WO2020062005A1

WO2020062005A1 - A multiplexing mechanism of prs with different numerologies of gnbs and ue

Info

Publication number: WO2020062005A1
Application number: PCT/CN2018/108257
Authority: WO
Inventors: Zhe LUO; Tao Tao; Jianguo Liu; Yan Meng; Gang Shen
Original assignee: Nokia Shanghai Bell Co., Ltd.; Nokia Solutions And Networks Oy; Nokia Technologies Oy
Priority date: 2018-09-28
Filing date: 2018-09-28
Publication date: 2020-04-02
Also published as: CN112753255B; CN112753255A

Abstract

The objective of the disclosure of embodiments is to provide a multiplexing mechanism of PRS with different numerologies of gNBs and UE. location server obtains one or more multiplexing units for PRS of each one of the associated gNBs, and transmits PRS configurations of the associated gNBs to a corresponding UE, wherein the PRS configuration of a gNB includes the numerology information of the gNB and the indication of PRS resources of the gNB; each one of the associated gNBs transmits PRS to the corresponding UE on the allocated multiplexing unit (s) based on the dedicated RE mapping of the gNB corresponding to the numerology information of the gNB; the corresponding UE measures PRS based on the PRS configurations of the associated gNBs. The advantages of this disclosure of embodiments include the followings: the gNBs do not need to change their working numerologies frequently to support PRS transmission. It reduces the overhead of changing numerologies and increases the stability of frame type; the UE can measure PRS from the associated gNBs with different numerologies simultaneously. It reduces the latency of positioning; the location server can easily schedule gNBs to transmit PRS regardless of their preferred numerologies.

Description

A Multiplexing Mechanism of PRS with Different Numerologies of gNBs and UE

TECHNICAL FIELD

Various example embodiments relate generally to the technology of 5G communication, especially to a multiplexing mechanism of PRS with different numerologies.

BACKGROUND OF INVENTION

The study item of positioning has been discussed in 3GPP TSG RAN Meeting #80. One target of this is to support the NR-based positioning in 3GPP NR Rel-16, in both FR1 (below 6 GHz) and FR2 (above 6 GHz) for regulatory use cases such as ECID, OTDOA and UTDOA.

For OTDOA-based positioning, multiple eNBs or gNBs transmit PRS on some configured resources, and UE measures the PRS to estimate time difference of arrival from those eNBs or gNBs.

In legacy LTE, PRS transmitted from multiple eNBs can be multiplexing by FDM, i.e., allocating different REs, as shown in Fig. 1. FDM-based PRS has several advantages, including:

1. A UE can measure TOA of multiple eNBs at a measurement occasion, in order to reduce latency.

2. The eNB can boost transmission power of PRS by muting the other REs.

FDM-based PRS can be easily implemented for legacy LTE by using RE mapping, since all the eNBs use the same numerology (e.g., SCS 15 kHz) , i.e., the same RE grid.

Different from LTE, for NR, gNBs may use different numerologies, e.g., SCS 15/30/60 kHz for FR1 and SCS 120/240 kHz for FR2. In many cases, it is difficult to require all gNBs to transmit PRS with the same numerology, since their working numerologies may be various. Thus, it is beneficial to support FDM-based PRS with multiple numerologies for NR positioning. However, the existing multiplexing mechanism of RE mapping for LTE cannot apply to FDM-based PRS with multiple numerologies, since the RE grids for multiple numerologies are different. Therefore, a new multiplexing mechanism is required to support FDM-based PRS with multiple numerologies for NR positioning.

SUMMARY OF INVENTION

The objective of the disclosure of embodiments is to provide a multiplexing mechanism of PRS with different numerologies of gNBs and UE.

According to one aspect of the disclosure of embodiments, a method for multiplexing mechanism of PRS at a gNB, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the method comprises the following steps:

- determining one or more multiplexing units for PRS, wherein a multiplexing unit can be allocated to a gNB only when the bandwidth and the OS duration of a block of the multiplexing unit are multiples of SCS and OS duration of the gNB, respectively;

- transmitting PRS to the corresponding UE on the allocated multiplexing unit (s) based on the dedicated RE mapping of the gNB corresponding to the numerology information of the gNB.

