Method, UE, and integrated circuit for RSTD measurement report mapping

Abstract

Methods, a UE, and an integrated circuit for RSTD measurement report mapping are disclosed. A user equipment (UE) is configured to establish a connection with a network that includes a first cell and a second cell. The UE receives a positioning reference signal from each of the first cell and the second cell, determines a frequency band of each of the positioning reference signals, determines a reference signal time difference (RSTD) value from a measurement time offset between the positioning reference signals from the first cell and the second cell, determines an RSTD report value based at least on the RSTD value and the determined frequency band, and transmits an indication of the RSTD report value to the network.

Description

Background Art

[0001] Observed Time Difference of Arrival (OTDOA) is a multi-point positioning technique in which a User Equipment (UE) receives positioning reference signals (PRS) from each of a plurality of network cells. The UE determines the precise offsets between the arrival times of the PRS to generate a set of Reference Signal Time Difference (RSTD) values to report to the network. The granularity at which the reporting is done can affect OTDOA performance. For example, a finer granularity can improve the accuracy of the measurements, but increases the amount of reporting as well as the network overhead required to report the measurements, while a coarser granularity may be less accurate, but reduces the amount of reporting as well as the network overhead required to report the measurements. Summary of the Invention

[0002] According to some exemplary embodiments, a method may be performed by a User Equipment (UE) configured to establish a connection with a network that includes a first cell and a second cell. The method includes receiving positioning reference signals from each of the first cell and the second cell, determining the frequency band of each of the positioning reference signals, determining a Reference Signal Time Difference (RSTD) value from the measured time offset between the positioning reference signals from the first cell and the second cell, determining an RSTD reporting value based at least on the RSTD value and the determined frequency band, and transmitting an indication of the RSTD reporting value to the network.

[0003] According to other exemplary embodiments, a User Equipment (UE) is provided. The UE includes a transceiver configured to establish a connection with a network that includes a first cell and a second cell, the transceiver receiving positioning reference signals from each of the first cell and the second cell. The UE further includes a processor configured to determine the frequency band of each of the positioning reference signals, determine a Reference Signal Time Difference (RSTD) value from the measured time offset between the positioning reference signals from the first cell and the second cell, and determine an RSTD reporting value based at least on the RSTD value and the determined frequency band. The transceiver transmits an indication of the RSTD reporting value to the network.

[0004] According to additional exemplary embodiments, an integrated circuit is provided. The integrated circuit includes: circuitry configured to establish a connection with a network that includes a first cell and a second cell; circuitry configured to receive positioning reference signals from each of the first cell and the second cell; circuitry configured to determine the frequency band of each of the positioning reference signals; circuitry configured to determine a Reference Signal Time Difference (RSTD) value from the measured time offset between the positioning reference signals from the two cells; circuitry configured to determine an RSTD reporting value based at least on the RSTD value and the determined frequency band; and circuitry for transmitting an indication of the RSTD reporting value to the network. Brief Description of the Drawings

[0005] Figure 1 shows a network arrangement according to various exemplary embodiments.

[0006] Figure 2 shows an exemplary UE according to various exemplary embodiments.

[0007] Figure 3 shows an exemplary system arrangement according to various exemplary embodiments, which includes a UE configured for OTDOA function, Figure 1 the UE having a network connection with a network cell and being able to receive positioning signals from a plurality of additional network cells.

[0008] Figure 4 shows a method for RSTD measurement report mapping for UE positioning in 5G NR implemented at a UE according to various exemplary embodiments. DETAILED DESCRIPTION

[0009] The exemplary embodiments may be further understood with reference to the following description and the associated drawings, in which like elements are assigned the same reference numerals. The exemplary embodiments describe devices, systems, and methods for reporting reference signal time difference (RSTD) values to a network for observed time difference of arrival (OTDOA) positioning. Specifically, the exemplary embodiments provide an RSTD measurement report mapping framework for variable measurement granularity in a 5G new radio (NR) network based on various network connection considerations described in detail below.

[0010] Figure 1 shows a network arrangement 100 according to various exemplary embodiments. The network arrangement 100 includes a UE 110. Those skilled in the art will understand that the UE 110 may be any type of electronic component configured to communicate via a network, such as, for example, a mobile phone, a tablet computer, a smart phone, a phablet, an embedded device, a wearable device, a Cat-M device, a Cat-M1 device, an MTC device, an eMTC device, other types of Internet of Things (IoT) devices, etc. An actual network arrangement may include any number of UEs used by any number of users. Thus, the example of a single UE 110 is provided only for illustrative purposes.

