Patent Description:
In an existing wireless communications network, fewer operating frequency bands with a frequency range below <NUM> are available, and increasing communication requirements cannot be met. In a next-generation wireless communications network (for example, <NUM>), an operating frequency band of a communications system is above <NUM>. Therefore, the next-generation wireless communications network has a significant characteristic of a high-frequency communications system, thereby readily implementing a high throughput. However, compared with the existing wireless communications network, the next-generation wireless communications network operating in a range above <NUM> will suffer severer intermediate radio frequency distortion, especially impact caused by a phase noise (phase noise, PN). A higher phase noise level causes greater impact of a common phase error (Common Phase Error, CPE). In the prior art, a demodulation reference signal (Demodulation reference signal, DMRS) and a phase tracking reference signal (Phase tracking reference signal, PTRS) (also referred to as a phase compensation reference signal (Phase compensation Reference Signal, PCRS)) are provided to jointly complete channel estimation, phase noise estimation, and data demodulation. In the prior art, PTRSs are consecutive in time domain and frequency division is applied to a plurality of ports in frequency domain, and the ports are fixed. When data bandwidth is large, a relatively large quantity of subcarriers are occupied and resource overheads are relatively high. In addition, in different scenarios, for example, in different phase noise levels and moving speeds, a design with fixed time and frequency density lacks flexibility.

Therefore, how to flexibly configure a PTRS, reduce a quantity of subcarriers occupied by the PTRS, reduce overheads of the PTRS, and improve spectral efficiency is an urgent problem to be resolved.

In the paper "<NPL>, some agreements on reference signaling for phase tracking for CP-OFDM waveform are discussed. In particular, regarding precoder of PT-RS, it is suggested that the PT-RS shares one antenna port of DMRS. In that regard, the strongest antenna port is selected to transmit the PT-RS.

In the paper "<NPL>, reference signaling for phase tracking in the NR context is discussed. In the paper it is disclosed that, in order to guarantee robust and high-quality CPE estimation and compensation for each different oscillator source, orthogonal PT-RS resources should be allocated to different oscillator sources. The number of orthogonal PT-RS ports required depends on whether multiple DM-RS ports share the same oscillator or not.

In the paper "<NPL>, reference signaling for phase tracking is generally discussed. Among others, the paper is concerned with forward compatibility and port multiplexing regarding PT-RS is discussed.

In the paper "<NPL>, reference signaling enabling phase tracking for CP-OFDM waveform is discussed. It is disclosed that UE-specific configuring of PTRS is preferred considering the PTRS flexibility.

<CIT> discloses methods, systems, and devices for wireless communication. A user equipment (UE) may report a phase-noise compensation reference signal (PCRS) configuration to a base station to enable per-UE PCRS signaling. For example, a UE may operate in a wireless communications system using carrier frequencies greater than <NUM>, which may be affected by phase noise. The UE may accordingly determine a PCRS configuration based on a capability to receive signals. The PCRS configuration may include a resource mapping for one or more PCRS, a number of PCRS ports used for PCRS, a multiplexing scheme for one or more PCRS ports, or the UE's phase noise estimation capability. The UE may then transmit a reporting message including the PCRS configuration to a base station. The base station may use the PCRS configuration for PCRS transmissions to the UE.

This application provides wireless communication methods, a network device, and a terminal device according to the attached claims, so that the network device can provide the terminal device with an optimal port configuration for a phase tracking reference signal, and a phase tracking reference signal port can be flexibly configured for different terminals under different channel conditions, thereby reducing overheads of the phase tracking reference signal while ensuring phase noise error compensation performance, and improving spectral efficiency.

<FIG> is a schematic diagram of a communications system <NUM> according to an example for a better understanding. As shown in <FIG>, the communications system <NUM> includes a network device <NUM>. The network device <NUM> may include a plurality of antennas, for example, antennas <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>. In addition, the network device <NUM> may additionally include a transmitter chain and a receiver chain. A person of ordinary skill in the art may understand that the transmitter chain and the receiver chain each may include a plurality of components (for example, a processor, a modulator, a multiplexer, a demodulator, a demultiplexer, or an antenna) related to signal sending and receiving.

The network device <NUM> may communicate with a plurality of terminal devices (for example, a terminal device <NUM> and a terminal device <NUM>). However, it may be understood that the network device <NUM> may communicate with any quantity of terminal devices similar to the terminal device <NUM> or <NUM>.

As shown in <FIG>, the terminal device <NUM> communicates with the antennas <NUM> and <NUM>. The antennas <NUM> and <NUM> send information to the terminal device <NUM> by using a forward link <NUM>, and receive information from the terminal device <NUM> by using a reverse link <NUM>. In addition, the terminal device <NUM> communicates with the antennas <NUM> and <NUM>. The antennas <NUM> and <NUM> send information to the terminal device <NUM> by using a forward link <NUM> and receive information from the terminal device <NUM> by using a reverse link <NUM>.

For example, in a frequency division duplex (Frequency Division Duplex, FDD) system, the forward link <NUM> may use a frequency band different from that used by the reverse link <NUM>, and the forward link <NUM> may use a frequency band different from that used by the reverse link <NUM>. For another example, in a time division duplex (Time Division Duplex, TDD) system and a full duplex (Full Duplex, FD) system, the forward link <NUM> and the reverse link <NUM> may use a same frequency band, and the forward link <NUM> and the reverse link <NUM> may use a same frequency band.

