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:
A method and apparatus for changing a Transmit Time Interval (TTI) based on a Hybrid Automatic Repeat Request (HARQ) process in a code division multiple access (CDMA) communication system that supports a packet data service through an Enhanced Uplink Dedicated transport Channel (E-DCH). According to the method and apparatus, a data transmission/reception is performed in a manner that a TTI change signal is received, the actual time point of TTI change is calculated based on the TTI change signal and the HARQ process of the previous TTI, and the TTI is changed at the calculated time point of TTI change.
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:
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 transmitter and receiver for fast frequency hopping based on a cyclic frequency hopping pattern in an orthogonal frequency division multiplexing system. The transmitter outputs a transmission signal vector having a plurality of samples. In the receiver, a first Fast Fourier Transform (FFT) processor transforms a first received signal vector into a second received signal vector of a frequency domain by using FFT. An equalizer multiplies the received signal vector by an inverse matrix of a channel matrix representing characteristics of a channel from the transmitter to the receiver. A modified IFFT processor transforms output of the equalizer by using IFFT, and multiplies IFFT outputs of a last stage of the modified IFFT processor by predetermined gains associated with the cyclic frequency hopping pattern of the transmitter. A second FFT processor transforms output of the modified IFFT processor by using FFT to output a recovered received signal vector.
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 performs inter-subband hopping on a resource unit for a User Equipment (UE) on a frequency axis along which at least two subbands are defined, at each predetermined hopping time, determines whether to turn on or off mirroring in a subband having the hopped resource unit on a cell basis at the each hopping time, selects a resource unit by selectively mirroring the hopped unit according to the determination, and allocates the selected resource unit to the UE.
摘要:
A method and apparatus for transmitting/receiving a Random Access Channel (RACH) signal in a communication system. A User Equipment (UE) selects one of Contention Resolution (CR) channels allocated for collision detection, and transmits the selected CR channel and a connection request message to an Evolved Node B (E-NB), and receives a response signal from the E-NB. The UE transmits the RACH signal, if a collision indicator is included in the response signal. The E-NB receives from each of UEs a connection request message and a CR channel, decodes the connection request message, and detects a collision between the UEs using the CR channel. The E-NB generates a response signal to the connection request message according to the decoding result, generates a collision indicator according to the collision detection result, and transmits to the UEs at least one of the generated response signal, the generated collision indicator, and a unique ID of a corresponding UE.
摘要:
A method and apparatus for changing a Transmit Time Interval (TTI) based on a Hybrid Automatic Repeat Request (HARQ) process in a code division multiple access (CDMA) communication system that supports a packet data service through an Enhanced Uplink Dedicated transport Channel (E-DCH). According to the method and apparatus, a data transmission/reception is performed in a manner that a TTI change signal is received, the actual time point of TTI change is calculated based on the TTI change signal and the HARQ process of the previous TTI, and the TTI is changed at the calculated time point of TTI change.
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 performs inter-subband hopping on a resource unit for a User Equipment (UE) on a frequency axis along which at least two subbands are defined, at each predetermined hopping time, determines whether to turn on or off mirroring in a subband having the hopped resource unit on a cell basis at the each hopping time, selects a resource unit by selectively mirroring the hopped unit according to the determination, and allocates the selected resource unit to the UE.
摘要:
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.