摘要:
Disclosed is a method for indicating an end of transmitting data frames in order to enable a UTRAN (UMTS (Universal Mobile Telecommunications System) Terrestrial Radio Access Network) to assign a common packet channel to another user equipment (UE) in a UE for a CDMA mobile communication system. The UE requests assignment of any one of a number of common packet channels assignable in the UTRAN; the UE is assigned a common packet channel by the UTRAN in response to the to request; the UE sequentially transmits the data frames and their associated control frames over the assigned common packet channel; and the UE transmits at least one control frame, in an appointed field of which a given bit pattern appointed with the UTRAN is registered, in order to inform the UTRAN of an end of data transmission upon completing data transmission through the data frames.
摘要:
An OFDM (Orthogonal Frequency Division Multiplexing) communication system that multiplexes data with a plurality of orthogonal sub-carrier frequencies, which includes a transmitter for converting a serial data stream into parallel data, and segmenting the parallel data into a plurality of blocks having a plurality of data blocks; inserting reference data having information representing a phase value and a position into which the reference symbol is inserted, into each of the segmented blocks; IFFT (Inverse Fast Fourier Transform)-transforming the respective blocks into time-based signals where sub-carrier frequencies are separately assigned to the data blocks; and determining phase factors of the IFFT-transformed time-based signals to reduce a peak-to-average power ratio (PAPR) where non-linear distortion occurs due to coincidence of phases of the data blocks IFFT-transformed with the sub-carrier frequencies, and phase-rotating the IFFT-transformed signals according to the determined phase factors before transmission.
摘要:
A signal transmission apparatus for minimizing a PAPR in an OFDM communication system. A subband divider divides L information data subcarrier signals into M subband signals. An additional information inserter inserts into the L information data subcarrier signals P additional information subcarrier signals having a sign bit indicating insertion of a dummy sequence and an address bit indicating a position of a dummy sequence-inserted subband. A dummy sequence inserter inserts the dummy sequence into a subband in the position. An IFFT block initially generates a first OFDM symbol signal by IFFT-transforming the P additional information subcarrier signals and M dummy sequence-free subband signals, and thereafter generates a second OFDM symbol signal by IFFT-transforming the P additional information subcarrier signals and M dummy sequence-inserted subband signals. A controller determines a sign bit value and an address bit value of the additional information when a PAPR value of the first OFDM symbol signal exceeds a predetermined PAPR threshold, and then performs a control operation of inserting the dummy sequence into a subband in a position corresponding to the address bit value so that the second OFDM symbol signal is transmitted over a downlink.
摘要:
Disclosed is an apparatus and method for reducing a peak-to-average power ratio (PAPR) due to multiple subcarriers in an OFDM (Orthogonal Frequency Division Multiplexing) mobile communication system. In the OFDM mobile communication system, a transmitter pre-emphasizes an output signal of an IFFT (Inverse Fast Fourier Transform) block, and a receiver de-emphasizes a received signal before FFT (Fast Fourier Transform), thereby efficiently reducing PAPR due to multiple subcarriers.
摘要:
A block coding apparatus and method in an OFDM mobile communication system are provided. They reduce PAPR to 3 dB or less, while increasing a traditional block coding rate by twice, by use of complementary sequences. Therefore, spectral efficiency is improved by twice, maintaining the traditional error correction capability, and thus decoding is facilitated.
摘要:
An apparatus and method for transmitting and receiving data having a smallest PAPR in an SLM scheme for PAPR reduction in an OFDM communication system using multiple carriers. To transmit the data having the smallest PAPR, input symbol sequences are duplicated to a plurality of data blocks. Phase-rotated data blocks are generated by multiplying the plurality of data blocks by different phase sequences. Side information for identifying the phase-rotated data blocks is inserted into a predetermined t position of the phase-rotated data blocks. IFFT is performed on the data blocks containing the side information. The data block having the smallest PAPR is selected among the inverse fast Fourier transformed data blocks.
摘要:
A method is disclosed for determining by a UTRAN a persistence value having a value between 0 and 1 for adjusting a number of access preambles from a plurality of UEs requiring assignment of a common packet channel (CPCH). The method includes the steps of counting a number of the access preambles detected in an access preamble period having a predetermined period; and determining the persistence value based on the number of counted access preambles. The persistence value is determined in a unit of transport format (TF), physical common packet channel (PCPCH), or CPCH set.
摘要:
The present invention relates to a system for gating a dedicated physical control channel in a mobile communication system. A UTRAN (UMTS Terrestrial Radio Access Network) transmits a gating start command or a gating end command to a UE (User Equipment) through a specific transport format combination indicator symbol according to whether there exists data transmitted over a downlink physical shared channel and a dedicated physical data channel, thereby to start or end gating the dedicated physical control channel.