Position estimation for non-terrestrial networks

Abstract

A method is provided, comprising: measuring a first time of arrival (TOA) of a first signal from a first satellite, a second TOA of a second signal from a second satellite, and a third TOA of a third signal from a third satellite during a period of time; after the period of time has elapsed, reporting the first TOA together with a first cell identifier and a first parameter allowing the derivation of the transmission time of the first signal, the second TOA together with a second cell identifier and a second parameter enabling the derivation of the transmission time of the second signal, and the third TOA together with a third cell identifier and a third parameter allowing the derivation of the transmission time of the third signal, wherein the first TOA is measured within a first interval set in the period of time; the second TOA is measured within a second interval set in the period of time; and the second interval does not overlap with the first interval.

Description

Technical Field

[0001] The present invention relates to position estimation.

[0002] Abbreviations

[0003] 3GPP Third Generation Partnership Project

[0004] 3G / 4G / 5G Third / Fourth / Fifth Generation

[0005] AoA Angle of Arrival

[0006] ARFCN Absolute Radio Frequency Channel Number

[0007] BS Base Station

[0008] CU 5G NR gNB Central Unit

[0009] DRMS demodulation reference signal

[0010] DU 5G NR gNB Distributed Unit

[0011] ECGI E-UTRAN Cell Global Identifier

[0012] eNB Evolved Node B (base station in 4G)

[0013] E-SMLC Enhanced SMLC

[0014] FDD Frequency Division Duplex

[0015] GEO Geostationary Orbit Satellite

[0016] GMLC Gateway Mobile Location Center

[0017] gNB Base Station in 5G / NR

[0018] GNSS Global Navigation Satellite System

[0019] GPS Global Positioning System

[0020] HAPS High Altitude Platform System

[0021] HD-FDD Half-duplex FDD

[0022] ID Identity, identifier

[0023] IoT

[0024] LEO Low Earth Orbit Satellite

[0025] LMU Position Measurement Unit

[0026] MEO Medium Orbit Satellite

[0027] MIB Master Information Block

[0028] MME Mobility Management Entity

[0029] MTC Machine Type Communication

[0030] NR New Radio

[0031] NTN Non-Terrestrial Network

[0032] OTDOA Observation TDOA

[0033] PBCH Physical Broadcast Channel

[0034] PCI Physical Cell Identifier

[0035] PDN Packet Data Network

[0036] PSS Primary Synchronization Signal

[0037] RAN Radio Access Network

[0038] RRC Radio Resource Control

[0039] RSTD Reference Signal Time Difference

[0040] Rx

[0041] SFN System Frame Number

[0042] SIB1 System Information Block 1

[0043] SIB16 System Information Block 16

[0044] SLP SUPL Location Platform

[0045] SMLC Service Mobile Location Center

[0046] SRS Sounding Reference Signal

[0047] SS Synchronization Sequence

[0048] SSS Secondary synchronization signal

[0049] SSB synchronization signal and PBCH block

[0050] SUPL Secure User Plane Location

[0051] TAU Tracking Area Updates

[0052] TDOA Time Difference of Arrival

[0053] TOA Time of Arrival

[0054] TR Technical Report

[0055] TS Technical Specifications

[0056] TX

[0057] UAS

[0058] UE User Equipment

[0059] UTDOA Uplink TDOA Background Art

[0060] 3GPP non-terrestrial network (e.g. in 5G NR) deployments and services must comply with existing satellite communications regulations and rules. One of such regulations is that satellite connectivity / service provision depends on user equipment (UE) registration and geographic location, i.e., they must comply with requirements in certain countries or regions of the world where Internet access is limited or absent. If Internet access can be provided via satellite, these requirements must also be met.

[0061] Furthermore, NTN may apply different charging policies for different countries, national authorities may require the possibility of lawful interception, and different countries may need to provide or ban certain services. Finally, there are international domains such as maritime where another set of policies may apply. This has been described in 3GPP R3-186661, which is discussed in the context of NR for NTN study items in 3GPP TR 38.821.

[0062] Note that knowing the location of a UE at a country / geographical region level requires fairly high accuracy, since UEs may be close to borders and some countries are quite small.

