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Jae Hoon Chung, Anyang-Si KR

Jae Hoon Chung, Anyang-Si KR

Patent application numberDescriptionPublished
20090059844METHOD OF TRANSMITTING DATA IN MULTIPLE ANTENNA SYSTEM - A method of transmitting data in a wireless communication system comprises receiving feedback data on an uplink data channel, the feedback data comprising a precoding matrix indicator (PMI), wherein the value of the PMI corresponds to an index in a codebook, transmitting a precoding scheme for downlink data on a downlink control channel, wherein the preceding scheme is determined as one of at least two of a transmit diversity irrespective of the received PMI, an acknowledgement indicating preceding according to the received PMI and a new PMI indicating that it is used in precoding downlink data to be transmitted, and transmitting the downlink data on a downlink data channel after applying precoding according to the determined preceding scheme.03-05-2009
20090088148WIRELESS COMMUNICATION SYSTEM FOR MONITORING PHYSICAL DOWNLINK CONTROL CHANNEL - A method of monitoring a physical downlink control channel (PDCCH) in a wireless communication system is provided. A user equipment monitors a set of PDCCH candidates for a search space in a subframe. The search space includes a common search space monitored by all user equipments in a cell and a UE-specific search space monitored by at least one UE in the cell.04-02-2009
20090190528METHOD FOR TRANSMITTING AND RECEIVING CHANNEL STATE INFORMATION PERIODICALLY OR APERIODICALLY - A method for transmitting and receiving channel state information (CSI) periodically and aperiodically is disclosed. The method for aperiodically transmitting channel state information (CSI) by a terminal includes receiving an indicator requesting a channel state information report of a downlink channel from a base station over a downlink control channel, and aperiodically transmitting the channel state information (CSI) to the base station over a physical uplink shared channel (PUSCH) upon receiving the indicator from the base station.07-30-2009
20090238091MONITORING CONTROL CHANNEL IN WIRELESS COMMUNICATION SYSTEM - A method and apparatus of monitoring a physical downlink control channel (PDCCH) is disclosed. A starting location of a search space in a control region of a subframe k is acquired. The search space is defined by a set of PDCCHs at each aggregation level. The set of PDCCHs from the starting location in the search space at the each aggregation level is monitored. The starting location is defined by the multiple of the aggregation level in the control region.09-24-2009
20090245410Method for transmitting signals for reducing feedback overhead and method for transmitting feedback information for the same - A method for transmitting signals to reduce feedback overhead and a method for transmitting feedback information for the same are described. In transmitting signals through precoding, different codebook subsets are used in an open-loop transmission mode and a closed-loop transmission mode, thereby reducing feedback overhead. In this case, it is assumed that the codebook subsets for the respective transmission modes are optimized according to each transmission mode.10-01-2009
20090262848METHOD OF DESIGNING A MULTIPLEXING STRUCTURE FOR RESOURCE ALLOCATION TO SUPPORT LEGACY SYSTEM - New multiplexing UL structures for supporting legacy system are provided. A 16m system of diversity mode can be multiplexed with 16e system in PUSC mode in FDM manner with the same tiles/permutation rules. A 16m system can be multiplexed with 16e system in AMC mode in FDM and/or TDM manner. The time length of multiplexed 16e PUSC packets and/or 16m packets can be extended to more than two sub-frames for UL coverage. A PRU for 16m system may consists of 16 sub-carriers by 6 OFDMA symbols, 18 sub-carriers by 6 OFDMA symbols, or 20 sub-carriers by 6 OFDMA symbols when FDM is used.10-22-2009
20090262854Method for transmitting and receiving downlink control information - A method for efficiently transmitting and receiving downlink control information is disclosed. The method includes, at an base station, receiving feedback information including a preceding matrix index (PMI) from an user equipment (UE) and transmitting precoding information having a predetermined bit number according to the number of antenna ports and a transmission mode of the base station. The preceding information of a predetermined transmission mode in the preceding information includes confirmation information indicating that the base station uses a PMI which is recently received from the UE. At this time, if the confirmation information is transmitted via a specific resource block (RB) of an n10-22-2009
