摘要:
Method and apparatus for transmitting/receiving an uplink pilot used for channel estimation and measurement of an uplink in an FDMA system. Pilot symbols are transmitted with different frequency mapping patterns in first and second pilot symbol intervals of one time slot interval including data symbol intervals and the inconsecutive first and second pilot symbol intervals which have a shorter length than the data symbol intervals. As a result, interpolation of a frequency domain during channel estimation is not necessary, and can correctly obtain channel-estimated values of a frequency at which data is transmitted, in a fast time-varying channel environment.
摘要:
Method and apparatus for transmitting/receiving an uplink pilot used for channel estimation and measurement of an uplink in an FDMA system. Pilot symbols are transmitted with different frequency mapping patterns in first and second pilot symbol intervals of one time slot interval including data symbol intervals and the inconsecutive first and second pilot symbol intervals which have a shorter length than the data symbol intervals. As a result, interpolation of a frequency domain during channel estimation is not necessary, and can correctly obtain channel-estimated values of a frequency at which data is transmitted, in a fast time-varying channel environment.
摘要:
An apparatus and method for allocating resources in an Single Carrier-Frequency Division Multiple Access (SC-FDMA) communication system are provided, in which a Node B determines on a cell basis whether to turn or off inter-subband hopping and whether to turn on or off mirroring for a resource unit for the UE on a frequency axis along which at least two subbands are defined, at set hopping times, selects a resource unit by selectively performing inter-subband hopping and mirroring on the resource unit for the UE according to the determination, and allocates the selected resource unit to the UE.
摘要:
A method, apparatus and system for efficiently transmitting and receiving channels are provided in a wireless communication system based on Orthogonal Frequency Division Multiplexing (OFDM). A multiplexing scheme differs according to a channel when a transmitter transmits a packet data channel, a common control channel and a control channel designated for a particular user. Uncoded 1-bit information is broadly dispersed in frequency and time domains using multiplexing technology for maximizing diversity gain in a channel for transmitting information of at least one bit to a particular user like an acknowledgement (ACK) channel. The transmitter converts a sequence obtained by multiplexing multiple bits to be transmitted to a plurality of users to parallel signals, and broadly disperses the parallel signals in the time and frequency domains. When the uncoded 1-bit information is transmitted, reception reliability is improved because channel coding and transmission are efficiently performed using a small amount of resources.
摘要:
An apparatus for transmitting data in a frequency division multiple access based communication system is disclosed. The apparatus includes a symbol block generator for generating a symbol block in a predetermined symbol block period within one TTI when control information to be transmitted exists in the TTI, an FFT unit for performing FFT on the symbol block, and an IFFT unit for performing IFFT on signals output from the FFT unit and then transmitting the signals. The symbol block includes the control information and data to be transmitted. The TTI includes multiple symbol block periods.
摘要:
An apparatus for transmitting data in a frequency division multiple access based communication system is disclosed. The apparatus includes a symbol block generator for generating a symbol block in a predetermined symbol block period within one TTI when control information to be transmitted exists in the TTI, an FFT unit for performing FFT on the symbol block, and an IFFT unit for performing IFFT on signals output from the FFT unit and then transmitting the signals. The symbol block includes the control information and data to be transmitted. The TTI includes multiple symbol block periods.
摘要:
A method and apparatus for efficiently transmitting channel quality information in an OFDM communication system using dynamic channel allocation and adaptive modulation, and determining parameters required for time-division channel quality information transmission in an asynchronous CDMA communication system are provided. In the OFDM communication system in which a plurality of subcarriers are allocated to a plurality of UEs, the subcarriers are divided into a plurality of subcarrier groups each having at least one subcarrier. Each of the UEs determines and transmits the channel quality information of each of the subcarrier groups according to predetermined transmission parameters at transmission time points that do not overlap with those of other UEs. A Node B dynamically allocates the subcarriers to the UEs and their corresponding modulation schemes according to the channel quality information.
摘要:
Provided is an apparatus for signal transmission in a Fast Frequency Hopping-Orthogonal Frequency Division Multiplexing (FFH-OFDM) communication system which divides all of the available frequency bands into a plurality of sub-carrier bands and includes a plurality of sub-channels each including at least one sub-carrier band. The apparatus includes: a Fast Frequency Hopping (FFH) unit for allocating input data to a number of selected sub-carriers from among the plurality of sub-carriers and for performing fast frequency hopping in accordance with a fast frequency hopping pattern to generate FFH signals, wherein one or more pieces of data comprise the input data and each of the one or more pieces of data is allocated to one of the selected sub-carriers; a Fast Fourier Transform (FFT) unit for performing FFT on FFH signals; a controller for inserting null data into remaining sub-carriers, the remaining sub-carriers comprising sub-carriers other than the selected sub-carriers; a first Inverse Fast Fourier Transform (IFFT) unit for performing IFFT on both the selected sub-carriers comprising the input data and the remaining sub-carriers comprising the inserted null data to generate first IFFT signals; and a transmitter for transmitting the first IFFT signals.
摘要:
A transmission/reception method and apparatus in an Orthogonal Frequency Division Multiplexing (OFDM)-based wireless communication system are provided, in which a data transmitter adaptively selects a multiplexing scheme according to a code rate of the transmission packet or an effective SNR of a wireless channel for a corresponding terminal, when transmitting a packet data channel. The adaptive multiplexing scheme is equal in concept to a scheme of adaptively implementing unitary precoding. The unitary precoded multiplexing includes Orthogonal Frequency code Domain Multiplexing (OFCDM), Fast Fourier Transform-Spread-OFDM (FFT-S-OFDM), Fast Frequency Hopping-OFDM (FFH-OFDM), and the like. The method and apparatus adaptively selects the multiplexing scheme and transmits/receives data using the selected multiplexing scheme, thereby improving reception performance of the packet data.
摘要:
An apparatus for transmitting data in a frequency division multiple access based communication system is disclosed. The apparatus includes a symbol block generator for generating a symbol block in a predetermined symbol block period within one TTI when control information to be transmitted exists in the TTI, an FFT unit for performing FFT on the symbol block, and an IFFT unit for performing IFFT on signals output from the FFT unit and then transmitting the signals. The symbol block includes the control information and data to be transmitted. The TTI includes multiple symbol block periods.