Abstract: A method for transmitting feedback information in a codebook-based multiple-input multiple-output (MIMO) system is disclosed. For example, a method for transmitting beamforming information in a MIMO system using a codebook-based beamforming scheme includes receiving a signal and estimating a reception channel, and transmitting beamforming information selected through the estimated channel information from a codebook which is updated using phase shift matrices having a phase value as a parameter and using previous beamforming information.

Abstract: A wireless communication system and more particularly a method for signals in a system using a plurality of antennas are disclosed. In the method for multi-antenna-encoding data symbols to be transmitted through the plurality of antennas, at least two same data symbols multi-antenna-encoded are formed and transmitted repeatedly. Accordingly, it is possible to enhance transmission efficiency.

Abstract: Repetitive transmissions in multi-carrier based wireless access techniques may be achieved by providing multiple cyclic delay values for a plurality of carriers, performing a cyclic delay procedure using the multiple cyclic delay values according to the number of repetitive transmission of data symbols to be transmitted to a receiver, and transmitting the cyclic delayed data symbols to the receiver using the plurality of carriers.

Abstract: A method of transmitting space-time coded data in a wireless communication system having a plurality of antennas is disclosed. More specifically, the method includes allocating data symbols combined with complex weights to at least two transmit antennas during at least one specified time slot, and transmitting the data symbols combined with complex weights to a receiving end via the at least two transmit antennas during the at least one specified time slot.

Abstract: An apparatus and method for authenticating a telematics terminal are disclosed to receive a first telematics service based on inputted user authentication information and then easily receive a second telematics service based on the inputted user authentication information. The method for authenticating a telematics terminal in a vehicle including: storing user authentication information inputted to receive a first telematics service through a mobile communication network; and requesting a second telematics service to an information providing center through the mobile communication network based on the stored user authentication information.

Abstract: A method for transmitting/receiving signals in a mobile communication system, a pilot configuration of a mobile communication system capable of transmitting much more data using a conventional pilot signal, a channel estimation method, and a receiving method are disclosed. A method for transmitting a signal equipped with a training symbol in a mobile communication system which includes a transmission end capable of transmitting an output signal equipped with a training symbol for channel estimation of a reception end, includes the steps of: a) adding training symbols having the same amplitude to data symbols transmitted via subcarriers, and calculating the output signal transmitted via the subcarriers; and b) transmitting the calculated output signal via the subcarriers.

Abstract: A method of transmitting a channel quality indicator (CQI) includes obtaining CQIs for each of a plurality of sub-bands, a sub-band comprising a plurality of sub-carriers, dividing the plurality of sub-bands into a plurality of layers according to a CQI of a sub-band, a layer comprising at least one sub-band, obtaining a representative value of a representative layer, the representative layer including a sub-band having maximum CQI and transmitting the representative value of the representative layer. Signaling overhead due to CQI feedback can be reduced.

Abstract: Query processing system and method by query transformation transform a user request query based on an original DB structure, destined to a DBMS of a DB with some columns encrypted, into a query based on an encrypted DB structure so that the DBMS processes the query. The query is processed irrespective of whether or not the query includes an encryption-related item, and query-processing performance is remarkably improved.

Abstract: A phase-shift based pre-coding scheme used in a transmitting side and a receiving side that has less complexity than those of a space-time coding scheme, that can support various spatial multiplexing rates while maintaining the advantages of the phase-shift diversity scheme, that has less channel sensitivity than that of the pre-coding scheme, and that only requires a low capacity codebook is provided.

Abstract: A phase-shift based pre-coding scheme used in a transmitting side and a receiving side that has less complexity than those of a space-time coding scheme, that can support various spatial multiplexing rates while maintaining the advantages of the phase-shift diversity scheme, that has less channel sensitivity than that of the pre-coding scheme, and that only requires a low capacity codebook is provided.

Abstract: A method of transmitting pilot symbols is disclosed. In a communication system performing communications using a plurality of antennas and multiple carriers, the present invention includes the steps of generating a plurality of pilot symbol sequences based on a basic code sequence, data-processing a plurality of the pilot symbol sequences by allocating each of a plurality of the pilot symbol sequences to the multiple carriers, and transmitting each of a plurality of the data-processed pilot symbol sequences via a corresponding one of a plurality of the antennas.

Abstract: A feedback method for a multi-antenna system is disclosed. The feedback method for use in the multi-antenna system can reduce an amount of transmission (Tx) feedback information associated with a precoding matrix (i.e., a codebook). For example, a single codebook may include precoding matrixes associated with several ranks. A basic matrix constructing the precoding matrix is extended to a frequency axis, such that it can be used as a Cyclic Delay Diversity (CDD) structure.

Abstract: A method for transmitting feedback information in a codebook-based multiple-input multiple-output (MIMO) system is disclosed. For example, a method for transmitting beamforming information in a MIMO system using a codebook-based beamforming scheme includes receiving a signal and estimating a reception channel, and transmitting beamforming information selected through the estimated channel information from a codebook which is updated using phase shift matrices having a phase value as a parameter and using previous beamforming information.

Abstract: 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 interval in a single OFDM symbol.

Abstract: 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.

Abstract: 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.

Abstract: Disclosed are methods of executing a handover related operation in a power saving mode in accordance with handover triggering information. One of the methods of executing handover of a mobile station in a mobile communication system comprises determining an enabled status of at least one handover related operation in a specific operation mode between the mobile station (MS) and a network, receiving control information related to the at least one handover related operation from the net work, entering the specific operation mode, changing the enabled status of the at least one handover related operation in the specific operation mode, and performing the enabled handover related operation in accordance with the changed enabled status and the control information.

Abstract: A method for transmitting a precoded signal in a collaborative multiple-input multiple-output (MIMO) communication system is described. A method for receiving a precoded signal in a MIMO communication system includes estimating, by a mobile station, channels for one or more base stations through signals received from the one or more base stations including a serving base station, transmitting precoding matrix indexes of the one or more base stations determined based on the estimated channels to the serving base station, and receiving signals precoded by the one or more base stations based on the precoding matrix index.

Abstract: A method of transmitting data using a phase shift-based precoding in a multiple antenna system using a plurality of subcarriers is disclosed. More specifically, the method includes determining a diagonal matrix to provide different phase angles to each of the plurality of antennas as a part of a phase shift-based precoding matrix, selecting a unitary matrix from a first codebook as the part of a phase shift-based precoding matrix, and performing precoding to symbols associated with subcarriers based on the diagonal matrix and the unitary matrix.

Abstract: This document is related to a method for receiving signals in multi-user system, the method comprising: receiving signals form 2 or more mobile stations using ‘k’-th radio resource and ‘k+m’-th radio resource; estimating a channel matrix using the received signals; calculating a weight matrix so that the channel matrix have an orthogonality to the signals from each of the mobile stations; transmitting the weight matrix to each of the mobile stations; and receiving signals that the weight matrix is applied by each of the mobile stations. By doing so, we can increase the transmission efficiency through obtaining both orthogonality and diversity gain in the multi-user MIMO system.