Patent application number | Description | Published |
20080212530 | APPARATUS AND METHOD FOR FREQUENCY REUSE IN A MULTI INPUT MULTI OUTPUT SYSTEM - A frequency reuse apparatus and method for a Mobile Station (MS) using a multiple-antenna in a broadband wireless access communication system are provided. The method includes dividing a first frequency band into ‘N’ second frequency bands where ‘N’ equals a number of Base Stations (BSs); dividing each second frequency band into ‘n’ third frequency bands; allocating each of the ‘N’ second frequency bands according to the number of receive antennas; and allocating the third frequency bands to all of the BSs, respectively. | 09-04-2008 |
20080244350 | APPARATUS AND METHOD FOR AUTOMATIC REPEAT REQUEST IN MULTIPLE INPUT MULTIPLE OUTPUT SYSTEM - A method for an Automatic Repeat reQuest (ARQ) at a receiver in a Multiple Input Multiple Output (MIMO) system wherein when a received packet is erroneous and the erroneous packet is received from the weakest antenna in a Space Multiplexing (SM) mode, a first smallest number of retransmissions is computed to acquire a Signal to Noise Ratio (SNR) within or above an Adaptive Modulation and Coding (AMC) level. When the first number of the retransmissions is greater than a threshold, the sender is requested to retransmit the packets from the strongest antenna in the SM mode and when the first number of the retransmissions is smaller than the threshold, the sender is requested to retransmit the packets from the weakest antenna in the SM mode. | 10-02-2008 |
20080298490 | APPARATUS AND METHOD FOR REDUCING PEAK TO AVERAGE POWER RATIO IN AN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING SYSTEM - A method for reducing a Peak to Average Power Ratio (PAPR) using reserved tones in a transmission apparatus of an Orthogonal Frequency Division Multiplexing (OFDM) communication system is provided. The method includes detecting a subcarrier spacing interval and the number of spaced symbols based on a predetermined pilot pattern upon signal reception, and determining positions of shifted reserved tones obtained by shifting positions of reserved tones allocated to a predetermined symbol during the number of the spaced symbols at intervals of the spacing interval; determining an impulse waveform obtained by rotating a phase of a complex value of an impulse stored in a memory, using the determined positions of frequency-domain reserved tones of each symbol; calculating a subtrahend for a PAPR of an output signal using the phase-rotated impulse waveform; and reducing a PAPR of an input signal by performing a gradient algorithm using the phase-rotated impulse waveform. | 12-04-2008 |
20090125781 | APPARATUS AND METHOD FOR TRANSMITTING AND RECEIVING DATA IN A COMMUNICATION SYSTEM USING LOW DENSITY PARITY CHECK CODE - A method for transmitting data in a communication system using a Low Density Parity Check (LDPC) matrix includes generating an LDPC codeword by encoding information data bits, interleaving the LDPC codeword, mapping the interleaved LDPC codeword to a modulation signal, and generating a mapped signal by mapping the LDPC codeword bits separately to a bit corresponding to a real part and a bit corresponding to an imaginary part of said modulation signal, among bits constituting the modulation signal, generating a modulation signal by high-order-modulating the mapped signal and Radio Frequency (RF)-processing the modulation signal, and transmitting the RF-processed signal via a transmission antenna. | 05-14-2009 |
20090158129 | METHOD AND APPARATUS FOR ENCODING AND DECODING CHANNEL IN A COMMUNICATION SYSTEM USING LOW-DENSITY PARITY-CHECK CODES - A method for encoding a channel in a communication system using a Low-Density Parity-Check (LDPC) code. The method includes generating a plurality of column groups by grouping (categorizing) columns corresponding to an information word in a parity-check matrix of the LDPC code, and ordering the column groups; determining a range of an information word desired to be obtained by performing shortening; based on the determined range of the information word, performing column group-by-column group shortening on the column groups in order according to a predetermined shortening pattern; and LDPC encoding the shortened information word. | 06-18-2009 |
20090210767 | APPARATUS AND METHOD FOR ENCODING AND DECODING CHANNEL IN A COMMUNICATION SYSTEM USING LOW-DENSITY PARITY-CHECK CODES - An apparatus and method for generating a parity-check matrix of a Low-Density Parity-Check (LDPC) code are provided. Parameters for designing the LDPC code are determined, and a first parity-check matrix of a quasi-cyclic LDPC code is formed according to the determined parameters. A second parity-check matrix is created through the elimination of a predetermined portion of a parity part in the first parity-check matrix, and a third parity-check matrix is created by rearranging the second parity-check matrix. | 08-20-2009 |
