Patent application number | Description | Published |
20090067370 | CELL SEARCH METHOD IN OFDM CELLULAR SYSTEM, FRAME TRANSMISSION METHOD THEREOF, AND FORWARD LINK FRAME STRUCTURE - Provided are a cell search method, a frame transmission method thereof, and a forward link frame structure thereof. The cell search method used by a terminal to search a target cell using reception signals received from a plurality of base stations, each base station transmitting a frame of its cell, in an Orthogonal Frequency-Division Multiplexing (OFDM) cellular system comprising a plurality cells to which a cell-specific scrambling code is assigned includes: detecting a hopping pattern of the target cell using reception sync channel symbols, which are signals corresponding to sync channel symbol positions of the reception signals, wherein the frame of each cell comprises M sync channel symbols code-hopped according to a hopping pattern of the cell, where M is a natural number equal to or greater than 2, each hopping pattern containing M sync channel code sequences and respectively corresponding to each code group to which a scrambling code of each cell belongs, and an arbitrary hopping pattern used in the OFDM cellular system differs from a cyclically shifted result of the hopping pattern, other hopping patterns, or cyclically shifted results of the other hopping patterns; and detecting a code group of the target cell based on the detected hopping pattern. Accordingly, a cell search time and the complexity of the cell search can be reduced. | 03-12-2009 |
20090080385 | CELL SEARCH METHOD, FORWARD LINK FRAME TRANSMISSION METHOD, APPARATUS USING THE SAME AND FORWARD LINK FRAME STRUCTURE - Provided are a cell search method, a forward link frame transmission method, an apparatus using the methods, and a forward link frame structure in an Orthogonal Frequency Division Multiplexing cellular system, wherein the time it takes to perform a cell search and the complexity of the cell search can be reduced. The cell search apparatus includes a sync acquirer which receives a signal according to a forward link frame comprising a plurality of sync channel symbols each having different intervals between the adjacent sync channel symbols and achieves synchronization of the sync channel symbols using a sync channel of the received signal, and a boundary detector which detects a frame boundary using an interval pattern between the sync channel symbols, based on the achieved synchronization. | 03-26-2009 |
20090175161 | Transmission Method Of Mobile Station For Random Access Channel Diversity - A transmission method performed by a mobile station for random access channel (RACH) burst transmission diversity gain is provided. According to the method, by combining and using switching diversity by beam forming, frequency hopping, and power ramping, the probability that when the speed of a mobile station is low, the mobile station falls into a deep fading environment is lowered, thereby increasing the probability of detecting an RACH signature of the base station. Also, by using the transmission parameters (subbands, precoding matrixes, power, etc.) which are used for successful transmission of an RACH burst, for transmission of a successive user packet data, reliable transmission of the successive user packet data can be performed. | 07-09-2009 |
20090175220 | TRANSMISSION METHOD OF MOBILE STATION FOR RANDOM ACCESS CHANNEL DIVERSITY - A transmission method performed by a mobile station for random access channel (RACH) burst transmission diversity gain is provided. According to the method, a variety of combinations of a time switching transmit diversity (TSTD) technique, a frequency hopping technique, and a power ramping technique that are robust against fading channel environments are applied to transmission of an RACH burst, thereby increasing the probability of detecting an RACH signature of a base station. Also, by using the transmission parameters (subband frequencies, transmission antennas, power, etc.) which are used for successful transmission of an RACH burst, for transmission of a successive user packet data, reliable transmission of the successive user packet data can be performed. | 07-09-2009 |
20090219882 | CELL SEARCH METHOD, FORWARD LINK FRAME TRANSMISSION METHOD, APPARATUS USING THE SAME AND FORWARD LINK FRAME STRUCTURE - Provided are a cell search method, a forward link frame transmission method, an apparatus using the methods, and a forward link frame structure. The cell search apparatus includes a sync acquirer acquiring synchronization of sync channel symbols using a sync channel of a forward link, and a group detector detecting at least one hopping codeword element belonging to a hopping codeword of a target cell from a forward link signal containing sync channel symbols sequence-hopped using a hopping codeword corresponding to a code group to which a scrambling code of each cell belongs based on the acquired synchronization, and detecting a code group of the target cell based on the detected hopping codeword element, wherein the hopping codewords are orthogonal to a cyclic shift operation. Accordingly, a cell search time and the complexity of the cell search can be reduced. | 09-03-2009 |
20100074191 | RANDOM ACCESS METHOD USING DIFFERENT FREQUENCY HOPPING PATTERNS BETWEEN NEIGHBORING CELLS AND MOBILE COMMUNICATION DEVICE - Provided are a random access method of a mobile station and a mobile communication device performing the same. The mobile station can obtain a diversity gain without a Random Access Channel (RACH) burst collision by hopping according to a cell group in a frequency domain and transmitting a random access when random access resources are used between neighboring cells and detect an RACH even with low transmission power by applying switching diversity together with the frequency hopping. | 03-25-2010 |
20100172330 | METHOD FOR SIGNAL TRANSMISSION IN WIRELESS SYSTEMS - Provided is a method of forming a signal in a wireless communication system in which a plurality of terminals commonly use time and frequency resources for efficient code hopping. The method includes allocating the same frequency-axis sequence and different time-axis sequences to a plurality of terminals by using a resource index according to a first slot in the first slot; and allocating different frequency-axis sequences and different time-axis sequences to the plurality of terminals by using a resource index according to a second slot in the second slot. | 07-08-2010 |