According to another aspect of the disclosure of embodiments, a method for multiplexing mechanism of PRS at location server, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the method comprises the following steps:

- obtaining one or more multiplexing units for PRS of each one of the associated gNBs, wherein a multiplexing unit can be allocated to a gNB only when the bandwidth and the OS duration of a block of the multiplexing unit are multiples of SCS and OS duration of the gNB, respectively;

- transmitting PRS configurations of the associated gNBs to a corresponding UE, wherein the PRS configuration of a gNB includes the numerology information of the gNB and the indication of PRS resources of the gNB.

According to yet another aspect of the disclosure of embodiments, a method for multiplexing mechanism of PRS at a UE, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the method comprises the following steps:

- receiving PRS configurations of the associated gNBs from location server, wherein the PRS configuration of a gNB includes the numerology information of the gNB and the indication of PRS resources of the gNB;

- measuring PRS based on the PRS configurations of the associated gNBs.

According to another aspect of the disclosure of embodiments, a method for multiplexing mechanism of PRS, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the method comprises the following steps:

obtaining, by location server, one or more multiplexing units for PRS of each one of the associated gNBs, wherein a multiplexing unit can be allocated to a gNB only when the bandwidth and the OS duration of a block of the multiplexing unit are multiples of SCS and OS duration of the gNB, respectively;

transmitting, by the location server, PRS configurations of the associated gNBs to a corresponding UE, wherein the PRS configuration of a gNB includes the numerology information of the gNB and the indication of PRS resources of the gNB;

transmitting, by each one of the associated gNBs, PRS to the corresponding UE on the allocated multiplexing unit (s) based on the dedicated RE mapping of the gNB corresponding to the numerology information of the gNB;

measuring, by the corresponding UE, PRS based on the PRS configurations of the associated gNBs.

According to another aspect of the disclosure of embodiments, a gNB for multiplexing mechanism of PRS, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the gNB is configured to:

- determine one or more multiplexing units for PRS, wherein a multiplexing unit can be allocated to a gNB only when the bandwidth and the OS duration of a block of the multiplexing unit are multiples of SCS and OS duration of the gNB, respectively;

- transmit PRS to the corresponding UE on the allocated multiplexing unit (s) based on the dedicated RE mapping of the gNB corresponding to the numerology information of the gNB.

According to another aspect of the disclosure of embodiments, a location server for multiplexing mechanism of PRS at, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the location server is configured to:

- obtain one or more multiplexing units for PRS of each one of the associated gNBs, wherein a multiplexing unit can be allocated to a gNB only when the bandwidth and the OS duration of a block of the multiplexing unit are multiples of SCS and OS duration of the gNB, respectively;

- transmit PRS configurations of the associated gNBs to a corresponding UE, wherein the PRS configuration of a gNB includes the numerology information of the gNB and the indication of PRS resources of the gNB.

According to another aspect of the disclosure of embodiments, a UE for multiplexing mechanism of PRS, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the UE is configured to:

- receive PRS configurations of the associated gNBs from location server, wherein the PRS configuration of a gNB includes the numerology information of the gNB and the indication of PRS resources of the gNB;

- measure PRS based on the PRS configurations of the associated gNBs.

The advantages of this disclosure of embodiments include the followings:

1. The gNBs do not need to change their working numerologies frequently to support PRS transmission. It reduces the overhead of changing numerologies and increases the stability of frame type.

2. The UE can measure PRS from the associated gNBs with different numerologies simultaneously. It reduces the latency of positioning.

3. The location server can easily schedule gNBs to transmit PRS regardless of their preferred numerologies.

DESCRIPTION OF ACCOMPANIED DRAWINGS

Through reading the following detailed depiction on the non-limiting embodiments with reference to the accompanying drawings, the other features, objectives, and advantages of the disclosure of embodiments will become clearer.

Fig. 1 shows an exemplary schematic of Mapping of positioning reference signals (normal cyclic prefix) ;

Fig. 2 shows an exemplary flowchart of multiplexing mechanism of PRS with multiple numerologies according to an embodiment of this disclosure;

Fig. 3 shows an example of a common resource allocation pattern consisting of multiplexing units;

Figs. 4 (a) - (c) show the different dedicated RE mappings of various numerologies for multiplexing unit 0 in Fig. 3, respectively;

Fig. 5 shows an exemplary flowchart of the location server determining the common resource allocation pattern according to an embodiment of this disclosure;

Fig. 6 shows an example of a common resource allocation pattern with different block sizes;

Figs. 7 (a) - (d) show exemplary flowcharts of allocating multiplexing unit (s) to gNBs for PRS according to four embodiments of this disclosure, respectively;

Figs. 8 (a) - (c) show dedicated RE mappings for three gNBs based on common resource allocation pattern in Fig. 6, respectively.

