Patent application number | Description | Published |
20090135942 | APPARATUS AND METHOD FOR TRANSMITTING DATA USING MULTI-ANTENNA - Provided are an apparatus and method for transmitting data using a multi-antenna. The apparatus includes a transmission buffer selecting unit for selecting transmission buffer of an antenna group corresponding to characteristics of each aggregated Medium access control Protocol Data Units (MPDU) when a list of aggregated MPDUs to transmit is received; a data transmitting unit for generating a list of aggregated MPDUs to transmit with storage information of the aggregated MPDUs, transferring the generated list to the transmission buffer selecting unit and transmitting corresponding aggregated MPDUs through the selected transmission buffer; and a timing controlling unit for controlling a transmission timing of each aggregated MPDU. | 05-28-2009 |
20090141679 | METHOD FOR FORMING FRAME IN WIDEBAND WIRELESS COMMUNICATION SYSTEM USING MULTI-ANTENNA - A method for forming a frame in a wireless communication system is provided. In the method, a plurality of preamble symbols are disposed. Then, a signal symbol is disposed at a predetermined position among the plurality of preamble symbols. At least one of data symbols is disposed after the plurality of preamble symbols. | 06-04-2009 |
20090154334 | QR DECOMPOSITION APPARATUS AND METHOD FOR MIMO SYSTEM - 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. | 06-18-2009 |
20090154405 | MEDIUM ACCESS CONTROL METHOD AND DATA TRANSMISSION METHOD USING THE SAME IN WIRELESS LOCAL AREA NETWORK - Provided are a MAC method and a method for transmitting data using the same in a WLAN. The MAC method includes: transmitting a bandwidth scheduling report frame for informing information on downlinks and uplinks allocated to a terminal by including the bandwidth scheduling report frame in one of the downlinks where the bandwidth scheduling report frame includes a plurality of downlinks, a plurality of uplinks, and a plurality of short uplinks and the number of the plurality of downlinks is equal to the number of the plurality of uplinks; receiving a bandwidth request frame for requesting bandwidth allocation through one of the uplinks; and allocating a bandwidth to each of the terminals by an unit of the downlink and the uplink. | 06-18-2009 |
20090154427 | TRANSMITTER AND RECEIVER FOR HIGH THROUGHPUT WIRELESS COMMUNICATION SYSTEM USING MULTIPLE ANTENNA, METHOD THEREOF, AND DIGITAL INTERMEDIATE FREQUENCY TRANSMISSION SIGNAL PROCESSING METHOD FOR THE SAME - Provided are a transmitter and receiver for a high throughput wireless communication system using a multiple antenna, a method thereof, and a digital intermediate frequency (DIF) transmission signal processing method for the same. The transmitter, includes: a baseband transmitting unit for processing a transmission signal by performing a Media Access Control (MAC) protocol process on transmission data and dividing the transmission data into n band signals where n is a predetermined natural number in a physical layer process; a DIF transmitting unit for integrating transmission signals of each band transmitted from the baseband transmitting unit and outputting m channels where m is a predetermined natural number; and a Radio Frequency (RF) transmitting unit for modulating each channel signal transmitted from the DIF transmitting unit into an RF signal and emitting the signal through the multiple antenna. | 06-18-2009 |
20090154579 | QR DECOMPOSITION APPARATUS AND METHOD FOR MIMO SYSTEM - 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. | 06-18-2009 |
20090154586 | MIMO RECEIVER, QR DECOMPOSITION AND MULTI-DIMENSIONAL DETECTION USED IN THE MIMO RECEIVER - Provided are a receiver of a Multiple Input Multiple Output (MIMO) system, QR decomposition and multi-dimensional detection used in the receiver. The receiver includes: a QR decomposing unit for performing a QR decomposing operation in cycles 1 to n | 06-18-2009 |
20090154587 | MIMO ANTENNA RECEIVING APPARATUS AND RECEIVING METHOD - Provided is a reception apparatus and method of a Multiple Input Multiple Output (MIMO) system that receives a plurality of different data streams in a multiple cell environment. The reception apparatus for receiving a plurality of different data streams in a multiple input multiple output (MIMO) antenna system includes a data stream detector for detecting each data stream by removing interference between the different data streams while maintaining channel information; and a cochannel interference (CCI) remover for removing cochannel interference from each data stream detected in the data stream detector. The present invention can remove cochannel interference and increase channel capacity to thereby acquire both diversity gain and multiplexing gain. | 06-18-2009 |
20090154604 | MULTI-DIMENSIONAL DETECTOR FOR RECEIVER OF MIMO SYSTEM - 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 m | 06-18-2009 |
20090154608 | RECEIVING APPARATUS AND METHOD FOR MIMO SYSTEM - 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. | 06-18-2009 |
20090156148 | LINK ADAPTATION METHOD AND APPARATUS IN WIRELESS COMMUNICATION SYSTEM - 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. | 06-18-2009 |
20090158112 | METHOD FOR PRODUCING PARITY CHECK MATRIX FOR LOW COMPLEXITY AND HIGH SPEED DECODING, AND APPARATUS AND METHOD FOR CODING LOW DENSITY PARITY CHECK CODE USING THE SAME - 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. | 06-18-2009 |
20090158113 | APPARATUS AND METHOD FOR ENCODING LDPC CODE USING MESSAGE PASSING ALGORITHM - 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. | 06-18-2009 |
20090158121 | APPARATUS AND METHOD FOR DECODING LDPC CODE BASED ON PROTOTYPE PARITY CHECK MATRIXES - 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. | 06-18-2009 |