Each antenna (or an antenna group including a plurality of antennas) and/or area that is designed for communication is referred to as a sector of the network device <NUM>. For example, the antenna group may be designed to communicate with a terminal device in a sector of coverage of the network device <NUM>. In a process in which the network device <NUM> separately communicates with the terminal devices <NUM> and <NUM> by using the forward links <NUM> and <NUM>, a transmit antenna of the network device <NUM> may improve signal-to-noise ratios of the forward links <NUM> and <NUM> through beamforming. In addition, compared with a manner in which a network device sends signals to all terminal devices within coverage of the network device by using a single antenna, when the network device <NUM> sends, through beamforming, signals to the terminal devices <NUM> and <NUM> that are randomly distributed within related coverage, less interference is caused to a mobile device in a neighboring cell.

Within a given time, the network device <NUM>, the terminal device <NUM>, or the terminal device <NUM> may be a wireless communications sending apparatus and/or a wireless communications receiving apparatus. When sending data, the wireless communications sending apparatus may encode the data for transmission. Specifically, the wireless communications sending apparatus may obtain (for example, generate, receive from another communications apparatus, or store in a memory) a specific quantity of data bits that need to be sent to the wireless communications receiving apparatus through a channel. The data bits may be included in a transport block (or a plurality of transport blocks) of data, and the transport block may be segmented to generate a plurality of code blocks.

In addition, the communications system <NUM> may be a public land mobile network (Public Land Mobile Network, PLMN), or another network. <FIG> is a simplified schematic diagram of an example. The system may further include other network devices that are not shown in <FIG>.

Optionally, in this embodiment of this application, the network device may be a device, for example, a base station or a base station controller, that communicates with a terminal device. Each network device may provide communication coverage for a specific geographic area, and can communicate with a terminal device (for example, UE) located within the coverage (a cell). The network device may support communication protocols of different standards, or may support different communication modes. For example, the network device may be a base transceiver station (Base Transceiver Station, BTS) in a GSM or a CDMA system, may be a NodeB (NodeB, NB) in a WCDMA system, or may be an evolved NodeB (Evolutional NodeB, eNB or eNodeB) in an LTE system, or a radio controller in a cloud radio access network (Cloud Radio Access Network, CRAN). Alternatively, the network device may be a network device in a future <NUM> network, for example, a gNB, a small cell, a micro cell, or a TRP (transmission reception point, transmission reception point), or may be a relay station, an access point, a network device in a future evolved public land mobile network (Public Land Mobile Network, PLMN), or the like. Optionally, in this embodiment of this application, the terminal device may be an access terminal, user equipment (User Equipment, UE), a subscriber unit, a subscriber station, a mobile station, a mobile console, a remote station, a remote terminal, a mobile terminal, a user terminal, a terminal, a wireless communications device, a user agent, or a user apparatus. The access terminal may be a cellular phone, a cordless phone, a session initiation protocol (Session Initiation Protocol, SIP) phone, a wireless local loop (Wireless Local Loop, WLL) station, a personal digital assistant (Personal Digital Assistant, PDA), a handheld device having a wireless communication function, a computing device or another processing device connected to a wireless modem, an in-vehicle device, a wearable device, a terminal device in internet of things, a virtual reality device, a terminal device in a future <NUM> network, a terminal device in a future evolved public land mobile network (Public Land Mobile Network, PLMN), or the like.

The wireless communication method and the device provided in the embodiments of this application can be applied to a terminal device, and the terminal device includes a hardware layer, an operating system layer running above the hardware layer, and an application layer running above the operating system layer. The hardware layer includes hardware such as a central processing unit (Central Processing Unit, CPU), a memory management unit (Memory Management Unit, MMU), and a memory (which is also referred to as a main memory). The operating system may be any one or more computer operating systems that implement service processing by using a process (Process), for example, the Linux operating system, the UNIX operating system, the Android operating system, the iOS operating system, or the Windows operating system. The application layer includes applications such as a browser, a contact list, word processing software, and instant messaging software.

In addition, various aspects or features of this application may be implemented as a method, an apparatus, or a product that uses standard programming and/or engineering technologies. The term "product" used in this application covers a computer program that may be accessed from any computer readable component, carrier, or medium. For example, the computer-readable medium may include but is not limited to a magnetic storage device (for example, a hard disk, a floppy disk, or a magnetic tape), an optical disc (for example, a compact disc (Compact Disc, CD), or a digital versatile disc (Digital Versatile Disc, DVD)), a smart card and a flash memory component (for example, an erasable programmable read-only memory (Erasable Programmable Read-Only Memory, EPROM), a card, a stick, or a key drive). In addition, various storage media described in this specification may indicate one or more devices and/or other machine-readable media that are used to store information. The term "machine-readable media" may include but is not limited to various media that can store, contain and/or carry an instruction and/or data.

To better understand this application, the following describes this application with reference to <FIG> by using a system same as or similar to the system shown in <FIG> as an example.

<FIG> is a schematic flowchart of a wireless communication method <NUM> according to this application. As shown in <FIG>, the method <NUM> includes the following content.

