WO2024098901A1

WO2024098901A1 - Phase tracking reference signal mapping configuration and indication in wireless communication systems

Info

Publication number: WO2024098901A1
Application number: PCT/CN2023/115791
Authority: WO
Inventors: Meng MEI; Bo Gao; Yang Zhang; Ke YAO; Xiaolong Guo
Original assignee: Zte Corporation
Priority date: 2023-08-30
Filing date: 2023-08-30
Publication date: 2024-05-16

Abstract

Techniques are described for configuring and indicating a mapping between one or more phase tracking reference signal (PTRS) ports and one or more demodulation reference signal (DMRS) ports. An example wireless communication method includes receiving, by a wireless device from a network node, an indication for a single-carrier physical uplink shared channel (PUSCH) transmission comprising at least one phase tracking reference signal (PTRS) port and at least two demodulation reference signal (DMRS) ports, and performing, based on the indication, the single-carrier PUSCH transmission.

Description

PHASE TRACKING REFERENCE SIGNAL MAPPING CONFIGURATION AND INDICATION IN WIRELESS COMMUNICATION SYSTEMS

TECHNICAL FIELD

This disclosure is directed generally to digital wireless communications.

BACKGROUND

Mobile telecommunication technologies are moving the world toward an increasingly connected and networked society. In comparison with the existing wireless networks, next generation systems and wireless communication techniques will need to support a much wider range of use-case characteristics and provide a more complex and sophisticated range of access requirements and flexibilities.

Long-Term Evolution (LTE) is a standard for wireless communication for mobile devices and data terminals developed by 3rd Generation Partnership Project (3GPP) . LTE Advanced (LTE-A) is a wireless communication standard that enhances the LTE standard. The 5th generation of wireless system, known as 5G, advances the LTE and LTE-Awireless standards and is committed to supporting higher data-rates, large number of connections, ultra-low latency, high reliability and other emerging business needs.

SUMMARY

Methods, systems, and devices for configuring and indicating a phase tracking reference signal (PTRS) port mapping are disclosed. Embodiments of the disclosed technology provide additional associations between PTRS ports and demodulation reference signal (DMRS) ports, thereby improving phase tracking in wireless communications.

In an example aspect, a wireless communication method includes receiving, by a wireless device from a network node, an indication for a single-carrier physical uplink shared channel (PUSCH) transmission comprising at least one phase tracking reference signal (PTRS) port and at least two demodulation reference signal (DMRS) ports, and performing, based on the indication, the single-carrier PUSCH transmission.

In another example aspect, a wireless communication method includes configuring, by a network node, a single-carrier physical uplink shared channel (PUSCH) transmission comprising at least one phase tracking reference signal (PTRS) port and at least two demodulation reference signal (DMRS) ports, and transmitting, to a wireless device subsequent to the configuring, a wireless communication.

In yet another exemplary aspect, the above-described methods are embodied in the form of processor-executable code and stored in a non-transitory computer-readable storage medium. The code included in the computer readable storage medium when executed by a processor, causes the processor to implement the methods described in this patent document.

In yet another exemplary embodiment, a device that is configured or operable to perform the above-described methods is disclosed.

The above and other aspects and their implementations are described in greater detail in the drawings, the descriptions, and the claims.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows an example mapping pattern for two PTRS ports.

FIG. 2 shows an example mapping pattern using orthogonal cover codes (OCCs) of length 2 for two PTRS ports.

FIG. 3 shows a flowchart of an example method for wireless communications.

FIG. 4 shows a flowchart of another example method for wireless communications.

FIG. 5 shows an exemplary block diagram of a hardware platform that may be a part of a network device or a communication device.

FIG. 6 shows an example of wireless communication including a base station (BS) and user equipment (UE) based on some implementations of the disclosed technology.

DETAILED DESCRIPTION

In 5G NR, PUSCH is the physical uplink channel that carries user data. DMRS and PTRS are the reference signals associated with PUSCH. DMRS is used for channel estimation as part of coherent demodulation of PUSCH. To compensate for the common phase error (CPE) , 3GPP 5G NR introduced PTRS. Phase noise produced in local oscillators introduces a significant degradation at mmWave frequencies. It produces CPE and inter-carrier interference (ICI) . CPE leads to an identical rotation of a received symbol in each subcarrier. ICI leads to a loss of orthogonality between the subcarriers. PTRS is used mainly to estimate and minimize the effect of CPE on system performance.

