Patent application number | Description | Published |
20080225895 | Apparatus and Method for Generating Signal According to Ifdma, and Apparatus for Receiving Signal - A signal generation apparatus and signal receiving apparatus according to an Interleaved Frequency Division Multiple Access scheme is provided. The signal generation apparatus generates a plurality of complex symbols by digital-modulating a plurality of data symbols, and rotates the generated plurality of complex symbols in a plurality of each different phase angles. The signal generation apparatus generates a plurality of transmission symbols by repeating a plurality of rotated complex symbols at predetermined times, and rotating the repeatedly generated plurality of transmission chips in phase angles of an orthogonal phase sequence for the respective users. When the signal receiving apparatus receives the plurality of transmission symbols generated as described above, the maximum diversity gain may be obtained. | 09-18-2008 |
20080285677 | Apparatus and Method For Transmitting Signals With Multiple Antennas - An apparatus for transmitting signals with multiple antennas is disclosed. The multiple antenna transmission apparatus performs space-time encoding or space-frequency encoding, and cyclically delays the encoded symbol with a plurality of delay-values to generate a plurality of delayed symbols. The multiple antenna transmission apparatus transmits the plurality of delayed symbols to the channel through a plurality of antennas. By changing the number of space areas for encoding and the number of delay-values for delaying, the number of antennas for the multiple antenna transmission apparatus is easily expanded. | 11-20-2008 |
20090185607 | METHOD FOR CHANNEL STATE FEEDBACK BY QUANTIZATION OF TIME-DOMAIN COEFFICIENTS - The present invention relates to a channel state transmission method using time domain coefficient quantization. A terminal measures channel information in the time domain and transmits it to a base station. In this instance, a multipath frequency selective fading channel is displayed in a tapped delay line format configured with a per-path path delay value and a path gain in the time domain, differentiates a quantization level for each path gain for more efficient transmission, quantizes the same, and transmits it to a transmitter. Therefore, while the amount of bandwidths required for transmitting state information from the terminal to the base station is reduced, the base station can efficiently acquire channel state information on the entire bandwidths. Also, the base station transmits signals to many terminals through beamforming by using the acquired reliable channel state information, thereby increasing the terminal's signal receiving performance. | 07-23-2009 |
20090202015 | TRANSMITTER HAVING FULL-DIVERSITY AND FULL-RATE, A LINEAR SPACE-TIME CODE GENERATING METHOD FOR THE TRANSMITTER, AND A MIMO SYSTEM USING SAME - A space-time code has a codeword matrix. The codeword matrix is a square matrix with dimension equal to the number of the transmit antennas, wherein a row of the codeword matrix represents combined signals transmitted by each transmit antenna and a column of the codeword matrix represents timeslots of the number of the transmit antennas. Signals are transmitted through the rows of the number of spatial multiplexing rate, in each column of the matrix. Further, the symbols of the number of the transmit antennas are combined by way of utilizing complex weights, in each row of the matrix. With this space-time code, a delay is minimized, so that change of channels can be managed efficiently. Also, the space-time code has minimum number of data symbols, and thus its complexity is minimized. | 08-13-2009 |
20090252240 | TRANSMITTING APPARATUS AND METHOD, AND RECEIVING APPARATUS AND METHOD IN MULTPLE ANTENNA SYSTEM - Respective codewords of quantization codebooks corresponding to a number of data streams are selected based on channel information estimated by a received training symbol. A stream mode is selected among stream modes to determine a modulation method applied to each data stream. The data stream is detected by using the codeword corresponding to the quantization codebook of the data stream corresponding to the selected stream mode as a precode matrix, and the detected data stream is modulated. In this case, a receiving apparatus performs a feedback operation so that indexes of the selected stream mode and the codeword used as the precode matrix may be transmitted to the transmitting apparatus. The transmitting apparatus selects the number of transmitted data streams and the modulation method based on the transmitted index of feedback streams by the feedback operation. | 10-08-2009 |
20100020892 | APPARATUS AND METHOD FOR GENERATING SYMBOL FOR MULTIPLE ANTENNAS - The present invention relates a symbol generation apparatus for multiple antennas having low receiving complexity and having flexibility with respect to an increase in the number of antennas. The symbol generation apparatus includes a plurality of space-time channel encoders respectively corresponding to a plurality of channels, and an inverse fast Fourier transformer group. The respective space-time channel encoders receive a digital-modulated symbol group from the corresponding channel, perform a space-time encoding operation with respect to a plurality of space areas and at least one time area, shift phases by using a plurality of phase values, and generate a plurality of phase-shifted space-time codewords. The inverse fast Fourier transformer group performs an inverse fast Fourier transform operation by using the plurality of phase-shifted space-time codewords in a plurality of subcarriers respectively corresponding to the plurality of channels, and generates a plurality of inverse fast Fourier transformed signals. | 01-28-2010 |