In process <NUM>, a terminal device determines at information about sharing a local oscillator by a plurality of transceiver units, and optionally further determines information about phase noise errors measured on a plurality of phase tracking reference signal ports, isolation between a plurality of channels used to carry phase tracking reference signals, and status information of the channels used to carry the phase tracking reference signals.

Optionally, that a terminal device determines at least one of information about sharing a local oscillator by a plurality of transceiver units, information about phase noise errors measured on a plurality of phase tracking reference signal ports, isolation between a plurality of channels used to carry phase tracking reference signals, and status information of the channels used to carry the phase tracking reference signals includes: determining, based on a status of sharing a local oscillator unit by the plurality of transceiver units, the information about sharing a local oscillator by the plurality of transceiver units.

Specifically, the transceiver units (Transceiver Units, TxRU) are hardware components of the terminal device, and include an analog-to-digital converter, a local oscillator, a frequency mixer, a filter, a power amplifier, and the like. The transceiver units include a plurality of receiving units or a plurality of sending units. The status of sharing a local oscillator by the transceiver units means a status of sharing a local oscillator by the plurality of receiving units or a status of sharing a local oscillator by the plurality of sending units.

Optionally, the determining, based on a status of sharing a local oscillator by the plurality of transceiver units, the information about sharing a local oscillator by the plurality of transceiver units includes: determining, based on a status of sharing a local oscillator by a plurality of inherent transceiver units in the terminal device, the information about sharing a local oscillator by the plurality of transceiver units.

Specifically, determining the status of sharing a local oscillator by the transceiver units may be an inherent capability of the terminal device, and the status of sharing a local oscillator by the transceiver units is determined during manufacturing of the terminal device.

This application provides at least one of the following methods to help implement mapping between a PTRS and a DMRS:
The terminal device indicates, based on a capability of the terminal device, whether receiving/sending units of the terminal device share a local oscillator.

Alternatively, the terminal device reports whether phase noise errors measured by the terminal device on PTRS ports are the same.

Optionally, sending, to a network device, the at least one of the information about sharing a local oscillator by the plurality of transceiver units, the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals includes: sending, to the network device, a quantity of transceiver units driven by each local oscillator unit of the terminal device; or sending, to the network device, indication information that the plurality of transceiver units share a local oscillator.

Specifically, the terminal device sends, to the network device, the quantity of transceiver units driven by each local oscillator unit of the terminal device. For example, the terminal device has four receiving units that are respectively a receiving unit <NUM>, a receiving unit <NUM>, a receiving unit <NUM>, and a receiving unit <NUM>. If the terminal device sends numbers <NUM> and <NUM> to the network device, it indicates that the receiving unit <NUM>, the receiving unit <NUM>, and the receiving unit <NUM> share a local oscillator.

The terminal device may further indicate, by using the indication information, the status of sharing a local oscillator by the plurality of transceiver units, as shown in Table <NUM>.

It can be learned from Table <NUM> that four receiving units of the transceiver units are respectively a receiving unit <NUM>, a receiving unit <NUM>, a receiving unit <NUM>, and a receiving unit <NUM>, where a number <NUM> in the table indicates that a local oscillator unit is shared, and a number <NUM> indicates that a local oscillator unit is not shared. It can be learned from the table that the receiving unit <NUM> and the receiving unit <NUM> share a local oscillator, and the receiving unit <NUM> and the receiving unit <NUM> share a local oscillator.

It should be understood that the indication information that a local oscillator is shared can be represented in another manner. The two manners listed in this application are merely examples, and are not limited thereto.

Optionally, the determining at least one of information about sharing a local oscillator by a plurality of transceiver units, information about phase noise errors measured on a plurality of phase tracking reference signal ports, isolation between a plurality of channels used to carry phase tracking reference signals, and status information of the channels used to carry the phase tracking reference signals includes: estimating, on a downlink channel based on a second reference signal on each of the plurality of channels used to carry the phase tracking reference signals, the isolation between the plurality of channels used to carry the phase tracking reference signals.

Optionally, the determining at least one of information about sharing a local oscillator by a plurality of transceiver units, information about phase noise errors measured on a plurality of phase tracking reference signal ports, isolation between a plurality of channels used to carry phase tracking reference signals, and status information of the channels used to carry the phase tracking reference signals includes: determining, based on a second reference signal of each of the plurality of channels used to carry the phase tracking reference signals, the isolation between the plurality of channels used to carry the phase tracking reference signals; and sending, to the network device, the isolation between the channels corresponding to a plurality of second reference signals.

Optionally, the second reference signal is a demodulation reference signal and/or a channel state information-reference signal (Channel State Information-Reference Signal, CSI-RS) and/or a mobility reference signal (Mobility Reference Signal, MRS) and/or a beam reference signal (Beam Reference Signal, BRS) and/or a beam refinement reference signal (Beam Refinement Reference Signal, BRRS) and/or a beam management reference signal (Beam Management Reference Signal, BMRS).

Port configuration information, requested by the terminal device, of a phase tracking reference signal is determined based on the information about sharing a local oscillator by the plurality of transceiver units, and optionally further on the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals; and the port configuration information, requested by the terminal device, of the phase tracking reference signal is sent to the network device.

