Abstract:
A cell search method for an OFDM(Orthogonal Frequency Division Multiplexing) based FDD(Frequency Division Duplex) and TDD(Time Division Duplex) dual mode mobile station and base station transmission scheme is provided to realize a cell searcher for simply operating both an FDD mode and a TDD mode. A method for transmitting a forward synchronization signal includes the steps of: generating a frame including a plurality of sync blocks; and transmitting the frame through a forward link, wherein the frame includes a first SCH(Synchronization Channel) sequence and a plurality of second SCH sequence and specifies a cell identifier by the first SCH sequence and the plurality of second SCH sequence. The first SCH sequence supplies sync block timing information and the plurality of second SCH sequences supply frame timing information. Both the first SCH sequence and the second SCH sequences are used in TDD and FDD systems.
Abstract:
Downlink resource allocation for an OFDMA system is provided to transmit allocation information about resources to be used in an MS(Mobile Station) when a BS(Base Station) transmits downlink scheduling information to the MS, thereby maximizing the amount of resources used in data transmission and increasing a data transmission rate. A method for transmitting resource allocation information comprises the following steps of: constructing continuous physical resources as a sub band; constructing the sub band allocation information as a binary bitmap to transmit the constructed binary bitmap to a first control channel; and constructing allocation information within the sub band regarding the sub band as a binary bitmap to transmit the constructed binary bitmap to a second control channel.
Abstract:
An uplink signal transmission method of a communication system, a transmission device, a generation method, and a generation device are provided to randomize interference between users and cells when a frequency domain CDM(Code Division Multiplexing) method is used, thereby reducing the interference between users. At the first transmission time, the first sequence for distinguishing a terminal from another terminal is multiplied by the first transmission symbol to transmit the multiplied sequence. At the second transmission time different from the first transmission time, the second sequence for distinguishing the terminal from another terminal is multiplied by the second transmission symbol to transmit the multiplied sequence. The second sequence is different from the first sequence.
Abstract:
A data transmission method of an MS(Mobile Station) using a cell search signal and a device thereof are provided to enable the MS to determine a location by itself by using cell search signals received from base stations within a home cell and neighboring cells, and to estimate uplink delay time information, thereby omitting RACH(Random Access Channel) burst transmission. An MS receives cell search signals from base stations within a synchronized home cell and base stations within at least more than neighboring cell(S710). The MS calculates receiving time differences between the cell search signals received from the base stations within the home cell and the neighboring cells(S720). The MS calculates uplink delay time of the neighboring cells based on the receiving time differences(S730).
Abstract:
A cell search method in an OFDM(Orthogonal Frequency Division Multiplexing) cellular system, a frame transmission method therefor, and a forward link frame structure are provided to smoothly perform handover by effectively searching an adjacent cell, and reduce the amount of battery consumption of a mobile station. The first detecting unit obtains symbol synchronization by applying a matching filter to a reception signal(S800). A hop pattern correlation values are calculated by using reception synchronous channel symbols extracted from the reception signal based on the obtained symbol synchronization information, and a hop pattern of a target cell is detected based on the calculated hop pattern correlation values(S820). A code group and a frame boundary of the target cell are detected based on the detected hop pattern(S840). Pilot correlation values of common pilot channel symbols and scrambling codes belonging to the detected code group are calculated, and the scrambling codes of the target cell are detected based on the calculated pilot correlation value(S860). It is checked whether the detection results are reliable(S880).
Abstract:
A method for transmitting uplink control information in a mobile communication system is provided to configure the uplink control information transmitted from a base station of the mobile communication system for packet transmission to a terminal through a downlink and transmit the information as occupying minimum radio resources, thereby maximizing utilization of the limited radio resources. A method for transmitting uplink control information in a mobile communication system comprises the following steps of: generating uplink control information(S110); allocating the uplink control information on a downlink-shared radio resource for packet data transmission by using downlink scheduling information(S120); and transmitting the radio resource to a terminal(S130).
