Abstract: In a cellar system providing various packet services, sleep mode operation of a terminal in an idle state is controlled. The cellular system determines a discontinuous receiving (DRX) period according to a QoS of a packet service provided to the terminal, and runs the sleep mode according to the determined DRX period. The cellular system runs the sleep mode divided into shallow sleep duration and deep sleep duration. With this manner, a paging delay to the terminal and a power consumption of the terminal may be reduced.

Abstract: In a cellular system in which OFDM is used, a forward link synchronization channel, a common pilot channel structure, an initial cell searching method of a mobile station, and an adjacent cell searching method for handover are required. A method of transmitting a forward synchronization signal in a wireless communication system according to the present invention includes generating a frame comprised of a plurality of sync blocks; and transmitting the frame through a forward link, wherein the frame comprises primary synchronization channel sequences which provide timing information of the sync blocks and a plurality of secondary synchronization channel sequences which provide timing information of the frame, wherein a cell identifier is specified by a combination of the primary synchronization channel sequence and a hopping code word specified by the plurality of the secondary synchronization channel sequences. Therefore, the cell searching time can be efficiently reduced in an OFDM system.

Abstract: A method of and an apparatus therefor searching a cell in a mobile station of a communication system in which a plurality of cells are grouped into a plurality of cell groups, and each cell group includes at least two cells. The method includes detecting a primary synchronization signal and a secondary synchronization signal from a received signal, and identifying a cell based on a combination of the primary synchronization signal and the secondary synchronization signal. The secondary synchronization signal is related to the cell group to which the mobile station belongs and the primary synchronization signal is related to the cell to which the mobile station belongs within the cell group.

Abstract: A group service providing method and apparatus suitable for use in a wireless communication system. A group registration method for providing a group service to a master terminal and a slave terminal, the group registration method may comprise receiving and storing subscriber profile information of the master terminal from an associated communication network server in response to a group service registration request from the master terminal; generating a group related to the group service registration request and a group key corresponding to the generated group and transmitting to the master terminal a group generation completion message including the group key; receiving and storing subscriber profile information of the slave terminal dependent on the master terminal from the communication network server; and transmitting the group key to the slave terminal with reference to the subscriber profile information of the slave terminal.

Abstract: A method for establishing a communication link of a first communication device by selecting a target from a screen includes: selecting a second communication device for establishing a communication link on a screen of the first communication device; transmitting a request for a communication link including information regarding the establishment of a link on the basis of the first communication device required for establishing a communication link to the selected second communication device; receiving a communication link response including information regarding the establishment of a communication link on the basis of the second communication device required for establishing a communication link from the second communication device; and establishing a communication link between the first communication device and the second communication device by using the information regarding the establishment of a link on the basis of the first communication device and the information regarding the establishment of a link

Abstract: Provided is method of forming a signal in a wireless communication system in which a plurality of terminals commonly use a resource in the time domain and the frequency domain. The method includes multiplying a signal to be transmitted by a frequency domain orthogonal code symbol corresponding to a first cyclic shift index in a first slot to be transmitted to a base station, wherein the multiplying is performed by a first terminal and a second terminal; and multiplying information to be transmitted by a frequency domain orthogonal code symbol corresponding to a second cyclic index that is different from the first cyclic index of the first slot to be transmitted to the base station, in a second slot, wherein the multiplying is performed by the first terminal and the second terminal.

Abstract: An apparatus for generating a downlink signal and a cell search apparatus are disclosed. An apparatus for generating a downlink signal generates a downlink signal by one unique cell identification code group and a plurality of frame synchronization identification sequences, generates a downlink signal by a plurality of unique cell identification code groups and a plurality of frame synchronization identification sequences, or generates a downlink signal by a plurality of unique cell identification code groups and one frame synchronization identification sequence. A cell search apparatus obtains frame synchronization and identifies cells through a frame synchronization identification sequence and a unique cell identification code group.

Abstract: Provided is a method for transmitting and receiving multimedia broadcast multicast service (MBMS) data in a packet based cellular system.

Abstract: The present invention relates to a method of generating a downlink frame. The method of generating the downlink frame includes generating a first sequence and a second sequence for identifying cell groups; generating a first scrambling sequence and a second scrambling sequence that are one-to-two mapped to the sequence number of the primary synchronization signal; scrambling the first sequence with the first scrambling sequence and scrambling the second sequence with the second scrambling sequence; and generating a secondary synchronization signal including the scrambled first sequence and second sequence and mapping the secondary synchronization signal to a frequency domain.

Abstract: Provided is a Multimedia Broadcast Multicast Service (MBMS); and, more particularly, a data transmission/receiving method in a multimedia broadcast multicast service system, and an apparatus thereof. The data transmitting method in the MBMS system includes the step of checking a terminal receiving data provided from the MBMS and the step of determining whether there is error report feedback on retransmission of the data according to the number of the detected terminals.