[0063] An obvious way to solve the above problem is to use the GNSS position information of the UE. In satellite communications, it is usually assumed that all satellite UEs have GNSS capabilities. However,

[0064] i) it is expected that in the future not all NTN UEs will have GNSS receivers (e.g. low-cost IoT devices), and / or

[0065] ii) It is generally accepted that GNSS positions can be scrambled or even falsified (see, for example, the aviation industry)

[0066] In the case of 5G NR NTN, we expect that the location services specified by 3GPP will be available and these services can provide a nearly 3D position of the UE (taking into account several satellites and orbits). One disadvantage of this approach is that it requires the UE to be in RRC_CONNECTED / ACTIVE mode to send location measurement information back to the serving cell. This involves significant latency and higher radio resource consumption.

[0067] Position / location services in 3GPP terrestrial networks are usually based on Observed Time Difference of Arrival (OTDOA). This position estimate is based on the Time Difference of Arrival (TDOA) measured by the UE from specific reference signals received from different eNBs and embedded in the overall downlink signal. Each TDOA measurement describes a hyperbola where the two foci (F1, F2) are the foci of the two measured eNBs. The measurements need to be performed for at least three pairs of base stations. The location of the device is the intersection of the three hyperbolas of the three measured base stations A, B and C (based on the hyperbolas of time differences AB, AC and BC; see Figure 1 ).

[0068] The measurement made between a pair of eNBs is defined as the Reference Signal Time Difference (RSTD) [3GPP TS36.214]. The measurement is defined as the relative timing difference between a subframe received from a neighbor cell j and the corresponding subframe received from a serving cell i:

[0069]

[0070] Table 1: Definition of RSTD

[0071] These measurements are made on the Positioning Reference Signal. The results are reported back to the Location Server which can calculate the position of the UE. More information can be found at http:

[0072] / / www.qualcomm.com / media / documents / files / otdoa-positioning-in-3gpp-lte.pdf.

[0073] 3GPP has defined an architecture for location services. A simplified version is available in Figure 2 The location server (E-SMLC or SLP) manages OTDOA positioning for the target device by obtaining RSTD measurements from the UE and providing assistance data to the UE to help the UE determine RSTD. The GMLC is the first node in the control plane positioning, which performs registration and authorization.

[0074] The whole process generally runs as follows (partially taken from https: / / www.qualcomm.com / media / documents / files / otdoa-positioning-in-3gpp-lte.pdf):

[0075] In the control plane solution, the MME receives a request for some location services associated with a specific target UE from another entity (e.g., GMLC or UE), or the MME itself decides to initiate some location services on behalf of a specific target UE (e.g., for an IMS emergency call from the UE), as described in 3GPP TS 23.271

[11] . The MME then sends a location service request to the E-SMLC. The E-SMLC processes the location service request, including transmitting OTDOA assistance data to the target UE. The E-SMLC then returns the result of the location service to the MME. In the case where the location service is requested by an entity other than the MME (e.g., UE or GMLC), the MME returns the location service result to that entity.

[0076] The UE report contains the following information:

[0077] 1. The timestamp of the measurement is set in the form of SFN.

[0078] 2. Identity of the reference cell used to calculate RSTD (PCI, ARFCN and / or ECGI)

[0079] 3. The quality of TOA measurements from the reference cell.

[0080] 4. Neighbor cell measurements from reference cells

[0081] o The identity of the measured neighbor cell (PCI, ARFCN and / or ECGI)

[0082] οRSTD measurement (see above)

[0083] οQuality of RSTD measurements

[0084] As another option to determine the position of the UE, satellite service tracking / service area management is known: it is recognized in 3GPP that a tracking area / service area contains information about the position on the earth, as it is known in which satellite beam the UE is (or has been) in. However, this positioning is very coarse and inaccurate information.

[0085] As an alternative to UE-based measurements, the network side may determine the UE's location based on various measurements performed by the network:

[0086] UTDOA: Uplink Relative Time Difference of Arrival measurement, where multiple eNBs time-stamp the received reference signals and the E-SMLC calculates the UE position similar to OTDOA based on this reception timing and the known eNB locations.

[0087] Round Trip Time: The eNB measures the Tx to Rx time difference between a downlink signal sent to a UE and the received uplink signal of the same UE. This combined with knowledge of the UE's Rx to Tx time difference, either based on UE measurements or defined UE timing can be used to determine the actual signal air propagation delay, and therefore the distance between the UE and the eNB.

[0088] Angle of arrival: An eNB with an antenna array can estimate the received signal direction, and this information can be used to determine the UE's location.

