摘要:
Provided are a receiving apparatus for a multiple input multiple output (MIMO) system and a method thereof. The receiving apparatus includes a QR decomposing unit for calculating a single (Q) matrix vector and an upper triangle (R) matrix vector for a receiving signal vector; a first symbol estimation unit for estimating predetermined symbols using the calculated Q matrix vector and R matrix vector; a log likelihood ratio (LLR) calculating unit for calculating log likelihood ratios of unit bits for the estimated symbols; an interference removing unit for receiving a decoded signal that is decided using the calculated log likelihood ratios and removing interference from the receiving signal vector; and a second symbol estimation unit for linearly estimating remaining symbols for the interference removed signal.
摘要:
Provided is a QR decomposition apparatus and method that can reduce the number of computers by sharing hardware in an MIMO system employing OFDM technology to simplify a structure of hardware. The QR decomposition apparatus includes a norm multiplier for calculating a norm; a Q column multiplier for calculating a column value of a unitary Q matrix to thereby produce a Q matrix vector; a first storage for storing the Q matrix vector calculated in the Q column multiplier; an R row multiplier for calculating a value of an upper triangular R matrix by multiplying the Q matrix vector by a reception signal vector; and a Q update multiplier for receiving the reception signal vector and an output of the R row multiplier, calculating an Q update value through an accumulation operation, and providing the Q update value to the Q column multiplier to calculate a next Q matrix vector.
摘要:
Provided is an apparatus and method for encoding a Low Density Parity Check (LDPC) code using a message passing algorithm. The apparatus, includes: a parity calculating unit for operating a check node value on an input bit and a predetermined parity bit according to the message passing algorithm and calculating a parity bit; a parity correcting unit for correcting the calculated parity bit according to a parity check result of the calculated parity bit; and an output transform unit for combining the input bit and the corrected parity bit.
摘要:
The present invention relates to a method and an apparatus for transmitting control and training symbols to improve transmission efficiency in a multi-user wireless communication system. The method for transmitting the control and training symbols in the multi-user wireless communication system according to one embodiment of the present invention comprises the steps of: determining whether a required transmission rate of each data can be satisfied through channel estimation in each of terminals when different data are simultaneously transmitted to each of the terminals; and transmitting a data frame to each of the terminals, the data frame being composed to discriminate the control and training symbols in each of the terminals using a combination of time, frequency, and code area when the required transmission rate of each data is not satisfied according to the determined result.
摘要:
The apparatus includes a radio frequency (RF) unit configured to arrange a plurality of symbols received through an antenna at a frequency domain, an analog to digital (AD) converter configured to converts the plurality of symbols arranged at the frequency domain to digital symbols, a fast Fourier transform (FFT) unit configured to transform the digital symbols through a fast Fourier transform scheme, a compensator configured to compensate a gain mismatch between an I-channel and a Q-channel of the transformed digital symbols, a mapping unit configured to the compensated digital symbols to a constellation diagram, and a detector configured to correlate the mapped symbols, extract correlation results, and detect a high throughput (HT) signal using the extracted correlation results.
摘要:
An association supporting apparatus in a wireless communication system includes: a transmission/reception unit configured to scan associable access points (APs) among a plurality of APs existing in a plurality of station (STA) wireless networks, and receive state information from the scanned APs; a calculation unit configured to calculate transmit opportunity (TXOP) periods with respect to the APs by using the received state information of the APs; and a determination unit configured to determine a predetermined AP among the plurality of scanned APs, considering usable power levels of the APs and the number of associable STAs during the calculated TXOP periods.
摘要:
Provided are a QR decomposition apparatus and method for a MIMO system. The QR decomposition apparatus includes: a norm calculator for calculating a vector size norm for a channel input; a Q column calculator for calculating a column value of a unitary matrix Q by multiplying a delayed channel input with √{square root over (norm)}; an R row calculator for receiving the delayed channel input, the output of the Q column calculator, and 1/√{square root over (norm)}, and calculating a row value of an upper triangular matrix R; a Q update calculator for receiving the delayed channel input, the output of the R row calculator, and a delayed output of the Q column calculator, and calculating a Q update matrix value; and a norm update calculator for receiving a delayed output of the norm calculator and an output of the R row calculator, and outputting a norm update matrix value.
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:
Provided is an apparatus and method for decoding a Low Density Parity Check (LDPC) code based on prototype parity check matrixes. The apparatus, includes: a parity check matrix selecting means for determining multiple prototype parity check matrixes according to a sub-matrix size and a parallelization figure for processing the parity check matrix; a bit input means for receiving a log likelihood probability value for input bit according to the sub-matrix size and the parallelization figure; a check matrix process means for sequentially performing a partial parallel process on the parity check matrix based on the received log likelihood probability value and the determined multiple prototype parity check matrixes; and a bit process means for determining a bit level based on the partial-parallel processed parity check matrix value and recovering the input bit according to the sub-matrix size and the parallelization figure.
摘要:
Provided is a link adaptation method and apparatus in wireless communication system. The method, includes: amplifying a received signal; converting the amplified signal into a digital signal; calculating digital signal strength; and calculating the received signal strength based on the digital signal strength and a gain of said amplifying a received signal.