scheme for downlink data on a downlink control channel, wherein the preceding scheme is determined as one of at least two of a transmit diversity irrespective of the received PMI, an acknowledgement indicating preceding according to the received PMI and a new PMI indicating that it is used in precoding downlink data to be transmitted, and transmitting the downlink data on a downlink data channel after applying precoding according to the determined preceding scheme. | 03-05-2009 |
| 20090190528 | METHOD FOR TRANSMITTING AND RECEIVING CHANNEL STATE INFORMATION PERIODICALLY OR APERIODICALLY - A method for transmitting and receiving channel state information (CSI) periodically and aperiodically is disclosed. The method for aperiodically transmitting channel state information (CSI) by a terminal includes receiving an indicator requesting a channel state information report of a downlink channel from a base station over a downlink control channel, and aperiodically transmitting the channel state information (CSI) to the base station over a physical uplink shared channel (PUSCH) upon receiving the indicator from the base station. | 07-30-2009 |
| 20090232239 | METHOD AND APPARATUS FOR TRANSMITTING A PILOT IN MULTI-ANTENNA SYSTEM - A method of transmitting a pilot method in a multi-antenna system is provided. The method comprises generating a preceding matrix including a preceding vector, the preceding vector being applied to each of data streams to be transmitted, performing preceding procedure for a pilot by using the preceding matrix, and transmitting the precoded pilot, wherein transmission power of the precoded pilot is determined specifically to the each of the data streams. The transmission power of a precoded pilot can be controlled adaptively, individually and independently for each channel to improve channel estimation performance. | 09-17-2009 |
| 20090245410 | Method for transmitting signals for reducing feedback overhead and method for transmitting feedback information for the same - A method for transmitting signals to reduce feedback overhead and a method for transmitting feedback information for the same are described. In transmitting signals through precoding, different codebook subsets are used in an open-loop transmission mode and a closed-loop transmission mode, thereby reducing feedback overhead. In this case, it is assumed that the codebook subsets for the respective transmission modes are optimized according to each transmission mode. | 10-01-2009 |
| 20090257383 | FEEDBACK METHOD FOR PERFORMING A FEEDBACK BY USING A CODEBOOK IN MIMO SYSTEM - A feedback method for performing a feedback by using a codebook in Multiple Input Multiple Output (MIMO) system includes receiving, by the mobile station, a MIMO mode type information, generating feedback information by using the codebook selected according to the MIMO mode type information, and transmitting the feedback information to the base station. The codebook includes a SU-MIMO codebook and a MU-MIMO codebook, and the MU-MIMO codebook is formed by extracting codebook elements from the SU-MIMO codebook. As a result, the method maximizes a system throughput simultaneously while effectively reducing an amount of feedback information. | 10-15-2009 |
| 20090257384 | METHOD FOR MODE ADAPTATION IN MIMO SYSTEM - A mode adaptation method for performing mode switching between a single-user MIMO (SU-MIMO) mode and a multi-user MIMO (MU-MIMO) mode includes reporting, by a base station, a MIMO feedback mode to a mobile station, receiving a feedback information determined on the basis of the MIMO feedback mode from the mobile station; and determining a MIMO feedback mode based on the feedback information. The MIMO feedback mode indicates whether it is single-user MIMO or multi-user MIMO and includes a number of mobile stations (MSs) transferred at one time. As a result, the method maximizes a system throughput simultaneously while effectively reducing an amount of feedback information. | 10-15-2009 |
| 20090262854 | Method for transmitting and receiving downlink control information - A method for efficiently transmitting and receiving downlink control information is disclosed. The method includes, at an base station, receiving feedback information including a preceding matrix index (PMI) from an user equipment (UE) and transmitting precoding information having a predetermined bit number according to the number of antenna ports and a transmission mode of the base station. The preceding information of a predetermined transmission mode in the preceding information includes confirmation information indicating that the base station uses a PMI which is recently received from the UE. At this time, if the confirmation information is transmitted via a specific resource block (RB) of an n | 10-22-2009 |
| 20090268698 | METHOD FOR MODE ADAPTATION IN MIMO SYSTEM - A mode adaptation method for performing mode switching between a single-user MIMO (SU-MIMO) mode and a multi-user MIMO (MU-MIMO) mode includes receiving, by the base station, a preferred MIMO mode related information from a mobile station; determining a MIMO mode based on the preferred MIMO mode related information; reporting the MIMO mode to the mobile station; and receiving a feedback information of the MIMO mode from the mobile station. | 10-29-2009 |
