Abstract: The present invention relates to a method and apparatus for transmitting and receiving data. A data transmission method from a sender terminal to a receiver terminal in a MIMO system using a variable frequency band according to one embodiment of the present invention comprises: repeatedly generating a signal field depending on a frequency band that is applied to the transmission of a data frame; generating a data field including the data; generating a data frame including the signal field and the data field; and transmitting the data frame to the receiver terminal. The present invention is advantageous in that a signal field which is transmitted together with the data being transmitted from the sender terminal to the receiver terminal in the MIMO system can be sent more efficiently.

Abstract: A method for detecting a multiple input multiple output (MIMO) signal in a wireless communication system is provided. The method includes: selecting from a first antenna each of the first candidate signal constellations in which a first path metric for at least one first survivor path is minimal; acquiring at least one second survivor path based on the first candidate signal constellations; updating a second survivor path so as to remove an effect on the second survivor path due to the first candidate signal constellations; selecting from a second antenna each of the second candidate signal constellations in which a second path metric for the at least one updated second survivor path is minimal; acquiring at least one final survivor path based on the second candidate signal constellations; and acquiring a transmitting symbol among the final survivor paths.

Abstract: A method for reducing power consumption in a wireless communication system includes: generating a descramble initial value by using at least some bits of identification information of an STA, which is known to an AP or base station and the STA; generating a first descramble sequence by using the generated descramble initial value and comparing at least some bits of the generated first descramble sequence with at least some bits of a service field of a currently-received signal; as the comparison result, when it is determined that the destination of the currently-received signal is not set to the STA, stopping the signal reception; and as the comparison result, when it is determined that the destination of the currently-received signal is set to the STA, generating a second descramble sequence by using the descramble initial value and descrambling the currently-received signal.

Abstract: Provided a method for simultaneously transmitting data frames to a plurality of STAs in a multi-user based wireless communication system. The method includes: requesting sounding or feedback for the plurality of STAs by using a first control information frame containing first group information; receiving responses to the sounding or feedback request; reconfiguring the plurality of STAs composing the first group into a plurality of second groups on the basis of the responses such that the sum of maximum transport streams of the respective STAs composing one group becomes equal to or less than the maximum number of streams transmitted by an AP; transmitting a second control information frame containing second group information on the respective second groups to the plurality of STAs composing the first group; and transmitting data frames by using the second group information.

Abstract: The present invention relates to a method and apparatus for transmitting and receiving data. A data transmission method from a sender terminal to a receiver terminal in a MIMO system using a variable frequency band according to one embodiment of the present invention comprises: repeatedly generating a signal field depending on a frequency band that is applied to the transmission of a data frame; generating a data field including the data; generating a data frame including the signal field and the data field; and transmitting the data frame to the receiver terminal. The present invention is advantageous in that a signal field which is transmitted together with the data being transmitted from the sender terminal to the receiver terminal in the MIMO system can be sent more efficiently.

Abstract: Provided are a transmitter and a method for transmitting a data block in a wireless communication system. The method comprises the following steps: encoding an information bit and generating a block coded with an NCBPSS bit; generating two sub-blocks by parsing the coded block; and transmitting the two sub-blocks to the transmitter. By preventing the bits that are contiguous to the encoding block from having continuous identical reliabilities on a signal constellation, the deterioration of the decoding performance of the transmitter can be prevented.

Abstract: Provided is a method for transmitting data frames to multiple STAs in a wireless communication system which divides a frequency band into frequency band segments to allocate. The method includes: setting a group by grouping a plurality of STAs; determining whether or not to separately allocate the frequency band segments to the STAs within the group; constructing a control frame containing a segment field, based on the determination result; and transmitting the constructed control frame through a common signal, and transmitting data frames.

Abstract: A method and apparatus of selecting N metrics among M metrics is provided. The apparatus determines M metrics P(i), where i=1, . . . , M. Each P(i) is represented by B bits. The apparatus determines N metrics among M metrics. The complexity for configuring the circuit is decreased, and the length of the critical path is reduced.

Abstract: Disclosed is an apparatus and method for transmitting/receiving data using a low-density parity check (LDPC) coding scheme in a communication system. The method includes generating a multi-user data packet containing data to be transmitted to a plurality of users, encoding the multi-user data packet as a BCC and an LDPC code, and transmitting the encoded multi-user data packet to the plurality of users. In the method, the encoding of the multi-user data packet encodes MPDU subframes corresponding to each of the plurality of users in the multi-user data packet as the LDPC code, and calculates information on a length in LDPC encoding, corresponding to the encoding of the multi-user data packet as the LDPC code.

Abstract: A data receiving method in a wireless LAN system using multiple channels includes: determining whether a difference value of signal levels of first and second access points is equal to or less than a preset value; transmitting an association request frame to the first and second access points according to the determination result; and receiving association response frames from the first and second access points.

Abstract: A switching apparatus in a wireless communication system using multi-channels includes: a first antenna unit configured to transmit and receive data of a first multi-channel among the multi-channels; a second antenna unit configured to transmit and receive data of a second multi-channel among the multi-channels; a first transceiver configured to receive the data from the first antenna unit and transmit the data to the first transceiver; and a selection unit configured to transmit an output of the second antenna unit to the first transceiver.