20100031117Method for specifying transport block to codeword mapping and downlink signal transmission method using the same - A method for specifying a transport block-to-codeword mapping relationship and a method for transmitting a downlink signal using the same are described. If a swap flag has a first logic value, a first transport block is mapped to a first codeword and a second transport block is mapped to a second codeword. If the swap flag has a second logic value, the first transport block is mapped to the second codeword and the second transport block is mapped to the first codeword. If the size of any one of two transport blocks is 0, the swap flag is not used.02-04-2010
20100046460METHOD OF TRANSMITTING UPLINK CONTROL SIGNALS IN WIRELESS COMMUNICATION SYSTEM - A method of transmitting uplink control signals in a wireless communication system includes preparing a ACK/NACK resource for transmitting the ACK/NACK signal for HARQ of downlink data on an uplink control channel, preparing a scheduling request resource for transmitting a scheduling request and the ACK/NACK signal on the uplink control channel in one subframe, and transmitting the ACK/NACK signal on the uplink control channel configured by the scheduling request resource for the positive transmission of the scheduling request and transmitting the ACK/NACK signal on the uplink control channel configured by the ACK/NACK resource for negative transmission of the scheduling request.02-25-2010
20100054144METHOD AND APPARATUS FOR SELECTING MODULATION AND CODING SCHEME (MCS) INDEX BASED ON FREQUENCY SELECTIVITY - A method of selecting a modulation and coding scheme (MCS) index in a wireless communication system is disclosed. More specifically, the method includes measuring a frequency selectivity of a receiving channel, selecting a MCS index having a coding rate below a prescribed coding rate threshold value if the measured frequency selectivity is greater than or equal to a specified frequency selectivity threshold, and selecting the MCS index having the coding rate above or equal to the prescribed coding rate threshold value if the measured frequency selectivity is less than the specified frequency selectivity threshold.03-04-2010
20100069028ANTENNA SWITCHING METHOD AND METHOD FOR TRANSMITTING AND RECEIVING SIGNALS FOR THE SAME - A closed-loop antenna switching method, a reference signal allocating method, and a feedback signal transmitting method for the same are disclosed. Namely, by transmitting a reference signal via the plurality of transmitting antennas via the antenna switching for reference signal transmission for each prescribed multiple period of an antenna selection period, efficient antenna index information can be fed back. By setting an antenna switching period to a prescribed multiple of an antenna selection period, it is able to prevent power loss and data decoding performance degradation. And, the present invention includes transmitting a sounding reference signal (SRS) for each band selection period via at least one of the plurality of transmitting antennas and transmitting at least one data demodulation reference signal (DMRS) between the band selection periods via an antenna for not transmitting data by reference signal transmission antenna switching.03-18-2010
20100118800METHOD FOR TRANSMITTING DOWNLINK CONTROL CHANNEL IN A MOBILE COMMUNICATIONS SYSTEM AND A METHOD FOR MAPPING THE CONTROL CHANNEL TO PHYSICAL RESOURCE USING BLOCK INTERLEAVER IN A MOBILE COMMUNICATIONS SYSTEM - A method for transmitting a downlink control channel in a mobile communication system and a method for mapping the control channel to physical resources using a block interleaver are provided. In order to transmit a downlink control channel in a mobile communication system, information bits are modulated to generate one or more modulation symbols according to a specific modulation scheme, the modulation symbols are interleaved using a block interleaver, and the interleaved modulated symbols are mapped to resource elements allocated for transmission of at least one control channel in a subframe, thereby transmitting the at least one control channel.05-13-2010
20100118828Method of transmitting scheduling request in a wireless communication system - A method of transmitting a scheduling request which is used to request a radio resource for uplink transmission includes configuring an uplink control channel for transmission of a scheduling request in a subframe, the subframe comprising two consecutive slots, a slot comprising a plurality of single carrier-frequency division multiple access (SC-FDMA) symbols, the scheduling request being carried by presence or absence of transmission of the uplink control channel, and transmitting the scheduling request on the uplink control channel.05-13-2010
20100157933METHOD FOR PERFORMING RANGING PROCEDURE - A method for performing a ranging procedure includes transmitting a ranging request message through a randomly selected ranging slot to a base station, the ranging request message comprising a randomly selected ranging code, and receiving a ranging response message including collision information which informs that collision occurs when at least two user equipments transmit the same ranging code to the base station through the same ranging slot. Delay in the ranging can be reduced.06-24-2010