In the 5G NR design for cyclic prefix–orthogonal frequency division multiplexing (CP-OFDM) , up to 2 PTRS ports and up to 1 DMRS port are supported, and an association between the PTRS port and the DMRS port is defined.

In the current specification, two bits are used for a PTRS-DMRS association in the downlink control information (DCI) field as shown in Table 1, Table 2 and Table 3. When a number of DMRS ports share one PTRS port, the two bits are used to indicate which DMRS port (s) is (are) associated with the one PTRS port.

Table 1: PTRS-DMRS association for UL PTRS port 0

As shown in Table 1, four DMRS ports share PTRS port 0, and the two bits indicate which scheduled DMRS port (of the four DMRS ports) is associated with PTRS port 0.

Table 2: PTRS-DMRS association for UL PTRS ports 0 and 1

As shown in Table 2, two PTRS ports are supported, and two DMRS ports share one PTRS port. Herein, the two bits are used to indicate the association of the DMRS ports and the two PTRS ports; a first bit is used to indicate which DMRS port is associated with PTRS port 0, and the second bit is used to indicate which DMRS port is associated with PTRS port 1.

In Table 1 and Table 2, the DMRS port in each table corresponds to one SRS resource indicator field and/or precoding information and the number of layers field. In Table 3, two SRS resource indicator fields and/or precoding information and the number of layers fields are supported, and each bit is used for a PTRS-DMRS association of the corresponding SRS resource indicator field and/or precoding information and the number of layers field.

Table 3: PTRS-DMRS association for UL PTRS port 0 or for the actual UL PT-RS port

For single-carrier PUSCH transmissions, e.g., Discrete Fourier Transform-Spread-Orthogonal Frequency Division Multiplexing (DFT-S-OFDM) , only one layer and one PTRS port are supported, and thus, there is no need to indicate an association between the PTRS and the DMRS. For a PTRS mapping, the PUSCH supports a number of sample groups, and each sample group supports a number of samples. For the sequence of PTRS, Table 4 shows the different lengths of orthogonal cover codes (OCCs) that are used for each PTRS group. Table 5 shows a PTRS symbol mapping, wherein the parameteris the scheduled bandwidth for the uplink transmission (expressed as a number of subcarriers) .

Table 4: The orthogonal sequence w (i)

Table 5: PTRS symbol mapping

As discussed above, for single-carrier PUSCH transmissions on the uplink, current systems only support one DMRS port. If PTRS is configured, the PTRS is associated with the one DMRS port. For NR, emerging base station and user equipment can support more than one layer for single-carrier PUSCH transmissions. Embodiments of the disclosed technology provide methods and systems for configuring mappings and indications for PTRS when single-carrier PUSCH transmissions are used with more than one layer.

The example headings for the various sections below are used to facilitate the understanding of the disclosed subject matter and do not limit the scope of the claimed subject matter in any way. Accordingly, one or more features of one example section can be combined with one or more features of another example section. Furthermore, 5G terminology is used for the sake of clarity of explanation, but the techniques disclosed in the present document are not limited to 5G technology only, and may be used in wireless systems that implemented other protocols.

Embodiment 1

In some embodiments, one PTRS port is supported, and is associated with one of multiple indicated DMRS ports for a single-carrier PUSCH transmission with one layer. In an example, the first DMRS port or the last DMRS port being associated with the one PTRS port is the default configuration. In another example, and for up to two DMRS ports, 1 bit in the downlink control information (DCI) field is used to indicate the association of the one PTRS port and the up to two DMRS ports, as shown in Table 1-1.

Table 1-1: PTRS-DMRS association for UL PTRS port

In an example, if two or more layers are supported, then at least 2 bit are needed, as shown in Table 1-2.

Table 1-2: PTRS-DMRS association for UL PTRS port 0

In some embodiments, the indication is enabled when the single-carrier PUSCH transmission is configured by the Radio Resource Control (RRC) , e.g., when transform precoding is enabled.

