CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the U.S. national phase of PCT Application PCT/CN2018/104118 filed on Sep. 5, 2018, which claims the benefit and priority of Chinese Application No. 201710805104.3, filed on Sep. 8, 2017, the disclosures of which are incorporated in their entireties by reference herein.

TECHNICAL FIELD

The present disclosure relates to the technical field of communication applications, and in particular to a reference signal transmission method, a reference signal transmission device, a base station and a user equipment.

BACKGROUND

Phase noise comes from local oscillators in a transmitter and a receiver, and may affect transmission of multi-carrier signals. Especially in the high frequency band (above 6 GHz), influence of the phase noise is more serious, and thus it is necessary to perform phase noise compensation for received signals to ensure the system performance. By introducing a phase tracking reference signal (PTRS) at a transmitting end, phase changes caused by phase noise can be tracked, thereby ensuring that a receiver can estimate the phase noise of the link and compensate the influence of the phase noise.

In the new radio (NR) system, PTRS is transmitted in UE-scheduled frequency band, and may be mapped every one physical resource block (PRB), every two PRBs or every four PRBs, depending on varied frequency domain density. In the PRB including PTRS, each PTRS port is mapped to at least one subcarrier. Each PTRS port corresponds to a group of demodulation reference signal (DMRS) ports, hereinafter referred to as group correspondence. Each DMRS port within the group is affected by the same phase noise source, and this PTRS port is used to compensate for the phase noise of each DMRS port within the group. If there are multiple phase noise sources, multiple PTRS ports are required.

Similar to DMRS, PTRS also needs to be pre-coded for transmission. To compensate for the influence of phase noise, the precoding used by the PTRS is related to the precoding used by the group of DMRS ports corresponding to this PTRS port. Meanwhile, in order to ensure the compensation accuracy, the PTRS should be mapped to the subcarrier where the corresponding DMRS port group is located. Currently, one implementation manner is to pre-define that PTRS port uses a precoding used by a fixed DMRS port in a DMRS port group corresponding to the PTRS port and is mapped to a subcarrier where the DMRS port is located, which is hereinafter referred to as a port correspondence. This fixed DMRS port may be a DMRS port with the smallest index in the group. However, there is no corresponding solution about how to map a PTRS port to a subcarrier where a DMRS port associated with the PTRS port is located.

SUMMARY

An object of the present disclosure is to provide a reference signal transmission method, a reference signal transmission device, a base station and a user equipment, which can solve the problem that there is no corresponding solution about how to map a PTRS port to a subcarrier where a DMRS port associated with the PTRS port is located.

In order to achieve the above object, the present disclosure provides a reference signal transmission method, applied to a base station, including: implicitly or explicitly indicating to a user equipment (UE), position information of a target subcarrier for mapping a target phase tracking reference signal (PTRS) port, among subcarriers occupied by a target demodulation reference signal (DMRS) port; wherein the target DMRS port is a DMRS port associated with the target PTRS port.

The above reference signal transmission method further includes: transmitting a PTRS to the UE on the target subcarrier.

The explicitly indicating to the UE, the position information of the target subcarrier for mapping the PTRS port, among subcarriers occupied by the target DMRS port, includes: transmitting the position information to the UE by signaling; wherein the position information includes: offset information of a preset reference subcarrier corresponding to the target DMRS port relative to the target subcarrier.

Before the step of indicating to the UE, the position information of the target subcarrier for mapping the PTRS port, among subcarriers occupied by the target DMRS port, the method further includes: selecting the target subcarrier for mapping the PTRS port from the subcarriers occupied by the target DMRS port; and determining offset information of the target subcarrier relative to the preset reference subcarrier.

The implicitly indicating to the UE, the position information of the target subcarrier for mapping the PTRS port, among subcarriers occupied by the target DMRS port, includes: indicating the position information to the UE by predefinition; wherein the position information includes: position of a subcarrier for mapping the PTRS port among subcarriers occupied by each DMRS port; or, offset information of a subcarrier for mapping the PTRS port among subcarriers occupied by each DMRS port relative to a preset reference subcarrier corresponding to the each DMRS port.

The each DMRS port is a port in a preset DMRS ports group; the DMRS ports in the same preset DMRS ports group occupy the same subcarriers, and the DMRS ports in different preset DMRS ports groups occupy different subcarriers.