[0089] Some definitions of 3GPP TS 36.214 for LTE are indicated in Tables 2 to 5:

[0090]

[0091] Table 2: Definition of UL-RTOA

[0092]

[0093] Table 3: Definition of AoA

[0094]

[0095] Table 4: Definition of round trip time triggered by eNB

[0096]

[0097] Table 5: Definition of round trip time triggered by UE

[0098] NTN platforms may include any of the following types:

[0099]

[0100]

[0101] Table 6: NTN platform

[0102] For LEO, the satellite's relative speed with respect to the Earth is approximately several kilometers per second, for example, about 7 to 8 km per second.

[0103] When the UE is in RRC_IDLE mode, it sends a TAU report when it leaves its current tracking area, or when the UE sends a periodic TAU request message (TAU report), it sends a TAU report without leaving the current tracking area. Summary of the invention

[0104] The object of the present invention is to improve the prior art.

[0105] According to a first aspect of the present invention, there is provided an apparatus comprising:

[0106] means for measuring, configured to measure, during a reporting period, a first absolute time of arrival of a first signal from a first satellite identified by a first cell identifier, a second absolute time of arrival of a second signal from a second satellite identified by a second cell identifier, and a third absolute time of arrival of a third signal from a third satellite identified by a third cell identifier;

[0107] Means for reporting, configured to report, after a reporting period has elapsed, an indication of a first absolute time of arrival together with a first cell identifier and a first parameter, an indication of a second absolute time of arrival together with a second cell identifier and a second parameter, and an indication of a third absolute time of arrival together with a third cell identifier and a third parameter, the first parameter allowing derivation of an absolute time of transmission of the first signal, the second parameter allowing derivation of an absolute time of transmission of the second signal, and the third parameter allowing derivation of an absolute time of transmission of the third signal, wherein

[0108] The means for measuring is configured to measure a first absolute arrival time within a first measurement interval set in a reporting period;

[0109] The means for measuring is configured to measure a second absolute arrival time within a second measurement interval set in the reporting period;

[0110] The second measurement interval does not overlap with the first measurement interval.

[0111] According to a second aspect of the present invention, there is provided an apparatus comprising:

[0112] means for measuring, configured to measure, during a reporting period, a first received power of a first signal from a first satellite identified by a first cell identifier, a second received power of a second signal from a second satellite identified by a second cell identifier, and a third received power of a third signal from a third satellite identified by a third cell identifier;

[0113] Means for reporting, configured to report, after a reporting period has elapsed, an indication of a first received power together with a first cell identifier, a first absolute time when the first received power was measured and a first parameter, an indication of a second received power together with a second cell identifier, a second absolute time when the second received power was measured and a second parameter, and an indication of a third received power together with a third cell identifier, a third absolute time when the third received power was measured and a third parameter, the first parameter allowing to derive an absolute transmission time of the first signal, the second parameter allowing to derive an absolute transmission time of the second signal, and the third parameter allowing to derive an absolute transmission time of the third signal, wherein

[0114] The means for measuring is configured to measure a first received power within a first measurement interval set in a reporting period;

[0115] The means for measuring is configured to measure a second received power within a second measurement interval set in the reporting period;

[0116] The second measurement interval differs from the first measurement interval by a minimum time interval.

[0117] According to a third aspect of the present invention, there is provided an apparatus, comprising:

[0118] a component for measuring, configured to measure, within a set first measurement interval during a set reporting period, at least one of a first arrival time of a first signal from the terminal, a first arrival angle of a second signal from the terminal, and a first round-trip time of a third signal from the terminal, and configured to measure, within a set second measurement interval during the reporting period, at least one of a second arrival time of a fourth signal from the terminal, a second arrival angle of a fifth signal from the terminal, and a second round-trip time of a sixth signal from the terminal;

[0119] Means for reporting, configured to report, after a reporting period has elapsed, an identification of the terminal, including an identification of a satellite of the device, an indication of the measured at least one of a first arrival time, a first arrival angle, and a first round trip time together with an identification of a corresponding at least one of the first signal, the second signal, and the third signal and a corresponding first absolute measurement time when the corresponding at least one of the first arrival time, the first arrival angle, and the first round trip time was measured, and an indication of the measured at least one of a second arrival time, a second arrival angle, and the second round trip time together with an identification of a corresponding at least one of the fourth signal, the fifth signal, and the sixth signal and a corresponding second absolute measurement time when the corresponding at least one of the second arrival time, the second arrival angle, and the second round trip time was measured, wherein

[0120] The first measurement interval does not overlap with the second measurement interval.