Embodiment 2

In some embodiments, two PTRS ports are supported for a single-carrier PUSCH transmission with at least two layers, and the two PTRS ports are associated with at least two DMRS ports. In an example, PTRS port #0 being associated with DMRS port #0, and PTRS port #1 being associated with DMRS port #1, is the default configuration. In another example, one bit in the DCI field is used to indicate which PTRS ports are associated with which one of the DMRS ports, as shown in Table 2-1.

Table 2-1: PTRS-DMRS association for UL PTRS port 0 and 1

In an example, if two or more layers are supported, then at least 2 bit are needed, as shown in Table 2-2.

Table 2-2: PTRS-DMRS association for UL PTRS ports 0 and 1

Embodiment 3

In some embodiments, for the mapping of PTRS ports and if a single-carrier PUSCH transmission with two layers is supported, two data layers are mapped on different frequency-domain resources, and the associated PTRS ports are also mapped on the related frequency-domain resources. However, if the two layers of the PUSCH are mapped on to the same resources, the two PTRS ports may be overlapped, and new mapping rules are introduced.

In some embodiments, and for time-division multiplexed (TDM) -based PTRS, different PTRS ports are mapped on to different OFDM symbols. In an example, the first PTRS port is mapped based on current mapping rules, and according to the time-domain density of the PTRS port and the symbols mapped to the DMRS.

In an example, the second PTRS is determined using a new rule to map the second DMRS port for single-carrier PUSCH transmissions, such as:

The set of time indices l for which the PTRS is transmitted is defined relative to the start of the PUSCH allocation, and is defined by:

1. Set i=0 and l_ref=1

2. If any symbol in the interval max (l_ref+ (i-1) L_PT-RS+1, l_ref) , ..., l_ref+iL_PT-RS overlaps with a symbol used for DMRS according to clause 6.4.1.1.3 of section 6.4.1.2.2.2 in 3GPP TS 38.211 V17.5.0.

–set i=1

–set l_ref to the symbol index after the DMRS symbol in case of a single-symbol DMRS and after the symbol index of the second DMRS symbol in case of a double-symbol DMRS

–repeat from step 2 as long as l_ref+iL_PTRS is inside the PTRS allocation

3. Add l_ref+iL_PTRS to the set of time indices for PTRS

4. Increment I by one

5. Repeat from step 2 as long as l_ref+iL_PTRS is inside the PTRS allocation, where L_PTRS∈ {1, 2} is provided by a higher-layer parameter.

In another example, the second PTRS is determined based on a sample offset, e.g., l in the above paragraphs with respect to the first PTRS port. For example, an offset of ‘1’ symbol after the symbol mapped to the first PTRS port results in the second PTRS port being mapped on the OFDM symbols after the OFDM symbols mapped to the first PTRS port. Alternatively, other offset values can be configured by RRC, or activated by the Medium Access Control (MAC) Control Element (CE) , or indicated by DCI.

Embodiment 4

In some embodiments, the scheduling bandwidth is the same for different transmission layers, and thus, the number of PTRS groups and number of samples per PTRS group are the same for different PTRS ports. For single-carrier PTRS, the maximum number of PTRS ports can be configured by RRC, the sample density for each PTRS can be configured by the same RRC parameter, i.e., one sample density configuration for all the PTRS ports, or the sample density can be configured independently for each PTRS port.

In some embodiments, different PTRS ports are mapped on different PTRS sample groups. As shown in Table 4-1, five kinds of sample groups and samples in each group combination are supported. Each PTRS port can be configured or indicated with any rows of the five cases. Alternatively, or additionally, the mapped PTRS ports can be configured or indicated with the same rows or different rows.

In an example, consider two PTRS ports with two sample groups and 2 samples in each sample group, as shown in FIG. 1. As shown therein, PTRS port 1 is mapped on the two sides of the samples of the first layer of the PUSCH, and for PTRS port 2, the two groups are mapped on samples in the second layer that are next to the sample groups corresponding to the sample groups for PTRS port 1. In order to reduce the interference between PTRS and data, an orthogonal mapping rule between data and PTRS can be used, i.e., the resource or subcarrier that is mapped with PTRS in the other layer should not be used for data. For the example shown in FIG. 1, for layer 1, only PTRS port 1 is mapped but the subcarriers that are used to map PTRS port 2 for layer 2 are not used for data mapping, and zero padding is used instead. The same rules for PTRS 2 and layer 2 mapping are used, as shown in FIG. 1.