20100091896 | SIGNAL TRANSMISSION SYSTEM USING MULTIPLE ANTENNA AND SIGNAL TRANSMISSION METHOD THEREOF - The present invention relates to a multiple antenna transmission system and a signal transmission method In the signal transmission method using multiple antennas, a plurality of subcarrier symbols are grouped as a plurality of groups including first and second tiles that are basic resource management units including two or more subcarriers included in a set frequency domain, phases of subcarrier symbols included in a first tile are shifted to be a first phase shifting value, and phases of subcarrier symbols included in a second tile are shifted to be a second phase shifting value that is different from the first phase shifting value. | 04-15-2010 |
20100128776 | PULSE SHAPING METHOD - Provided is a pulse shaping method. A time interval is predefined so as to shape a pulse used for a transmit pulse and a receive filter response, a parameter is generated by using a weight coefficient and a plurality of cosine functions that are multiplied and added to be output during the predetermined time interval, and 0 is output during another interval, thereby shaping the pulse. The weight coefficient is updated by using the normalized MSE so as to shape the pulse to be optimized for the predetermined time interval. | 05-27-2010 |
20100279619 | INTER-CELL INTERFERENCE RELIEF METHOD - In a method of mitigating inter-cell interference, terminals are grouped into groups. A base station transmits data to a first terminal belonging to a first group among the groups, without cooperation with a neighboring base station. The base station transmits data to a second terminal belonging to a second group among the groups, through cooperation with the neighboring base station. | 11-04-2010 |
20100310001 | TRANSMITTING/RECEIVING METHOD FOR MULTI-USER MULTIPLE-INPUT MULTIPLE-OUTPUT SYSTEM - Disclosed is a transmitting/receiving method in a multi-user multiple-input multiple-output (MU-MIMO) channel. The transmitting method includes: performing QR decomposition on a Hermitian transpose matrix of a channel matrix to obtain a first matrix and a second matrix as a triangular matrix; obtaining a preprocessing matrix by using the first matrix; and forming an effective channel based on the preprocessing matrix by a block triangulation technique. | 12-09-2010 |
20110026628 | APPARATUS AND METHOD FOR MAPPING SYMBOL - In a symbol mapping method, transmission data is encoded to generate information bits and redundancy bits. An average LLR value of bits on which the information bits are mapped is different from an average LLR value of bits on which the redundancy bits are mapped. | 02-03-2011 |
20110033010 | APPARATUS AND METHOD FOR SELECTION OF PRECODING MATRIX - The present invention relates to an apparatus and a method for selection of a precoding matrix. In the present invention, a precoding matrix to enable an effective signal-to-noise ratio (ESNR) to have a maximum value with respect to a signal vector that requires retransmission is selected in a codebook and fed back to a transmitter. Accordingly, since the effective signal-to-noise ratio has the maximum value after the signal vector is retransmitted, it is possible to minimize a reception error probability of retransmission. | 02-10-2011 |
20110044301 | DEVICE AND METHOD FOR TRANSMITTING AND RECEIVING SYNCHRONIZATION CHANNEL - A method of transmitting a synchronization channel is provided. A plurality of block sequences for determining at least one block identifier is generated. A plurality of subcarriers of a synchronization channel are divided into a polarity of blocks, and the plurality of block sequences are allocated to the blocks to generate a synchronization signal. | 02-24-2011 |
20110102294 | METHOD OF DISPOSING MULTIPLE ANTENNAS AND COMMUNICATION APPARATUS USING THE METHOD - Provided is an apparatus and method that may dispose multiple antennas positioned in each of terminals in such a way that respective arrangements of the multiple antennas of the terminals are parallel to each other even when the terminal is rotated, thereby increasing a channel capacity. A transmission apparatus using the multiple antennas may include a first antenna unit to be disposed parallel to an arrangement of multiple antennas of a receiver while facing the arrangement of the multiple antennas of the receiver, and a second antenna unit where a transmission antenna is additionally disposed so that an arrangement of multiple antennas of a transmitter is parallel to the arrangement of the multiple antennas of the receiver while facing the arrangement of the multiple antennas of the receiver, when the transmitter is rotated. | 05-05-2011 |
20110142163 | APPARATUS AND METHOD FOR MAPPING SYMBOL - In a symbol mapping method, transmission data is encoded to output information bits and redundancy bits. The information bits and the redundancy bits are mapped to a symbol according to a first mapping scheme at a first transmission, and the information bits and the redundancy bits are mapped to a symbol according to a second mapping scheme at a second transmission. | 06-16-2011 |