A method for operating a transmitting device to communicate with a receiving device is described herein. The method includes the step of the transmitting device selecting a root index value from a set of root index values. The method further includes the step of the transmitting device generating a frequency domain Constant Amplitude Zero Auto-Correlation sequence based on the selected root index value. The method further includes the step of the transmitting device modulating the Constant Amplitude Zero Auto-Correlation sequence by a pseudo-noise sequence. The method further includes the step of the transmitting device generating an Orthogonal Frequency Division Multiplexing symbol, wherein the frequency domain Constant Amplitude Zero Auto-Correlation sequence modulated by the pseudo-noise sequence defines subcarrier values for the Orthogonal Frequency Division Multiplexing symbol. The method further includes the step of the transmitting device transmitting the Orthogonal Frequency Division Multiplexing symbol as an initial Orthogonal Frequency Division Multiplexing symbol of a preamble of a frame to the receiving device.

A method for operating a transmitting device to communicate with a receiving device is described herein. The method includes the step of the transmitting device selecting a root index value from a set of root index values. The method further includes the step of the transmitting device generating a frequency domain Constant Amplitude Zero Auto-Correlation sequence based on the selected root index value. The method further includes the step of the transmitting device modulating the Constant Amplitude Zero Auto-Correlation sequence by a pseudo-noise sequence. The method further includes the step of the transmitting device generating an Orthogonal Frequency Division Multiplexing symbol, wherein the frequency domain Constant Amplitude Zero Auto-Correlation sequence modulated by the pseudo-noise sequence defines subcarrier values for the Orthogonal Frequency Division Multiplexing symbol. The method further includes the step of the transmitting device transmitting the Orthogonal Frequency Division Multiplexing symbol as an initial Orthogonal Frequency Division Multiplexing symbol of a preamble of a frame to the receiving device.

Techniques are disclosed relating to channel sounding. In some embodiments a transmitter transmits a periodic CAZAC sequence beginning at a point in time that corresponds to a timing signal (e.g., a pulse-per-second signal). In some embodiments, a receiver waits to begin processing received sequences for a time interval corresponding to the length of the CAZAC sequence, where the time interval begins at the same time as the timing signal. This may avoid a need for timing synchronization prior to processing, reduce processing and latency in receiver implementations, and may allow determination of a TOA as well as a channel impulse response estimate by correlating a received cyclically-shifted CAZAC sequence with a local version of the transmitted CAZAC sequence.

Disclosed is a data transmission method in a mobile communication system. The data transmission method through a code sequence in a mobile communication system includes grouping input data streams into a plurality of blocks consisting of at least one bit so as to map each block to a corresponding signature sequence, multiplying a signature sequence stream, to which the plurality of blocks are mapped, by a specific code sequence, and transmitting the signature sequence stream multiplied by the specific code sequence to a receiver.

A method and a base station for receiving uplink control signals in a wireless communication system are described. The base station receives a first uplink control channel in a mixed resource block from a first user equipment. The mixed resource block includes a plurality of subcarriers. The base station receives a second uplink control channel in the mixed resource block from a second user equipment. The first uplink control channel is identified by a first cyclic shift value. The second uplink control channel is identified by a second cyclic shift value that is different from the first cyclic shift value. The first uplink control channel carries a Hybrid Automatic Repeat Request (HARQ) acknowledgement/negative acknowledgement (ACK/NACK) of the first user equipment. The second uplink control channel carries a channel quality indicator (CQI) for the second user equipment and a HARQ ACK/NACK of the second user equipment.

A wireless communication terminal apparatus wherein even when a SC-FDMA signal is divided into a plurality of clusters and the plurality of clusters are then mapped to respective discontinuous frequency bands (when C-SC-FDMA is used), the improvement effect of system throughput can be maintained, while the user throughput can be improved. In the apparatus, a DFT unit (210) subjects a symbol sequence of time domain to a DFT process, thereby generating signals of frequency domain. A setting unit (211) divides the signals input from the DFT unit (210) into a plurality of clusters according to a cluster pattern that is in accordance with an MCS set, an encoding size, or the number of Ranks occurring during MIMO transmissions, which is indicated in those signals input, and then maps the plurality of clusters to the respective ones of a plurality of discontinuous frequency resources, thereby setting a constellation of the plurality of clusters in the frequency domain.

A terminal that communicates with a base station monitors a physical downlink control channel allocated in a physical downlink control channel region and an enhanced physical downlink control channel allocated in a physical downlink shared channel region different from the physical downlink control channel region. If the enhanced physical downlink control channel is detected, the terminal reports response information via a physical uplink control channel resource corresponding to the resource in which the enhanced physical downlink control channel was detected.

A radio transmission system based on a frequency divisional multiplexing method is described, wherein a transmit symbol comprises a plurality of data symbols assigned to at least two subcarriers. The information of symbols of one time slot is spread across the data symbols of subcarrier of the time slot to produce a transmit symbol being more robust to frequency selective channels.

Disclosed is a data transmission method in a mobile communication system. The data transmission method through a code sequence in a mobile communication system includes grouping input data streams into a plurality of blocks consisting of at least one bit so as to map each block to a corresponding signature sequence, multiplying a signature sequence stream, to which the plurality of blocks are mapped, by a specific code sequence, and transmitting the signature sequence stream multiplied by the specific code sequence to a receiver.

A base station is provided for receiving an acknowledgement or negative acknowledgement (ACK/NACK) signal, including a transmitting unit configured to transmit a control signal using one or a plurality of CCE(s). The base station also includes a receiving unit configured to receive an ACK/NACK signal, the ACK/NACK signal being multiplied by an orthogonal sequence, by a sequence defined by a cyclic shift, and by either a first value or a second value, wherein the first value rotates a constellation of the ACK/NACK signal by 0 degrees and the second value rotates the constellation of the ACK/NACK signal by N degrees, which is different from 0 degrees.