Abstract: Provided are a transmitter and a method for transmitting a data block in a wireless communication system. The method comprises the following steps: encoding an information bit and generating a block coded with an NCBPSS bit; generating two sub-blocks by parsing the coded block; and transmitting the two sub-blocks to the transmitter. By preventing the bits that are contiguous to the encoding block from having continuous identical reliabilities on a signal constellation, the deterioration of the decoding performance of the transmitter can be prevented.

Abstract: An apparatus and method for supporting access are provided. The method for supporting access in a wireless communication system includes: checking a plurality of stations (STA) which are to get access in a network and a plurality of access nodes of the respective STAs; determining the access priorities of the checked STAs and the priorities of the access nodes of the respective STAs; dividing a wireless resource and channel available in the network into multiple wireless resources and channels; and connecting the access nodes of the respective STAs to the multiple wireless resources and channels using a multi-channel media access control (MAC) protocol.

Abstract: The present invention relates to a method and apparatus for transceiving data. A method in which a transmitting terminal transmits data to a receiving terminal in a MIMO system according to one embodiment of the present invention comprises the following steps: generating a data field containing the data; generating a signal field containing information on the data field; generating a data frame containing the data field and the signal field; and transmitting the data frame to the receiving terminal. According to the present invention, an end of the frame being transmitted is accurately notified to the receiving terminal in a communication system in which the frame is transmitted using MIMO, thereby decoding the frame in a more efficient manner at the receiving terminal.

Abstract: Provided are an apparatus and method for providing a WLAN service using multiple channels. The wireless local area network (WLAN) service apparatus includes a service request receiver configured to receive service request information from a first wireless terminal accessed through a first channel, a data receiver configured to receive data from a first access point accessed through a second channel according to the service request information, a data transmitter configured to transmit the data to the first wireless terminal in a predetermined service area, and an access controller configured to control the first wireless terminal and the first access point to be accessed through different channels.

Abstract: Provided is a method and apparatus for receiving a signal for a MIMO system. The receiving apparatus includes: a QR decomposer for calculating a unitary matrix Q, an upper triangle matrix R, and a vector size for a received signal; a multiple dimension detector for calculating a first LLR for an output of the QR decomposer through multiple dimension detection; an inverse matrix and weight calculator for calculating an inverse matrix for the upper triangle matrix R and a weight; an interference remover for regenerating a symbol for a demodulated data stream using the fist LLR and removing interference from an output vector of the QR decomposer using the regenerated symbol; and a weight zero forcing unit for performing zero forcing on the interference removed output vector from the interference remover using the inverse matrix of the upper triangle matrix R and the weight and calculating a second LLR.

Abstract: Provided is a transmitter and a receiver for a high-throughput wireless communication system. The transmitter includes a baseband transmitter, a DIF transmitter, and a RF transmitter. The baseband transmitter performs a MAC protocol process on transmission signals and reception signals and processes the transmission signals by dividing an entire transmission band into n bands in a physical layer process of the transmission data, where n is a natural number. The DIF transmitter combines transmission signals of each band from the baseband transmitter and outputs m channel signals corresponding to a number of transmission antennas, where m is a natural number. The RF transmitter modulates each of the channel signals transferred from the DIF transmitter and transmits the modulated signals through m antennas.

Abstract: There is provided to a method for encoding an LDPC (Low Density Parity Check) code using the result of checking a previously specified parity, including the steps of: forming a parity bit check matrix having a dual diagonal structure consisting of (N-K) rows for check nodes and (N-K) columns on the basis of the H matrix; calculating the values of all the parity bits by inserting a given binary value in sub-blocks, with the parity bit check matrix formed on the H matrix; if the values of the parity bits are incorrect, checking the parity bit corresponding to the sub-block located in the last part of the H matrix; searching the parity bit parts where the parity bit check result is represented as “1”; performing an XOR operation in sub-blocks on the parity bit part obtained through a simultaneous equation between the parity bits of the searched parity bit parts and the parity bit parts; and determining the value of the parity bit satisfying the condition that the value obtained by multiplying the H matrix by a c

Abstract: Provided are a transmitter and a method for transmitting a data block in a wireless communication system. The method comprises the following steps: encoding an information bit and generating a block coded with an NCBPSS bit; generating two sub-blocks by parsing the coded block; and transmitting the two sub-blocks to the transmitter. By preventing the bits that are contiguous to the encoding block from having continuous identical reliabilities on a signal constellation, the deterioration of the decoding performance of the transmitter can be prevented.

Abstract: A method for detecting a multiple input multiple output (MIMO) signal in a wireless communication system is provided. The method includes: selecting from a first antenna each of the first candidate signal constellations in which a first path metric for at least one first survivor path is minimal; acquiring at least one second survivor path based on the first candidate signal constellations; updating a second survivor path so as to remove an effect on the second survivor path due to the first candidate signal constellations; selecting from a second antenna each of the second candidate signal constellations in which a second path metric for the at least one updated second survivor path is minimal; acquiring at least one final survivor path based on the second candidate signal constellations; and acquiring a transmitting symbol among the final survivor paths.