Abstract: Disclosed is an apparatus for receiving a signal in a communication system, which receives the signal, and decodes the received signal in a non-binary Low Density Parity Check (LDPC) decoding scheme, in which elements of a Galois field are expressed by an exponent representation, thereby minimizing the memory capacity required for a check node operation when the non-binary LDPC code is decoded.

Abstract: A calibration apparatus and a calibration method for multicell Multiple Input Multiple Output (MIMO) transmission in a multiple antenna system are provided. More particularly, an operating method of a Mobile Station (MS) for performing calibration for multicell MIMO transmission in a multiple antenna system includes negotiating a multi-Base Station (BS) joint processing with a BS, receiving a control message including information instructing multi-BS calibration for sounding based on the multi-BS joint processing, from the BS; when receiving the control message involving the multi-BS joint processing, generating a second sounding sequence by mapping estimated phases of downlink channels per subcarrier of BSs to a first sounding sequence allocated from the BS, and transmitting the second sounding sequence, including the phases of the downlink channels per subcarrier, over a sounding symbol interval with respect to each of the BSs involving the multi-BS joint processing.

Abstract: An apparatus and method for generating an RS SCH in a wireless communication system are provided, in which a base station checks a BS SCH sequence and a mask sequence, and generates an RS SCH sequence by XOR-operating the BS SCH sequence and the mask sequence.

Abstract: An apparatus is provided for transmitting a signal in a communication system using a Low Density Parity Check (LDPC) code. A controller determines a number of ‘0’s to be inserted in information data according to a first coding rate to be applied when generating the information data into an LDPC code, and determines the number of ‘0’s to be removed from the LDPC code. A ‘0’ inserter inserts ‘0s’ in the information data according to control of the controller. An LDPC encoder generates the LDPC code by encoding the ‘0’-inserted signal according to a first parity check matrix. A ‘0’ remover removes the inserted ‘0’s from the LDPC code.

Abstract: Provided are an apparatus and method for transmitting/receiving signal, supporting a variable coding rate, in a communication system. The method includes receiving an information vector, generating a child parity check matrix based on a parent parity check matrix according to a coding rate to be applied for generating a block Low Density Parity Check (LDPC) codeword using the information vector, and encoding the information vector into the block LDPC codeword according to the child parity check matrix.

Abstract: Disclosed is an apparatus and a method for transmitting/receiving a signal in a communication system, which generates an Affine Permutation Matrix-Low Density Parity Check (APM-LDPC) codeword by encoding an information vector in an APM-LDPC encoding scheme which is a preset structured LDPC encoding scheme, and detects the information vector by decoding the signal in a decoding scheme corresponding to the APM-LDPC encoding scheme, thereby making it possible to generate a Low Density Parity Check (LDPC) code in the form of maximizing a girth while minimizing complexity.

Abstract: An apparatus and method for reducing a Peak to Average Power Ratio (PAPR) of a Secondary Advanced (SA) preamble in a wireless communication system are provided. A method for transmitting an SA preamble includes determining an SA preamble, constructed in a unit of subblocks, according to a frequency band to be used for transmitting information, determining a sequence for reducing a PAPR of the SA preamble in consideration of at least one of a frequency band, a segment IDentifier (ID), and the number of antennas transmitting the SA preamble, updating the SA preamble using the determined sequence, and transmitting the updated SA preamble to a receive end.

Abstract: A method and apparatus is provided for receiving data in a receiver of a communication system. In the receiver, a first calculator calculates a Log Likelihood Ratio (LLR) value of data transmitted from a transmitter, a decoder performs iterative decoding on the transmitted data using the LLR value calculated by the first calculator. A second calculator determines whether there is an error in the decoded data by calculating an error of the data decoded by the decoder. A storage stores an LLR value of the decoded data according to the determination result of the second calculator. An adder adds up the LLR value calculated by the first calculator and the LLR value stored in the storage.

Abstract: Disclosed is a device and method for coding a block low density parity check (LDPC) code having a variable length. The a device and method include receiving an information word; and coding the information word into a block LDPC code according to a first parity check matrix or a second parity check matrix depending on a length to be applied when generating the information word into the block LDPC code.