[0011] The UE 110 can be configured to communicate with one or more networks. As previously described, exemplary embodiments will be described with respect to a UE capable of connecting to a 5G New Radio (NR) Radio Access Network (5G NR-RAN) 120. However, those skilled in the art will understand that the exemplary embodiments can also be applied to other RANs. In the example of network configuration 100, the networks with which the UE 110 can communicate wirelessly are the 5G NR-RAN 120, a legacy RAN 122, and a Wireless Local Area Network (WLAN) 124. Thus, the UE 110 can include a 5G NR chipset for communicating with the 5G RAN 120, a legacy chipset for communicating with the legacy RAN 122, and an ISM chipset for communicating with the WLAN 124. However, the UE 110 can also communicate with other types of wireless networks, and the UE 110 can also communicate with the network via a wired connection.

[0012] The 5G-RAN 120 and the legacy RAN 122 can be part of a cellular network that can be deployed by a cellular service provider (e.g., Verizon, AT&T, Sprint, T-Mobile, etc.). These networks 120, 122 can include, for example, cells or base stations (NodeB, eNodeB, HeNB, eNBS, gNB, gNodeB, macro cell base stations, micro cell base stations, small cell base stations, femto cell base stations, etc.) configured to send and receive traffic from UEs equipped with appropriate cellular chipsets. The WLAN 124 can include any type of wireless local area network (WiFi, hotspots, IEEE 802.11x networks, etc.).

[0013] The UE 110 can be connected to the 5G-RAN 120 via a Next Generation Node B (gNB) 120A. Those skilled in the art will understand that any relevant process can be performed for the UE 110 to connect to the 5G NR-RAN 120. For example, as discussed above, the 5G NR-RAN 120 can be associated with a particular cellular service provider at which the UE 110 and / or its user has contract and credential information (e.g., stored on the SIM). Upon detecting the presence of the 5G NR-RAN 120, the UE 110 can transmit the corresponding credential information in order to associate with the 5G NR-RAN 120. More specifically, the UE 110 can be associated with a particular cell (e.g., the gNB 120A of the 5G NR-RAN 120). As mentioned above, the use of the 5G NR-RAN 120 is for illustrative purposes, and according to the exemplary embodiments described herein, other types of networks can be used. For example, the UE 110 can also be connected to the legacy RAN 122.

[0014] In addition to networks 120, 122, and 124, network arrangement 100 further includes a cellular core network 130, the Internet 140, an IP Multimedia Subsystem (IMS) 150, and a network service backbone 160. The cellular core network 130 can be regarded as an interconnected collection of components that manage the operation and traffic of the cellular network. The cellular core network 130 also manages the traffic flowing between the cellular network and the Internet 140. The IMS 150 can generally be described as an architecture for delivering multimedia services to UEs 110, 112 using IP protocols. The IMS 150 can communicate with the cellular core network 130 and the Internet 140 to provide multimedia services to the UE 110. The network service backbone 160 communicates directly or indirectly with the Internet 140 and the cellular core network 130. The network service backbone 160 can generally be described as a set of components (e.g., servers, network storage arrangements, etc.) that implement a set of services that can be used to extend the functions for the UE 110 to communicate with various networks.

[0015] Figure 2 An exemplary UE 110 is shown in accordance with various exemplary embodiments. The UE 110 will be described with reference to Figure 1 the network arrangement 100. The UE 110 can represent any electronic device and can include a processor 205, a memory arrangement 210, a display device 215, an input / output (I / O) device 220, a transceiver 225, and other components 230. The other components 230 can include, for example, a first SIM (SIM 1), a second SIM (SIM 2), an audio input device, an audio output device, a battery providing a limited power source, a data acquisition device, a port for electrically connecting the UE 110 to other electronic devices, a sensor for detecting the condition of the UE 110, etc.

[0016] The processor 205 can be configured to execute multiple engines of the UE 110. For example, the engines can include an RSTD measurement reporting engine 245. The RSTD measurement reporting 245 can process the PRS received from each of the multiple gNBs and generate a report of the measured RSTD values for transmission to the network. The manner of reporting these RSTD values and the associated granularity will be described in more detail below.

[0017] The above engines, as applications (e.g., programs) executed by the processor 205, are merely exemplary. The functions associated with the engines may also be represented as separate integrated components of the UE 110, or may be modular components coupled to the UE 110, e.g., integrated circuits with or without firmware. For example, an integrated circuit may include an input circuit for receiving signals and a processing circuit for processing signals and other information. The engines may also be embodied as one application or multiple separate applications. Additionally, in some UEs, the functions described for the processor 205 are split between two or more processors such as a baseband processor and an application processor. The exemplary embodiments may be implemented in any of these or other configurations of the UE.

[0018] The memory 210 may be a hardware component configured to store data related to operations performed by the UE 110. As will be described in further detail below, the memory 210 may store data associated with the RSTD value reporting framework of the UE 110. The display device 215 may be a hardware component configured to display data to the user, while the I / O device 220 may be a hardware component that enables the user to make inputs. The display device 215 and the I / O device 220 may be separate components or may be integrated together (such as at a touch screen). The transceiver 225 may be a hardware component configured to establish connections with the 5G NR-RAN 120, legacy RAN 122, WLAN 124, etc. Thus, the transceiver 225 may operate on multiple different frequencies or channels (e.g., a set of contiguous frequencies).