In another example, the interference between PTRS and data is negligible, and zero padding is not used; instead, the corresponding subcarriers are used to map data.

In some embodiments, a sample offset or sample group offset is used to indicate the mapping of subcarriers for PTRS port 2. For example, the sample groups for PTRS port 2 are not mapped next to the subcarriers of PTRS port 1; instead, they are mapped on other subcarriers as indicated by the sample offset or the sample group offset.

In some embodiments, different multiplexing methods can be supported between sample groups. As shown in FIG. 1, the two groups between PTRS port 1 and PTRS port 2 are modulated or demodulated separately, and can be treated as being frequency-division multiplexed (FDM) or time-division multiplexed (TDM) . Similarly, and as shown in FIG. 2, the two groups between PTRS port 1 and PTRS port 2 can be modulated or demodulated as one combined group, and an orthogonal cover code (OCC) can be used.

In an example, different OCC used for different PTRS ports; if up to 2 PTRS ports are supported, an OCC with length 2 is used. In another example, an OCC of length 2 or length 4 is used in one sample group for one PTRS port. The OCC used between different sample groups can be interpreted as a first step of the OCC method, and the OCC used in one sample group for one PTRS port can be interpreted as a second step of the OCC method. The samples and PTRS groups can be mapped as shown in Table 4-1.

Table 4-1: Symbol mapping for the second PTRS

Embodiment 5

In some embodiments, and if the different PTRS ports are multiplexed among different PTRS sample groups, the total number of sample groups are doubled. Alternatively, if different PTRS ports are multiplexed among different PTRS samples in one group, the total number of samples in one sample group are doubled.

In an example, assume at least two samples are supported in one group for single PTRS port, and if 2 PTRS ports are supported, then at least four samples should be supported in one group. As shown in Table 5-1, only 4 samples in one PTRS group are supported; the first two samples are used for the first PTRS port and the other two samples are used for the other PTRS port. Herein, an OCC of length 2 is supported for each PTRS port. In this case, the two PTRS ports are modulated or demodulated separately by using an OCC of length 2, or an OCC with length 4 can be used for the 4 samples between the two PTRS ports. Alternatively, the two-step OCC method, described in Embodiment 4, is used between the two PTRS ports and the samples for each PTRS port.

Table 5-1: PTRS symbol mapping

In some embodiments, and in order to improve reliability, 4 samples for one PTRS port can be supported. For example, assume two PTRS groups such that the number of samples per PTRS group is 4 or 8. The first 4 samples are for the first PTRS port, and the other 4 samples are for the second PTRS port. An OCC with length 4 can be used for each PTRS port, and the two-step OCC method can be used for the two PTRS ports and the 4 samples for each PTRS port. Alternatively, an OCC with length 8 can be used for the 8 samples in one PTRS group, as shown in Table 5-2.

Table 5-2: The orthogonal sequence w (i)

Example methods and implementations of the disclosed technology

FIG. 3 shows a flowchart of an example wireless communication method 300. The method 300 includes, at operation 310, receiving, by a wireless device from a network node, an indication for a single-carrier PUSCH transmission comprising at least one PTRS port and at least two DMRS ports.

The method 300 includes, at operation 320, performing, based on the indication, the single-carrier PUSCH transmission.

FIG. 4 shows a flowchart of an example wireless communication method 400. The method 400 includes, at operation 410, configuring, by a network node, a single-carrier PUSCH transmission comprising at least one PTRS port and at least two DMRS ports.

The method 400 includes, at operation 420, transmitting, to a wireless device subsequent to the configuring, a wireless communication.

The disclosed embodiments provide, inter alia, the following technical solutions:

1. A wireless communication method, comprising receiving, by a wireless device from a network node, an indication for a single-carrier physical uplink shared channel (PUSCH) transmission comprising at least one phase tracking reference signal (PTRS) port and at least two demodulation reference signal (DMRS) ports; and performing, based on the indication, the single-carrier PUSCH transmission.

2. A wireless communication method, comprising configuring, by a network node, a single-carrier physical uplink shared channel (PUSCH) transmission comprising at least one phase tracking reference signal (PTRS) port and at least two demodulation reference signal (DMRS) ports; and transmitting, to a wireless device subsequent to the configuring, a wireless communication.