20100177843METHOD FOR TRANSMITTING SIGNALS FOR ACHIEVING DIVERSITY GAIN - A method for transmitting signals for achieving diversity gain is provided. In a communication system having multiple independent transmission paths, a signal is transmitted by mapping it to different independent transmission paths at initial transmission and at retransmission, thereby obtaining diversity gain. Especially, real and ideal components of a transmission signal are mapped to different transmission paths, thereby obtaining additional gain.07-15-2010
20100199145METHOD AND APPARATUS FOR TURBO ENCODING - An apparatus for encoding an information bit stream using turbo code is provided. The apparatus includes a temporary bit generator for creating a temporary bit stream, an interleaver for independently receiving the information bit stream and the temporary bit stream, a first constituent encoder for independently receiving the information bit stream and the temporary bit stream and generating a first parity bit stream and a second constituent encoder for receiving an output of the interleaver and generating a second parity bit stream. Performance of a turbo code can be enhanced without changing a code rate by making a decoded bit stream longer.08-05-2010
20100220614METHOD OF PERFORMING CHANNEL SOUNDING IN FREQUENCY DUPLEX SYSTEM - A method of performing channel sounding in a frequency division duplex (FDD) system in which an uplink frame and a downlink frame use different frequency bands includes dividing a transmission bandwidth with respect to the uplink frame into a plurality of sounding zones, allocating at least one of the plurality of sounding zones to a user equipment and receiving a sounding signal from the user equipment through the allocated sounding zone. Inter-cell interference can be mitigated and overhead due to transmission of the sounding signal can be reduced.09-02-2010
20100238875METHOD FOR TRANSMITTING VOIP PACKET - A method for transmitting a voice over Internet protocol (VoIP) packet includes allocating a radio resource for VoIP packet transmission to a user, transitioning a VoIP service from a talk period, in which the VoIP packet is transmitted using the radio resource, to a silence period in which the VoIP packet is not transmitted, releasing the radio resource during the silence period, and transitioning the VoIP service to the talk period by reallocating the radio resource. Limited radio resources can be further effectively used.09-23-2010
20100246604METHOD FOR MULTIPLEXING DATA INFORMATION AND CONTROL INFORMATION IN WIRELESS COMMUNICATION SYSTEM - A method for multiplexing a control information stream, and a data information stream comprised of systematic symbols and non-systematic symbols in a wireless mobile communication system is described. The multiplexing method includes mapping the data information stream to a resource area, so that the systematic bit symbols are not mapped to a specific resource area where the control information stream is to be mapped, and mapping the control information stream to the specific resource area.09-30-2010
20100254268METHOD AND APPARATUS FOR MONITORING CONTROL CHANNEL IN MULTIPLE CARRIER SYSTEM - A method and apparatus of monitoring a control channel in a multiple carrier system is provided. A user equipment monitors a plurality of candidate control channels within a control region of a subframe and receives reference control information on a reference control channel which is successfully decoded. The user equipment monitors the control region on a basis of the reference control information and receives link control information on a linked control channel which is successfully decoded. The link control information includes resource assignment information used to receive or transmit data packets via a plurality of component carriers.10-07-2010
20100254331METHOD FOR MULTIPLEXING DATA AND CONTROL INFORMATION - A method for multiplexing a data information stream and two types of control information streams in a wireless mobile communication system is described. The method includes mapping first control information in units of resource elements onto a matrix for generating input information mapped to a resource block, and mapping second control information onto the matrix so as to map the second control information to resource elements adjacent in a time axis to resource elements allocated for a reference signal in the resource block. The first control information is mapped downwards starting from the first row so as not to overwrite the resource element allocated for the reference signal.10-07-2010
20100254471METHOD OF TRANSMITTING POWER INFORMATION IN WIRELESS COMMUNICATION SYSTEM - A method of transmitting power information in a wireless communication system is provided. The method includes: determining energy per resource element (RE) to which a reference signal or data is mapped for downlink transmission; and transmitting power information of the reference signal and the data, wherein the reference signal comprises a channel state indication-reference signal (CSI-RS) for channel state measurement, power information of the CSI-RS is denoted by a ratio of power for a CSI-RS RE and power for a data RE of an orthogonal frequency division multiplexing (OFDM) symbol on which only data is transmitted or power for a cell-specific RS (CRS) RE used for channel state measurement and data demodulation of different OFDM symbols.10-07-2010