Same or like reference numerals in the accompanying drawings indicate the same or corresponding components.

EMBODIMENT OF INVENTION

Herein, a list of abbreviations used in this disclosure of embodiments is presented as below:

CP Cyclic Prefix

ECID Enhanced Cell Identification

eNB Enhanced Node B

FDM Frequency Division Multiplexing

FR Frequency Range

gNB Next Generation Node B

ID Identification

LTE Long Term Evolution

NR New Radio

OFDM Orthogonal Frequency-Division Multiplexing

OS OFDM Symbol

OTDOA Observed Time Difference of Arrival

PRS Positioning Reference signal

RE Resource Element

SCS Subcarrier Spacing

TOA Time of Arrival

UE User Equipment

UTDOA Uplink Time Difference of Arrival

This disclosure of embodiments proposes a multiplexing mechanism of PRS with multiple numerologies. Using this multiplexing mechanism, gNBs do not need to change their numerologies for transmitting PRS. The basic idea of the multiplexing mechanism of PRS is to use a common resource allocation pattern to achieve FDM among multiple numerologies. The common resource allocation pattern consists of multiple non-overlapped multiplexing units of various block sizes. For different numerologies, a multiplexing unit can be interpreted as different dedicated RE mappings.

A multiplexing unit allocated to a gNB shall be compatible with the gNB’s working numerology. Otherwise, the corresponding dedicated RE mapping does not exist to the working numerology. For example, a multiplexing unit of block bandwidth 30 kHz cannot be allocated to a gNB with working numerology of SCS 60 kHz. For the same reason, a UE cannot measure PRS transmitted on an incompatible multiplexing unit. For example, a UE not supporting SCS 60 kHz cannot measure PRS of OS duration 512 Ts.

Hereinafter, this disclosure of embodiments will be further described in detail with reference to the accompanying drawings.

Fig. 2 illustrates a flowchart of an embodiment of the multiplexing mechanism of PRS with multiple numerologies.

In a PRS measurement scenario, a UE measures PRS from several gNBs, these gNBs are regarded as associated gNBs to the UE.

Referring to Fig. 2, in step S1, location server obtains one or more multiplexing units for PRS of each one of the associated gNBs; in step S2, the location server transmits PRS configurations of the associated gNBs to a corresponding UE; in step S3, each one of the associated gNBs transmits PRS to the corresponding UE on the allocated multiplexing unit (s) based on the dedicated RE mapping of the gNB corresponding to the gNB’s numerology information; in step S4, the corresponding UE measures PRS based on the PRS configurations of the associated gNBs.

Specifically, in step S1, the multiplexing unit (s) for PRS of an associated gNB is determined from a common resource allocation pattern for the associated gNBs consists of multiple non-overlapped multiplexing units.

The common resource allocation pattern may be determined by at least the following two ways:

1) The common resource allocation pattern can be pre-defined.

Referring to Fig. 3, it shows an example of a common resource allocation pattern consisting of multiplexing units, where all multiplexing units have the same size: bandwidth of 60 kHz and OS duration of 2048 Ts.

And Figs. 4 (a) - (c) show the different dedicated RE mappings of various numerologies, e.g., SCS 15/30/60 kHz respectively, for multiplexing unit 0 in Fig. 3. RE mappings for small and large SCS span multiple REs in frequency and time domains, respectively.

2) The location server determines the common resource allocation pattern and transmits it to the associated gNBs.

Referring to Fig. 5, in an embodiment, in step 501, the location server requests the numerology information (SCS) from the associated gNBs and the corresponding UE. For example, the location server requests working SCS from three gNBs and requests maximum supported SCS of a UE.

In step 502, the gNBs and UE respond to the location server with their numerology information. For example, these three gNBs respond to the location server with their working SCS 15 kHz, 30 kHz, 60 kHz, respectively, and the UE responds to the location server with its maximum supported SCS 60 kHz.

In step 503, the location server determines the common resource allocation pattern based on the received numerology information of the gNBs and UE. For example, the location server determines the common resource allocation pattern shown in Fig. 6, based on the received numerology information. The common resource allocation pattern consists of three multiplexing units of different block sizes.

In step 504, the location server transmits the common resource allocation pattern to its associated gNBs.

Then the multiplexing unit (s) for PRS of an associated gNB is chosen by the gNB or allocated by the location server as PRS resources.