In process <NUM>, the terminal device sends, to the network device, the at least one of the information about sharing a local oscillator by the plurality of transceiver units, the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals.

Optionally, after accessing the network device, the terminal device demodulates data based on a default configuration, and feeds back, on a feasible uplink resource, the information about sharing a local oscillator by the plurality of transceiver units.

Specifically, after accessing the network device, the terminal device demodulates the data based on the default configuration, and feeds back, on an uplink resource such as a random access signal or an uplink reference signal, the information about sharing a local oscillator by the plurality of transceiver units.

Optionally, if no default configuration is specified by the network device, when accessing the network device, the terminal device sends the information about sharing a local oscillator of the terminal device, where the information about sharing a local oscillator is used by the network device to determine port configuration information of the PTRS.

Optionally, first information is sent to the network device, where the first information is used by the terminal device to request a resource from the network device, and the resource is used by the terminal device to send, to the network device, the port configuration information, requested by the terminal device, of the phase tracking reference signal; and acknowledgment information sent by the network device for the first information is received, where the acknowledgment information is used to indicate the resource on which the terminal device sends the port configuration information, required by the terminal device, of the phase tracking reference signal.

Optionally, second information sent by the network device is received, where the second information is used to instruct the terminal device to feed back, to the network device, the port configuration information, requested by the terminal device, of the phase tracking reference signal.

In process <NUM>, the network device obtains at least one of the information about sharing a local oscillator by the plurality of transceiver units of the terminal device, isolation between the plurality of channels used to carry the phase tracking reference signals, and status information of the channels used to carry the phase tracking reference signals.

Optionally, that the network device obtains at least one of the information that is about sharing a local oscillator by the plurality of transceiver units and that is sent by the terminal device, the information that is about the phase noise errors measured on the plurality of phase tracking reference signal ports and that is sent by the terminal device, isolation between the plurality of channels used to carry the phase tracking reference signals, and status information of the channels used to carry the phase tracking reference signals includes: The network device receives the at least one of the information that is about sharing a local oscillator by the plurality of transceiver units and that is sent by the terminal device, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals.

Determining port configuration information of the phase tracking reference signal based on the information about sharing a local oscillator by the plurality of transceiver units, and optionally further on the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals includes: determining a quantity of phase tracking reference signal ports based on the information about the phase noise errors measured on the plurality of phase tracking reference signal ports.

Optionally, the determining a quantity of phase tracking reference signal ports based on the information about the phase noise errors measured on the plurality of phase tracking reference signal ports includes: if values of the phase noise errors measured on the plurality of phase tracking reference signal ports are less than a first threshold, determining that there is one phase tracking reference signal port.

Optionally, that the network device obtains at least one of the information about sharing a local oscillator by the plurality of transceiver units of the terminal device, the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, isolation between the plurality of channels used to carry the phase tracking reference signals, and status information of the channels used to carry the phase tracking reference signals includes: The network device receives the information that is about sharing a local oscillator by the plurality of transceiver units and that is sent by the terminal device, and the network device determines, on a network device side, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals.

Optionally, when the network device estimates isolation between a plurality of downlink channels used to carry phase tracking reference signals, the network device estimates the isolation between the plurality of downlink channels based on first reference signals on a plurality of uplink channels.

Optionally, the first reference signal is one or more of the following reference signals: a sounding reference signal (Sounding Reference Signal, SRS), and a demodulation reference signal (DMRS).

Optionally, determining, based on the isolation between the plurality of channels used to carry the phase tracking reference signals, an orthogonal multiplexing manner applied to the plurality of ports that are configured to send the phase tracking reference signals or an orthogonal multiplexing manner applied to the phase tracking reference signal and data includes: estimating, based on a second reference signal on each of the plurality of channels used to carry the phase tracking reference signals, the isolation between the plurality of channels used to carry the phase tracking reference signals; and
determining, based on the estimated isolation between the plurality of channels used to carry the phase tracking reference signals, the orthogonal multiplexing manner applied to the plurality of ports that are configured to send the phase tracking reference signals or the orthogonal multiplexing manner applied to the phase tracking reference signal and data.

Optionally, the determining, based on the estimated isolation between the plurality of channels used to carry the phase tracking reference signals, the orthogonal multiplexing manner applied to the plurality of ports that are configured to send the phase tracking reference signals includes: when the isolation between the plurality of channels used to carry the phase tracking reference signals meets a preset condition, applying non-orthogonal multiplexing to the plurality of ports of the phase tracking reference signals or applying non-orthogonal multiplexing to the phase tracking reference signal and data.

Optionally, the network device receives isolation, sent by the terminal device, of the plurality of downlink channels used to carry the phase tracking reference signals, where the terminal device estimates, based on the second reference signal on each of the plurality of channels used to carry the phase tracking reference signals, the isolation between the plurality of channels used to carry the phase tracking reference signals.

In process <NUM>, the network device determines the port configuration information of the phase tracking reference signal based on the at least one of the information about sharing a local oscillator by the plurality of transceiver units, the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals.

Optionally, after the terminal device accesses the network device, the network device sends data based on a default PTRS configuration.

Optionally, that the network device determines the port configuration information of the phase tracking reference signal based on the at least one of the information about sharing a local oscillator by the plurality of transceiver units, the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals includes: determining a quantity of phase tracking reference signal ports based on the information about sharing a local oscillator by the plurality of transceiver units.