Abstract:
A transmission method for obtaining random access diversity in a mobile station is provided to increase the RACH(Random Access CHannel) signature detection probability of a base station by applying a TSTD(Time Switching Transmit Diversity) technique, a frequency hopping technique, and a power ramping technique to RACH burst transmission in various combinations. A transmitting apparatus having two Tx antennas(140,150) in a mobile station comprises an OFDMA(Orthogonal Frequency Division Multiple Access) modulating unit(110), a transmitting unit(120), and a power controlling unit(130). The OFDMA modulating unit(110) allocates an RACH burst(S1) to a specific subband, executes OFDMA modulation, and makes an RACH burst signal(S2). If an ACK signal for the RACH burst is received from a base station, the OFDMA modulating unit(110) modulates user packet data containing an RACH message and transmits the modulated data to the transmitting unit(120). The transmitting unit(120) transmits the RACH burst signal(S2), outputted from the OFDMA modulating unit(110), to the base station using the Tx antennas(140,150) alternately. If the ACK signal for the RACH burst is received, the transmitting unit(120) amplifies and upconverts the OFDMA-modulated user packet data and transmits the data through a Tx antenna which receives the ACK signal. The power controlling unit(130) creates a control signal(S4) to control the power of the RACH burst signal(S2).
Abstract:
A method for transmitting signals in a base station and a method for transmitting feedback information in a mobile terminal are provided to decrease the amount of feedback information, transmitted to a base station from a mobile terminal, by previously allocating some precoding matrixes or Tx antennas to each frequency group. A base station segments an allocated frequency band into a plurality of frequency groups. The base station allocates one or more precoding matrixes among a plurality of precoding matrixes to each of the divided frequency groups. The base station receives feedback information from a mobile terminal. The base station transmits signals using the frequency of a frequency group corresponding to the received feedback information and the precoding matrixes allocated to the corresponding frequency group.
Abstract:
본 발명은 유무선통신 채널코딩 분야의 기술로 단일 코덱을 이용하여 복수의 부호율을 갖는 부호를 부호화하고 복호화하는 기술에 관한 것으로, 패러티 검사 행렬과 같은 구조를 갖는 상기 다중 부호율 부호를 얻기 위해 모부호의 변수 노드에 새로운 패러티를 순차적으로 붙여나가는 단계를 포함하는 다중 부호율 LDPC 부호의 디자인 방법을 개시한다. 본 발명이 제시하는 최적 붙임 방법을 사용하면 최적의 성능을 유지하면서 높은 부호율의 부호를 기본 부호로 하여 복수개의 낮은 부호율 부호를 포함하는 단일 코덱을 디자인 할 수 있다. 채널 코드(Channel Code), LDPC 부호, 다중 부호율(Rate-compatibility), 최적 붙임 방법(Optimal extending)
Abstract:
본 발명은 제 1 LDPC 부호 및 제 2 LDPC 부호 및 이들을 연결하는 인터리버로 구성된 병렬연접 LDPC 부호의 패러티 검사행렬의 형성 방법에 있어서, (a) 상기 제 1 LDPC 부호의 디그리 분포 및 상기 제 2 LDPC 부호의 디그리 분포를 구하는 단계, 및 (b) 상기 디그리 분포를 만족하는 상기 제 1 LDPC 부호의 패러티 검사행렬 및 상기 제 2 LDPC 부호의 패러티 검사행렬을 형성하는 단계를 포함하며, 상기 (a) 단계에 있어서, 상기 제 1 및 2 LDPC 부호의 디그리 분포는 밀도전개 방법에 의한 성능 측정을 이용하여 구하여지며, 상기 밀도전개 방법에 있어서, 상기 제 1 LDPC 부호의 변수노드에서 체크노드로 전달되는 메시지의 확률밀도는 상기 제 2 LDPC 부호로부터 출력되는 외부 정보의 확률 밀도를 반영하며, 상기 제 2 LDPC 부호의 변수노드에서 체크노드로 전달되는 메시지의 확률밀도는 상기 제 1 LDPC 부호로부터 출력되는 외부 정보의 확률 밀도를 반영하는 것을 특징으로 하는 병렬연접 LDPC 부호의 패러티 검사행렬의 형성 방법을 제공한다. 오류정정 부호(error-correcting codes), 저밀도 패러티 검사 부호(low-density parity-check codes, LDPC codes), 척도 없는 네트워크(scale-free networks), 이레이져 채널(erasure channel).