Abstract:
A method for mapping a secondary synchronization channel symbol in an OFDM cellular system and a base station using the same remove unclearness between other cells in a mapping proves by setting at least one of two orthogonal code sequences to an index value to add or multiply an arbitrary number to or by the orthogonal code sequence index allocated to a first secondary synchronization channel symbol and performing mapping. A first orthogonal code sequence(301) and a second orthogonal code sequence(302) allocated to the first secondary synchronization channel symbol are cross-mapped and allocated to a second secondary synchronization channel symbol. At least one of two orthogonal code sequences is set to an index value adding or multiply the arbitrary number to or by the orthogonal code sequence index allocated to the first secondary synchronization channel symbol and then is mapped. The arbitrary number is the natural number.
Abstract:
A signal transmission method and an apparatus therefor are provided to reduce the decoding delay time in a terminal, and enable a base station to efficiently manage resources. In a base station, a method for transmitting signals includes the following steps. Transmission information consisting of a plurality of frames is renewed at a transmission information update period. In each frame within the transmission information period, channel coding is performed for the transmission information by using a scrambling code. The channel-coded transmission information is converted into the transmission symbol. The transmission symbol is transmitted. In each of frames within the transmission information period, different scrambling codes are used.
Abstract:
A handover method between wireless communication systems each using a different wireless access technology and a method for transmitting a forward synchronization signal therefore are provided to perform seamless handover by providing a frame structure including an SCH(Synchronous Channel)/P-BCH(Primary-Broadcasting Channel) supporting measurement of handover. An MS(Mobile Station)(500), which communicates with a home base station(S0) acquires information such as the number of transmission antennas of a target base station, and bandwidth information(S1). The MS reports the information to the home base station(S2). The home base station inquires a target base station(520) as to whether the MS can perform handover(S3). If there is available radio resources, the target base station informs the home base station accordingly(S4). The home base station instructs the MS to perform handover(S5). The MS transmits a handover preamble to the target base station(S6). The target base station allocates resources for data communication to the MS(S7). The MS communicates with the target base station with the allocated radio resources to thus complete inter RAT handover(S8).
Abstract:
A wet station of semiconductor manufacturing equipment is provided to accelerate a manufacturing speed of a semiconductor device by performing chemical, rinsing, and drying processes in a single bath. A wet station of semiconductor manufacturing equipment includes a bath(110), a chuck(120), plural nozzles(130), a tube(140), a storage tank(150), and a controller(160). The chuck holds a wafer and transfers the wafer in and out of the bath. The nozzles are installed in the bath. The tube is connected to the nozzles. The storage tank is connected to the tube. DI(De-Ionized) water, a chemical, and a nitrogen gas are embedded in the storage tank. The controller controls an operation of the chuck and selectively sprays the DI water, the chemical, and the nitrogen gas into the nozzle.
Abstract:
A wired link tester for checking the performance of a multiple antenna system is provided to configure wired links in response to wireless links for the multiple antenna system, thereby reproducing a status that a signal transmitted from a transmitting antenna is received to all receiving antennas. A wired link tester(120) is connected to a BS1(111), a BS2(112), a terminal(130), and an external computer(140) to configure a test environment. The wired link tester comprises a fast fading reproduction unit(200), a path loss reproduction unit(300), and a control unit(600). The fast fading reproduction unit makes the wired link tester configure 16 wired links in response to 16 wireless links for the maximum 4x4 multiple antenna system, and reproduces a status that a RF(Radio Frequency) signal transmitted from a transmitting antenna is received to all receiving antennas, and changes the characteristics of a variable attenuator and a variable phase shifter according to the control signal of the control unit to reproduce fast fading characteristics. The path loss reproduction unit forms 16 wired links with the fast fading reproduction unit, and changes the characteristics of a variable attenuator positioned at the path loss reproduction unit according to the control signal of the control unit to reproduce path loss characteristics. The control unit prestores a value for reproducing the characteristic of a wireless link and controls the fast fading reproduction unit and the path loss reproduction unit according to the prestored value.
Abstract:
OFDM 셀룰라 시스템에서의 셀 탐색 방법, 이를 위한 프레임 송신 방법, 및 순방향 링크 프레임 구조가 개시된다. 이 셀 탐색 방법은 각 기지국이 소속 셀의 프레임을 송신함에 따라, 상기 복수 개의 기지국으로부터 수신되는 수신신호를 이용하여 단말이 타겟 셀을 탐색하는 방법에 있어서, 상기 각 셀의 프레임은 상기 셀의 도약패턴 -- 상기 도약패턴은 M(2 이상의 자연수) 개의 동기채널코드시퀀스를 포함하며, 상기 셀의 스크램블링코드가 속하는 코드그룹과 일대일대응됨--에 따라 코드 도약된 M개의 동기채널심볼들을 포함하고, 상기 OFDM 셀룰라 시스템에서 사용되는 임의의 도약패턴은 상기 도약패턴의 싸이클릭쉬프트된 결과, 타 도약패턴, 및 상기 타 도약패턴의 싸이클릭쉬프트된 결과와 다르며, 상기 수신신호 중 동기채널심볼위치에 해당되는 신호인 수신동기채널심볼들을 이용하여, 타겟 셀의 도약패턴을 검출하는 도약패턴검출단계; 및 상기 검출된 도약패턴을 기초로, 상기 타겟 셀의 코드그룹을 검출하는 코드그룹검출단계를 포함한다. 본 발명에 따르면, 낮은 복잡도로 셀 탐색 시간을 줄일 수 있다.
Abstract:
본 발명은 두 개의 짧은 직교 시퀀스의 조합으로 이루어져 있는 2차 동기채널 구조에서 시퀀스 매핑을 수월하게 할 수 있는 방법을 제공하고자 하는 것이다. 3G LTE의 경우 2차 동기채널은 이동국에게 셀 그룹 정보, 프레임 경계 정보 등을 제공한다. 이러한 정보들은 상기 짧은 2개의 직교 시퀀스의 번호를 통해 이동국에 제공되는데 본 발명은 이러한 정보들을 상기 2차 동기채널의 짧은 2개의 직교 시퀀스 번호에 효율적으로 매핑 시키는 방법을 제공한다. OFDM, 2차동기채널
Abstract:
통신 시스템에서 복수의 섹터가 동일한 신호를 전송하는 경우에, 동일한 신호에 가중치를 적용하여 전송한다. 이때, 가중치 패턴을 심볼 전송 시간과 섹터 번호에 따라 다르게 설정하여, 단말기에서의 동일한 신호의 수신 불량을 줄일 수 있다. 셀, 섹터, 공통 신호, SCH, 위상 가중치, 위상 회전