| 20090303928 | Method for transmitting channel information in wireless communication system - A method for transmitting uplink channel information in a wireless communication system is provided. The method comprises transmitting an adaptive modulation and coding (AMC) band bitmap indicating at least one AMC band selected from a plurality of AMC bands with a first transmission period through a plurality of uplink control channels and transmitting a channel quality indicator (CQI) based on transmission of the AMC band bitmap with a second transmission period through any one of the plurality of uplink control channels. | 12-10-2009 |
| 20100014481 | METHOD AND APPARATUS FOR TRANSMITTING REFERENCE SIGNAL, SETTING REFERENCE SIGNAL TRANSMISSION PATTERN, AND SETTING AND ALLOCATING RESOURCE BLOCK - A method for transmitting a reference signal, a method for establishing a reference-signal transmission pattern, and a method for establishing a block are disclosed. The reference-signal density is adjusted according to the request degree of the channel estimation performance, and then the reference signal is transmitted to a destination. As a result, the apparatus prevents prevent resources from being unnecessarily wasted, and acquires a high channel estimation performance as necessary, resulting in an increased production yield of a system. | 01-21-2010 |
| 20100031117 | Method for specifying transport block to codeword mapping and downlink signal transmission method using the same - A method for specifying a transport block-to-codeword mapping relationship and a method for transmitting a downlink signal using the same are described. If a swap flag has a first logic value, a first transport block is mapped to a first codeword and a second transport block is mapped to a second codeword. If the swap flag has a second logic value, the first transport block is mapped to the second codeword and the second transport block is mapped to the first codeword. If the size of any one of two transport blocks is 0, the swap flag is not used. | 02-04-2010 |
| 20100061482 | Method for transmitting data using phase shift based precoding and transceiver supporting the same - A method of transmitting data using cyclic delay in a multi-antenna system using a plurality of subcarriers and a transceiver supporting the same are disclosed. More particularly, a method of selecting a matrix (second matrix) for transforming a precoding matrix (first matrix) into a unitary matrix from a codebook by a prescribed reference is disclosed. An index for selecting the second matrix is calculated by a prescribed modulo operation in an open loop system or delivered as feedback information in a closed loop system. Diversity can be obtained by switching each column of the selected second matrix in accordance with time. In a multi-user system, a single second matrix can be determined by combining columns of the second matrix selected by each user. | 03-11-2010 |
| 20100103949 | METHOD OF ALLOCATING REFERENCE SIGNALS IN MIMO SYSTEM - There is provided a method of allocating reference signals in a multiple-input multiple-output (MIMO) system. The method includes allocating a first reference signal, a second reference signal and a third reference signal in a first OFDM symbol so that the first reference signal, the second reference signal and the third reference signal do not overlap with each other and allocating the first reference signal, the second reference signal and a fourth reference signal in a second OFDM symbol so that the first reference signal, the second reference signal and the fourth reference signal do not overlap with each other. The first reference signal and the second signal are allocated in a regular intervals in a single OFDM symbol. | 04-29-2010 |
| 20100118800 | METHOD FOR TRANSMITTING DOWNLINK CONTROL CHANNEL IN A MOBILE COMMUNICATIONS SYSTEM AND A METHOD FOR MAPPING THE CONTROL CHANNEL TO PHYSICAL RESOURCE USING BLOCK INTERLEAVER IN A MOBILE COMMUNICATIONS SYSTEM - A method for transmitting a downlink control channel in a mobile communication system and a method for mapping the control channel to physical resources using a block interleaver are provided. In order to transmit a downlink control channel in a mobile communication system, information bits are modulated to generate one or more modulation symbols according to a specific modulation scheme, the modulation symbols are interleaved using a block interleaver, and the interleaved modulated symbols are mapped to resource elements allocated for transmission of at least one control channel in a subframe, thereby transmitting the at least one control channel. | 05-13-2010 |
| 20100149961 | METHOD OFTRANSMITTING AND PROCESSING DATA AND TRANSMITTER IN A WIRELESS COMMUNICATION SYSTEM - A method for transmitting/processing data in a wireless communication system, and a transmitter are disclosed. A method processing method for data transmission at a transmitting side of a wireless communication system employing multiple carriers comprises performing a symbol mapping process on a binary data sequence, and generating a symbol sequence, converting the symbol sequence into a time-domain symbol using a plurality of sub-carriers having a variable sub-carrier spacing therebetween, and adding a cyclic prefix to the time-domain symbol. | 06-17-2010 |