In order to achieve the above object, the present disclosure provides a reference signal transmission method, applied to a user equipment (UE), including: obtaining position information of a target subcarrier implicitly or explicitly indicated by a base station; wherein the target subcarrier is a subcarrier for mapping a target phase tracking reference signal (PTRS) port, among subcarriers occupied by a target demodulation reference signal (DMRS) port, and the target DMRS port is a DMRS port associated with the target PTRS port; and determining a target subcarrier according to the position information.

The above reference signal transmission method further includes: obtaining PTRS on the target subcarrier and performing phase noise estimation according to the PTRS.

The step of determining a target subcarrier according to the position information, includes: determining a target DMRS port associated with the target PTRS port; and according to the position information, determining the target subcarrier from subcarriers occupied by the target DMRS port.

The obtaining position information of a target subcarrier explicitly indicated by a base station, includes: obtaining the position information transmitted by the base station via signaling; wherein the position information includes: offset information of a preset reference subcarrier corresponding to the target DMRS port relative to the target subcarrier.

The obtaining position information of a target subcarrier implicitly indicated by a base station, includes: obtaining the position information of the target subcarrier by predefinition; wherein the position information includes: position of a subcarrier for mapping the PTRS port among subcarriers occupied by each DMRS port; or, offset information of a subcarrier for mapping the PTRS port among subcarriers occupied by each DMRS port relative to a preset reference subcarrier corresponding to the each DMRS port.

The each DMRS port is a port in a preset DMRS ports group; the DMRS ports in the same preset DMRS ports group occupy the same subcarriers, and the DMRS ports in different preset DMRS ports groups occupy different subcarriers.

In order to achieve the above object, the present disclosure provides a base station including: a transceiver, a memory, a processor, and a computer program stored on the memory and executable on the processor; wherein the processor executes the computer program to implement the following steps: implicitly or explicitly indicating to a user equipment (UE), position information of a target subcarrier for mapping a target phase tracking reference signal (PTRS) port, among subcarriers occupied by a target demodulation reference signal (DMRS) port; wherein the target DMRS port is a DMRS port associated with the target PTRS port.

The processor executes the computer program to further implement the following steps: transmitting a PTRS to the UE on the target subcarrier through the transceiver.

The processor executes the computer program to further implement the following steps: transmitting the position information to the UE by signaling through the transceiver; wherein the position information includes: offset information of a preset reference subcarrier corresponding to the target DMRS port relative to the target subcarrier.

The processor executes the computer program to further implement the following steps: selecting the target subcarrier for mapping the PTRS port from the subcarriers occupied by the target DMRS port; and determining offset information of the target subcarrier relative to the preset reference subcarrier.

The processor executes the computer program to further implement the following steps: indicating the position information to the UE by predefinition; wherein the position information includes: position of a subcarrier for mapping the PTRS port among subcarriers occupied by each DMRS port; or, offset information of a subcarrier for mapping the PTRS port among subcarriers occupied by each DMRS port relative to a preset reference subcarrier corresponding to the each DMRS port.

The each DMRS port is a port in a preset DMRS ports group; the DMRS ports in the same preset DMRS ports group occupy the same subcarriers, and the DMRS ports in different preset DMRS ports groups occupy different subcarriers.

In order to achieve the above object, the present disclosure provides a computer readable storage medium including a computer program stored thereon; wherein the computer program is executed by a processor to implement the following steps: implicitly or explicitly indicating to a user equipment (UE), position information of a target subcarrier for mapping a target phase tracking reference signal (PTRS) port, among subcarriers occupied by a target demodulation reference signal (DMRS) port; wherein the target DMRS port is a DMRS port associated with the target PTRS port.

In order to achieve the above object, the present disclosure provides a user equipment (UE) including: a transceiver, a memory, a processor, and a computer program stored on the memory and executable on the processor; wherein the processor executes the computer program to implement the following steps: obtaining position information of a target subcarrier implicitly or explicitly indicated by a base station; wherein the target subcarrier is a subcarrier for mapping a target phase tracking reference signal (PTRS) port, among subcarriers occupied by a target demodulation reference signal (DMRS) port, and the target DMRS port is a DMRS port associated with the target PTRS port; and determining a target subcarrier according to the position information.

The processor executes the computer program to further implement the following steps: obtaining PTRS on the target subcarrier and performing phase noise estimation according to the PTRS.

The processor executes the computer program to further implement the following steps: determining a target DMRS port associated with the target PTRS port; and according to the position information, determining the target subcarrier from subcarriers occupied by the target DMRS port.