A multiplexing unit can be allocated to a gNB only when the bandwidth and the OS duration of a block of the multiplexing unit are multiples of SCS and OS duration of the gNB, respectively.

The multiplexing unit (s) for PRS of gNBs can be allocated by at least the following four ways:

1) The allocated multiplexing unit (s) are calculated implicitly by the gNB.

With reference of Fig. 3 and Fig. 7 (a) , in an embodiment, the common resource allocation pattern is pre-defined as Fig. 3. In step 701a, the gNB implicitly calculates the multiplexing unit (s) for PRS based on the common resource allocation pattern. For example, the gNB of ID 15 calculates multiplexing unit 3 for PRS according to the equation: gNB-ID mod multiplexing-factor, where the multiplexing-factor is set to the number of multiplexing units and here is 4. In step 702a, the gNB transmits the location server the confirmation that it will send PRS on the implicitly calculated PRS resources.

2) The gNB chooses the multiplexing unit (s) by itself.

With reference of Fig. 3 and Fig. 7 (a) , in an embodiment, the common resource allocation pattern is pre-defined as Fig. 3. In step 701b, the gNB chooses multiplexing unit (s) for PRS from the common resource allocation pattern. For example, the gNB chooses multiplexing unit 0.In step 702b, the gNB transmits the location server the chosen multiplexing unit (s) . For example, the gNB transmits the chosen multiplexing unit 0 to the location server.

3) The gNB chooses the multiplexing unit (s) from the suggested multiplexing units given by the location server.

With reference of Fig. 6 and Fig. 7 (c) , in an embodiment, the common resource allocation pattern is determined by the location server as shown in Fig. 6. In step 701c, the location server sends the suggested multiplexing units for PRS to its associated gNBs. For example, the multiplexing

units

0 and 1 are suggested to be allocated to the gNB of ID 0 for PRS. In step 702c, the gNB chooses multiplexing unit (s) for PRS from the suggested ones. For example, the gNB of ID 0 chooses multiplexing unit 0 from the suggested

ones

0 and 1. In step 703c, the gNB responds to the location server with the chosen multiplexing unit (s) . For example, the gNB of ID 0 responds with the chosen multiplexing unit 0.

4) The location server explicitly configures the multiplexing unit (s) to the gNB.

With reference of Fig. 6 and Fig. 7 (d) , in an embodiment, the common resource allocation pattern is determined by the location server as shown in Fig. 6. In step 701d, the location server sends the allocated multiplexing unit (s) for PRS to its associated gNBs. For example, the location server sends the allocated multiplexing unit 1 for PRS to the gNB of ID 1. In step 702d, the gNB responds to the location server with the confirmation.

Referring back to Fig. 2, the following steps of S2-S4 are described according to an embodiment, where the common resource allocation pattern is determined by the location server as shown in Fig. 6, and the three multiplexing

units

1, 2, 3 are allocated to three gNBs of

ID

0, 1, 2 with SCS 15 kHz, 30 kHz, 60 kHz, respectively.

In step S2, location server transmits PRS configurations of the associated gNBs to a corresponding UE.

The PRS configuration of an associated gNB includes the numerology information of the gNB, i.e. working SCS, and the indication of PRS resources of the gNB.

The indication of PRS resources of the gNB may include one of the following items:

1) the multiplexing unit (s) for PRS of the gNB;

For example, the PRS configuration for the gNB of ID 0 includes: the common resource allocation pattern, and the index 0 of the allocated multiplexing unit. For another example, the PRS configuration for the gNB of ID 1 includes: the position and the size of the allocated multiplexing unit 1.

2) the dedicated RE mapping of the gNB.

For example, the PRS configuration for the gNB of ID 2 includes the dedicated RE mapping shown in Fig. 8 (c) .

In step S3, each one of the associated gNBs transmits PRS to the corresponding UE on the allocated multiplexing unit (s) based on the dedicated RE mapping of the gNB corresponding to the gNB’s numerology information.