Abstract: Disclosed is a method for supporting a handover in a broadband wireless access communication system which includes a mobile subscriber station, a serving base station currently providing service to the mobile subscriber station, and a plurality of adjacent base stations different from the serving base station, in which each of the base stations includes cells using subchannel bands different from each other, the method including establishing a set of base stations which currently provide wireless channels for data transmission/reception to the mobile subscriber station; classifying, by each base station, entire subchannels into a plurality of sets of subchannels; and allocating each of the sets of subchannels obtained by the classification to a PUSC (Partial Usage of Subchannels) subchannel area of each sector, wherein, every base stations included in an active set select an equal number of PUSC subchannels from among a PUSC subchannel area allocated to each of the base stations and allocate the selected PUSC

Abstract: A method for performing a Hybrid Automatic Repeat reQuest (HARQ) operation in a wireless mobile communication system that uses Frequency Division Duplex (FDD) or Time Division Duplex (TDD) frames each having a plurality of subframes for communication are provided, in which an HARQ timing including a transmission time of a data burst and a transmission time of an HARQ feedback, for DL HARQ is determined according to data burst assignment information transmitted in a #l DownLink (DL) subframe of a #i frame, and an HARQ operation is performed according to the determined HARQ timing. At least one frame index and at least one subframe index that represent the HARQ timing are determined by using l and i.

Abstract: An apparatus and method for transmitting/receiving an S-SCH in an Institute of Electrical and Electronics Engineers (IEEE) 802.16m wireless communication system are provided. A method for transmitting, by a transmitter, a Secondary Synchronization CHannel (S-SCH) in a communication system includes generating a sequence depending on a cell IDentification (ID), determining a subcarrier set comprising subcarriers to map the generated sequence, based on a Fast Fourier Transform (FFT) size and a segment ID, and mapping the generated sequence to the subcarriers of the determined subcarrier set.

Abstract: A Synchronization Channel (SCH) transmission method includes generating a Primary SCH (P-SCH) sequence according to supplementary information. The supplementary information includes at least one of Base Station (BS) type information, Fast Fourier Transform (FFT) size information, BandWidth (BW) information, group information, sector information, and carrier type information. The method also includes modulating the P-SCH sequence and mapping the modulated P-SCH sequence to subcarriers within a predefined subcarrier set. The subcarriers are included in the subcarrier set being spaced one subcarrier interval apart. The method further includes generating a P-SCH symbol by Orthogonal Frequency Division Multiplexing (OFDM)-modulating the P-SCH sequence mapped to the subcarriers, and transmitting the P-SCH symbol.

Abstract: A Base Station (BS) includes an apparatus is configured to reduce a MAP overhead in a broadband wireless communication system. The BS operation method for reducing an overhead in a broadband wireless communication system includes transmitting control information for initial transmission and changing first information among the control information transmitted at the initial transmission into second information needed at a retransmission time when there is a retransmission request for the initial transmission. The BS also transmits control information for retransmission including the second information.

Abstract: Disclosed is a method and apparatus for completely recovering received data with high reliability using LDPC codes without short-sized cycles in a digital communication system using an error-correcting code. The method includes performing exponent conversion of a predetermined number of exponent matrixes stored in advance in a memory so as to generate new exponent matrixes based on the exponent conversion, and generating new LDPC codes using the new exponent matrixes.

Abstract: A wireless communication system includes an apparatus and a method for supporting Hybrid Automatic Repeat Request. A transmitting method includes when an encoding packet is bigger than a maximum encoding packet size Nep_max, generating a first codeword by encoding the encoding packet at a mother code rate t; generating a second codeword by selecting [Nep_max/t]-sized code bits from the first codeword; and performing Hybrid Automatic Repeat reQuest (HARQ) using the second codeword.

Abstract: A apparatus and method for allocating synchronization acquisition sequence in a time domain and allocating a cell ID search sequence in a frequency domain. In a method for transmitting a synchronization signal of a base station in a wireless communication system, a binary frequency-domain preamble sequence predetermined for cell ID search and a binary time-domain preamble sequence predetermined for synchronization acquisition are used to determine a complex time-domain preamble sequence except the binary time-domain preamble sequence among the time-domain preamble sequences that are generated according to an Inverse Fast Fourier Transform (IFFT) operation on the binary frequency-domain preamble sequence. The complex time-domain preamble sequence and the binary time-domain preamble sequence are transmitted to a mobile station.

Abstract: An apparatus and method for generation of an M-length permutation sequence in a broadband wireless communication system are provided. Operations of a generator include splitting an L2-length seed value into a first part and a second part, determining coefficients of a generator polynomial using values of the first part and the second part, and calculating the permutation sequence using the generator polynomial.

Abstract: An apparatus and method for supporting Hybrid Automatic Repeat reQuest (HARQ) in a broadband wireless communication system are provided. A method of performing HARQ by a Mobile Station (MS) in a wireless communication system includes receiving a control message including resource allocation information, decoding the control message, if the decoding is successful, determining whether a previous control message is lost, and if the previous control message is lost, transmitting one of a null signal and a specific indicator through a response channel.

Abstract: An apparatus and method for generation of an M-length permutation sequence in a broadband wireless communication system are provided. Operations of a generator include splitting an L2-length seed value into a first part and a second part, determining coefficients of a generator polynomial using values of the first part and the second part, and calculating the permutation sequence using the generator polynomial.