20100265862METHOD OF CONTROLLING POWER IN WIRELESS COMMUNICATION SYSTEM - Provided is a method of controlling power of a downlink channel in a wireless communication system, the method including: transmitting at least one data to a user equipment; receiving feedback information for the data from the user equipment; and controlling downlink transmission power using the feedback information. It is possible to control the power without time delay and additional use of radio resources in a VoIP service which is responsible for satisfying a fixed transmission rate in real time. Moreover, it is possible to control the power without waste of control channels to perform PDCCH link adaptation.10-21-2010
20100272037METHOD OF TRANSMITTING BROADCASTING INFORMATION - A method of transmitting broadcasting information or system information to user equipments in an idle mode or a sleep mode in a radio access system is disclosed. The method of transmitting broadcasting information to a user equipment in an idle mode includes receiving information related to the idle mode, decoding a control channel assigned to a first paging subframe according to the information related to the idle mode, and receiving the broadcasting information via a second paging subframe indicated by the control channel regardless of the information related to the idle mode, if the decoding of the control channel is successful.10-28-2010
20100273514METHOD FOR PERFORMING CoMP OPERATION AND TRANSMITTING FEEDBACK INFORMATION IN A WIRELESS COMMUNICATION SYSTEM - A method for performing a Coordinated Multi-Point (CoMP) operation and transmitting feedback information in a wireless communication system is disclosed. The method includes measuring interference levels or noise and interference variances of reference signals received from one or more neighbor cells, and transmitting to a serving Base Station (BS) information about the measured interference levels or noise and interference variances, and information about a Precoding Matrix Index (PMI) that a mobile station (MS) wants to restrict or recommend for a neighbor cell performing the CoMP operation.10-28-2010
20100296472METHOD FOR TRANSMITTING UE-TRIGGERED CHANNEL STATUS INFORMATION - A method for transmitting a user equipment (UE)-triggered channel status information (CSI) is disclosed. A UE transmits a preamble to an eNode B (eNB) through a random access channel (RACH) or a CSI RACH. The UE receives a response allocating a CSI feedback resource or allocating a resource for negotiation from the eNB. The UE transmits the CSI and a UE ID, or only the CSI to the eNB through a physical uplink shared channel (PUSCH) or a physical uplink control channel (PUCCH).11-25-2010
20100309793METHOD OF ESTIMATING SIGNAL-TO-NOISE RATIO, METHOD OF ADJUSTING FEEDBACK INFORMATION TRANSMISSION, ADAPTIVE MODULATION AND CODING METHOD USING THE SAME, AND TRANSCEIVER THEREOF - A method of estimating a signal-to-noise ratio by considering user mobility, a method of adjusting feedback information transmission, an adaptive modulation and coding method using the same, and a transceiver thereof are disclosed. The present invention includes measuring a first channel parameter and a second channel parameter using first and second symbols sequentially received, respectively, estimating a channel quality considering a time delay between measurements of the first and second channel parameters using the first and second channel parameters, and transmitting information for the estimated channel quality if a variation of the first and second channel parameters is equal to or greater than a prescribed threshold. Accordingly, the present invention reduces performance degradation and feedback overhead caused by a time delay in channel quality estimation.12-09-2010
20100316014METHOD OF DESIGNING A MULTIPLEXING STRUCTURE FOR RESOURCE ALLOCATION TO SUPPORT LEGACY SYSTEM - New multiplexing UL structures for supporting legacy system are provided. A 16m system of diversity mode can be multiplexed with 16e system in PUSC mode in FDM manner with the same tiles/permutation rules. A 16m system can be multiplexed with 16e system in AMC mode in FDM and/or TDM manner. The time length of multiplexed 16e PUSC packets and/or 16m packets can be extended to more than two sub-frames for UL coverage. A PRU for 16m system may consists of 16 sub-carriers by 6 OFDM symbols, 18 sub-carriers by 6 OFDM symbols, or 20 sub-carriers by 6 OFDM symbols.12-16-2010