[0121] According to a fourth aspect of the present invention, there is provided an apparatus, comprising:

[0122] means for obtaining, configured to obtain, for each of a plurality of pairs of an indication of a respective absolute time of arrival of a respective signal from a respective satellite and a respective satellite identity, a respective location of the respective satellite based on information about an orbit of the respective satellite;

[0123] A component for estimating is configured to estimate the location of the terminal based on the obtained multiple locations and the related multiple location data sets, wherein

[0124] For each of the plurality of pairs of corresponding absolute arrival times and corresponding satellite identities, the corresponding satellite is identified by the corresponding satellite identity;

[0125] Each position data set of the plurality of position data sets comprises a respective absolute arrival time and respective parameters, the respective parameters allowing to derive an absolute sending time of the respective signal;

[0126] And at least one of the absolute arrival times is different from another one of the absolute arrival times.

[0127] According to a fifth aspect of the present invention, there is provided an apparatus, comprising:

[0128] means for obtaining, configured to obtain, for each of a plurality of pairs of an indication of a respective absolute measurement time of a received power of a respective signal from a respective satellite and a respective satellite identity, a respective position of the respective satellite based on information about an orbit of the respective satellite;

[0129] A component for estimating is configured to estimate the location of the terminal based on the obtained multiple locations and the related multiple location data sets, wherein

[0130] For each of the plurality of pairs of corresponding absolute measurement times and corresponding satellite identities, the corresponding satellite is identified by the corresponding satellite identity;

[0131] Each position data set of the plurality of position data sets comprises a respective absolute measurement time and a respective parameter, the respective parameter allowing to derive a transmission power of the respective signal;

[0132] And at least one of the absolute measurement times is different from another one of the absolute measurement times.

[0133] According to a sixth aspect of the present invention, there is provided an apparatus, comprising:

[0134] means for checking, configured to check whether location information for a terminal including the device is available;

[0135] means for providing, configured to provide the location information to the network together with a tracking area update report of the terminal if the location information is available, wherein

[0136] The location information enables the location of the terminal to be determined more accurately than on a cell level; and

[0137] The terminal is in idle mode.

[0138] According to a seventh aspect of the present invention, there is provided an apparatus, comprising:

[0139] A means for checking, configured to check whether the tracking area update report received from the terminal includes the location information of the terminal;

[0140] The forwarding component is configured to forward the terminal's identifier and location information to a location server if the tracking area update report includes location information, wherein

[0141] The location information allows the position of the terminal to be determined more accurately than on cell level.

[0142] According to an eighth aspect of the present invention, there is provided a method comprising:

[0143] measuring, during a reporting period, a first absolute time of arrival of a first signal from a first satellite identified by a first cell identifier, a second absolute time of arrival of a second signal from a second satellite identified by a second cell identifier, and a third absolute time of arrival of a third signal from a third satellite identified by a third cell identifier;

[0144] reporting, after the reporting period has elapsed, an indication of a first absolute time of arrival together with a first cell identifier and a first parameter, an indication of a second absolute time of arrival together with a second cell identifier and a second parameter, and an indication of a third absolute time of arrival together with a third cell identifier and a third parameter, the first parameter allowing derivation of an absolute time of transmission of the first signal, the second parameter allowing derivation of an absolute time of transmission of the second signal, and the third parameter allowing derivation of an absolute time of transmission of the third signal, wherein

[0145] The first absolute arrival time is measured within a first measurement interval set in the reporting period;

[0146] The second absolute arrival time is measured within a second measurement interval set in the reporting period;

[0147] The second measurement interval does not overlap with the first measurement interval.