The gNB transmits PRS based on the dedicated RE mapping corresponding to the PRS configuration. For example, the dedicated RE mapping of the gNB of ID 0 shown in Fig. 8 (a) is calculated based on the common resource allocation pattern, the index 0 of the allocated multiplexing unit and the numerology, where the number of REs in the same OS, i.e., 2, is equal to the bandwidth of a block of multiplexing unit 0 (30 kHz) divided by the SCS (15 kHz) , and the number of REs in the same subcarrier, i.e., 1, is equal to the duration of a block of multiplexing unit 0 (2048 Ts) divided by the OS length (2048 Ts) . For another example, the dedicated RE mapping of the gNB of ID 1 shown in Fig. 8 (b) is calculated based on the allocated multiplexing unit 1 and the numerology, where the number of REs (1) in the same OS is equal to the bandwidth of a block of multiplexing unit 1 (30 kHz) divided by the SCS (30 kHz) , and the number of REs (2) in the same subcarrier is equal to the duration of a block of multiplexing unit 1 (2048 Ts) divided by the OS length (1024 Ts) . For yet another example, , the dedicated RE mapping of the gNB of ID 2 shown in Fig. 8 (c) is given directly, where the number of REs (1) in the same OS is equal to the bandwidth of a block of multiplexing unit 2 (60 kHz) divided by the SCS (60 kHz) , and the number of REs (4) in the same subcarrier is equal to the duration of a block of multiplexing unit 2 (2048 Ts) divided by the OS length (512 Ts) .

In step S4, the corresponding UE measures PRS based on the PRS configurations of the associated gNBs.

The UE obtains the PRS configurations of the associated gNBs in step S2. Then, in step S4, the UE measures PRS based on the calculated and/or given dedicated RE mappings of gNBs. In an embodiment, the UE first buffers 2048 sampling points (without considering CP) of the maximum OS duration (2048 Ts) . In an embodiment, the UE gets PRS of the gNB 0 by demodulating OS of SCS 15 kHz, i.e., doing FFT of size 2048 for the 2048 sampling points. In another embodiment, the UE gets PRS of the gNB 1 by demodulating OS of SCS 30 kHz, i.e., doing FFT of size 1024 twice for the 2048 sampling points. In another embodiment, the UE gets PRS of the gNB 2 by demodulating OS of SCS 60 kHz, i.e., doing FFT of size 512 four times for the 2048 sampling points.

It should be noted that the disclosure of embodiments may be implemented in software or a combination of software and hardware; for example, it may be implemented by an ASIC (Application Specific Integrated Circuit) , a general-purpose computer, or any other similar hardware devices.

The software program of the disclosure of embodiments may be executed by a processor to implement the above steps or functions. Likewise, the software program of the disclosure of embodiments (including relevant data structure) may be stored in a computer readable recording medium, for example, a RAM memory, a magnetic or optical driver, or a floppy disk, and other similar devices. Besides, some steps or functions of the disclosure of embodiments may be implemented by hardware, for example, a circuit cooperating with a processor to execute various functions or steps.

Additionally, a portion of the disclosure of embodiments may be applied as a computer program product, for example, a computer program instruction, which, may invoke or provide a method and/or technical solution according to the disclosure of embodiments through operations of the computer when executed by the computer. Further, the program instruction invoking the method of the disclosure of embodiments may be stored in a fixed or mobile recording medium, and/or transmitted through broadcast or data flow in other signal bearer media, and/or stored in a working memory of a computer device which operates based on the program instruction. Here, one embodiment according to the disclosure of embodiments comprises an apparatus comprising a memory for storing a computer program instruction and a processor for executing the program instruction, wherein when the computer program instruction is executed by the processor, the apparatus is triggered to run the methods and/or technical solutions according to a plurality of embodiments of the disclosure of embodiments.

To those skilled in the art, it is apparent that the disclosure of embodiments is not limited to the details of the above exemplary embodiments, and the disclosure of embodiments may be implemented with other embodiments without departing from the spirit or basic features of the disclosure of embodiments. Thus, in any way, the embodiments should be regarded as exemplary, not limitative; the scope of the disclosure of embodiments is limited by the appended claims instead of the above description, and all variations intended to fall into the meaning and scope of equivalent elements of the claims should be covered within the disclosure of embodiments. No reference signs in the claims should be regarded as limiting of the involved claims. Besides, it is apparent that the term “comprise” does not exclude other units or steps, and singularity does not exclude plurality. A plurality of units or modules stated in a system claim may also be implemented by a single unit or module through software or hardware. Terms such as the first and the second are used to indicate names, but do not indicate any particular sequence.

