摘要:
A space-time code has a codeword matrix. The codeword matrix is a square matrix with dimension equal to the number of the transmit antennas, wherein a row of the codeword matrix represents combined signals transmitted by each transmit antenna and a column of the codeword matrix represents timeslots of the number of the transmit antennas. Signals are transmitted through the rows of the number of spatial multiplexing rate, in each column of the matrix. Further, the symbols of the number of the transmit antennas are combined by way of utilizing complex weights, in each row of the matrix. With this space-time code, a delay is minimized, so that change of channels can be managed efficiently. Also, the space-time code has minimum number of data symbols, and thus its complexity is minimized.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
Provided are a multi-dimensional detector for a receiver of an MIMO system and a method thereof. The multi-dimensional detector includes a first symbol detecting unit for calculating symbol distance values using an upper triangular matrix (R) obtained from QR decomposition to detect an mth symbol; a symbol deciding unit for deciding a symbol having a minimum distance value among the calculated symbol distance values from the first symbol detecting unit; and a second symbol detecting unit for calculating symbol distance values using an updated received signal y and the upper triangular matrix R to detect a (m−1)th symbol.
摘要:
A method for transmitting, by a transmitting terminal, data to a receiving terminal in a wireless communication system includes: generating a first detection field including symbols modulated by using a BPSK data tone; generating a second detection field including symbols modulated such that an even numbered subcarrier and an odd numbered subcarrier have a phase difference of 90 degrees; generating a data packet including the first detection field, the second detection field, and the data; and transmitting the data packet.
摘要:
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.
摘要:
Provided are a method for producing a parity check matrix for low complexity and high speed decoding, and an apparatus and method for coding a Low Density Parity Check (LDPC) code using the same. The method includes: calculating a cyclic shift value of a subblock to a matrix; and when the calculated cyclic shift values of the subblock are arrayed in the matrix, producing a parity check matrix by arraying the cyclic shift values of the subblock except ‘0 matrix’ without duplication to any one column.
摘要:
A high-speed quasi-cyclic low density parity check (QC-LDPC) coding apparatus for coding inputted information into a generator matrix having a dual diagonal matrix format includes: a parity bit generation unit configured to generate an arbitrary parity bit; a temporary parity bit generation unit configured to constitute the inputted information with circulants, and shift and combine the respective circulants at each row to generate a temporary parity bit; a corrected bit generation unit configured to generate corrected bits of parity bits by using an output of the temporary parity bit generation unit; and a parity bit correction unit configured to correct the temporary parity bit by reflecting an output of the corrected bit generation unit to the output of the temporary parity bit generation unit.
摘要:
Provided is an apparatus and method for updating a check node of a LDPC code at a high speed. The apparatus includes: a minimum value calculating unit for calculating a first minimum value of an input bit by sequentially calculating each bit of the first minimum value, and calculating a second minimum value using the calculated first minimum value; a node minimum value calculating unit for performing row splitting the calculated first and second minimum values by a check node and calculating a first minimum value and a second minimum value of each of the row-split nodes; and a minimum value deciding unit for deciding one of the calculated first and second minimum values of each of the row-split nodes as a minimum value corresponding to each degree of the input bit.