Patent application number | Description | Published |
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 |
20090063929 | Apparatus and method for transmitting and receiving data in a communication system using low density parity check codes - An apparatus for transmitting data in a communication system using a Low Density Parity Check (LDPC) matrix is provided. The apparatus includes an interleaver for interleaving a descending bit-ordered codeword having a predetermined size and in accordance with a predetermined modulation scheme; and a bit mapper for mapping codeword bits constituting the interleaved codeword in accordance with a predetermined mapping scheme that takes into account degrees of the codeword bits and reliability characteristics of modulation symbol-constituting bits based on the predetermined modulation scheme. | 03-05-2009 |
20100135422 | PREAMBLE TRANSMISSION AND RECEPTION METHOD AND APPARATUS FOR OFDM SYSTEM - A method and apparatus for transmitting and receiving a preamble having sequence information for an OFDM system is provided. The preamble transmission method includes generating a preamble block including at least one frame having a header with a known sequence and a code block containing control information and transmitting the preamble block mapped to Orthogonal Frequency Division Multiplexing (OFDM) cells by repeating in frequency axis direction. | 06-03-2010 |
20100138720 | CHANNEL-ENCODING/DECODING APPARATUS AND METHOD USING LOW-DENSITY PARITY-CHECK CODES - An encoding/decoding apparatus and method using a low-density parity-check code (LDPC code) is disclosed. Basic column group information, serving as a set of information regarding positions of rows with weight 1, is extracted from a reference column in each column group of a predetermined parity-check matrix. Column group information transforms the positions of rows with weight 1 into positions whose lengths are within a required parity length. A parity-check matrix is generated according to the generated column group information. Data is encoded or decoded based on the generated parity-check matrix. | 06-03-2010 |
20100153813 | COMMUNICATION METHOD AND APPARATUS USING LDPC CODE - An encoding method using a Low Density Parity Check (LDPC) matrix having a codeword length of N and an information word length K is provided to improve coding efficiency, and includes generating a first parity bit vector ( | 06-17-2010 |
20100158047 | URGENT PACKET TRANSMISSION/RECEPTION APPARATUS AND METHOD FOR DIGITAL BROADCAST SYSTEM - An apparatus and method for transmitting/receiving an urgent packet in a digital broadcast system is provided. A packet transmission apparatus of a digital broadcast transmitter includes a buffer which buffers broadcast packets; an urgent packet generator which generates an urgent packet having an urgent packet header indicating the urgent packet when a packet containing urgent data is detected; and a frame generator which generates a frame with the broadcast packets and inserts the urgent packet into the frame, wherein the urgent packet is substituted for one of broadcast packets in the frame. | 06-24-2010 |
20100162073 | BIT MAPPING/DEMAPPING METHOD AND APPARATUS FOR COMMUNICATION SYSTEM - An improved bit mapping method and apparatus for a communication system is provided. A bit mapping method of the present invention includes arranging coded bits in a codeword in an order of recovery capability; setting a shift region including a number of coded bits; rearranging the coded bits in the shift region by shifting the shift region by a number of bits equal to a number of bits that is indicated by a shift factor; and mapping the rearranged coded bits into a modulation symbol in an order of reliability from a lowest reliability bit position to a highest reliability bit position of the modulation symbol. | 06-24-2010 |
20100195758 | DIGITAL VIDEO BROADCASTING-CABLE SYSTEM AND METHOD FOR PROCESSING RESERVED TONE - A Digital Video Broadcasting-Cable (DVB-C) system and a processing method for reserved tones are provided. A transmitter determines a position of broadcast data and a position of reserved tones in a frame and sends a broadcast signal into which the broadcast data and the reserved tones are inserted. A receiver determines the position of reserved tones in a received broadcast signal and extracts broadcast data from the broadcast signal in consideration of the determined position of the reserved tones. The system and method may compensate for the peak power of broadcast data to be transmitted through a multi-channel bundle, by inserting reserved tones into the whole multi-channel bundle with combined channel bands. This may reduce the Peak to Average Power Ratio (PAPR) of broadcast signals in the DVB-C system and thereby improve the performance of the DVB-C system while still adopting Orthogonal Frequency Division Multiplexing (OFDM). | 08-05-2010 |
20100202390 | MOBILE BROADCAST SYSTEM FOR SUPPORTING IRREGULAR INTERVAL BROADCAST SERVICE AND IN-BAND SIGNALING METHOD AND APPARATUS THEREFOR - An in-band signaling method and apparatus of a mobile broadcast system supporting irregular interval broadcast services is provided for facilitating channel switching of a mobile device. An in-band signaling method for a mobile broadcast system according to the present invention includes generating scheduling information of Physical Layer Pipes (PLPs) transmitted at irregular intervals, the scheduling information including a next frame index and a first frame flag, inserting the scheduling information into a control information of a current frame and multiplexing broadcast service traffic of the PLPs and the control information. | 08-12-2010 |