[0019] Figure 3 An exemplary system arrangement 300 according to various exemplary embodiments is shown, which includes a UE 110 configured for OTDOA functionality, the UE having a network connection with a network cell and being able to receive positioning signals from a plurality of additional network cells. It will be described with respect to Figure 1 the network arrangement 100 of Figure 2 and the UE 110 of Figure 3 .

[0020] The exemplary system arrangement 300 shows a UE 110 configured with a network connection to a 5G NR radio access network (RAN) 120 (i.e., a network connection via gNB 120A). The UE 110 may also be able to operate to receive signals from gNB 120B and gNB 120C without establishing a dedicated connection. However, the UE 110 may establish additional network connections and / or receive signals from additional network cells. OTDOA measurements use signaling from at least three cells, but since each individual measurement has an uncertainty level associated with it, more cells may be used to improve the accuracy of the measurement.

[0021] OTDOA is a downlink (DL) positioning procedure in which a user equipment (UE) receives positioning reference signals (PRS) from at least three network cells and determines the time of arrival (TOA) for each PRS. A first cell is selected as a reference cell, and the time difference between the TOA of the first cell and each of the TOAs of the remaining cells is calculated. The relative time difference between two of these cells is a reference signal time difference (RSTD) measurement. Thus, in an arrangement including gNBs 120A, 120B, and 120C Figure 3 , gNB 120A can be selected as the reference cell, and the relative time difference between the TOA of gNB 120A and 120B and the relative time difference between the TOA of gNB 120A and gNB 120C can be RSTD measurements for the OTDOA procedure. The reporting granularity for UE / gNB timing measurements in 5G NR is defined by Formula 1: T = T c 2 k , where k is a configuration parameter with a minimum value of 0, and Tc is the baseline time granularity unit. In other words, the finest reporting granularity is T c (where k = 0), while other reporting granularities can be used, such as 2T c (where k = 1), 4T c (where k = 2), 8T c (where k = 3), and so on. The baseline granularity unit for UE / eNB timing measurements in the Long-Term Evolution (LTE) network is T s , where T s = 64T c . The basic RSTD reporting granularity of LTE is 1.0T s , with a higher resolution of 0.5T s . The reporting granularity of 5G NR can be much finer than that of LTE. T s has a value of 1 / (15000 * 2048), as determined by the granularity formula (Formula 2) provided below, using an SCS value of 15 kHz and an FFT size of 2048, which is equal to approximately 32 ns. T s is related to approximately 9.8 meters, that is, the distance traveled by a radio signal in T s seconds. Thus, T c is equal to approximately 0.5 ns and is related to approximately 15 cm.

[0022] In LTE, the following RSTD reporting mapping table specified in Table 9.1.10.3-1 of TS36.133 (labeled as Table 1 in this document) can be used to report RSTD values to the network, where the measured RSTD quantity value is related to the RSTD reporting value in the range from RSTD_0000 to RSTD_12711. This LTE RSTD reporting mapping table can be used for RSTD reporting in 5G NR. However, the exemplary embodiments may also include supplementary tables, such as a relative quantity value table. These tables will be described in further detail below.

[0023] Table 9.1.10.3-1: RSTD Report Mapping

[0024] Report Value Measured Quantity Value Unit RSTD_0000 -15391 > RSTD <![CDATA[T S > RSTD_0001 -15391 ≤ RSTD < -15386 <![CDATA[T S > … … … RSTD_2258 -4106 ≤ RSTD < -4101 <![CDATA[T S > RSTD_2259 -4101 ≤ RSTD < -4096 <![CDATA[T S > RSTD_2260 -4096 ≤ RSTD < -4095 <![CDATA[T S > RSTD_2261 -4095 ≤ RSTD < -4094 <![CDATA[T S > … … … RSTD_6353 -3 ≤ RSTD < -2 <![CDATA[T S > RSTD_6354 -2 ≤ RSTD < -1 <![CDATA[T S > RSTD_6355 -1 ≤ RSTD < 0 <![CDATA[T S > RSTD_6356 0 < RSTD ≤ 1 <![CDATA[T S > RSTD_6357 1 < RSTD ≤ 2 <![CDATA[T S > RSTD_6358 2 < RSTD ≤ 3 <![CDATA[T S > … … … RSTD_10450 4094 < RSTD ≤ 4094 <![CDATA[T S > RSTD_10451 4095 < RSTD ≤ 4096 <![CDATA[T S > RSTD_10452 4096 < RSTD ≤ 4101 <![CDATA[T S > RSTD_10453 4101 < RSTD ≤ 4106 <![CDATA[T S > … … … RSTD_12709 15381 < RSTD ≤ 15386 <![CDATA[T S > RSTD_12710 15386 < RSTD ≤ 15391 <![CDATA[T S > RSTD_12711 15391<RSTD <![CDATA[T S >

[0025] Table 1 (LTE)