[0148] According to a ninth aspect of the present invention, there is provided a method comprising:

[0149] measuring, during a reporting period, a first received power of a first signal from a first satellite identified by a first cell identifier, a second received power of a second signal from a second satellite identified by a second cell identifier, and a third received power of a third signal from a third satellite identified by a third cell identifier;

[0150] After a reporting period has elapsed, reporting a first received power together with a first cell identifier, an indication of a first absolute time when the first received power was measured, and a first parameter, a second received power together with a second cell identifier, an indication of a second absolute time and a second parameter when the second received power was measured, and a third received power together with a third cell identifier, an indication of a third absolute time when the third received power was measured, and a third parameter, the first parameter enabling the derivation of an absolute transmission time of the first signal, the second parameter enabling the derivation of an absolute transmission time of the second signal, and the third parameter enabling the derivation of an absolute transmission time of the third signal, wherein

[0151] The first received power is measured within a first measurement interval set in the reporting period;

[0152] The second received power is measured within a second measurement interval set in the reporting period;

[0153] The second measurement interval differs from the first measurement interval by a minimum time interval.

[0154] According to a tenth aspect of the present invention, there is provided a method, comprising:

[0155] measuring, within a set first measurement interval during a set reporting period, at least one of a first arrival time of a first signal from the terminal, a first arrival angle of a second signal from the terminal, and a first round-trip time of a third signal from the terminal; and measuring, within a set second measurement interval during the reporting period, at least one of a second arrival time of a fourth signal from the terminal, a second arrival angle of a fifth signal from the terminal, and a second round-trip time of a sixth signal from the terminal;

[0156] After the reporting period has elapsed, reporting an identification of the terminal, including an identification of a satellite of the device, an indication of the measured at least one of a first time of arrival, a first angle of arrival, and a first round trip time together with an identification of a corresponding at least one of the first signal, the second signal, and the third signal and a corresponding first absolute measurement time when the corresponding at least one of the first time of arrival, the first angle of arrival, and the first round trip time was measured, and an indication of the measured at least one of a second time of arrival, a second angle of arrival, and the second round trip time together with an identification of a corresponding at least one of the fourth signal, the fifth signal, and the sixth signal and a corresponding second absolute measurement time when the corresponding at least one of the second time of arrival, the second angle of arrival, and the second round trip time was measured, wherein

[0157] The first measurement interval does not overlap with the second measurement interval.

[0158] According to an eleventh aspect of the present invention, there is provided a method comprising:

[0159] obtaining, for each of a plurality of pairs of an indication of a respective absolute measurement time of received power of a respective signal from a respective satellite and a respective satellite identity, a respective position fix for the respective satellite based on the information regarding the orbit of the respective satellite;

[0160] The location of the terminal is estimated based on the obtained multiple locations and the associated multiple location data sets, wherein

[0161] For each of the plurality of pairs of corresponding absolute measurement times and corresponding satellite identities, the corresponding satellite is identified by the corresponding satellite identity;

[0162] Each position data set of the plurality of position data sets comprises a respective absolute measurement time and a respective parameter, the respective parameter allowing to derive a transmission power of the respective signal;

[0163] And at least one of the absolute measurement times is different from another one of the absolute measurement times.

[0164] According to a twelfth aspect of the present invention, there is provided a method, comprising:

[0165] obtaining, for each of a plurality of pairs of an indication of a respective absolute measurement time of received power of a respective signal from a respective satellite and a respective satellite identity, a respective position fix for the respective satellite based on the information regarding the orbit of the respective satellite;

[0166] The location of the terminal is estimated based on the obtained multiple locations and the associated multiple location data sets, wherein

[0167] For each of the plurality of pairs of corresponding absolute measurement times and corresponding satellite identities, the corresponding satellite is identified by the corresponding satellite identity;

[0168] Each position data set of the plurality of position data sets comprises a respective absolute measurement time and a respective parameter, the respective parameter allowing to derive a transmission power of the respective signal;

[0169] And at least one of the absolute measurement times is different from another one of the absolute measurement times.

[0170] According to a thirteenth aspect of the present invention, there is provided a method comprising:

[0171] checking whether location information for a terminal including an apparatus for performing the method is available;

[0172] If location information is available, the location information is provided to the network together with the terminal's tracking area update report, where

[0173] The location information enables the location of the terminal to be determined more accurately than on a cell level; and

[0174] The terminal is in idle mode.

[0175] According to a fourteenth aspect of the present invention, there is provided a method, comprising:

[0176] checking whether the tracking area update report received from the terminal includes the location information of the terminal;

[0177] If the tracking area update report includes location information, the terminal's identification and location information are forwarded to the location server, where

[0178] The location information enables the location of the terminal to be determined more accurately than on a cell level.

[0179] Each of the methods of the eighth to fourteenth aspects may be a method for position estimation.

