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 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.
摘要:
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.
摘要:
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.
摘要:
An apparatus and method for updating a check node of a low-density parity check (LDPC) code in order to decode the LDPC code are provided. The method includes the operations of: (a) obtaining a first bit of a first minimum value among input values, the number of input values being equal to the number of degrees of the check node, by performing an AND operation on first bits of the input values, the first bits being most significant bits of the input values; (b) obtaining result values by switching and sequentially performing an XOR operation and an OR operation on the first bit of the first minimum value and each of the first bits of the input values; and (c) performing operations (a) and (b) on the result values set as input values and performing operations (a) and (b) a number of times corresponding to the number of bits of each input value, that is, repeating until last bits are set as input values, to thereby obtain the first minimum value, the last bits being least significant bits of the input values. Accordingly, the complexity of hardware is reduced, and super high-speed processing is possible.
摘要:
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.
摘要:
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.
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:
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:
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.