According to some embodiments, a method in a wireless receiver of compensating common phase error in a received wireless signal comprises receiving a first symbol of a wireless signal. The first symbol comprises a code division multiplexed demodulation reference signal (DM-RS) multiplexed with a length M orthogonal cover code, and a first code division multiplexed common phase error reference signal (CPE-RS) multiplexed with a length N orthogonal cover code, wherein N is less than or equal to M. The method further comprises determining M code points in the first symbol associated with a DM-RS; estimating a channel corresponding to the received wireless signal using the M code points associated with the DM-RS; estimating a first CPE-RS corresponding to the estimated channel using the first N code points of the M code points associated with the DM-RS; and compensating the estimated channel for phase error using the estimated first CPE-RS.

Provided are a method and a device for transmitting uplink data by using a non-orthogonal code multiple access scheme in a wireless communication system. Particularly, a terminal receives control information from a base station. The terminal selects a terminal-specific codeword or receives allocation information of the terminal-specific codeword on the basis of the control information. The terminal transmits uplink data by using the terminal-specific codeword. The terminal-specific codeword is determined as a codeword having a value with a low peak-to-average power ratio (PAPR), when the terminal is located on the outside of a cell. The terminal-specific codeword is determined as a codeword having a value with a high PAPR, when the terminal is located in the center of the cell.

The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system for supporting higher data rates beyond a 4th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. The present invention relates to a method and an apparatus for estimating an uplink channel of a base station in a wireless communication system, comprising the steps of: estimating a position of a wireless channel tap on the basis of a sounding reference signal (SRS) received from a terminal; determining an average power value of the wireless channel tap for each link between a transmitting antenna and a receiving antenna from and to which the SRS is transmitted; and estimating an effective channel frequency response (effective CFR) of a physical uplink shared channel (PUSCH) on the basis of the position of the wireless channel tap and the average power value of the wireless channel tap.

A radio communication apparatus includes spreading circuitry that spreads a response signal using a first set of orthogonal sequences to produce a spread response signal. Each orthogonal sequence in the first set has a first length. The spreading circuitry also spreads a reference signal using a second set of orthogonal sequences to produce a spread reference signal. Each orthogonal sequence in the second set has a second length that is shorter than the first length. A radio transmitter transmits the spread response signal and the spread reference signal.

Techniques for utilizing multiple carriers to substantially improve transmission capacity are described. For multi-carrier operation, a terminal receives an assignment of multiple forward link (FL) carriers and at least one reverse link (RL) carrier. The carriers may be arranged in at least one group, with each group including at least one FL carrier and one RL carrier. The terminal may receive packets on the FL carrier(s) in each group and may send acknowledgements for the received packets via the RL carrier in that group. The terminal may send channel quality indication (CQI) reports for the FL carrier(s) in each group via the RL carrier in that group. The terminal may also transmit data on the RL carrier(s). The terminal may send designated RL signaling (e.g., to originate a call) on a primary RL carrier and may receive designated FL signaling (e.g., for call setup) on a primary FL carrier.

When a plurality of terminals share the same resources in a wireless communication system, and when control information such as acknowledgement/negative acknowledgement (ACK/NAK) information or scheduling information is transmitted, a method of efficiently performing code division multiplexing (CDM) is required to distinguish the plurality of terminals. In particular, it is necessary to develop a method by which a code sequence of CDM can be selected and used according to each cell condition. Provided is a method of forming a signal in a wireless communication system in which a plurality of terminals commonly share frequency and time resources. The method includes the operations of receiving condition information in a cell; selecting one of a plurality of time domain orthogonal sequences having different lengths, according to the condition information; and allocating the selected time domain orthogonal sequence to a control signal symbol block.

An apparatus and method for transmission of a single-carrier waveform from multiple transmit antennas including both a reference signal and data in a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) symbol.

Methods, systems, and devices are disclosed for digital wireless communication, and more specifically, for the use of pilot sequences that improves performance of channel estimation. In one exemplary aspect, a method of wireless communication performed by a communication node is disclosed. The method includes determining, using a first index, a mask sequence from a plurality of pre-determined mask sequences, wherein the plurality of pre-determined mask sequences is determined based on permutations of values 1, 1, i, and i or permutations of values 1+i, or 1i, or 1+i, or 1i; determining a Walsh sequence using a second index, wherein the Wash sequence has a same length as the mask sequence; generating a pilot sequence by combining the mask sequence and the Walsh sequence; and performing a wireless transmission using the pilot sequence.

The present disclosure discloses an M-ary DCSK method based on chaotic shape-forming filtering. The method includes the following steps: at S1, parameters of a communication system are set; at S2, HP information and LP information to be sent in each time slot are prepared; at S3, the information to be sent is modulated; at S4, a chaotic carrier is generated through a chaotic shape-forming filter; at S5, a transmitted signal is prepared; at S6, down-carrier frequency and matched filter is performed to a received signal; at S7, the sampling of a maximum SNR point is performed to an output signal of a matched filter; at S8, the decision of high priority information bits is resumed; and at S9, the decision of low priority information bits is resumed.

A terminal apparatus includes circuitry and a transmitter. The circuitry, in operation, generates a reference signal using a cyclic shift value and an orthogonal sequence, which are associated with each other. The orthogonal sequence is one of two orthogonal sequences corresponding to a first orthogonal sequence [1, 1] and a second orthogonal sequence [1, 1]. The cyclic shift value is one of 12 cyclic shift values ranging from 0 to 11. The transmitter, in operation, transmits the reference signal multiplexed with a data signal. Two of the cyclic shift values having a difference of 6 are respectively associated with the two orthogonal sequences.