Optionally, the determining a quantity of phase tracking reference signal ports based on the information about sharing a local oscillator by the plurality of transceiver units includes: if the plurality of transceiver units share a local oscillator, determining that there is one phase tracking reference signal port for the plurality of transceiver units.

Optionally, that the network device determines the port configuration information of the phase tracking reference signal based on the at least one of the information about sharing a local oscillator by the plurality of transceiver units, the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals includes:
determining a quantity of phase tracking reference signal ports based on the information about the phase noise errors measured on the plurality of phase tracking reference signal ports.

Optionally, the determining a quantity of phase tracking reference signal ports based on the information about the phase noise errors measured on the plurality of phase tracking reference signal ports includes: if the values of the phase noise errors measured on the plurality of phase tracking reference signal ports are less than the first threshold, determining that there is one phase tracking reference signal port.

Optionally, the determining the port configuration information of the phase tracking reference signal based on the at least one of the information about sharing a local oscillator by the plurality of transceiver units, the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals includes: determining, based on the isolation between the plurality of channels used to carry the phase tracking reference signals, the orthogonal multiplexing manner applied to the plurality of ports that are configured to send the phase tracking reference signals or the orthogonal multiplexing manner applied to the phase tracking reference signal and data.

Optionally, the determining, based on the isolation between the plurality of channels used to carry the phase tracking reference signals, the orthogonal multiplexing manner applied to the plurality of ports that are configured to send the phase tracking reference signals or the orthogonal multiplexing manner applied to the phase tracking reference signal and data includes: estimating, based on a first reference signal on each of the plurality of channels used to carry the phase tracking reference signals, the isolation between the plurality of channels used to carry the phase tracking reference signals; and determining, based on the estimated isolation between the plurality of channels used to carry the phase tracking reference signals, the orthogonal multiplexing manner applied to the plurality of ports that are configured to send the phase tracking reference signals or the orthogonal multiplexing manner applied to the phase tracking reference signal and data.

For example, in a <NUM>*<NUM> single-user MIMO mode, a network device sends a first reference signal <NUM> and a first reference signal <NUM> on two channels respectively. When isolation between the channels is relatively good, a terminal device receives the first reference signal <NUM> and the first reference signal <NUM> on the corresponding channels respectively. However, if the isolation between the channels is poor, the terminal device receives the first reference signal <NUM> on a channel on which the first reference signal <NUM> is expected to be received or receives the first reference signal <NUM> on a channel on which the first reference signal <NUM> is expected to be received. This indicates that interference exists between the channels. Isolation between channels may be determined based on first reference signals on the channels. If the isolation between the channels meets a preset condition, non-orthogonal multiplexing is applied to a PTRS port and a DMRS port.

Optionally, the determining, based on the estimated isolation between the plurality of channels used to carry the phase tracking reference signals, the orthogonal multiplexing manner applied to the plurality of ports that are configured to send the phase tracking reference signals includes: when the isolation between the plurality of channels used to carry the phase tracking reference signals meets the preset condition, applying non-orthogonal multiplexing to the plurality of ports of the phase tracking reference signals or applying non-orthogonal multiplexing to the phase tracking reference signal and data.

For example, <FIG> shows several configurations of phase tracking reference signal ports in a <NUM>*<NUM> single-user MIMO mode. Different configurations are applicable to different scenarios. A configuration c is the prior art and is a default configuration. To be specific, both a DMRS and a PTRS are configured at each transport layer, a quantity of DMRS ports is equal to a quantity of PTRS ports, and orthogonality is applied to the DMRS port and the PTRS port.

In the <NUM>*<NUM> single-user MIMO mode, there are two receiving units and two sending units. The two receiving units are used as an example. If the two receiving units share a local oscillator, it indicates that phase noise errors of the two receiving units may be estimated based on one PTRS, and the PTRS is sent to the terminal device by using one port. In this case, a quantity of PTRS ports is reduced, so that a resource block used to transmit a PTRS at a transport layer can be used to transmit data. As shown in a configuration a, there is one PTRS port, and non-orthogonality is applied to the PTRS port and data.

If the two receiving units do not share a local oscillator, it indicates that the two receiving units have different phase noise errors, and the phase noise errors of signals cannot be estimated based on one PTRS. Therefore, PTRSs are sent to the terminal device by using two ports. If isolation between channels for sending the PTRSs is relatively good and signals on the two channels do not interfere with each other, a non-orthogonal manner may be used on the PTRS ports. As shown in a configuration b, there are two PTRS ports, a quantity of PTRS ports is equal to a quantity of DMRS ports, and non-orthogonality is applied to the PTRS ports.

In a configuration d, there is one PTRS port, and orthogonality is applied to the PTRS port and data. In a configuration e, a quantity of PTRS ports is equal to that of DMRS ports, the PTRS ports are in a time division mode, and non-orthogonality is applied to the PTRS ports and data. Optionally, the determining the port configuration information of the phase tracking reference signal based on the at least one of the information about sharing a local oscillator by the plurality of transceiver units, the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals includes: determining, based on the status information of the channels used to carry the phase tracking reference signals, a mapping relationship between the phase tracking reference signal and a first reference signal.