Claims

A method for multiplexing mechanism of PRS at a gNB, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the method comprises the following steps:

-determining one or more multiplexing units for PRS, wherein a multiplexing unit can be allocated to a gNB only when the bandwidth and the OS duration of a block of the multiplexing unit are multiples of SCS and OS duration of the gNB, respectively;

-transmitting PRS to the corresponding UE on the allocated multiplexing unit (s) based on the dedicated RE mapping of the gNB corresponding to the numerology information of the gNB.
The method of claim 1, wherein the common resource allocation pattern is determined by location server based on the numerology information of the associated gNBs and of the corresponding UE.
The method of claim 1 or 2, wherein the one or more multiplexing units for PRS is determined by the gNB.
The method of claim 3, wherein the one or more multiplexing units for PRS is chosen from the multiplexing units suggested by location server.
The method of claim 1 or 2, wherein the one or more multiplexing units for PRS is configured by location server.
A method for multiplexing mechanism of PRS at location server, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the method comprises the following steps:

-obtaining one or more multiplexing units for PRS of each one of the associated gNBs, wherein a multiplexing unit can be allocated to a gNB only when the bandwidth and the OS duration of a block of the multiplexing unit are multiples of SCS and OS duration of the gNB, respectively;

-transmitting PRS configurations of the associated gNBs to a corresponding UE, wherein the PRS configuration of a gNB includes the numerology information of the gNB and the indication of PRS resources of the gNB.
The method of claim 6, wherein the method further comprises the following steps:

-obtaining the numerology information of the associated gNBs and the corresponding UE, respectively;

-determining the common resource allocation pattern based on the obtained numerology information;

-configuring the common resource allocation pattern to the associated gNBs.
The method of claim 6 or 7, wherein the indication of PRS resources of the gNB includes one of the followings:

-the multiplexing unit (s) for PRS of the gNB;

-the dedicated RE mapping of the gNB.
A method for multiplexing mechanism of PRS at a UE, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the method comprises the following steps:

-receiving PRS configurations of the associated gNBs from location server, wherein the PRS configuration of a gNB includes the numerology information of the gNB and the indication of PRS resources of the gNB;

-measuring PRS based on the PRS configurations of the associated gNBs.
A method for multiplexing mechanism of PRS, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the method comprises the following steps:

obtaining, by location server, one or more multiplexing units for PRS of each one of the associated gNBs, wherein a multiplexing unit can be allocated to a gNB only when the bandwidth and the OS duration of a block of the multiplexing unit are multiples of SCS and OS duration of the gNB, respectively;

transmitting, by the location server, PRS configurations of the associated gNBs to a corresponding UE, wherein the PRS configuration of a gNB includes the numerology information of the gNB and the indication of PRS resources of the gNB;

transmitting, by each one of the associated gNBs, PRS to the corresponding UE on the allocated multiplexing unit (s) based on the dedicated RE mapping of the gNB corresponding to the numerology information of the gNB;

measuring, by the corresponding UE, PRS based on the PRS configurations of the associated gNBs.
The method of claim 10 wherein the method further comprises the following steps performed by the location server:

-obtaining the numerology information of the associated gNBs and the corresponding UE, respectively;

-determining the common resource allocation pattern based on the obtained numerology information;

-configuring the common resource allocation pattern to the associated gNBs.
The method of claim 10 or 11, wherein the indication of PRS resources of the gNB includes one of the followings:

-the multiplexing unit (s) for PRS of the gNB;

-the dedicated RE mapping of the gNB.
A gNB for multiplexing mechanism of PRS, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the gNB is configured to:

-determine one or more multiplexing units for PRS, wherein a multiplexing unit can be allocated to a gNB only when the bandwidth and the OS duration of a block of the multiplexing unit are multiples of SCS and OS duration of the gNB, respectively;

-transmit PRS to the corresponding UE on the allocated multiplexing unit (s) based on the dedicated RE mapping of the gNB corresponding to the numerology information of the gNB.
A location server for multiplexing mechanism of PRS at, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the location server is configured to:

-obtain one or more multiplexing units for PRS of each one of the associated gNBs, wherein a multiplexing unit can be allocated to a gNB only when the bandwidth and the OS duration of a block of the multiplexing unit are multiples of SCS and OS duration of the gNB, respectively;

-transmit PRS configurations of the associated gNBs to a corresponding UE, wherein the PRS configuration of a gNB includes the numerology information of the gNB and the indication of PRS resources of the gNB.
A UE for multiplexing mechanism of PRS, wherein a common resource allocation pattern for associated gNBs consists of multiple non-overlapped multiplexing units for PRS;

wherein the UE is configured to:

-receive PRS configurations of the associated gNBs from location server, wherein the PRS configuration of a gNB includes the numerology information of the gNB and the indication of PRS resources of the gNB;

-measure PRS based on the PRS configurations of the associated gNBs.