| Patent application number | Description | Published |
|---|
| 20080225895 | Apparatus and Method for Generating Signal According to Ifdma, and Apparatus for Receiving Signal - A signal generation apparatus and signal receiving apparatus according to an Interleaved Frequency Division Multiple Access scheme is provided. The signal generation apparatus generates a plurality of complex symbols by digital-modulating a plurality of data symbols, and rotates the generated plurality of complex symbols in a plurality of each different phase angles. The signal generation apparatus generates a plurality of transmission symbols by repeating a plurality of rotated complex symbols at predetermined times, and rotating the repeatedly generated plurality of transmission chips in phase angles of an orthogonal phase sequence for the respective users. When the signal receiving apparatus receives the plurality of transmission symbols generated as described above, the maximum diversity gain may be obtained. | 09-18-2008 |
| 20080232500 | Soft Output Sphere Decoding Method - Provided is a soft output sphere decoding method for a MIMO system. The soft output sphere decoding method includes the steps of: detecting a maximum likelihood symbol nearest to a receiving signal; calculating a lattice point nearest to the receiving signal and having a symbol bit opposite to the detected maximum likelihood symbol for all bits of the receiving signal; and calculating a ratio between a distance from the receiving signal to the detected maximum likelihood symbol and a distance from the receiving signal to the calculated lattice points for each bit. | 09-25-2008 |
| 20080285677 | Apparatus and Method For Transmitting Signals With Multiple Antennas - An apparatus for transmitting signals with multiple antennas is disclosed. The multiple antenna transmission apparatus performs space-time encoding or space-frequency encoding, and cyclically delays the encoded symbol with a plurality of delay-values to generate a plurality of delayed symbols. The multiple antenna transmission apparatus transmits the plurality of delayed symbols to the channel through a plurality of antennas. By changing the number of space areas for encoding and the number of delay-values for delaying, the number of antennas for the multiple antenna transmission apparatus is easily expanded. | 11-20-2008 |
| 20080298225 | Transmitting Apparatus for Transmitting in a Multi-Carrier System Using Multiple Antennas and Receiving Apparatus in the Same System - A transmitting apparatus and receiving apparatus of a multi-carrier system using multiple antennas is proposed. An LCF encoder of the transmitting apparatus performs a liner precoding to input signals to be transmitted to a receiving apparatus using a liner complex matrix considering the number of multiple antennas and the number of subcarriers, and a subcarrier allocator respectively allocates a subcarrier to the signals liner-precoded by the LCF encoder. A transmitter respectively transmits the signals having a subcarrier allocated by the subcarrier allocator through the multiple antennas externally. A subcarrier de-allocator of a receiving apparatus extracts a liner-precoded signal by de-allocating a subcarrier allocated to the received signal. An LCF decoder outputs a bit reliability of the received signal to the liner-precoded signal extracted from the subcarrier de-allocator considering the number m of multiple antennas and the number n of subcarriers. A performance may be improved by using space diversity due to multiple antennas and a frequency diversity due to the OFDMA system, and a complexity may be reduced and a hard decision value of a performance similar to the maximum likelihood detection may be obtained by using a lattice reduction and a 2-branch Chase decoder. | 12-04-2008 |
| 20090022209 | TRANSMITTING APPARATUS USING SPREAD-SPECTRUM TRANSMISSION METHOD - The present invention relates to a transmitting apparatus using a spread-spectrum transmission scheme. The transmitting apparatus includes a precoder for preceding a data signal by performing a product operation between a first matrix and a diagonal matrix. The preceding outputs a signal responding to the input data by performing a product operation between the first matrix and the diagonal matrix. Such a transmitting apparatus obtains a maximum diversity gain. | 01-22-2009 |
| 20090202015 | TRANSMITTER HAVING FULL-DIVERSITY AND FULL-RATE, A LINEAR SPACE-TIME CODE GENERATING METHOD FOR THE TRANSMITTER, AND A MIMO SYSTEM USING SAME - 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. | 08-13-2009 |
| 20090252240 | TRANSMITTING APPARATUS AND METHOD, AND RECEIVING APPARATUS AND METHOD IN MULTPLE ANTENNA SYSTEM - Respective codewords of quantization codebooks corresponding to a number of data streams are selected based on channel information estimated by a received training symbol. A stream mode is selected among stream modes to determine a modulation method applied to each data stream. The data stream is detected by using the codeword corresponding to the quantization codebook of the data stream corresponding to the selected stream mode as a precode matrix, and the detected data stream is modulated. In this case, a receiving apparatus performs a feedback operation so that indexes of the selected stream mode and the codeword used as the precode matrix may be transmitted to the transmitting apparatus. The transmitting apparatus selects the number of transmitted data streams and the modulation method based on the transmitted index of feedback streams by the feedback operation. | 10-08-2009 |
| 20100118851 | APPARATUS AND METHOD FOR PROVIDING WLAN SERVICE USING MULTIPLE CHANNEL - 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. | 05-13-2010 |
| 20100142468 | APPARATUS AND METHOD FOR SUPPORTING ACCESS IN WIRELESS COMMUNICATION SYSTEM - 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. | 06-10-2010 |
| 20100162074 | APPARATUS AND METHOD FOR CODING QC-LDPC CODE - 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. | 06-24-2010 |
| 20100177656 | METHOD AND APPARATUS FOR TRANSMITTING AND RECEIVING WIRELESSLY PROVIDING HIGH CAPACITY SERVICE USING MULTIPLE ACCESS LINKS - 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. | 07-15-2010 |
| 20100266072 | METHOD AND APPARATUS FOR RECEIVING SIGNAL FOR MIMO SYSTEM - 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. | 10-21-2010 |
| 20100269011 | APPARATUS AND METHOD FOR DECODING LOW DENSITY PARITY CHECK CODE USING PROTOTYPE MATRIX - Provided is an apparatus and method for decoding a low density parity check (LDPC) code using a prototype matrix. The apparatus includes: a bit input unit for receiving a log likelihood ratio (LLR) value for an input bit; a check matrix processing unit for sequentially processing a parity check matrix for the received LLR value using a prototype parity check matrix through partial-parallel processing; and a bit processing unit for restoring the input bit by determining a bit level from the partial-parallel processed parity check matrix value. | 10-21-2010 |
| 20110150054 | SWITCHING APPARATUS AND METHOD FOR WIRELESS COMMUNICATION SYSTEM - 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. | 06-23-2011 |