Specifically, the network device may determine the mapping relationship between the phase tracking reference signal and the first reference signal based on the status information of the channels, such as a signal-to-noise ratio and channel quality. If signal-to-noise ratios of the channels are relatively high, a PTRS port may be mapped to a transport layer at which the first reference signal is transmitted.

Specifically, a mapping relationship between the DMRS port and the PTRS port may be indicated by using a quasi co-location (Quasi Co-Located, QCL) relationship. The QCL relationship or the mapping relationship may be represented in a format of Table <NUM> or Table <NUM>. The mapping relationship, for example, QCL, between the PTRS and the DMRS can be configured by using RRC signaling.

In each of Table <NUM> and Table <NUM>, there are four DMRS ports and two PTRS ports, where the four DMRS ports are respectively N1, N2, N3, and N4, and the two PTRS ports are respectively mapped to layers at which the N1 port and the N3 port are located.

Optionally, because the channel status changes in real time, the port configuration information of the PTRS needs to be updated based on the channel status in a periodic or quasi-static manner or through triggering. The triggering may be initiated by the network device or the terminal device. Optionally, the first reference signal is a demodulation reference signal.

Optionally, after the port configuration information of the phase tracking reference signal is sent to the terminal device, the method further includes:
sending the phase tracking reference signal to the terminal device based on the port configuration information of the phase tracking reference signal.

Optionally, the port configuration information of the phase tracking reference signal is determined based on the at least one of the port configuration information, requested by the terminal device, of the phase tracking reference signal, the isolation, estimated on a network side, of the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals.

Optionally, when the port configuration information that is of the phase tracking reference signal and that is determined based on the isolation between the plurality of channels used to carry the phase tracking reference signals or the status information of the channels used to carry the phase tracking reference signals is the same as the port configuration information, requested by the terminal device, of the phase tracking reference signal, acknowledgment information is sent to the terminal device.

Alternatively, when the port configuration information that is of the phase tracking reference signal and that is determined based on the isolation between the plurality of channels used to carry the phase tracking reference signals or the status information of the channels used to carry the phase tracking reference signals is different from the port configuration information, requested by the terminal device, of the phase tracking reference signal, the port configuration information, determined by the network device, of the phase tracking reference signal is sent to the terminal device.

Optionally, before the port configuration information, requested by the terminal device, of the phase tracking reference signal, the isolation between the plurality of channels used to carry the phase tracking reference signals, or the status information of the channels used to carry the phase tracking reference signals is obtained, the method further includes: receiving the first information sent by the terminal device, where the first information is used by the terminal device to request the resource from the network device, and the resource is used by the terminal device to send, to the network device, the port configuration information, requested by the terminal device, of the phase tracking reference signal; and sending the acknowledgment information to the terminal device for the first information, where the acknowledgment information is used to indicate the resource on which the terminal device sends the port configuration information, required by the terminal device, of the phase tracking reference signal.

Optionally, before the port configuration information, requested by the terminal device, of the phase tracking reference signal, the isolation between the plurality of channels used to carry the phase tracking reference signals, or the status information of the channels used to carry the phase tracking reference signals is obtained, the method further includes: sending the second information to the terminal device, where the second information is used to instruct the terminal device to feed back, to the network device, the port configuration information, requested by the terminal device, of the phase tracking reference signal.

Optionally, the network device sends third indication information to the terminal device, where the third indication information is used to indicate an effective time, sent by the network device to the terminal device, of the port configuration information of the phase tracking reference signal, and the effective time may be a period of time after the terminal device receives the port configuration information of the phase tracking reference signal, and the time may be expressed in slots and/or subframes and/or frames.

Optionally, when the quantity of ports for sending the phase tracking reference signals is less than a quantity of ports for sending first reference signals, and non-orthogonal multiplexing is applied to the phase tracking reference signal and data, quantities of valid resource elements used to transmit data are different at a plurality of transport layers, and the method further includes: when one transport block is mapped to a plurality of transport layers, matching a corresponding quantity of bits for each code block, where a quantity of code blocks is obtained by dividing the transport block based on a predetermined value; obtaining a quantity of quadrature amplitude modulation symbols of each code block; and performing, at the plurality of transport layers, layer mapping on the quadrature amplitude modulation symbols of the transport block.

Optionally, there is one port for the phase tracking reference signal and one port for the first reference signal at each of the plurality of transport layers. When the quantity of ports for sending the phase tracking reference signals is less than the quantity of ports for sending the first reference signals, and non-orthogonal multiplexing is applied to the phase tracking reference signal and data, quantities of resource elements occupied by the phase tracking reference signal are different at each of the plurality of transport layers. Therefore, quantities of valid resource elements used to transmit data are different at each of the plurality of transport layers. The method further includes: determining, in rate matching, a quantity of bits of each code block obtained after encoding; and performing layer mapping.

When one transport block is mapped to a plurality of transport layers, a corresponding quantity of bits is matched for each code block, and a quantity of code blocks is obtained by dividing the transport block based on a predetermined value, and is determined by using Formula (<NUM>) and Formula (<NUM>).