| 20100166094 | Method for transmitting and receiving signals in open-loop spatial multiplexing mode - A method for transmitting and receiving signals in an open-loop spatial multiplexing transmission mode is described. If the number of transmit antennas is 2 and a rank is 2, a base station performs precoding according to a cyclic delay diversity scheme by a matrix in which a first matrix corresponding to an identity matrix, a second matrix corresponding to a diagonal matrix, and a third matrix corresponding to a unitary matrix are sequentially multiplied and transmits the precoded signals. This may be substantially the same as the case where the base station performs precoding using a matrix in which the second matrix corresponding to the diagonal matrix and the third matrix corresponding to the unitary matrix are multiplied and transmits the precoded signals. A user equipment estimates a transmission mode according to the received rank indicator and the number of transmit antennas and receives signals. | 07-01-2010 |
| 20100273514 | METHOD FOR PERFORMING CoMP OPERATION AND TRANSMITTING FEEDBACK INFORMATION IN A WIRELESS COMMUNICATION SYSTEM - A method for performing a Coordinated Multi-Point (CoMP) operation and transmitting feedback information in a wireless communication system is disclosed. The method includes measuring interference levels or noise and interference variances of reference signals received from one or more neighbor cells, and transmitting to a serving Base Station (BS) information about the measured interference levels or noise and interference variances, and information about a Precoding Matrix Index (PMI) that a mobile station (MS) wants to restrict or recommend for a neighbor cell performing the CoMP operation. | 10-28-2010 |
| 20100278278 | METHOD FOR SETTING PRECODER IN OPEN LOOP MIMO SYSTEM - A feedback method of a user equipment in an open loop Multiple-Input Multiple-Output (MIMO) system is disclosed. The method includes, receiving one of a plurality of modes determined according to types of resources to be used for performing feedback from a base station, and selecting a precoding matrix from a codebook subset corresponding to the received mode, applying the selected precoding matrix, and transmitting feedback information. Different codebook subsets are configured with respect to the plurality of modes, and the codebook subset is configured by extracting a predetermined number of elements from a base codebook based on a predetermined criterion considering the characteristics of the modes. | 11-04-2010 |
| 20100322349 | METHOD FOR TRANSMITTING DATA USING CYCLIC DELAY DIVERSITY - A method of transmitting data using cyclic delay in a multi-antenna system using a plurality of subcarriers is disclosed. Data is transmitted through a phase shift based precoding scheme enhanced from a related art phase shift diversity and a related art precoding scheme. A generalized cyclic delay diversity scheme is selectively applied to a phase shift based precoding scheme or a related art precoding scheme executed on a frequency domain is transferred to a time domain to be applied as a generalized cyclic delay diversity scheme. Accordingly, complexity of a receiver is reduced and communication efficiency can be enhanced. | 12-23-2010 |
| 20110026627 | METHOD OF TRANSMITTING MIDAMBLE - A method of transmitting a midamble for channel estimation of multiple antennas performed by a base station in a system having segregated uplink and downlink frequency bands is provided. The method includes transmitting midamble information indicating presence of the midamble within a downlink frame to a user equipment (UE), and transmitting the midamble on a single downlink subframe among at least one downlink subframe included in the downlink frame or on a common zone to the UE by using the multiple antennas. A scheduling overhead of a base station and other overheads can be reduced by decreasing the number of transmissions of a midamble on one downlink frame, and thus limited radio resources can be effectively used. | 02-03-2011 |
| 20110038320 | METHOD FOR ACQUIRING MULTI-CELL SPECIFIC MESSAGE IN WIRELESS COMMUNICATION SYSTEM - A method for acquiring a multi-cell specific message in a wireless communication system includes receiving a downlink preamble, receiving the multi-cell specific message weighted with the downlink preamble, and decoding the weighted multi-cell specific message by using the received downlink preamble. Accordingly, since a preamble is used to transmit a multi-cell specific message, there is no need to transmit an additional signal in order to estimate a channel of the multi-cell specific message. In addition, a user equipment can acquire the multi-cell specific message by simply performing decoding. | 02-17-2011 |
| 20110051824 | METHOD AND APPARATUS FOR PERFORMING HARQ IN A MULTIPLE ANTENNA SYSTEM - A method of performing hybrid automatic repeat request (HARQ) in a multiple-antenna system includes receiving a plurality of codewords through an uplink channel, generating acknowledgment (ACK)/not-acknowledgment (NACK) signals respectively for the plurality of codewords, and transmitting the plurality of ACK/NACK signals through a downlink channel in association with a resource used in transmission of the uplink channel. ACK/NACK signals for each codeword in multiple antenna system can be transmitted. | 03-03-2011 |