[0180] According to a fifteenth aspect of the present invention, a computer program product comprises an instruction set, which, when executed on a device, is configured to cause the device to perform a method according to any one of the eighth to fourteenth aspects. The computer program product may be implemented as a computer-readable medium or may be directly loaded into a computer.

[0181] According to some example embodiments of the present invention, at least one of the following advantages may be achieved:

[0182] The location of the UE can be determined based on 3GPP mechanisms;

[0183] NTN operators do not need to rely on a GNSS receiver implemented in the NTN UE, and do not need to rely on GNSS position information reported by the UE (this position method can actually be turned off with the push of a button in some existing satellite phones);

[0184] UE location can be used to comply with local / regional regulations regarding the use of satellite terminals;

[0185] The position of the UE may be estimated when the UE is in IDLE mode, i.e. before possibly entering RRC ACTIVE / CONNECTED mode;

[0186] The UE energy consumption required to provide location reporting is significantly reduced compared to the location mechanism using RRC ACTIVE / CONNECTED mode reporting;

[0187] No GNSS receiver and GNSS position information required

[0188] Location information can be provided when needed (not necessarily on a periodic basis);

[0189] The achieved UE positioning accuracy can be controlled by the NTN operator (via TAU periodicity and location measurement reporting parameters). It may be different in different regions, thus also complying with privacy laws;

[0190] • The mechanism is not specific to a given satellite constellation type and can be customized to work for any HAPS / LEO / MEO / GEO architecture.

[0191] It should be understood that any of the above modifications may be applied individually or in combination to the corresponding aspects to which they relate, unless they are explicitly stated as excluded alternatives. BRIEF DESCRIPTION OF THE DRAWINGS

[0192] Further details, features, objects and advantages will be apparent from the following detailed description of preferred exemplary embodiments of the present invention taken in conjunction with the accompanying drawings, in which:

[0193] Figure 1 The principle of TDOA measurement based on hyperbola is shown, taken from http:

[0194] / / www.rohde-schwarz-wireless.com / documents / LTELBSWhitePaper_RohdeSchwarz.pdf

[0195] Figure 2 The 3GPP location services architecture is shown;

[0196] Figure 3 illustrates examples of timing and time-related parameters according to some example embodiments of the present invention;

[0197] Figure 4 illustrates examples of timing and time-related parameters according to some example embodiments of the present invention;

[0198] Figure 5 The principles of cell measurement for positioning purposes at the NTN UE side using SS / PBCH and MIB decoding sent by different satellites according to some example embodiments of the present invention are shown;

[0199] Figure 6 An apparatus according to an example embodiment of the present invention is shown;

[0200] Figure 7 A method according to an example embodiment of the present invention is shown;

[0201] Figure 8 An apparatus according to an example embodiment of the present invention is shown;

[0202] Fig. 9 A method according to an example embodiment of the present invention is shown;

[0203] Fig.10 An apparatus according to an example embodiment of the present invention is shown;

[0204] Fig.11 A method according to an example embodiment of the present invention is shown;

[0205] Fig.12 An apparatus according to an example embodiment of the present invention is shown;

[0206] Fig.13 A method according to an example embodiment of the present invention is shown;

[0207] Fig.14 An apparatus according to an example embodiment of the present invention is shown;

[0208] Fig.15 A method according to an example embodiment of the present invention is shown;

[0209] Fig.16 An apparatus according to an example embodiment of the present invention is shown;

[0210] Fig.17 A method according to an example embodiment of the present invention is shown;

[0211] Fig.18 An apparatus according to an example embodiment of the present invention is shown;

[0212] Fig.19 A method according to an example embodiment of the present invention is shown; and

[0213] Fig. 20 An apparatus according to an example embodiment of the invention is shown. DETAILED DESCRIPTION

[0214] In the following, some exemplary embodiments of the present invention are described in detail with reference to the accompanying drawings, wherein, unless otherwise specified, the features of the exemplary embodiments may be freely combined with each other. However, it should be clearly understood that the description of some exemplary embodiments is given only as an example, and it is by no means intended to be understood as limiting the present invention to the disclosed details.

[0215] Furthermore, it should be understood that the apparatus is configured to perform the corresponding method, although in some cases only the apparatus or only the method is described.