Herein, G represents a total quantity of bits available for a current transport block, and G' represents a total quantity of resource elements on average at each layer. When a transmit diversity technology is used, NL = <NUM>. Otherwise, NL represents a quantity of layers to which the current transport block is mapped, C represents a quantity of code blocks obtained by dividing the current transport block, Qm represent a modulation order, and Rl and Rp respectively represent an integer part and a fractional part of a result of G'modC.

Herein, Ei represents a quantity of transmitted bits corresponding to each code block.

The layer mapping means to perform, at the plurality of transport layers, layer mapping on the quadrature amplitude modulation symbols of the transport block based on a quantity of quadrature amplitude modulation symbols of each code block. Layer mapping is performed on the quadrature amplitude modulation symbols of the transport block for the plurality of transport layers according to Formula (<NUM>) and Formula (<NUM>): <MAT> <MAT>.

Herein, <MAT> represents a quantity of quadrature amplitude modulation symbols of a kth transport block, <MAT> represents a quantity of quadrature amplitude modulation symbols mapped by the kth transport block at a layer i, and <MAT> represents a quantity of valid resource elements at the layer i.

In process <NUM>, the network device sends the port configuration information of the phase tracking reference signal to the terminal device.

Optionally, the port configuration information of the phase tracking reference signal may be configured by the network device for the terminal device by using RRC signaling.

In process <NUM>, the terminal device receives the port configuration information, sent by the network device, of the phase tracking reference signal.

Optionally, the terminal device receives, based on the port configuration information of the phase tracking reference signal, the phase tracking reference signal sent by the network device.

Therefore, in this application, the network device determines, based on the information about sharing a local oscillator by the plurality of transceiver units of the terminal device, the quantity of ports for sending the PTRSs; determines, based on the isolation between the plurality of channels used to carry the phase tracking reference signals, an orthogonal multiplexing manner applied to the PTRS ports and the DMRS ports or a multiplexing manner applied to the PTRS ports and data; and determines a transport layer of the PTRS based on the status information of the channels used to carry the phase tracking reference signals, so that the port configuration information of the PTRS is determined. In this way, a PTRS port is flexibly configured, and a quantity of ports for sending PTRSs can be reduced. Therefore, a quantity of subcarriers occupied by the PTRSs is reduced, and resource overheads are reduced.

In process <NUM>, a terminal device determines information about sharing a local oscillator by a plurality of communications units, and optionally further information about phase noise errors measured on a plurality of phase tracking reference signal ports, isolation between a plurality of channels used to carry phase tracking reference signals, and status information of the channels used to carry the phase tracking reference signals.

Optionally, the determining at least one of information about sharing a local oscillator by a plurality of transceiver units, information about phase noise errors measured on a plurality of phase tracking reference signal ports, isolation between a plurality of channels used to carry phase tracking reference signals, and status information of the channels used to carry the phase tracking reference signals includes: determining, based on a status of sharing a local oscillator unit by the plurality of transceiver units, the information about sharing a local oscillator by the plurality of transceiver units.

According to the invention, determining a quantity of phase tracking reference signal ports based on the information about sharing a local oscillator by the plurality of transceiver units includes: if the plurality of transceiver units share a local oscillator, determining that there is one phase tracking reference signal port for the plurality of transceiver units.

In process <NUM>, the terminal device determines port configuration information, requested from a network device, of a phase tracking reference signal based on the information about sharing a local oscillator by the plurality of communications units, and optionally further based on the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals.

The determining a quantity of phase tracking reference signal ports based on the information about sharing a local oscillator by the plurality of transceiver units includes: if the plurality of transceiver units share a local oscillator, determining that there is one phase tracking reference signal port for the plurality of transceiver units.

Optionally, the determining port configuration information of a phase tracking reference signal based on the at least one of the information about sharing a local oscillator by the plurality of transceiver units, the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals includes: determining, based on the isolation between the plurality of channels used to carry the phase tracking reference signals, an orthogonal multiplexing manner applied to the plurality of ports that are configured to send the phase tracking reference signals or an orthogonal multiplexing manner applied to the phase tracking reference signal and data.

Optionally, the determining, based on the isolation between the plurality of channels used to carry the phase tracking reference signals, an orthogonal multiplexing manner applied to the plurality of ports that are configured to send the phase tracking reference signals or an orthogonal multiplexing manner applied to the phase tracking reference signal and data includes:.

Optionally, the determining port configuration information of a phase tracking reference signal based on the at least one of the information about sharing a local oscillator by the plurality of transceiver units, the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals includes: determining, based on the status information of the channels used to carry the phase tracking reference signals, a mapping relationship between the phase tracking reference signal and a first reference signal.

Optionally, the first reference signal is a demodulation reference signal.

In process <NUM>, the terminal device sends the requested port configuration information of the phase tracking reference signal to the network device.

Optionally, first information is sent to the network device, where the first information is used by the terminal device to request a resource from the network device, and the resource is used by the terminal device to send, to the network device, the port configuration information, requested by the terminal device, of the phase tracking reference signal.

Acknowledgment information sent by the network device for the first information is received, where the acknowledgment information is used to indicate the resource on which the terminal device sends the port configuration information, required by the terminal device, of the phase tracking reference signal.

In process <NUM>, the network device receives the requested port configuration information, sent by the terminal device, of the phase tracking reference signal.

In process <NUM>, the network device determines port configuration information of the phase tracking reference signal.

