Abstract: 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. A shift region including a number of coded bits is set. The coded bits are rearranged 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. The rearranged coded bits are mapped 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.

Abstract: 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: generating a stream in which a plurality of slots of different formats is consecutively arranged; and encoding and interleaving the generated stream, and outputting the encoded and interleaved stream as a transport stream, wherein the generating the stream includes arranging at least one of second mobile data, training data, and dummy data in an orphan region generated according to a difference of the formats between consecutive slots of the plurality of slots.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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 (p1) using the low density parity check matrix, generating a second parity bit vector (p2), performing L-parallel iterative accumulation encoding on the first parity bit vector, and generating a codeword vector c=(s,p1,p2) including an information word vector and the first and second parity bit vectors. The communication method and apparatus herein provides an efficient encoding algorithm using the trade-off relationship between a circuit implementation and operation and delay complexities.

Abstract: 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.

Abstract: 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.

Abstract: An apparatus and method for supporting both a receiver using a single antenna and a receiver using multiple antennas in a Multiple Input Multiple Output (MIMO) wireless communication system are provided. The apparatus and method in a MIMO wireless communication system include a first synthesizer for generating a first Transmit (Tx) signal by adding a first signal and a second signal, a second synthesizer for generating a second Tx signal by subtracting the second signal from the first signal and a plurality of transmitting units for transmitting the first Tx signal and the second Tx signal through corresponding antennas. Accordingly, receivers having either a single antenna or multiple antennas may be employed in the same communication system.

Abstract: An apparatus and method for encoding a channel in a communication system using a Low-Density Parity-Check (LDPC) code. The method includes determining a number of parity bits to be subjected to puncturing; dividing the parity bits at predetermined intervals, and determining a number of puncturing bits, which are subjected to puncturing within the predetermined intervals; determining positions of puncturing parity bits corresponding to the determined number of puncturing bits; and repeatedly performing puncturing on the puncturing parity bits corresponding to the determined positions at the predetermined intervals. The predetermined intervals are determined by dividing a length of parity bits by a length of one column group in a parity-check matrix.

Abstract: 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.

Abstract: A method for encoding a channel in a communication system using a Low-Density Parity-Check (LDPC) code is provided. The method includes determining a number of parity bits for puncturing; dividing the parity bits at predetermined intervals, and determining a number of puncturing parity bits, which are subjected to puncturing within the predetermined intervals; determining a modulation scheme; determining positions of puncturing parity bits corresponding to the determined number of the puncturing parity bits within the predetermined intervals according to the modulation scheme; repeatedly performing puncturing on puncturing parity bits corresponding to the determined positions at the predetermined intervals; and transmitting remaining bits except for the punctured bits according to the modulation scheme.

Abstract: A method and apparatus for generating Low-Density Parity Check (LDPC) codes of various block lengths from a structured LDPC code in a communication system is provided. To support various block lengths, predefined rules are applied to a parity check matrix of an LDPC code, and then shortening is selectively applied to the parity check matrix. Subsequently, if information data bits are input, the input data information bits are encoded into an LDPC codeword by using the parity check matrix according to a preset encoding scheme, and then the encoded LDPC codeword is transmitted after puncturing is selectively applied.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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).

Abstract: Disclosed are a scanning apparatus, a mobile apparatus, and a scan job performing method thereof. The scan job performing method includes discovering at least one mobile apparatus supporting the scan-to-mobile function by using multicasting by the scanning apparatus, receiving information on at least one discovered mobile apparatus, setting a connection between the scanning apparatus and the mobile apparatus by using the received information of the mobile apparatus, and transmitting a scan image generated by the scanning apparatus to the mobile apparatus. With this configuration, authentication and connection between the scanning apparatus and the mobile apparatus are set by multicasting to thereby improve user's convenience.