20100202545 | Power distribution method and apparatus for OFDM system - An apparatus is capable of distributing power over a number of subcarriers in an OFDM system. The transmission power control method for an Orthogonal Frequency Division Multiplexing (OFDM) communication system according to the present invention includes measuring, at a receiver, channel coefficients of subcarriers, classifying the subcarriers into a predetermined number of groups according to sizes of channel coefficients, generating group indices, and transmitting the group indices of the subcarriers to a transmitter. A transmitter is capable of receiving the group indices of the subcarriers, determining per-group transmission powers, allocating the per-group transmission powers to the corresponding groups, distributing the per-group transmission power over subcarriers in the same level within respective groups, and transmitting signals over the subcarriers with the distributed power level. | 08-12-2010 |
20100232544 | METHOD FOR ENCODING CONTROL INFORMATION IN A COMMUNICATION SYSTEM, AND METHOD AND APPARATUS FOR TRANSMITTING AND RECEIVING THE CONTROL INFORMATION - A method and apparatus is provided for encoding and transmitting control information in a communication system, in which a number of coded blocks for carrying the control information is determined based on a number of bits of the control information and a specific reference value. The number of information bits corresponding to the coded blocks is calculated based on the determined number of coded blocks, the number of parity bits to be punctured in the coded blocks is calculated, and a frame including at least one of the coded blocks is transmitted. | 09-16-2010 |
20110119568 | METHOD AND APPARATUS FOR TRANSMITTING AND RECEIVING DATA IN A COMMUNICATION SYSTEM - A method is provided for transmitting data, which improves a diversity effect in a communication system. The method includes transmitting an information word including a codeword in a (k+s)-th frame, generating s groups based on parity bits obtained by encoding the information word, and transmitting the s groups in s frames preceding the (k+s)-th frame, in a distributed manner. | 05-19-2011 |
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 |
20110283158 | APPARATUS AND METHOD FOR LAYERED DECODING IN A COMMUNICATION SYSTEM USING LOW-DENSITY PARITY-CHECK CODES - A channel decoding apparatus and method in a communication system using Low-Density Parity-Check (LDPC) codes are provided in which an encoded signal is received from a transmitter and decoded using a parity-check matrix. At least one of input orders and output orders of the parity-check matrix are determined so that same values are not overlapped in a column direction between the at least one of the input orders and the output orders. | 11-17-2011 |
20120140769 | APPARATUS AND METHOD FOR SUPPORTING VARIABLE LENGTH OF TRANSPORT PACKET IN AN AUDIO AND VIDEO COMMUNICATION SYSTEM - Methods and apparatus are provided for supporting a variable-length transport packet in a audio and video communication system. Data to be transmitted through a transport packet is determined. A header of the transport packet is generated. The header includes a start sync signal. When a length of the transport packet exceeds a reference size, at least one intermediate sync signal is inserted into the transport packet according to a pre-defined interval. The transport packet is transmitted. | 06-07-2012 |
20120144265 | APPARATUS AND METHOD FOR INDICATING A PACKET ERROR IN AN AUDIO AND VIDEO COMMUNICATION SYSTEM - An apparatus and method are provided for indicating an error of a transport packet in an audio and video communication system. The method includes receiving a frame including a transport packet, attempting Forward Error Correction (FEC) on the frame, and setting a value of an error indicating field in the transport packet according to a result of the FEC. The error indicating field includes at least one of a first flag indicating a presence or absence of an error in the transport packet, a second flag indicating a success or failure of the FEC, and a third flag indicating detection or non-detection of a Cyclic Redundancy Check (CRC). | 06-07-2012 |
20120166905 | METHOD AND APPARATUS FOR CONTROLLING DECODING IN RECEIVER - Methods and apparatus are provided for controlling decoding in a receiver. A codeword is received and decoded. It is determined whether the decoding is a decoding success or a decoding failure. A number of unreliable bits of the codeword is determined when the decoding is the decoding failure. Iterative decoding is performed when the number of unreliable bits is less than a first threshold value. | 06-28-2012 |
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 |
20120173948 | APPARATUS AND METHOD FOR CHANNEL ENCODING AND DECODING BASED ON LOW-DENSITY PARITY CHECK CODE IN MULTIPLE ANTENNA COMMUNICATION SYSTEM - Methods and apparatuses are provided for achieving maximum diversity gain through channel coding based on a Low-Density Parity-Check (LDPC) code in a multiple antenna communication system. A method includes determining a parity-check matrix; generating a codeword using the parity-check matrix; puncturing a part of an information word; dividing a parity into a plurality of partial parities based on a number of transmit antennas; transmitting an unpunctured part of the information word and a partial parity over a first antenna; and transmitting at least one other partial parity over at least one other transmit antenna. | 07-05-2012 |