3. The method of solution 1 or 2, wherein the at least one PTRS port comprises one PTRS port. At least this solution is detailed in Embodiment 1.

4. The method of solution 3, wherein the one PTRS port is associated with a first DMRS port or a last DMRS port of the at least two DMRS ports.

5. The method of solution 3 or 4, wherein one bit in a downlink control information (DCI) field is used to indicate an association between the one PTRS port and up to two of the at least two DMRS ports.

6. The method of solution 1 or 2, wherein the at least one PTRS port comprises two PTRS ports.

7. The method of solution 6, wherein a first PTRS port of the two PTRS ports is associated with a first DMRS port of the at least two DMRS ports, and wherein a second PTRS port of the two PTRS ports is associated with a second DMRS port of the at least two DMRS ports. At least this solution is detailed in Embodiment 2.

8. The method of solution 6 or 7, wherein one bit in a downlink control information (DCI) field is used to indicate an association between the two PTRS ports and two DMRS ports of the at least two DMRS ports.

9. The method of any of solutions 6 to 8, wherein two bits in a downlink control information (DCI) field are used to indicate an association between the two PTRS ports and more than two DMRS ports of the at least two DMRS ports.

10. The method of any of solutions 6 to 9, wherein each of the two PTRS ports are mapped to a different orthogonal frequency division multiplexing (OFDM) symbol, a different PTRS group, or a different PTRS sample. At least this solution is detailed in Embodiment 3.

11. The method of solution 10, wherein a first PTRS port is mapped to a first OFDM symbol, and wherein a second PTRS port is mapped to a second OFDM symbol defined by a symbol offset from the first OFDM symbol.

12. The method of solution 11, wherein the symbol offset is indicated in a radio resource control (RRC) configuration, a medium access control (MAC) control element (CE) , a downlink control information (DCI) field.

13. The method of solution 11, wherein the symbol offset is set to a default value.

14. The method of solution 10, wherein a first PTRS port is mapped to a first PTRS group, and wherein a second PTRS port is mapped to a second PTRS group defined by a group offset from the first PTRS group.

15. The method of solution 14, wherein the group offset is indicated in a radio resource control (RRC) configuration, a medium access control (MAC) control element (CE) , or a downlink control information (DCI) field.

16. The method of solution 14, wherein the group offset is set to a default value.

17. The method of solution 10, wherein a first PTRS port is mapped to a first PTRS sample, and wherein a second PTRS port is mapped to a second PTRS sample defined by a sample offset from the first PTRS sample.

18. The method of solution 17, wherein the sample offset is indicated in a radio resource control (RRC) configuration, a medium access control (MAC) control element (CE) , or a downlink control information (DCI) field.

19. The method of solution 17, wherein the sample offset is set to a default value.

20. The method of any of solutions 6 to 10, wherein the wireless device is configured to use a code-division multiplexed (CDM) PTRS, and wherein at least one orthogonal cover code (OCC) is used across the two PTRS ports. At least this solution is detailed in Embodiments 4-5.

21. The method of solution 20, wherein a first set of OCCs of length 2 is used for different PTRS groups, and wherein a second set of OCCs is used within each of the different PTRS groups.

22. The method of solution 20, wherein a combined OCC is used for all samples for the two PTRS ports in one PTRS group.

23. The method of solution 22, wherein the combined OCC comprises an OCC of length 8 when 8 samples are supported in one PTRS group, and wherein the OCC of length 8 is at least one of:
[+1 +1 +1 +1 +1 +1 +1 +1] ,
[+1 -1 +1 -1 +1 -1 +1 -1] ,
[+1 +1 -1 -1 +1 +1 -1 -1] ,
[+1 -1 -1 +1 +1 -1 -1 +1] ,
[+1 +1 +1 +1 -1 -1 -1 -1] ,
[+1 -1 +1 -1 -1 +1 -1 +1] ,
[+1 -1 -1 +1 -1 -1 +1 +1] ,
[+1 -1 -1 +1 -1 +1 +1 -1] .

24. The method of any of solutions 6 to 10, wherein a first PTRS port is mapped to a first set of resources in a first layer, wherein a second PTRS port is mapped to a second set of resources in a second layer, wherein a corresponding first set of resources in the second layer and a corresponding second set of resources in the first layer are zero padded or padded with data. At least this solution is detailed in Embodiment 4.