[0026] The reported RSTD values in Table 1, and similarly for the corresponding 5G NR RSTD reporting mapping table to be described below, can be subdivided into ranges that share common reporting characteristics, which will be further explained below. The first range from RSTD_0001 to RSTD_2259 can be referred to as "Range 1", the second range from RSTD_2260 to RSTD_10451 can be referred to as "Range 2", and the third range from RSTD_10451 to RSTD_12710 can be referred to as "Range 3". In other embodiments, the ranges can be defined differently. The reported relative quantity values in the 5G NR RSTD relative quantity value reporting mapping table to be described below can depend on radio link factors, such as radio link conditions, signal-to-noise ratio (SNR), line of sight between the UE and the network cell, etc. For example, a coarser granularity can be used for poor radio links, and a finer granularity can be used for good radio links.

[0027] In 5G NR, the time fragmentation granularity used by the UE is determined by the subcarrier spacing (SCS) of the received PRS and the fast Fourier transform (FFT) size used to decompose the received signal, as shown in Equation 2: where Δf represents the SCS size, and N f represents the FFT size. The FFT size used by the UE is the smallest FFT size available for decomposing a given number of resource blocks (RBs) without oversampling. As is known to those skilled in the art, the FFT size can be, for example, 512, 1024, 2048, 4096, etc. Thus, to give an example, if the maximum transmission bandwidth configuration number (N rb) If it is 160, the total SCS size quantity is 160 * 12 = 1920 (i.e., each RB has 12 subcarriers), and the minimum FFT size without oversampling will be 2048. Given the SCS value and bandwidth (BW) value, N rb can be determined based on Tables 2 and 3 as follows.

[0028] Maximum transmission bandwidth configuration N RB

[0029]

[0030] Table 2

[0031] Maximum transmission bandwidth configuration N RB

[0032]

[0033] Table 3

[0034] Therefore, from the foregoing, the maximum transmission bandwidth configuration N of the PRS can be determined from the PRS SCS (Δf) and BW rb , and the minimum FFT size is determined from N rb .

[0035] The maximum channel bandwidth (CBW) for a given SCS on a given frequency band (FR1 or FR2) can also be determined from Tables 2 - 3, such as the maximum PRS measurement BW (PRB). The table values are reduced to an increment of 12 as shown in Table 4 below, which summarizes the PRB ranges for a given SCS on a given frequency band. It should be noted that certain SCS and CBW combinations from Tables 2 - 3 (specifically, combination 1) SCS = 30 kHz and CBW = 5 MHz, 2) SCS = 60 kHz and CBW = 10 MHz, and 3) SCS = 60 kHz and CBW = 15 MHz) are excluded from this maximum CBW determination. These combinations are excluded because they represent RSTD measurements that are less likely to occur in operation. However, based on the information provided herein, those skilled in the art will understand the manner of determining and using the CBW for these combinations.

[0036]

[0037] Table 4

[0038] As shown above, within the PRB range, the FFT size and time fragmentation granularity can be derived. This is summarized in Table 5 below. It should be noted that the granularity of 5G NR is specified as not exceeding 1.0T s (64T c ), so when a coarser granularity than 64T c is determined from the above calculations, 64T is usedc The baseline granularity.

[0039]

[0040]

[0041] Table 5

[0042] From the table provided above, the granularity is shown with respect to the frequency (FR1 or FR2), SCS, and PRB. Using this table as a baseline, multiple options for RSTD report mapping are detailed below. In an exemplary embodiment, three different types of RSTD mapping tables are provided. In a first exemplary embodiment, the RSTD mapping table is based on frequency and SCS. In a second exemplary embodiment, the RSTD mapping table is based on frequency. In a third exemplary embodiment, the RSTD mapping table is based on frequency, SCS, and BW. Each of these exemplary embodiments will be described in more detail below. However, the principles described below for generating an exemplary RSTD mapping table can be used to generate an RSTD mapping table based on different parameters or different combinations of parameters. Those skilled in the art will understand that the radio spectrum currently allocated to 5G includes Frequency Range 1 (FR1) (e.g., 410 megahertz (MHz) to 7125 MHz) and Frequency Range 2 (FR2) (e.g., 24250 MHz to 52600 MHz). Therefore, when FR1 and FR2 are mentioned in this specification, it should be understood that these are references to the current frequency ranges allocated to 5G. However, those skilled in the art will understand that the principles described herein can be extended to other frequency ranges.

[0043] According to a first exemplary embodiment, the RSTD mapping table is defined by SCS and by frequency band. The maximum / minimum values of the RSTD mapping table are the same in 5G NR as in LTE, i.e., the range of reported values is from RSTD_0000 to RSTD_12711. A relative quantity mapping table is also used to meet the positioning coverage requirements. The RSTD report mapping table is designed based on the baseline granularity described below, where the relative quantity mapping table is based on a finer granularity.