Optionally, the network device determines, based on at least one of isolation between the plurality of channels used to carry the phase tracking reference signals, and status information of the channels used to carry the phase tracking reference signals, whether to accept the port configuration information, requested by the terminal device, of the phase tracking reference signal, where the isolation and the status information are obtained on a network side.

Specifically, if the isolation, obtained by the network device, between the plurality of channels used to carry the phase tracking reference signals and the status information, obtained by the network device, of the channels used to carry the phase tracking reference signals are consistent with the port configuration information requested by the terminal device, the network device accepts the port configuration information, requested by the terminal device, of the phase tracking reference signal. Otherwise, the port configuration information, requested by the terminal device, of the phase tracking reference signal is corrected.

Optionally, if the network device accepts the port configuration information, requested by the terminal device, of the phase tracking reference signal, the port configuration information, sent to the terminal device, of the phase tracking reference signal is acknowledgment information. If the network device rejects the port configuration information, requested by the terminal device, of the phase tracking reference signal, the network device sends the port configuration information, determined by the network device, of the phase tracking reference signal to the terminal device.

Optionally, the phase tracking reference signal sent by the network device is received based on the port configuration information of the phase tracking reference signal.

Therefore, in this application, the terminal device determines, based on the information about sharing a local oscillator by the plurality of transceiver units, the quantity of ports for sending the PTRSs; determines, based on the isolation between the plurality of channels used to carry the phase tracking reference signals, an orthogonal multiplexing manner applied to the PTRS ports and DMRS ports or a multiplexing manner applied to the PTRS ports and data; and determines a transport layer of the PTRS based on the status information of the channels used to carry the phase tracking reference signals, so that the port configuration information of the PTRS is determined and the port configuration information of the phase tracking reference signal is sent to the network device. In this way, a PTRS port is flexibly configured, and a quantity of ports for sending PTRSs can be reduced. Therefore, a quantity of subcarriers occupied by the PTRSs is reduced, and resource overheads are reduced.

<FIG> is a schematic block diagram of a network device <NUM> according to this application. As shown in <FIG>, the network device includes:.

Optionally, the obtaining module <NUM>, the determining module <NUM>, and the sending module <NUM> are configured to perform operations of the wireless communication method <NUM> in the embodiment of this application. For brevity, details are not described herein again.

<FIG> is a schematic block diagram of a terminal device <NUM> according to this application. As shown in <FIG>, the terminal device includes:.

Optionally, the determining module <NUM> and the sending module <NUM> are configured to perform operations of the wireless communication method <NUM> in the embodiment of this application. For brevity, details are not described herein again.

The determining module <NUM> of the terminal device <NUM> in this application is further configured to determine at least one of information about sharing a local oscillator by a plurality of communications units, information about phase noise errors measured on a plurality of phase tracking reference signal ports, isolation between a plurality of channels used to carry phase tracking reference signals, and status information of the channels used to carry the phase tracking reference signals.

The determining module <NUM> is further configured to determine port configuration information, requested from a network device, of a phase tracking reference signal based on the at least one of the information about sharing a local oscillator by the plurality of communications units, the information about the phase noise errors measured on the plurality of phase tracking reference signal ports, the isolation between the plurality of channels used to carry the phase tracking reference signals, and the status information of the channels used to carry the phase tracking reference signals.

The sending module <NUM> is further configured to send the requested port configuration information of the phase tracking reference signal to the network device.

The network device and the terminal device described above are respectively corresponding to the network device and the terminal device in the method embodiments, and corresponding processes are performed by the corresponding modules. For details, refer to the corresponding method embodiments.

<FIG> is a schematic block diagram of a communications apparatus <NUM> according to this application. The communications apparatus <NUM> includes:.

When the code is executed, the processor <NUM> implements operations in the method <NUM> or the method <NUM>. For brevity, details are not described herein again. In this case, the communications apparatus <NUM> may be a network device or a terminal device. The transceiver <NUM> is specifically configured to receive and send signals under driving of the processor <NUM>.

The communications apparatus <NUM> may be the network device or the terminal device described above, and perform an operation of the determining module. The transceiver may include a transmitter and/or a receiver, and perform corresponding processes of the sending module and the receiving module respectively.

A person of ordinary skill in the art may be aware that, the units and algorithm steps in the examples described with reference to the embodiments disclosed in this specification may be implemented by electronic hardware or a combination of computer software and electronic hardware. A person skilled in the art may use different methods to implement the described functions for each particular application, but it should not be considered that such implementation goes beyond the scope of this application.

It may be clearly understood by a person skilled in the art that, for the purpose of convenient and brief description, for a detailed working process of the system, apparatus, and unit, refer to a corresponding process in the method embodiments.

Claim 1:
A wireless communication method, comprising:
determining, by a terminal device, port configuration information, to be reported to a network device, of a phase tracking reference signal; and
sending (<NUM>), by the terminal device, the port configuration information of the phase tracking reference signal to the network device, wherein the port configuration information of the phase tracking reference signal comprises a quantity of phase tracking reference signal ports determined based on information about sharing a local oscillator by a plurality of transceiver units of the terminal device, wherein if a quantity of local oscillator units of the plurality of transceiver units is one, the quantity of phase tracking reference signal ports is one.