Abstract: A method of generating a parity-check matrix of a low density parity-check (LDPC) code with a variable information length and a variable code rate, an encoding/decoding method, and an apparatus using the same are provided. The method of generating a parity-check matrix of an LDPC code includes: a first parity-check matrix generation process of generating a first parity-check matrix constructed with a first information block and a parity block; and an m-th parity-check matrix generation process of generating an m-th parity-check matrix by an m-th information block to a generated (m?1)-th parity-check matrix (1<m?M, where M is a natural number equal to or greater than two). Accordingly, it is possible to provide an LDPC code with a variable information length and a variable code rate which has a low complexity for encoding/decoding and a high quality of correction and detection of errors.

Abstract: Disclosed is a method and apparatus for RA in a cellular system. The RA in the cellular system includes receiving an RA preamble from a terminal for RA, transmitting, to the terminal, an RA response message including a sequence of the received RA preamble and uplink resource information of the terminal and overload state information with respect to the RA, receiving control information generated based on the RA response message from the terminal through the uplink resource information, and transmitting control response information with respect to the received control information.

Abstract: The present invention relates to an orthogonal frequency division multiplexing wireless local area network (LAN) transmitting/receiving system for providing expanded service coverage, and a method thereof. A first OFDM modulation is performed for an even-numbered time, and a second OFDM modulation is performed for an odd-numbered time. A transmitting frame including a plurality of signal fields according to the first and second OFDM modulation is transmitted. The receiving system determines whether a signal field is repeatedly generated in the frame. If the signal field is not repeatedly generated, corresponding demodulation is performed. If repeatedly performed, the signal field is demodulated by using first bit allocation information and second bit allocation information having a ½ value of the first bit allocation information. A data field is demodulated according to the demodulated signal field.

Abstract: The present invention provides a method for resource allocation in a wireless communication system. In the method for resource allocation, a scheduler of a base station decides on a modulation scheme and an encoding scheme according to channel quality information (CQI), and decides on a number of allocated resource blocks according to transmission data size referring to a table of resource block allocation. The table of resource block allocation presents a number of allocated resource blocks and a number of transmission bits according to the number of allocated resource blocks.

Abstract: A digital system design method uses a higher programming language. In order to realize a digital system, an algorithm is verified based on a program written by the higher programming language and a program is programmed considering the higher programming language-hardware characteristics before the program is written in the lower programming language, and thus conversion into the lower programming language may be easily performed.

Abstract: Provided is a method of efficiently transmitting an acknowledgement/negative acknowledgement (ACK/NACK) bit supporting hybrid automatic repeat request (HARQ) in a wireless communication system supporting multi-user multi-input and multi-output (MIMO). The method transmits the same downlink code and in-phase/quadrature (I/Q) multiplexed ACK/NACK bit to two mobile stations using the same uplink resource block. Accordingly, the method can efficiently transmit the ACK/NACK bit for multi-user MIMO and efficiently use downlink radio resources.

Abstract: When a plurality of terminals share the same resources in a wireless communication system, and when control information such as acknowledgement/negative acknowledgement (ACK/NAK) information or scheduling information is transmitted, a method of efficiently performing code division multiplexing (CDM) is required to distinguish the plurality of terminals. In particular, it is necessary to develop a method by which a code sequence of CDM can be selected and used according to each cell condition. Provided is a method of forming a signal in a wireless communication system in which a plurality of terminals commonly share frequency and time resources. The method includes the operations of receiving condition information in a cell; selecting one of a plurality of time domain orthogonal sequences having different lengths, according to the condition information; and allocating the selected time domain orthogonal sequence to a control signal symbol block.

Abstract: Provided is a method and apparatus for discontinuously transmitting/receiving packets for low-power consumption of a terminal in a cellular system for packet transmission. The present research provides a method and apparatus that can perform a low-power consuming operation when a terminal is in active state in a cellular system. The method for discontinuously transmitting/receiving packet data to reduce power consumption of a terminal in a cellular system, including a) establishing discontinuous reception/transmission (DRX/DTX) parameters including discontinuous DRX/DTX cycle information for terminals operating in a transmission suspension mode, which is a sub-state of an active state; and b) performing DRX/DTX based on the DRX/DTX parameters in the terminals operating in the transmission suspension mode.

Abstract: Provided is a method of forming a signal in a wireless communication system in which a plurality of terminals commonly use time and frequency resources for efficient code hopping. The method includes allocating the same frequency-axis sequence and different time-axis sequences to a plurality of terminals by using a resource index according to a first slot in the first slot; and allocating different frequency-axis sequences and different time-axis sequences to the plurality of terminals by using a resource index according to a second slot in the second slot.

Abstract: Provided are a channel estimation method and apparatus in mobile communication system having dispersed pilot. The channel estimation apparatus includes an entire band channel estimation unit and an edge channel estimation unit. The entire band channel estimation unit performs channel estimation on an entire frequency band. The edge channel estimation unit performs channel estimation on an edge region. By separately performing the gating operation of the entire band channel estimation unit and the gating operation of the edge channel estimation unit, a channel frequency response is more accurately calculated even in an edge region.