| 20110051834 | METHOD OF TRANSMITTING OF DATA AND CONFIGURING A CODEBOOK IN MULTI ANTENNA SYSTEM - Methods of controlling a transmission power and configuring a codebook in a multi-antenna system to solve a transmission power unbalance between antennas are disclosed. The method of transmitting data in a multi-antenna system includes (A) transmitting one or more pilot signals within a first symbol region through a first antenna unit, and (B) transmitting one or more pilot signals within a second symbol region through a second antenna unit, wherein data within the first symbol region is transmitted through the second antenna unit, and data within the second symbol region is transmitted through the first antenna unit. According to the present invention, since a transmission power unbalance between antennas is solved, a transmission power can be uniformly assigned to each antenna and channel estimation can be easily performed. Moreover, a power amplifier having a uniform amplification range can be used and designed. | 03-03-2011 |
| 20110064156 | METHOD OF TRANSMITTING FEEDBACK INFORMATION FOR PRECODING AND PRECODING METHOD - Precoding methods and method for performing precoding and methods of transmitting feedback information for precoding or transmitting a signal using a multi-codebook and method of transceiving precoding information in a multi-antenna system, where a signal transmitting method in a multi-antenna system, and more particularly, a method of transceiving precoding matrix information for a multi-input multi-output (MIMO) system is disclosed. The present invention proposes a method of performing communications using an expanded unitary matrix generated from shifting a phase of a base unitary matrix. The present invention is applicable to single user MIMO, multi-user MIMO, beam forming, etc. | 03-17-2011 |
| 20110064159 | METHOD AND APPARATUS FOR TRANSMITTING DOWNLINK SIGNAL IN A MIMO WIRELESS COMMUNICATION SYSTEM - A method and apparatus for transmitting a downlink signal in a multiple input multiple output (MIMO) wireless communication system is disclosed. A method for receiving a downlink signal from a base station to a user equipment in a multiple input multiple output (MIMO) system, which supports dual layer transmission based on first and second antenna ports, comprises receiving downlink control information (DCI) through a downlink control channel; and receiving downlink data through a downlink data channel, the downlink data including one or more of a first transport block and a second transport block, wherein the downlink control information includes a new data indicator (NDI) for each of the first and second transport blocks, and if the first transport block is disabled and the second transport block is enabled, the new data indicator for the first transport block indicates an antenna port through which the second transport block is received. | 03-17-2011 |
| 20110122825 | METHOD AND APPARATUS OF RECEIVING DATA IN WIRELESS COMMUNICATION SYSTEM - A method and an apparatus of receiving data in a wireless communication system are provided. The method includes detecting a physical downlink control channel (PDCCH) on which control information is transmitted in a first subframe, and receiving data in at least one second subframe based on the control information. | 05-26-2011 |
| 20110128917 | METHOD FOR TRANSMITTING DATA IN MULTIPLE ANTENNA SYSTEM - A method for transmitting data in a multiple antenna system comprises the steps of: generating a transmission signal in plural antennas through the application of a precoding eight matrix to first and second antenna clusters including the plural antennas, and transmitting the transmission signal. The precoding weight matrix is a block diagonal matrix that is configured in a precoding weight corresponding to first and second antenna clusters respectively. The precoding weight of the first antenna cluster is selected according to a channel condition, and the precoding weight of the second antenna cluster is selected regardless of the channel condition but according to a rule. | 06-02-2011 |
| 20110134867 | METHOD AND APPARATUS FOR TRANSMITTING REFERENCE SIGNAL IN MULTIPLE ANTENNA SYSTEM - A method and an apparatus for transmitting a reference signal in a multiple antenna system are provided. The method includes transmitting a first reference signal based on a first sequence through a first antenna group, and transmitting a second reference signal based on a second sequence through a second antenna group, wherein the first reference signal and the second reference signal are transmitted through a same radio resource. | 06-09-2011 |
| 20110135033 | METHOD FOR TRANSMITTING DATA IN MULTIPLE ANTENNA SYSTEM - A method of sending data in a multiple antenna system includes the steps of generating a transmission signal by applying channel-dependent precoding to a first antenna cluster and a second antenna cluster, each comprising a plurality of antennas, wherein the channel-dependent precoding is performed by a precoding weight matrix in which a precoding weight for each of the antenna clusters has a block diagonal form and the precoding weight is represented by P×V for a number of transmission antennas P, included in each of the antenna clusters, and a number of layers V applied to each of the antenna clusters (P and V are an integer greater than 0) and sending the transmission signal. | 06-09-2011 |