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.

This application discloses a wireless communication method, a wireless communications apparatus, and a wireless communications system. An example wireless communication method includes: receiving, by a terminal, indication information of uplink data transmission from a base station; determining, by the terminal, a base sequence configuration of a reference signal sequence corresponding to the modulation scheme of the uplink data transmission, and generating a dedicated demodulation reference signal based on the determined base sequence configuration of the reference signal sequence, where the modulation scheme of the uplink data transmission is one of a plurality of modulation schemes supported by the terminal, the plurality of modulation schemes include at least π/2 binary phase shift keying (BPSK), and a base sequence configuration of a reference signal sequence corresponding to the π/2 BPSK is different from a base sequence configuration of a reference signal sequence corresponding to another modulation scheme in the plurality of modulation schemes.

Embodiments provide a method for generating a random access channel ZC sequence, and an apparatus. A method for generating a random access channel ZC sequence includes: generating, by a base station, notification signaling, where the notification signaling instructs user equipment (UE) to generate a random access ZC sequence by using a second restricted set in a random access set; and sending, by the base station, the notification signaling to the UE, so that the UE generates the random access ZC sequence by using the second restricted set, where the random access set includes an unrestricted set, a first restricted set, and the second restricted set; and the second restricted set is a random access set that the UE needs to use when a Doppler frequency shift of the UE is greater than or equal to a first predetermined value.

Embodiments provide a method for generating a random access channel ZC sequence, and an apparatus. A method for generating a random access channel ZC sequence includes: generating, by a base station, notification signaling, where the notification signaling instructs user equipment (UE) to generate a random access ZC sequence by using a second restricted set in a random access set; and sending, by the base station, the notification signaling to the UE, so that the UE generates the random access ZC sequence by using the second restricted set, where the random access set includes an unrestricted set, a first restricted set, and the second restricted set; and the second restricted set is a random access set that the UE needs to use when a Doppler frequency shift of the UE is greater than or equal to a first predetermined value.

An eNB may determine a root for a sequence to be included in a signal to a UE. The eNB may generate a generalized Chu sequence based on the root and scramble the generalized Chu sequence using a pseudorandom sequence that is common to a plurality of eNBs. The eNB may transmit the scrambled generalized Chu sequence to indicate the beginning of a downlink transmission. The UE may receive this scrambled generalized Chu sequence and determine if a beginning of a downlink transmission from a serving eNB based on the received generalized Chu sequence and an expected generalized Chu sequence.

An eNB may determine a root for a sequence to be included in a signal to a UE. The eNB may generate a generalized Chu sequence based on the root and scramble the generalized Chu sequence using a pseudorandom sequence that is common to a plurality of eNBs. The eNB may transmit the scrambled generalized Chu sequence to indicate the beginning of a downlink transmission. The UE may receive this scrambled generalized Chu sequence and determine if a beginning of a downlink transmission from a serving eNB based on the received generalized Chu sequence and an expected generalized Chu sequence.

A network access node and a client device for generating and using cubic phase polynomial sequences (s.sub.i, s.sub.j) of length L with a third order coefficient value a.sub.3 belonging to the subset of sequences (S.sub.k) are described. The network access node transmits a control message to the client device, wherein the control message indicates the cyclical shift value N.sub.CS and the third order coefficient value a.sub.3. The client device receives the control message and determines a cubic polynomial phase sequence (s.sub.i) belonging to the subset of sequences (S.sub.k) based on the cyclical shift value N.sub.CS and the third order coefficient value a.sub.3. The client device thereafter transmits the determined cubic polynomial phase sequence (s.sub.i) as a random access preamble to the network access node.

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.