[0216] The above requirements and regulations mean that the network needs to know where a certain UE is located (in which country, geographical area). Preferably, the network knows the location of the UE before the service is initiated. If the UE is in active mode (RRC_CONNECTED), there are some methods to estimate the location. However, if an inactive UE must enter active mode before the location is determined, this will greatly delay the establishment of the service. Therefore, some example embodiments of the present invention provide methods for determining the positioning of a UE, preferably operating in idle mode, so that the establishment delay is not unnecessarily extended.

[0217] As mentioned above, there are methods for estimating UE positioning for terrestrial networks. However, they rely on the locations of three known static cells, which is straightforward for terrestrial networks. However, when considering low-orbit satellite systems, the cells move relative to the Earth. In addition, the UE can see one low-orbit satellite at a time.

[0218] Preferably, the network is able to accurately determine the location of the UE before the UE becomes RRC_CONNECTED with the network and receives data services, as the network must comply with the above regulations and policies regarding UE services in a specific region / country.

[0219] Some example embodiments of the present invention may use some parts of the location / positioning services in the 3GPP terrestrial network described above. However, in a satellite network, it is usually not possible to see 3 base stations (3 satellites acting as base stations, such as eNBs or gNBs, or at least as "bent pipes" (transparent in 3GPP terminology), i.e. relaying gNB radio transmissions from the earth). In addition, it is recommended that the UE make 3 measurements of the signals from the satellite in at least 2 different orbital planes. In order to overcome this potential problem, according to some embodiments of the present invention, the UE does not report RSTD, but reports TOA and timestamp information.

[0220] Some example embodiments of the present invention provide new mechanisms at the RAN level to help locate NTN UEs with certain spatial granularity without GNSS using tamper-proof radio access signaling. The mechanism can complement existing location / positioning services specified by 3GPP, which are also expected to be available in 5G NR NTN deployments, and the mechanism can also reuse the same architecture. It is particularly suitable for position determination using mobile satellites.

[0221] This method is implemented as follows (see also Figure 3 ):

[0222] 1. The TAU reporting period is configured for UEs in RRC_IDLE mode. Figure 3 The TAU period may be pre-configured or configured by the network.

[0223] 2. The UE measures TOA in multiple measurement intervals during the TAU reporting period (e.g., periodically or event-driven). The measurement intervals do not overlap with each other. Figure 3 In the example, the measurement interval is indicated as a hash rectangle. There are at least two measurement intervals (e.g., 5 measurement intervals, such as Figure 3 ). In each measurement interval, the UE may measure one or more TOAs (absolute time of arrival). The UE is allowed to measure the TOA of the signal from the same satellite several times as long as there is a minimum time period between the measurements. This is to ensure that the satellite has moved far enough to be seen at the new location. Figure 3 In , this minimum time is expressed as the minimum satellite movement period (MinSATMovePeriod). For example, for a LEO satellite at an altitude of 7.5 km / s, the minimum satellite movement period is usually about 4-6 minutes. Figure 3In the TAU period, since the minimum satellite movement period has passed after the first measurement of the TOA of PCI4, the UE can measure the TOA of PCI4 for the second time within the TAU period. The minimum satellite movement period can be predefined or configured by the network. This may depend on the accuracy required for position determination. In the context of the present application, TOA is an absolute time. However, if the absolute time related to the relative time is known, it can be expressed by the relative time. For example, the absolute time can be the time when the satellite sends the received signal, and the relative time can be the time difference between the sending time and the receiving time. There may be only one absolute time for multiple TOAs represented by different relative times.

[0224] 3. The relationship between the absolute time at the UE and the absolute time at the network is clear (at least within the required accuracy) and known to the network. Preferably, the absolute time at the UE is the same as the absolute time at the network. The UE can receive an indication of the absolute time from one of the satellites providing the TOA measurement signal or from another base station (satellite or ground base station). Based on the received absolute time, the UE calculates the absolute time of the UE at a subsequent point in time with the help of the UE internal clock. The UE internal clock should have sufficient time accuracy (small drift).