25. An apparatus for wireless communication comprising a processor, configured to implement a method recited in one or more of solutions 1 to 24.

26. A non-transitory computer readable program storage medium having code stored thereon, the code, when executed by a processor, causing the processor to implement a method recited in one or more of solutions 1 to 24.

FIG. 5 shows an exemplary block diagram of a hardware platform 500 that may be a part of a network device (e.g., base station) or a communication device (e.g., a user equipment (UE) ) . The hardware platform 500 includes at least one processor 510 and a memory 505 having instructions stored thereupon. The instructions upon execution by the processor 510 configure the hardware platform 500 to perform the operations described in FIGS. 3 and 4 and in the various embodiments described in this patent document. The transmitter 515 transmits or sends information or data to another device. For example, a network device transmitter can send a message to a user equipment. The receiver 520 receives information or data transmitted or sent by another device. For example, a user equipment can receive a message from a network device.

The implementations as discussed above will apply to a wireless communication. FIG. 6 shows an example of a wireless communication system (e.g., a 5G or NR cellular network) that includes a base station 620 and one or more user equipment (UE) 611, 612 and 613. In some embodiments, the UEs access the BS (e.g., the network) using a communication link to the network (sometimes called uplink direction, as depicted by dashed arrows 631, 632, 633) , which then enables subsequent communication (e.g., shown in the direction from the network to the UEs, sometimes called downlink direction, shown by arrows 641, 642, 643) from the BS to the UEs. In some embodiments, the BS send information to the UEs (sometimes called downlink direction, as depicted by arrows 641, 642, 643) , which then enables subsequent communication (e.g., shown in the direction from the UEs to the BS, sometimes called uplink direction, shown by dashed arrows 631, 632, 633) from the UEs to the BS. The UE may be, for example, a smartphone, a tablet, a mobile computer, a machine to machine (M2M) device, an Internet of Things (IoT) device, and so on.

Some of the embodiments described herein are described in the general context of methods or processes, which may be implemented in one embodiment by a computer program product, embodied in a computer-readable medium, including computer-executable instructions, such as program code, executed by computers in networked environments. A computer-readable medium may include removable and non-removable storage devices including, but not limited to, Read Only Memory (ROM) , Random Access Memory (RAM) , compact discs (CDs) , digital versatile discs (DVD) , etc. Therefore, the computer-readable media can include a non-transitory storage media. Generally, program modules may include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Computer-or processor-executable instructions, associated data structures, and program modules represent examples of program code for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps or processes.

Some of the disclosed embodiments can be implemented as devices or modules using hardware circuits, software, or combinations thereof. For example, a hardware circuit implementation can include discrete analog and/or digital components that are, for example, integrated as part of a printed circuit board. Alternatively, or additionally, the disclosed components or modules can be implemented as an Application Specific Integrated Circuit (ASIC) and/or as a Field Programmable Gate Array (FPGA) device. Some implementations may additionally or alternatively include a digital signal processor (DSP) that is a specialized microprocessor with an architecture optimized for the operational needs of digital signal processing associated with the disclosed functionalities of this application. Similarly, the various components or sub-components within each module may be implemented in software, hardware or firmware. The connectivity between the modules and/or components within the modules may be provided using any one of the connectivity methods and media that is known in the art, including, but not limited to, communications over the Internet, wired, or wireless networks using the appropriate protocols.

While this document contains many specifics, these should not be construed as limitations on the scope of an invention that is claimed or of what may be claimed, but rather as descriptions of features specific to particular embodiments. Certain features that are described in this document in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a sub-combination or a variation of a sub-combination. Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results.

Only a few implementations and examples are described and other implementations, enhancements and variations can be made based on what is described and illustrated in this disclosure.