20120179948 | METHOD AND APPARATUS FOR CHANNEL ENCODING AND DECODING IN A BROADCASTING/COMMUNICATION SYSTEM USING LOW DENSITY PARITY-CHECK CODES - An apparatus and a method are provided for encoding and decoding in a broadcasting/communication system using a Low Density Parity Check (LDPC) code. A weight-1 position sequence conversion procedure is performed on an initial parity check matrix. Shortening is applied on an information word. A codeword is generated by LDPC encoding the information word using a parity check matrix generated by performing the weight-1 position sequence conversion procedure. Puncturing is then applied to the codeword. | 07-12-2012 |
20120183003 | APPARATUS AND METHOD FOR PROVIDING COMPATIBILITY OF TRANSMISSION SIGNAL IN COMMUNICATION SYSTEM - Method and apparatus for transmitting and receiving a signal in a broadcasting communication system are provided. Data of an input stream is divided for transmission through a frame. A header that includes information about the input stream is constructed. The frame is constructed using the header and the divided data. | 07-19-2012 |
20120198306 | METHOD AND APPARATUS FOR TRANSMITTING AND RECEIVING IN COMMUNICATION/BROADCASTING SYSTEM - An apparatus and method are provided for transmitting and receiving in a communication/broadcasting system. The method includes generating a codeword including a first parity bit using a first parity-check matrix, generating an additional parity bit based on a second parity-check matrix, the second parity-check matrix being an extension of the first parity-check matrix, and transmitting the codeword and the additional parity bit. | 08-02-2012 |
20120236922 | DIGITAL BROADCASTING TRANSMITTER, DIGITAL BROADCASTING RECEIVER, AND METHOD FOR COMPOSING AND PROCESSING STREAMS THEREOF - Disclosed is a method of processing a stream of a digital broadcasting receiver. The method comprises: arranging at least one of new mobile data and known data in at least a portion of an existing mobile data region and in at least a portion of a normal data region, in a stream which includes the normal data region and the existing mobile data region; and composing a transmission stream where at least one of the new mobile data and the known data is arranged, and wherein the arranging combines a block of data arranged in the existing mobile data region and a block of the new mobile data in the stream, and performs serially concatenated convolution code (SCCC) coding on the combined blocks. | 09-20-2012 |
20120290887 | APPARATUS AND METHOD FOR TRANSMITTING AND RECEIVING DATA IN COMMUNICATION SYSTEM - An apparatus and a method for transmitting and receiving a signal in a communication system are provided. The method includes checking a type of the signal to be transmitted; determining a number of puncture bits according to the type of the signal; and puncturing an encoded signal to be transmitted according to the number of puncture bits. | 11-15-2012 |
20120307846 | DIGITAL BROADCAST TRANSMITTER AND DIGITAL BROADCAST RECEIVER, AND METHOD FOR PROCESSING STREAMS THEREOF - Provided is a digital broadcast transmitter including a MUX and an exciter, which construct streams including first service data and second service data that are different from each other. The exciter interleaves streams such that the first service data has a first body, a first head, and a first tail, the second service data has a second body, a second head, and a second tail, and the first head or the first tail is engaged with the second head or the second tail, at the interface between the first service data and the second service data, wherein at least a portion of the second service data is LDPC-coded or turbo-coded, and the rest of the second service data is TCM-coded. | 12-06-2012 |
20120317461 | APPARATUS AND METHOD FOR TRANSMITTING AND RECEIVING PACKET IN BROADCASTING AND COMMUNICATION SYSTEM - A method and an apparatus for transmitting and receiving a packet in a broadcasting and communication system are provided. The method and apparatus allows a receiver to recognize data in a packet lost due to data loss occurring in a network. To this end, Forward Error Correction (FEC) control-related information is generated, a packet including the generated FEC control-related information is generated, and the packet is transmitted. The FEC control-related information includes at least one of FEC configuration-related information and FEC encoding configuration-related information. | 12-13-2012 |
20120327306 | METHOD AND APPARATUS FOR TRANSMITTING AND RECEIVING DATA IN BROADCASTING SYSTEM - Methods and apparatus are provided for transmitting data in a broadcasting system. Input data is encoded by an encoder. A first demultiplexer generates first transmission symbols using the encoded data. The first transmission symbols are modulated, and the modulated first transmission symbols are transmitted. A second demultiplexer generates second transmission symbols using at least a portion of the encoded data. The second transmission symbols are modulated and the modulated second transmission symbols are transmitted. | 12-27-2012 |
20130051405 | DIGITAL BROADCAST TRANSMITTER, DIGITAL BROADCAST RECEIVER, AND METHOD FOR CONFIGURING AND PROCESSING STREAMS THEREOF - Provided are a digital broadcast transmitter, a digital broadcast receiver, a method for processing a stream of the transmitter, and a method for processing a stream of the receiver. The method of processing the stream of the transmitter includes: arranging second mobile data according to a predetermined mode within a stream that includes a first region allocated for first mobile data and a second region allocated for normal data; configuring the stream in which the normal data and the second mobile data are arranged; and encoding and interleaving the stream to output the stream as a transport stream. | 02-28-2013 |