[0044] As shown in the exemplary Table 6 below, the mapping table includes five entries for five combinations of frequency and SCS: FR1 and SCS = 15 kHz, FR1 and SCS = 30 kHz, FR1 and SCS = 60 kHz, FR2 and SCS = 60 kHz, and FR2 and SCS = 120 kHz. In an exemplary embodiment, the time fragmentation granularity for each entry can be selected as the finest granularity between different BWs within each SCS (as can be seen with respect to Table 5). In other exemplary embodiments, different granularities (e.g., the coarsest granularity, the mean, or the average granularity, etc.) can be selected.

[0045] Basic Time Fragment Granularity without Oversampling for Different SCS

[0046]

[0047] Table 6

[0048] For the RSTD range from RSTD_2260 to RSTD_10451 (i.e., Range 2 as defined above), the oversampling rate reported by RSTD can be set to 2, which is further explained below. Thus, in the exemplary Table 7 shown below, the mapping table for Range 2 has twice the granularity of the resolution of Ranges 1 and 3.

[0049] Time Fragment Granularity with Oversampling Rate = 2 for Different SCS

[0050]

[0051] Table 7

[0052] When performing RSTD measurements between PRSs with different SCSs, the UE may follow the worst granularity between the two SCSs for reporting. The same applies when the PRSs have different FRs or BWs. As described above, in 5G NR, both the RSTD report mapping table and the relative quantity mapping table will be used. The same baseline unit as in LTE can be used in 5G NR. Thus, if the unit in LTE is 1.0 Ts, the unit in 5G NR can be 64 Tc. In 5G NR, the relative quantity mapping table provides more values to cover different SCSs in the FR1 RSTD report mapping. Comparing the finest SCS of FR1 and the finest SCS of FR2, there is a 4x difference between the reporting granularities for FR1 and FR2, so 16 Tc can be used as the unit in the case of FR2, such that the same signaling can be used for both the FR1 and FR2 cases, and only the interpretation of the signaling at the network is defined. For FR2, due to the network coverage of FR2, the positioning coverage may be less than that of FR1. In an exemplary implementation, 1 / 4 of the unit from FR1 is used for FR2 (meaning the unit for FR2 can be 16 Tc), the boundary of the RSTD report range can be 16 Tc * 15391 = 246256 Tc, and it can cover positioning measurements for distance differences up to 37.6 km.

[0053] Therefore, for the RSTD report mapping table, the granularity unit for FR1 is 64 Tc, and the granularity unit for FR2 is 16 Tc. For all SCSs in FR1 and FR2, the relative quantity mapping table may have the same signaling granularity, but the applicability of each signaling value shall be defined by FR and by SCS. For example, in FR1, the 15 kHz SCS has an oversampling granularity of 16 Tc for the range 2 and the base granularity of 32 Tc, while the 30 kHz / 60 kHz SCS has an oversampling granularity of 8 Tc for the range 2. To design the relative quantity mapping table, if the relative quantity is divisible by 8 Tc but not by 16 Tc, it means that it will be applied to the 30 kHz / 60 kHz SCS without oversampling in the range 2. If the relative quantity is divisible by 16 Tc, it means that it can be applied to the 15 kHz SCS with oversampling in the range 2 and can also be applied to the 30 kHz / 60 kHz SCS with the entire RSTD report range.

[0054] The RSTD report mapping table for FR1 for the first embodiment is shown in Table 8 below, while the relative quantity mapping table for FR1 is shown in Table 9 below.

[0055] RSTD Report Mapping for FR1

[0056]

[0057]

[0058] Table 8 Relative Quantity Mapping of Different SCS in FR1

[0059]

[0060]

[0061]

[0062] Table 9

[0063] For FR1, the UE shall report the reference quantity based on Table 8 and the relative quantity defined in Table 9 such that the difference between the measured RSTD quantity and the lower limit of the corresponding range from Table 9 is between Δ RSTD and Δ RSTD + resolutionStep. The resolutionStep is 16 Tc for the 15 kHz SCS in the range 2, 8 Tc for the 30 kHz SCS, and 8 Tc for the 60 kHz, and is 32 Tc for the 15 kHz SCS, 16 Tc for the 30 kHz SCS, and 16 Tc for the 60 kHz SCS in the ranges 1 and 3.

[0064] The RSTD report mapping table for FR2 in the first embodiment is shown in Table 10 below, and the relative quantity mapping table for FR2 is shown in Table 11 below.

