Abstract:
A method and apparatus for transmitting and receiving control information in an SC-FDMA system are provided, in which different cyclic shift values are generated for different SC-FDMA symbols in one of a slot and a subframe, a sequence allocated for CDM of control information is cyclically shifted by the cyclic shift values, and a control channel signal including the control information is combined with the cyclically shifted sequences on an SC-FDMA symbol basis and transmitted in the SC-FDMA symbols.
Abstract:
A method for performing cell selection in a mobile communication system and a system therefor. Upon receiving a Multimedia Broadcast and Multicast Service (MBMS) service or a unicast service, a User Equipment (UE) performs cell search separately for each frequency band in an overlapping region between an MBMS-dedicated frequency band and a unicast service-available frequency band. In a first example, the UE allocates different cell identification codes for each cell according to types of the corresponding frequency bands to perform cell search. In a second example, the UE uses the system information broadcasted from the network over P-BCH to indicate whether each cell belongs to the MBMS-dedicated frequency band.
Abstract:
A method for performing burst mapping on transmission data by a transmitter in a mobile communication system using a 16-ary Quadrature Amplitude Modulation (16-QAM) modulation scheme is disclosed. The burst mapping method includes generating control information bits and user data bits by encoding input control information and user data; dividing the control information bits and user data bits into more than two bursts; and arranging a Training Sequence Code (TSC) in a center of each burst, placing the coded control information bits in positions adjacent to the TSC, and swapping the user data bits with bits mapped to higher-reliability positions among the control information bits.
Abstract:
A method and apparatus for transmitting/receiving an ACK/NACK signal to support packet data retransmission in an FDMA wireless communication system are provided, in which an UE generates an ACK/NACK signal for received packet data, determines whether the UE is set to support ACK/NACK repetition, transmits the ACK/NACK signal on a basic response channel mapped to one of a DCH on which the packet data was received and an SCCH carrying scheduling information about the packet data, if the UE is not set to support ACK/NACK repetition, and selects one of supplementary response channels for each ACK/NACK repetition, the supplementary response channels being allocated for ACK/NACK repetition and repeatedly transmits the ACK/NACK signal on the selected supplementary response channel according to a predetermined repetition factor, if the UE is set to support ACK/NACK repetition.
Abstract:
An efficient uplink timing synchronization procedure performed with a target cell upon handover of a User Equipment (UE) in active mode in a mobile communication system is provided, in which a cell transmitter signals to the UE that the uplink timing synchronization procedure is not required in the target cell, and the UE carries out uplink transmission to the target cell at an uplink timing used in a source cell without the uplink timing synchronization procedure.
Abstract:
Disclosed is a method and apparatus for mapping and transmitting coded symbols in a frequency division multiple access system. A pilot is used for channel estimation in the frequency division multiple access system, and the pilot is multiplexed with data before transmission. Multiplexing of the pilot and the data includes a time division multiplexing and frequency division multiplexing. When such multiplexing is used, channel estimation performance varies with positions in which the data is transmitted within in a time-frequency resource. Channel coding for data transmission includes turbo coding, LDPC coding, etc. An output according to such channel coding is divided into a systematic bit and a parity bit. The systematic bit is more important information than the parity bit. Thus, based thereon, the systematic bit is carried in a position where channel estimation is high, and the parity bit is carried in a position where channel estimation performance is low, so that the overall transmission performance can be improved.
Abstract:
Provided is a method and an apparatus for transmitting uplink information items having various characteristics by using a single FFT block. The method includes determining if there is uplink signaling information to be transmitted when there is uplink data to be transmitted; time multiplexing the uplink data and a first pilot for the uplink data and transmitting the multiplexed uplink data and first pilot, when there is no uplink signaling information; and time multiplexing the uplink data, the first pilot for the uplink data, and a second pilot for the uplink data and the uplink signaling information, and transmitting the multiplexed uplink data, first pilot, and second pilot, when there is the uplink signaling information.
Abstract:
A method of transition between distributed transmission mode and localized transmission mode includes steps: the BS transmits measure control message to the UE, the UE makes corresponding measurement and transmits the required measurement report message to the BS, the BS transmits transition indicator message of new mode to the UE based on measurement report message sent from the UE; CQI report and downlink transmission of new mode between the UE and the BS begins. The BS of the present invention can choose more appropriate transmission mode for downlink transmission based on changing characteristics of the channel in time domain and frequency domain.
Abstract:
A method and an apparatus for measurement report for the decision of transmission mode transition are disclosed. The method comprising steps of: obtaining a threshold value of reporting CQI difference of all frequency sub-bands; measuring a CQI value at each CQI reporting frequency sub-band of whole frequency band in each measure time interval; determining a CQI difference value based on the measured CQI value of each CQI reporting frequency sub-band; and comparing the determined CQI difference value with the threshold value, if a condition is satisfied, then the UE sending the determined CQI difference value to the BS. In present invention, after the UE has reported this measurement report to the BS, the BS may choose more suitable data transmission mode for the UE based on this measurement report to make data be transmitted more effectively.
Abstract:
A transmission/reception apparatus and method are provided for channel estimation in a mobile communication system for transmitting packet data based on FDMA, and include a transmitter for transmitting signals through a pilot channel and a control channel, and a receiver for receiving the signals of the pilot channel and the control channel and estimating a channel for demodulation of a data channel using the signal of the pilot channel and information about transmission power used when the control channel is transmitted. The receiver includes a pilot channel receiver, a control channel receiver, a control channel signal reproducer, and a channel estimator for performing channel estimation using the signals received through the pilot channel, the control channel, the signal transmitted through the control channel by the transmitter, and the information about transmission power used when the control channel is transmitted by the transmitter.