Claims

A wireless communication method, comprising:

receiving, by a wireless device from a network node, an indication for a single-carrier physical uplink shared channel (PUSCH) transmission comprising at least one phase tracking reference signal (PTRS) port and at least two demodulation reference signal (DMRS) ports; and

performing, based on the indication, the single-carrier PUSCH transmission.
A wireless communication method, comprising:

configuring, by a network node, a single-carrier physical uplink shared channel (PUSCH) transmission comprising at least one phase tracking reference signal (PTRS) port and at least two demodulation reference signal (DMRS) ports; and

transmitting, to a wireless device subsequent to the configuring, a wireless communication.
The method of claim 1 or 2, wherein the at least one PTRS port comprises one PTRS port.
The method of claim 3, wherein the one PTRS port is associated with a first DMRS port or a last DMRS port of the at least two DMRS ports.
The method of claim 3, wherein one bit in a downlink control information (DCI) field is used to indicate an association between the one PTRS port and up to two of the at least two DMRS ports.
The method of claim 1 or 2, wherein the at least one PTRS port comprises two PTRS ports.
The method of claim 6, wherein a first PTRS port of the two PTRS ports is associated with a first DMRS port of the at least two DMRS ports, and wherein a second PTRS port of the two PTRS ports is associated with a second DMRS port of the at least two DMRS ports.
The method of claim 6, wherein one bit in a downlink control information (DCI) field is used to indicate an association between the two PTRS ports and two DMRS ports of the at least two DMRS ports.
The method of claim 6, wherein two bits in a downlink control information (DCI) field are used to indicate an association between the two PTRS ports and more than two DMRS ports of the at least two DMRS ports.
The method of claim 6, wherein each of the two PTRS ports are mapped to a different orthogonal frequency division multiplexing (OFDM) symbol, a different PTRS group, or a different PTRS sample.
The method of claim 10, wherein a first PTRS port is mapped to a first OFDM symbol, and wherein a second PTRS port is mapped to a second OFDM symbol defined by a symbol offset from the first OFDM symbol.
The method of claim 11, wherein the symbol offset is indicated in a radio resource control (RRC) configuration, a medium access control (MAC) control element (CE) , a downlink control information (DCI) field.
The method of claim 11, wherein the symbol offset is set to a default value.
The method of claim 10, wherein a first PTRS port is mapped to a first PTRS group, and wherein a second PTRS port is mapped to a second PTRS group defined by a group offset from the first PTRS group.
The method of claim 14, wherein the group offset is indicated in a radio resource control (RRC) configuration, a medium access control (MAC) control element (CE) , or a downlink control information (DCI) field.
The method of claim 14, wherein the group offset is set to a default value.
The method of claim 10, wherein a first PTRS port is mapped to a first PTRS sample, and wherein a second PTRS port is mapped to a second PTRS sample defined by a sample offset from the first PTRS sample.
The method of claim 17, wherein the sample offset is indicated in a radio resource control (RRC) configuration, a medium access control (MAC) control element (CE) , or a downlink control information (DCI) field.
The method of claim 17, wherein the sample offset is set to a default value.
The method of claim 6, wherein the wireless device is configured to use a code-division multiplexed (CDM) PTRS, and wherein at least one orthogonal cover code (OCC) is used across the two PTRS ports.
The method of claim 20, wherein a first set of OCCs of length 2 is used for different PTRS groups, and wherein a second set of OCCs is used within each of the different PTRS groups.
The method of claim 20, wherein a combined OCC is used for all samples for the two PTRS ports in one PTRS group.
The method of claim 22, wherein the combined OCC comprises an OCC of length 8 when 8 samples are supported in one PTRS group, and wherein the OCC of length 8 is at least one of:
[+1 +1 +1 +1 +1 +1 +1 +1] ,
[+1 -1 +1 -1 +1 -1 +1 -1] ,
[+1 +1 -1 -1 +1 +1 -1 -1] ,
[+1 -1 -1 +1 +1 -1 -1 +1] ,
[+1 +1 +1 +1 -1 -1 -1 -1] ,
[+1 -1 +1 -1 -1 +1 -1 +1] ,
[+1 -1 -1 +1 -1 -1 +1 +1] ,
[+1 -1 -1 +1 -1 +1 +1 -1] .
The method of claim 6, wherein a first PTRS port is mapped to a first set of resources in a first layer, wherein a second PTRS port is mapped to a second set of resources in a second layer, wherein a corresponding first set of resources in the second layer and a corresponding second set of resources in the first layer are zero padded or padded with data.
An apparatus for wireless communication comprising a processor, configured to implement a method recited in one or more of claims 1 to 24.
A non-transitory computer readable program storage medium having code stored thereon, the code, when executed by a processor, causing the processor to implement a method recited in one or more of claims 1 to 24.