20100182976 | METHOD FOR TRANSMITTING CONTROL INFORMATION IN WIRELESS COMMUNICATION SYSTEMS - When a plurality of terminals share the same resources in a wireless communication system, and when control information such as acknowledgement/negative acknowledgement (ACK/NAK) information or scheduling information is transmitted, a method of efficiently performing code division multiplexing (CDM) is required to distinguish the plurality of terminals. In particular, it is necessary to develop a method by which a code sequence of CDM can be selected and used according to each cell condition. Provided is a method of forming a signal in a wireless communication system in which a plurality of terminals commonly share frequency and time resources. The method includes the operations of receiving condition information in a cell; selecting one of a plurality of time domain orthogonal sequences having different lengths, according to the condition information; and allocating the selected time domain orthogonal sequence to a control signal symbol block. | 07-22-2010 |
20100208709 | METHOD OF TRANSMITTING ACK/NACK BIT SUPPORTING HARQ IN MOBILE COMMUNICATION SYSTEM SUPPORTING MULTI USER MIMO - Provided is a method of efficiently transmitting an acknowledgement/negative acknowledgement (ACK/NACK) bit supporting hybrid automatic repeat request (HARQ) in a wireless communication system supporting multi-user multi-input and multi-output (MIMO). The method transmits the same downlink code and in-phase/quadrature (I/Q) multiplexed ACK/NACK bit to two mobile stations using the same uplink resource block. Accordingly, the method can efficiently transmit the ACK/NACK bit for multi-user MIMO and efficiently use downlink radio resources. | 08-19-2010 |
20110085495 | METHOD AND APPARATUS FOR FORMING SIGNALS IN WIRELESS COMMUNICATION SYSTEMS - Provided is method of forming a signal in a wireless communication system in which a plurality of terminals commonly use a resource in the time domain and the frequency domain. The method includes multiplying a signal to be transmitted by a frequency domain orthogonal code symbol corresponding to a first cyclic shift index in a first slot to be transmitted to a base station, wherein the multiplying is performed by a first terminal and a second terminal; and multiplying information to be transmitted by a frequency domain orthogonal code symbol corresponding to a second cyclic index that is different from the first cyclic index of the first slot to be transmitted to the base station, in a second slot, wherein the multiplying is performed by the first terminal and the second terminal. | 04-14-2011 |
20120307789 | METHOD AND APPARATUS FOR FORMING SIGNALS IN WIRELESS COMMUNICATION SYSTEMS - Provided is method of forming a signal in a wireless communication system in which a plurality of terminals commonly use a resource in the time domain and the frequency domain. The method includes multiplying a signal to be transmitted by a frequency domain orthogonal code symbol corresponding to a first cyclic shift index in a first slot to be transmitted to a base station, wherein the multiplying is performed by a first terminal and a second terminal; and multiplying information to be transmitted by a frequency domain orthogonal code symbol corresponding to a second cyclic index that is different from the first cyclic index of the first slot to be transmitted to the base station, in a second slot, wherein the multiplying is performed by the first terminal and the second terminal. | 12-06-2012 |
20130044729 | METHOD FOR SIGNAL TRANSMISSION IN WIRELESS SYSTEMS - A method is provided for forming a signal in a wireless communication system in which a plurality of terminals commonly use time and frequency resources for efficient code hopping. The method includes allocating the same frequency-axis sequence and different time-axis sequences to a plurality of terminals by using a resource index according to a first slot in the first slot; and allocating different frequency-axis sequences and different time-axis sequences to the plurality of terminals by using a resource index according to a second slot in the second slot. | 02-21-2013 |
20130163557 | METHOD FOR TRANSMITTING CONTROL INFORMATION IN WIRELESS COMMUNICATION SYSTEMS - When a plurality of terminals share the same resources in a wireless communication system, and when control information such as acknowledgement/negative acknowledgement (ACK/NAK) information or scheduling information is transmitted, a method of efficiently performing code division multiplexing (CDM) is required to distinguish the plurality of terminals. In particular, it is necessary to develop a method by which a code sequence of CDM can be selected and used according to each cell condition. Provided is a method of forming a signal in a wireless communication system in which a plurality of terminals commonly share frequency and time resources. The method includes the operations of receiving condition information in a cell; selecting one of a plurality of time domain orthogonal sequences having different lengths, according to the condition information; and allocating the selected time domain orthogonal sequence to a control signal symbol block. | 06-27-2013 |
20130287003 | CELL SEARCH METHOD, FORWARD LINK FRAME TRANSMISSION METHOD, APPARATUS USING THE SAME AND FORWARD LINK FRAME STRUCTURE - A method of and an apparatus therefor searching a cell in a mobile station of a communication system in which a plurality of cells are grouped into a plurality of cell groups, and each cell group includes at least two cells. The method includes detecting a primary synchronization signal and a secondary synchronization signal from a received signal, and identifying a cell based on a combination of the primary synchronization signal and the secondary synchronization signal. The secondary synchronization signal is related to the cell group to which the mobile station belongs and the primary synchronization signal is related to the cell to which the mobile station belongs within the cell group. | 10-31-2013 |