20100322161ADAPTIVE RESOURCE ALLOCATION METHOD IN A WIRELESS COMMUNICATION SYSTEM AND TRANSCEIVER FOR IMPLEMENTING THE SAME - Methods of allocating data to a plurality of subcarriers in a wireless communication system are disclosed. More specifically, one of the methods includes receiving feedback information from a receiver, calculating a level of mobility of the receiver using the feedback information, determining a resource allocation scheme to use based on the calculated level of mobility, and allocating the data to the plurality of subcarriers based on the determined resource allocation scheme.12-23-2010
20100325507METHOD FOR TRANSMITTING A DATA BLOCK IN RADIO COMMUNICATION SYSTEM - A method of transmitting a data block in a wireless communication system is provided. The method includes transmitting the data block, receiving hybrid automatic repeat request (HARQ) not-acknowledgement (NACK) for the data block, receiving an automatic repeat request (ARQ) feedback message indicating a reception state of the data block, and determining whether to retransmit the data block by using the ARQ feedback message.12-23-2010
20110002322DATA TRANSMISSION METHOD IN A MULTI-CARRIER SYSTEM, AND TRANSMITTER - A transmitter includes a plurality of transmit antennas, a processor configured to process user data, and a single carrier frequency division multiple access (SC-FDMA) signal generator configured to receive the user data and generate SC-FDMA symbols transmitted through the plurality of transmit antennas. The SC-FDMA signal generator independently performs inverse fast Fourier transform (IFFT) for each transmit antenna, and each of the plurality of transmit antennas is associated with each of a plurality of carriers.01-06-2011
20110014909METHOD OF TRANSMITTING INTERFERENCE INFORMATION SIGNAL IN WIRELESS COMMUNICATION SYSTEM - A method of transmitting an interference information signal in a wireless communication system is provided. The method includes receiving a neighbor sounding signal from a mobile station (MS) in a neighbor cell, obtaining an interference information signal based on the neighbor sounding signal and transmitting the interference information signal to a neighbor base station (BS), the neighbor BS which is a BS in the neighbor cell.01-20-2011
20110021228MONITORING CONTROL CHANNEL IN WIRELESS COMMUNICATION SYSTEM - A method and apparatus of monitoring a physical downlink control channel (PDCCH) is disclosed. A starting location of a search space in a control region of a subframe k is acquired. The search space is defined by a set of PDCCHs at each aggregation level. The set of PDCCHs from the starting location in the search space at the each aggregation level is monitored. The starting location is defined by the multiple of the aggregation level in the control region.01-27-2011
20110038275METHOD FOR MONITORING CONTROL CHANNEL IN WIRELESS COMMUNICATION SYSTEM - A method for monitoring a control channel in a wireless communication system is provided. The method includes: dividing a control region of a subframe into a common search space having a variable size and monitored by every user equipment (UE) within a cell and a dedicated search space having a variable size and including at least one UE-specific search space to be monitored by at least one UE within the cell, and monitoring a control channel within the common search space; and monitoring a control channel within the UE-specific search space included in the dedicated search space. The performance of an overall system can be improved by effectively monitoring a downlink control channel.02-17-2011
20110051668METHOD FOR TRANSMITTING AND RECEIVING PAGING INFORMATION IN A BROADBAND WIRELESS ACCESS SYSTEM - A method for efficiently transmitting and receiving a paging message and system information from and in a mobile station of a broadband wireless access system is disclosed. A method for receiving a paging message in a mobile station comprise receiving paging information from a serving base station, the paging information including paging sub group identifier (paging sub_group ID) indicating a paging sub group to which the mobile station belongs; and receiving the paging message for a predetermined paging interval of the paging sub group, wherein the paging sub group is determined separately from a paging group and a geographical location determining the paging group, and is maintained while the mobile station is being operated in an idle mode.03-03-2011
20110051680METHOD OF TRANSMITTING UPLINK CONTROL SIGNALS IN WIRELESS COMMUNICATION SYSTEM - A method and device for transmitting uplink control signals in a wireless communication system, the method including: reserving a preassigned scheduling request (SR) physical uplink control channel (PUCCH) resource used for transmission of a SR; determining a frequency domain sequence and an orthogonal sequence based on the preassigned SR PUCCH resource; spreading an ACK/NACK for Hybrid Automatic Repeat Request (HARQ) with the frequency domain sequence and the orthogonal sequence to generate a mapped sequence; and transmitting the mapped sequence03-03-2011