[0065] RSTD Report Mapping for FR2

[0066] Report Value Measured Quantity Value Unit RSTD_0000 -15391 > RSTD 16Tc RSTD_0001 -15391 ≤ RSTD < -15386 16Tc … … … RSTD_2258 -4106 ≤ RSTD < -4101 16Tc RSTD_2259 -4101 ≤ RSTD < -4096 16Tc RSTD_2260 -4096 ≤ RSTD < -4095 16Tc RSTD_2261 -4095 ≤ RSTD < -4094 16Tc … … … RSTD_6353 -3 ≤ RSTD < -2 16Tc RSTD_6354 -2 ≤ RSTD < -1 16Tc RSTD_6355 -1 ≤ RSTD < 0 16Tc RSTD_6356 0 < RSTD ≤ 1 16Tc RSTD_6357 1 < RSTD ≤ 2 16Tc RSTD_6358 2 < RSTD ≤ 3 16Tc … … … RSTD_10450 4094 < RSTD ≤ 4094 16Tc RSTD_10451 4095 < RSTD ≤ 4096 16Tc RSTD_10452 4096 < RSTD ≤ 4101 16Tc RSTD_10453 4101 < RSTD ≤ 4106 16Tc … … RSTD_12709 15381 < RSTD ≤ 15386 16Tc RSTD_12710 15386 < RSTD ≤ 15391 16Tc RSTD_12711 15391<RSTD 16Tc

[0067] Table 10 Relative Quantity Mapping for FR2

[0068]

[0069]

[0070] Table 11

[0071] For FR2, the UE will report the reference quantity based on Table 10 and the relative quantity defined in Table 11 such that the difference between the measured RSTD quantity and the lower limit of the corresponding range from Table 10 is between Δ RSTD and Δ RSTD + resolutionStep. resolutionStep is 4Tc for 60kHz SCS in range 2 and 2Tc for 120kHz SCS in range 2, and 8Tc for 60kHz SCS and 4Tc for 120kHz SCS in ranges 1 and 3.

[0072] The above first embodiment standardizes five cases of the RSTD report mapping table. Standardizing the five cases is somewhat complex, but achieves a quantization gain for more accurate reporting. A simpler RSTD report mapping table with reduced complexity and maintaining a relatively good quantization gain is described below in the second embodiment.

[0073] According to the second exemplary embodiment, the RSTD mapping table is defined by frequency band. In other words, the table differentiates between FRs and selects the finest or worst granularity within each FR. If RSTD measurements are performed between FR1 and FR2, the UE can follow the FR1 granularity report, i.e., the coarser granularity. The basic granularity of the RSTD report mapping table is 16Tc for FR1 and 4Tc for FR2. For the second range of RSTD report values, the oversampling rate can be set to 2, similar to the above first embodiment, so the granularity after oversampling is 8Tc for the second range in FR1 and 2Tc for the second range in FR2. For FR1, for the reasons described above, 64Tc is used as the baseline unit for RSTD report mapping, while for FR2, 16Tc is used as the baseline unit.

[0074] The RSTD reporting mapping table for FR1 in the second embodiment is shown in Table 12 below, and the relative quantity mapping table for FR1 is shown in Table 13 below.

[0075] RSTD Report Mapping for FR1

[0076] Report Value Measured Quantity Value Unit RSTD_0000 -15391 > RSTD 64Tc RSTD_0001 -15391 ≤ RSTD < -15386 64Tc … … … RSTD_2258 -4106 ≤ RSTD < -4101 64Tc RSTD_2259 -4101 ≤ RSTD < -4096 64Tc RSTD_2260 -4096 ≤ RSTD < -4095 64Tc RSTD_2261 -4095 ≤ RSTD < -4094 64Tc … … … RSTD_6353 -3 ≤ RSTD < -2 64Tc RSTD_6354 -2 ≤ RSTD < -1 64Tc RSTD_6355 -1 ≤ RSTD < 0 64Tc RSTD_6356 0 < RSTD ≤ 1 64Tc RSTD_6357 1 < RSTD ≤ 2 64Tc RSTD_6358 2 < RSTD ≤ 3 64Tc … … … RSTD_10450 4094 < RSTD ≤ 4094 64Tc RSTD_10451 4095 < RSTD ≤ 4096 64Tc RSTD_10452 4096 < RSTD ≤ 4101 64Tc RSTD_10453 4101 < RSTD ≤ 4106 64Tc … … … RSTD_12709 15381 < RSTD ≤ 15386 64Tc RSTD_12710 15386 < RSTD ≤ 15391 64Tc RSTD_12711 15391<RSTD 64Tc

[0077] Table 12

[0078] Relative Quantity Mapping for FR1

[0079]

[0080]

[0081] Table 13

[0082] For FR1, the UE will report the reference quantity based on Table 12 and the relative quantity defined in Table 13 such that the difference between the measured RSTD quantity and the lower limit of the corresponding range from Table 12 is between Δ RSTD and Δ RSTD + resolutionStep. resolutionStep is 8Tc in the second range and 16Tc in the first and third ranges.

[0083] The RSTD reporting mapping table for FR2 in the second embodiment is shown in Table 14 below, and the relative quantity mapping table for FR2 is shown in Table 15 below.