20090161808 | APPARATUS AND METHOD FOR DETECTING RECEPTION SIGNAL SYMBOL SYNCHRONIZATION IN WIRELESS COMMUNICATION SYSTEM - Provided is an apparatus and method for detecting reception signal symbol synchronization in a wireless communication system. The method, includes: calculating a channel power value in each of multiple antennas; selecting and averaging at least 2 channel power values; compensating carrier frequency offset for an average value; and determining a symbol boundary of a reception signal according to the size of the average value compensating the carrier frequency offset. | 06-25-2009 |
20090164540 | APPARATUS AND METHOD FOR UPDATING CHECK NODE OF LOW DENSITY PARITY CHECK CODE - 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. | 06-25-2009 |
20090190686 | APPARATUS AND METHOD FOR CHANNEL ESTIMATION IN MIMO SYSTEMS - Provided are a preamble structure and a channel estimation algorithm thereof. A communication method for a transmitter for channel estimation in a Multiple Input Multiple Output (MIMO) wireless communication system having N receiving antennas, includes generating a preamble interval having a short training field that includes a predetermined pattern iterated N times on a time domain and is used for compensating for a carrier frequency offset, and transmitting a packet having the preamble interval. | 07-30-2009 |
20100002806 | APPARATUS FOR RECEIVING SIGNALS IN OFDM COMMUNICATION SYSTEM HAVING MULTIPLE ANTENNAS AND METHOD THEREOF - Provided are an apparatus for receiving signals in an OFDM communication system using multiple transmission/reception antennas and a method thereof. The method includes modulating a predetermined part of a data stream based on a multi-dimensional reception procedure to generate a first modulated data stream; regenerating a symbol corresponding to the modulated data stream; eliminating the regenerated symbol from a remained data stream; modulating the eliminated data stream to generate a second modulated data stream; and outputting an output signal obtained by serializing the first modulated data stream and the second modulated data stream. | 01-07-2010 |
20100031116 | METHOD FOR ENCODING LOW DENSITY PARITY CHECK CODES USING RESULT OF CHECKING PREVIOUSLY SPECIFIED PARITY BITS - 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 code word vector. | 02-04-2010 |
20100142663 | APPARATUS AND METHOD FOR RECEIVING SIGNAL IN WIRELESS COMMUNICATION SYSTEM USING MULTI ANTENNA - Provided are apparatus and method for receiving signals in a wireless communication system. A receiving apparatus including a plurality of variable gain amplifier units configured to respectively control the gains of radio frequency (RF) signals received respectively through a plurality of antennas, and a plurality of analog-to-digital converters configured to respectively convert the output signals of the respective variable gain amplifiers into digital signals, includes: an automatic gain controller configured to calculate the gain values of the respective gain control amplifier units by receiving the digital signals outputted from the respective analog-to-digital converters, select the minimum gain value among the calculated gain control values, and calculate the differences between the minimum gain value and the other gain values; and a noise matching amplifier configured to attenuate the digital signals outputted from the respective analog-to-digital converters according to the calculated difference values. | 06-10-2010 |
20100150257 | APPARATUS AND METHOD FOR ESTIMATING TIMING OFFSET IN A WIRELESS COMMUNICATION SYSTEM - A method for estimating timing offset in an OFDM wireless communication system using preamble and pilot includes: estimating a carrier offset by using preamble included in a currently received OFDM packet and estimating a first timing offset based on the estimated carrier offset to thereby produce a first timing offset estimation value; estimating a second timing offset to thereby produce a second timing offset estimation value by transforming the OFDM packet into signals of frequency domain and using a pilot signal of the frequency-domain signals; checking a channel condition based on packet error information of a previously received packet to thereby produce error condition information, and selecting one between the first timing offset estimation value and the second timing offset estimation value based on the error condition information; and compensating data signals for timing offset among the frequency-domain signals the based on the selected timing offset estimation value. | 06-17-2010 |
20100150278 | RECEIVER FOR HIGH-SPEED WIRELESS COMMUNICATION SYSTEM AND CONTROL METHOD THEREOF - An apparatus for reducing power consumption of a receiver in a high-speed wireless communication system and a control method thereof are provided. The apparatus for processing a signal in a receiver of a wireless communication system includes a carrier sensor configured to sense a carrier used in the wireless communication system, a decoder configured to decode the detected carrier signal to a signal and data, and a controller configured to control supplying power and a clock only to the carrier sensor during carrier sensing, and supplying power and a clock to an overall receiver when a carrier is sensed. | 06-17-2010 |
20100157893 | APPARATUS AND METHOD FOR TRANSMITTING DATA IN WIRELESS COMMUNICATION SYSTEM - Disclosed is an apparatus and method for transmitting data in a wireless communication system. The apparatus for transmitting a packet data in a wireless communication system includes a Media Access Control (MAC) layer for determining the number of the number of preambles to be inserted based on a feed-back reply signal from a receiver, and generating a multi-preamble aggregation packet by inserting the determined number of preambles into packets received from an upper layer and a physical layer for forming the multi-preamble aggregation packet generated in a data processing unit, by using a physical layer packet, and transmitting the formed multi-preamble aggregation packet. | 06-24-2010 |
20100260246 | TRANSMITTER AND RECEIVER FOR GIGA-BPS HIGH-THROUGHPUT WIRELESS COMMUNICATION SYSTEM WITH MULTIPLE ANTENNAS AND MULTIPLE BANDS - 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. | 10-14-2010 |