20110051824METHOD AND APPARATUS FOR PERFORMING HARQ IN A MULTIPLE ANTENNA SYSTEM - A method of performing hybrid automatic repeat request (HARQ) in a multiple-antenna system includes receiving a plurality of codewords through an uplink channel, generating acknowledgment (ACK)/not-acknowledgment (NACK) signals respectively for the plurality of codewords, and transmitting the plurality of ACK/NACK signals through a downlink channel in association with a resource used in transmission of the uplink channel. ACK/NACK signals for each codeword in multiple antenna system can be transmitted.03-03-2011
20110064159METHOD AND APPARATUS FOR TRANSMITTING DOWNLINK SIGNAL IN A MIMO WIRELESS COMMUNICATION SYSTEM - A method and apparatus for transmitting a downlink signal in a multiple input multiple output (MIMO) wireless communication system is disclosed. A method for receiving a downlink signal from a base station to a user equipment in a multiple input multiple output (MIMO) system, which supports dual layer transmission based on first and second antenna ports, comprises receiving downlink control information (DCI) through a downlink control channel; and receiving downlink data through a downlink data channel, the downlink data including one or more of a first transport block and a second transport block, wherein the downlink control information includes a new data indicator (NDI) for each of the first and second transport blocks, and if the first transport block is disabled and the second transport block is enabled, the new data indicator for the first transport block indicates an antenna port through which the second transport block is received.03-17-2011
20110075621METHOD OF ACQUIRING SYSTEM INFORMATION IN WIRELESS COMMUNICATION SYSTEM - A method of acquiring system information in a wireless communication system includes receiving scheduling system information including scheduling information indicating a start time of dynamic system information, monitoring the dynamic system information from a start time of the dynamic system information according to the scheduling system information, and ending the monitoring of the dynamic system information upon receiving a system information end indicator indicating an end time of the dynamic system information. Since an end time of dynamic system information is indicated, a process of acquiring system information can be further effectively performed.03-31-2011
20110083066METHOD FOR DETECTING CONTROL INFORMATION IN WIRELESS COMMUNICATION SYSTEM - A method for detecting control information in a wireless communication system is provided. The method includes checking a cyclic redundancy check (CRC) error by monitoring control channels, determining whether a value of an error check field is equal to a specific value, and, if the value of the error check field is equal to the specific value, detecting the control information on the control channel.04-07-2011
20110096715METHOD FOR TRANSMITTING A SIGNAL USING A RELAY STATION IN A WIRELESS COMMUNICATION SYSTEM - A method of transmitting a signal using a relay station is disclosed. In a wireless communication system, the present invention includes the steps of enabling the relay station to receive the signal via a relay interval in a downlink interval using a first wireless communication scheme and a second wireless communication scheme in common from a base station and enabling the relay station to transmit the received signal to a first terminal using the first wireless communications scheme via a first downlink interval in the downlink interval or to a second terminal using the second wireless communication scheme via a second downlink interval.04-28-2011
20110122825METHOD AND APPARATUS OF RECEIVING DATA IN WIRELESS COMMUNICATION SYSTEM - A method and an apparatus of receiving data in a wireless communication system are provided. The method includes detecting a physical downlink control channel (PDCCH) on which control information is transmitted in a first subframe, and receiving data in at least one second subframe based on the control information.05-26-2011
20110134867METHOD AND APPARATUS FOR TRANSMITTING REFERENCE SIGNAL IN MULTIPLE ANTENNA SYSTEM - A method and an apparatus for transmitting a reference signal in a multiple antenna system are provided. The method includes transmitting a first reference signal based on a first sequence through a first antenna group, and transmitting a second reference signal based on a second sequence through a second antenna group, wherein the first reference signal and the second reference signal are transmitted through a same radio resource.06-09-2011
20110134968METHOD AND APPARATUS FOR INFORMATION TRANSMISSION IN A RADIO COMMUNICATION SYSTEM - The present invention relates to a method and an apparatus for information transmission in a radio communication system. The method includes the steps of creating a first symbol and a second symbol relevant to information, creating a first transmission vector and a second transmission vector on the basis of Alamouti code from the first symbol and the second symbol, and transmitting the first transmission vector via a first antenna and transmitting the second transmission vector via a second antenna.06-09-2011

Patent applications by Jae Hoon Chung, Anyang-Si KR