[0084] RSTD Report Mapping for FR2

[0085]

[0086]

[0087] Table 14 Relative Quantity Mapping for FR2

[0088]

[0089]

[0090] Table 15

[0091] For FR2, the UE will report the reference quantity based on Table 14 and the relative quantity defined in Table 15 such that the difference between the measured RSTD quantity and the lower limit of the corresponding range from Table 15 is between Δ RSTD and Δ RSTDbetween +resolutionStep. resolutionStep is 2Tc in the second range and 4Tc in the first and third ranges.

[0092] Thus, the first and second embodiments provide a relatively simple and accurate reporting framework for RSTD values. According to the third embodiment, the RSTD reporting table can be differentiated by all three of the aforementioned factors affecting granularity, namely FR, SCS, and BW (recall Table 5 discussed above). The reporting mapping table in this embodiment will allow the UE to differentiate the accuracy performance associated with different BW sizes. A table for the third embodiment is not included herein, but those skilled in the art will understand how to construct a table based on the principles described herein for constructing the tables of the first and second embodiments.

[0093] Figure 4 A method 400 for RSTD measurement reporting mapping for UE positioning in 5G NR implemented at the UE is shown. The UE can be the UE 110 discussed above with respect to Figures 1 to 3 discussed.

[0094] At 405, the UE receives PRS from at least three network cells. The network cells can be the gNBs 120A - 120C discussed above with respect to Figure 3 discussed.

[0095] At 410, the UE determines at least the frequency band used by each network cell to transmit the PRS. As described above in the second exemplary embodiment, the UE can differentiate by frequency band. In other embodiments, the UE can determine the SCS (according to the first exemplary embodiment) and / or BW (according to the third exemplary embodiment) for each of the PRSs.

[0096] At 415, the UE determines the RSTD value of the PRS and correlates the RSTD value with the RSTD reporting value from the appropriate RSTD reporting mapping table. In this embodiment, if only FR is used, the UE will use Table 12 or 14 to determine the RSTD reporting value.

[0097] At 420, the UE determines the relative quantity value of the PRS and correlates the relative quantity value with the relative quantity reporting value from the appropriate RSTD quantity mapping table. In this embodiment, if only FR is used, the UE will use Table 13 or 15 to determine the relative quantity value.

[0098] At 425, the UE transmits an indication of the determined RSTD reporting value and relative quantity value to the network. The UE can transmit this indication to any base station from which it receives the PRS or can transmit the indication in another way. Based on the reported values, the network can determine the location of the UE according to the OTDOA procedure.

[0099] Those skilled in the art will understand that the above-described exemplary embodiments can be implemented with any suitable software configuration or hardware configuration or a combination thereof. Exemplary hardware platforms for implementing the exemplary embodiments may include, for example, Intel x86-based platforms with compatible operating systems, Windows OS, Mac platforms and MAC OS, mobile devices with operating systems such as iOS, Android, etc. In other examples, the exemplary embodiments of the above methods may be embodied as programs including lines of code stored on a non-transitory computer-readable storage medium, which, when compiled, can be executed on a processor or microprocessor.

[0100] Although this patent application describes various combinations of various embodiments each having different features, those skilled in the art will understand that any feature of one embodiment can be combined with the features of other embodiments in any manner not precluded by the disclosure or features that are not functionally or logically inconsistent with the operation of the devices of the embodiments disclosed in the present invention or the said functions.

[0101] It is well known that the use of personally identifiable information should follow privacy policies and practices that are recognized as meeting or exceeding industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of inadvertent or unauthorized access or use, and the nature of the authorized use should be clearly explained to users.

[0102] It will be apparent to those skilled in the art that various modifications can be made to the present disclosure without departing from the essence or scope of the present disclosure. Therefore, the present disclosure is intended to cover modifications and variations of the present disclosure, provided that these modifications and variations are within the scope of the appended claims and their equivalents.

Claims

1. A method for reference signal time difference (RSTD) measurement report mapping, comprising: Performing the following operations at a user equipment (UE) configured to establish a connection with a network, the network including a first cell and a second cell: Receiving positioning reference signals from each of the first cell and the second cell; Determining a first frequency band of the positioning reference signal of the first cell, wherein the first frequency band is within FR1, and FR1 refers to frequency range 1; Determining a second frequency band of the positioning reference signal of the second cell, wherein the second frequency band is within FR2, and FR2 refers to frequency range 2; Determining an RSTD value from a measurement time offset between the positioning reference signals from the first cell and the second cell; Selecting a reporting granularity associated with FR1 in response to the RSTD measurement being performed between FR1 and FR2; Using an RSTD report mapping table to determine an RSTD report value based at least on the RSTD value, the determined frequency bands, and the reporting granularity associated with FR1, wherein the RSTD report mapping table is defined according to frequency bands; and Transmitting an indication of the RSTD report value to the network.

2. The method according to claim 1, further comprising: Determining a relative quantity value of the positioning reference signals; Determining a relative quantity report value based at least on the determined relative quantity value; And Transmitting an indication of the relative quantity report value to the network; Wherein the relative quantity value and the relative quantity report value are pre-determined in a predetermined table, and in the predetermined table, each relative quantity value is associated with a corresponding relative quantity report value.