The processor executes the computer program to further implement the following steps: obtaining the position information transmitted by the base station via signaling through the transceiver; wherein the position information includes: offset information of a preset reference subcarrier corresponding to the target DMRS port relative to the target subcarrier.

The processor executes the computer program to further implement the following steps: obtaining the position information of the target subcarrier by predefinition; wherein the position information includes: position of a subcarrier for mapping the PTRS port among subcarriers occupied by each DMRS port; or, offset information of a subcarrier for mapping the PTRS port among subcarriers occupied by each DMRS port relative to a preset reference subcarrier corresponding to the each DMRS port.

The each DMRS port is a port in a preset DMRS ports group; the DMRS ports in the same preset DMRS ports group occupy the same subcarriers, and the DMRS ports in different preset DMRS ports groups occupy different subcarriers.

In order to achieve the above object, the present disclosure provides a computer readable storage medium including a computer program stored thereon; wherein the computer program is executed by a processor to implement the following steps: obtaining position information of a target subcarrier implicitly or explicitly indicated by a base station; wherein the target subcarrier is a subcarrier for mapping a target phase tracking reference signal (PTRS) port, among subcarriers occupied by a target demodulation reference signal (DMRS) port, and the target DMRS port is a DMRS port associated with the target PTRS port; and determining a target subcarrier according to the position information.

In order to achieve the above object, the present disclosure provides a reference signal transmission device, applied to a base station, including: an indication module configured to, implicitly or explicitly indicate to a user equipment (UE), position information of a target subcarrier for mapping a target phase tracking reference signal (PTRS) port, among subcarriers occupied by a target demodulation reference signal (DMRS) port; wherein the target DMRS port is a DMRS port associated with the target PTRS port.

The indication module includes: a first indication submodule configured to transmit the position information to the UE by signaling; wherein the position information includes: offset information of a preset reference subcarrier corresponding to the target DMRS port relative to the target subcarrier.

The indication module includes: a second indication submodule configured to indicate the position information to the UE by predefinition; wherein the position information includes: position of a subcarrier for mapping the PTRS port among subcarriers occupied by each DMRS port; or, offset information of a subcarrier for mapping the PTRS port among subcarriers occupied by each DMRS port relative to a preset reference subcarrier corresponding to the each DMRS port.

The each DMRS port is a port in a preset DMRS ports group; the DMRS ports in the same preset DMRS ports group occupy the same subcarriers, and the DMRS ports in different preset DMRS ports groups occupy different subcarriers.

In order to achieve the above object, the present disclosure provides a reference signal transmission device, applied to a user equipment (UE), including: an obtaining module configured to obtain position information of a target subcarrier implicitly or explicitly indicated by a base station; wherein the target subcarrier is a subcarrier for mapping a target phase tracking reference signal (PTRS) port, among subcarriers occupied by a target demodulation reference signal (DMRS) port, and the target DMRS port is a DMRS port associated with the target PTRS port; and a determining module configured to determine the target subcarrier according to the position information.

The obtaining module includes: a first obtaining submodule configured to obtain the position information transmitted by the base station via signaling; wherein the position information includes: offset information of a preset reference subcarrier corresponding to the target DMRS port relative to the target subcarrier.

The obtaining module includes: a second obtaining submodule configured to obtain the position information of the target subcarrier by predefinition; wherein the position information includes: position of a subcarrier for mapping the PTRS port among subcarriers occupied by each DMRS port; or, offset information of a subcarrier for mapping the PTRS port among subcarriers occupied by each DMRS port relative to a preset reference subcarrier corresponding to the each DMRS port.

The each DMRS port is a port in a preset DMRS ports group; the DMRS ports in the same preset DMRS ports group occupy the same subcarriers, and the DMRS ports in different preset DMRS ports groups occupy different subcarriers.

The embodiments of the present disclosure have the following beneficial effects:

According to technical solutions of the embodiments of the present disclosure, the position information of the target subcarrier for mapping the PTRS port, among subcarriers occupied by the target DMRS port, is implicitly or explicitly indicated to the UE, so that the UE can determine the target subcarrier according to the position information and then obtains PTRS transmitted by the base station on the target subcarrier, thereby achieving the purpose of transmitting PTRS according to the position information and preventing different PTRS ports from being mapped to the same subcarrier and then effectively ensuring orthogonality between different PTRS ports.