20090217129 | METHOD AND APPARATUS FOR CHANNEL ENCODING AND DECODING IN A COMMUNICATION SYSTEM USING LOW-DENSITY-PARITY-CHECK CODES - A method and apparatus for encoding and decoding a channel in a communication system using a Low-Density Parity-Check (LDPC) code. The encoding method includes determining a modulation scheme for transmitting a symbol; determining a shortening pattern in consideration of the determined modulation scheme; grouping columns corresponding to an information word in a parity-check matrix of the LDPC code into a plurality of column groups; ordering the column groups; determining a range of a resulting information word desired to be obtained by shortening the information word; based on the range of the resulting information word, performing column group-by-column group shortening on the ordered column groups of the information word, according to the determined shortening pattern; and LDPC-encoding the shortened information word. | 08-27-2009 |
20090219884 | METHOD AND APPARATUS FOR TRANSMITTING/RECEIVING CONTROL INFORMATION IN A WIRELESS COMMUNICATION SYSTEM - A method and apparatus for transmitting/receiving control information in a wireless communication system are provided, in which physical layer signaling information to be transmitted in a frame is determined, a coded block is generated from signaling information having a fixed number of bits included in the physical layer signaling information, and a frame including the coded block is transmitted. The signaling information having the fixed number of bits includes information required for receiving other signaling information having a variable number of bits. | 09-03-2009 |
20090222706 | APPARATUS AND METHYOD FOR CHANNEL ENCODING AND DECODING IN COMMUNICATION SYSTEM USING LOW-DENISTY PARITY-CHECK CODES - An apparatus and a method for channel encoding/decoding in a communication system are provided. The apparatus and the method generate LDPC-encoded blocks with various lengths from an LDPC code with fixed length in a communication system using a Low-Density Parity-Check (LDPC) code. The apparatus and the method perform shortening using a predetermined number of shortened bits and perform LDPC encoding. The apparatus and the method apply predetermined rules according to the predetermined number of shortened bits and determine the number of bits to be punctured, and perform puncturing based on the determined number of punctured bits. | 09-03-2009 |
20090259913 | METHOD FOR ENCODING CONTROL INFORMATION IN A WIRELESS COMMUNICATION SYSTEM USING LOW DENSITY PARITY CHECK CODE, AND METHOD AND APPARATUS FOR TRANSMITTING AND RECEIVING THE CONTROL INFORMATION - A method and apparatus for transmitting control information in a wireless communication system using a Low Density Parity Check (LDPC) code is provided. The number of LDPC blocks, through which L1 post-signaling information is to be transmitted, is determined according to the total number of bits of the L1 post-signaling information. The number of input information bits of each LDPC block is calculated when the determined number of LDPC blocks is plural. The number of puncturing bits among parity bits of each LDPC block is determined considering a modulation order. A frame including one or multiple LDPC blocks generated through the preceding steps is transmitted. | 10-15-2009 |
20110107173 | APPARATUS AND METHOD FOR GENERATING A PARITY CHECK MATRIX IN A COMMUNICATION SYSTEM USING LINEAR BLOCK CODES, AND A TRANSMISSION/RECEPTION APPARATUS AND METHOD USING THE SAME - A method and apparatus are provided for generating a parity check matrix used to generate a linear block code in a communication system. The method includes determining a basic parameter of a second parity check matrix satisfying a rule predetermined with respect to a given first parity check matrix, generating a submatrix corresponding to a parity part of the second parity check matrix, using the basic parameter; and generating a submatrix corresponding to an information word part of the second parity check matrix, using the first parity check matrix and the basic parameter. | 05-05-2011 |
20110138262 | METHOD AND APPARATUS FOR CHANNEL ENCODING AND DECODING IN A COMMUNICATION SYSTEM USING A LOW-DENSITY PARITY CHECK CODE - A method is provided for channel encoding in a communication system using a Low-Density Parity Check (LDPC) code. The method includes grouping information bits into a plurality of groups; determining an order of the plurality of groups to be shortened, based on a ratio of a number of bits to be shortened to a number of bits to be punctured; determining a length of an information word to be obtained by shortening the plurality of groups; shortening the plurality of groups on a group basis in the determined order based on the determined length of the information word; and LDPC-encoding a shortened information word. | 06-09-2011 |
20120170596 | APPARATUS AND METHOD FOR SUPPORTING VARIABLE LENGTH OF TRANSPORT PACKET IN VIDEO AND AUDIO COMMUNICATION SYSTEM - Methods and apparatus are provided for supporting a variable-length transport packet in an Audio/Video (AV) communication system. Data to be transmitted is determined. It is determined whether a transport packet is the variable-length transport packet. A header having information indicating whether the transport packet is the variable-length transport packet is generated. When the transport packet is the variable-length transport packet, an optional header having length information of the transport packet is generated, and the data and the transport packet having the header and the optional header, are transmitted. When the transport packet is not the variable-length transport packet, the determined data and the transport packet having the header are transmitted. | 07-05-2012 |