3. The method according to claim 2, wherein the relative quantity report value is further based on the granularity of the RSTD value.

4. The method according to claim 2, wherein the relative quantity report value is further based on the oversampling rate of the positioning reference signal.

5. The method according to claim 1, further comprising: Determining a subcarrier spacing of each of the positioning reference signals, and the report value is further determined based on the determined subcarrier spacing.

6. The method according to claim 5, further comprising: Determining a bandwidth of each of the positioning reference signals, and the report value is further determined based on the determined bandwidth.

7. The method according to claim 6, wherein when the positioning reference signals from the first cell and the second cell have a difference in one of the frequency band, subcarrier spacing, or bandwidth, the report value includes the report value with the coarsest granularity of the positioning reference signals.

8. A user equipment (UE), comprising: A transceiver configured to establish a connection with a network, the network including a first cell and a second cell, the transceiver receiving positioning reference signals from each of the first cell and the second cell; And A processor, the processor being configured to: determine a first frequency band of the positioning reference signal of the first cell, wherein the first frequency band is within FR1, and FR1 refers to frequency range 1; determine a second frequency band of the positioning reference signal of the second cell, wherein the second frequency band is within FR2, and FR2 refers to frequency range 2; in response to a reference signal time difference (RSTD) measurement being performed between FR1 and FR2, select a reporting granularity associated with FR1; determine an RSTD value from a measurement time offset between the positioning reference signals from the first cell and the second cell; and determine an RSTD reporting value using an RSTD reporting mapping table based at least on the RSTD value, the determined frequency bands, and the reporting granularity associated with FR1, wherein the RSTD reporting mapping table is defined according to frequency bands, wherein the transceiver transmits an indication of the RSTD reporting value to the network.

9. The UE according to claim 8, wherein the processor further determines a relative quantity value of the positioning reference signal, and determines a relative quantity report value based at least on the determined relative quantity value, and the transceiver transmits an indication of the relative quantity report value to the network, wherein The relative quantity value and the relative quantity reporting value are pre-determined in a predetermined table, and in the predetermined table, each relative quantity value is associated with a corresponding relative quantity reporting value.

10. The UE according to claim 9, wherein the relative quantity reporting value is further based on the granularity of the RSTD value.

11. The UE according to claim 9, wherein the relative quantity reporting value is further based on the oversampling rate of the positioning reference signal.

12. The UE according to claim 8, wherein the processor further determines the subcarrier spacing of each of the positioning reference signals, and the reporting value is further determined based on the determined subcarrier spacing.

13. The UE according to claim 12, wherein the processor further determines the bandwidth of each of the positioning reference signals, and the reporting value is further determined based on the determined bandwidth.

14. The UE according to claim 8, wherein the network is a 5G NR radio access network.

15. An integrated circuit, comprising: a circuit configured to establish a connection with a network, the network including a first cell and a second cell; a circuit configured to receive positioning reference signals from each of the first cell and the second cell; a circuit configured to determine a first frequency band of the positioning reference signal of the first cell, wherein the first frequency band is within FR1, and FR1 refers to frequency range 1; a circuit configured to determine a second frequency band of the positioning reference signal of the second cell, wherein the second frequency band is within FR2, and FR2 refers to frequency range 2; a circuit configured to determine a reference signal time difference (RSTD) value from a measurement time offset between the positioning reference signals from the two cells; a circuit configured to select a reporting granularity associated with FR1 in response to an RSTD measurement being performed between FR1 and FR2; a circuit configured to determine an RSTD reporting value using an RSTD reporting mapping table based at least on the RSTD value, the determined frequency bands, and the reporting granularity associated with FR1, wherein the RSTD reporting mapping table is defined according to frequency bands; and A circuit for transmitting an indication of the RSTD report value to the network.

16. The integrated circuit according to claim 15, further comprising: A circuit configured to determine a relative quantity value of the positioning reference signal; A circuit configured to determine a relative quantity report value based at least on the determined relative quantity value; And A circuit configured to transmit an indication of the relative quantity report value to the network; Wherein the relative quantity value and the relative quantity report value are pre-determined in a predetermined table, and in the predetermined table, each relative quantity value is associated with a corresponding relative quantity report value.

17. The integrated circuit according to claim 16, wherein the relative quantity report value is further based on the granularity of the RSTD value.

18. The integrated circuit according to claim 15, further comprising: A circuit configured to determine a subcarrier spacing of each of the positioning reference signals, and the report value is further determined based on the determined subcarrier spacing.

19. The integrated circuit according to claim 18, further comprising: A circuit configured to determine a bandwidth of each of the positioning reference signals, and the report value is further determined based on the determined bandwidth.

20. The integrated circuit according to claim 19, wherein when the positioning reference signals from the first cell and the second cell have a difference in one of the frequency band, subcarrier spacing, or bandwidth, the report value includes the report value with the coarsest granularity of the positioning reference signal.

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