Abstract:
A method for generating a downlink frame and a method for searching a cell are provided to improve cell searching performance by reducing interference between sectors by scrambling a short sequence to a scrambling sequence. A first shot sequence and a second short sequence expressing cell group information are generated. A first scrambling sequence and a second scrambling sequence determined by the first synchronous signal are generated. A third scrambling sequence determined by the first shot sequence and a fourth scrambling sequence determined by the second short sequence are generated. The first shot sequence is scrambled to the first scrambling sequence. The second short sequence is scrambled to the second scrambling sequence and the third scrambling sequence. The second short sequence is scrambled to the first scrambling sequence. The first shot sequence is scrambled to the second scrambling sequence and fourth scrambling sequence(S510). A down link frame including the first short sequence scrambled to the first scrambling sequence, the second short sequence scrambled to the second scrambling sequence and the third scrambling sequence, the second short sequence scrambled to the first scrambling sequence, and the first short sequence scrambled to the second scrambling sequence and the fourth scrambling sequence is generated(S530). The frame of the inputted downlink signal is transmitted through the transmission antenna(S540).
Abstract:
A method for generating a downlink frame and a method for searching a cell are provided to reduce interference between sectors by scrambling a short sequence to a scrambling sequence. A sequence generator generates a plurality of short sequences and a plurality of scrambling sequences for reducing the adjacent cell interference and transmits the generated sequence to a synchronization signal generator(S510). The synchronization signal generator generates a secondary synchronization signal by using the short sequence and the scrambling sequence received from the sequence generator(S520). A frequency mapping unit generates a downlink frame by mapping data to be transmitted to time and frequency domains by using transmission traffic data and the secondary synchronization signal generated in the synchronization signal generator(S530). An OFDM transmitter transmits the frame of the downlink signal through a transmission antenna(S540).
Abstract:
A method for generating a downlink frame and a cell search method are provided to equalize the inter-sector interference. A sequence generation part produces the first shot sequence for showing cell group information and the second short sequence(S510), generates the first scrambling sequence determined by the first synchronous signal, and then produces the second scrambling sequence decided by the group to which the first shot sequence belongs. A wireless communication system uses a plurality of short sequences and a plurality of short sequences are divided into a plurality of groups. A frequency mapping part makes the first shot sequence to the first scrambling sequence, and then makes the second short sequence into the second scrambling sequence(S530,S540).
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 data re-transmission method by interference averaging and an apparatus using the same are provided to reduce interference by making orthogonal code groups for different mobile stations when repetitively transmitting data. A data re-transmission method by interference averaging between terminals in a mobile communication system comprises the following steps of: re-partitions a plurality of terminals into a plurality of subgroups so that terminals belonging to each subgroup can be different according to data re-transmission(S510); re-assigning orthogonal codes and resources to the terminals belonging to each subgroup(S530, S550); and assigning different frequency bands to the terminal whenever data is re-transmitted(S570).
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 signal transmission method is provided to apply transmission diversity methods of BCH(Broadcast Channel) information variously according to a distance between SCH(Synchronization Channel) information and the BCH information, thereby magnifying a time diversity gain within a TTI(Transmission Time Interval). Plural SCH and BCH symbols are assigned to plural symbol intervals, respectively. The first transmission diversity method is applied to the SCH symbols and BCH symbols adjacent to the SCH symbols. The second transmission diversity method is applied to the BCH symbols isolated from the SCH symbols. The SCH symbols and the BCH symbols are transmitted.
Abstract:
A method and an apparatus for transmitting an uplink signal in a communication system are provided to reduce overhead caused by a reference signal by allocating a reference signal having a large bandwidth. A sounding reference signal is disposed in a frame(S510). The sounding reference signal is converted into a transmission signal of a time domain through reverse FFT(Fast Fourier Transform)(S520). A guard interval is inserted into the transmission signal of the time domain(S530). The analog transmission signal is converted into a wireless frequency to be transmitted through a transmitting antenna(S540).
Abstract:
A method for transmitting a signal and information of an antenna, and a method for estimating the number of antennas are provided to enable a mobile station to demodulate a BCH(Broadcast Channel) as channel response obtained through a SCH(Synchronization Channel) by applying the multiple free coding vectors to the BCH and SCH timely close to each other. A base station creates a plurality of SCH symbols out of a cell group identifier and a cell identifier, at this time a part of information about the number of transmission antennas is added to the synchronization channel symbols(S210). The base station creates BCH symbols out of the rest information about the number of transmission antennas(S220). The base station creates a downstream frame by disposing the SCH symbols and the BCH symbols in a symbol section respectively(S230). And the base station transmits the downstream frame(S240).