[0225] 4. Optionally, the UE may be configured with a stop condition. If a stop condition is configured, the UE measures TOA until the stop condition is met. It then stops measuring until the next TAU ​​reporting period begins. Example stop conditions are the minimum number of measurement intervals to measure, the minimum number of TOAs to measure, and the minimum number of different satellites for which TOAs are measured. The minimum number in the stop condition may be predefined or configured by the network. In some example embodiments of the present invention, the network may turn on and off the corresponding stop condition. For example, in Figure 3 In the example, it is assumed that the minimum number of TOA measurements is 3, so that the UE can stop measuring after its second measurement of PCI4. The UE can measure the location reference symbol as done in the existing location service, or the UE can perform cell detection measurements (i.e., SS / PBCH and MIB decoding). The cell ID is stored together with the TOA estimate.

[0226] 5. When the UE sends a TAU request message, a UE indication of the (absolute) TOA from the (potentially different) satellites together with the corresponding identifier of the satellite and some indication enabling the absolute transmission time of the corresponding signal to be obtained (an example of a "position data set") is sent to the network (i.e., the signal measuring the TOA is sent via one of the satellites, or sent to the MME via another satellite or directly to the location server). In some example embodiments, if the TOA is indicated as a corresponding time, the report may include a corresponding indication of the absolute time for each TOA. Examples of indications enabling the transmission time to be obtained may be the transmission time itself, or an indication of the corresponding signal. In the latter case, the location server may obtain the transmission time based on the indication from a database for storing the relationship between signals and transmission times. The network forwards these position data sets to the location server.

[0227] 6. The location server has knowledge of every satellite position at every time. For example, it can obtain this information from a database that includes the position at any given time, or from a dynamic database that is a calculator and provides the position based on the requested input time instance. Typically, the satellite operator provides this database. Some websites even provide such information publicly (for example, for TB broadcast satellites). Therefore, it can obtain the position of (multiple) satellites from the absolute time. In addition, it can derive the absolute transmission time of the signal from the indication included in the location data. The location server obtains the distance from the propagation time of the signal to the corresponding position of the satellite together with the corresponding absolute TOA. Based on the obtained (multiple) satellite positions and distances, the location server can, for example, infer the position of the UE by triangulation.

[0228] 7. If the UE requests to move into RRC_CONNECTED mode, the location server knows the location of the UE. If the location of the UE makes the request meet the requirements, the network may move the UE to RRC_CONNECTED, otherwise the request may be rejected.

[0229] In some example embodiments, the UE calculates the time difference from the measured TOA and reports the measured TOA and an indication of the absolute time of one of the arrival times. In some example embodiments, the location server calculates the TDOA from the received TOA. The location server can obtain the location of the UE based on the TDOA and the positioning of the satellite, for example, by triangulation.

[0230] If the calculated time difference is from a satellite in the same orbit (or if multiple time differences of the same satellite's TDOA at different locations are used), the hyperbolic method will lead to two possible points for the UE's location. In this case, the location server can use long-term tracking of the UE to determine which of the two points is correct. Alternatively or additionally, in the case of multiple beams from the same satellite, the beam selected for transmission can be used to determine which of the two points is the true location.

[0231] In some example embodiments of the present invention, the UE location is estimated before the UE becomes RRC_CONNECTED, allowing the network to comply with regulations or policies for a specific area / location. For example, this method may potentially prevent the UE from accessing the network based on its location. Some example embodiments of the present invention (especially those in which TOA is measured at different times for a single estimate of the UE's location) are also applicable to UEs in the RRC_CONNECTED state. In this case, the UE can report the TOA, an indication of the time of transmission, and the cell id in the RRC signaling.

[0232] In the above description, TOA is measured. In some example embodiments of the present invention, the received power of the corresponding signal, rather than TOA, may be measured and reported. If the received power is reported to the location server via the network, the report includes an indication of the received power and the time when the received power was measured. The indication that the transmit time can be obtained is replaced by an indication that the transmit power can be obtained. From the attenuation of the signal (i.e., according to the ratio of received power / transmit power), the location server can calculate the distance between the satellite and the UE, and from this distance, it can calculate the propagation time (based on the speed of light). Therefore, the location server can calculate the transmit time from the time when the signal is received and the propagation time, and calculate the positioning of the satellite when the signal is transmitted from the transmit time and the satellite orbit information. If the required information (e.g., transmit power) is available at the UE, the UE can perform (multiple) calculations and provide the calculation results to the location server.

[0233] In some example embodiments of the invention, the report may include only TOA and / or TDOA. In some example embodiments of the invention, the report may include only received power. In some example embodiments of the invention, the report may include a mix of both.

[0234] Some example embodiments of the present invention are preferably applicable to LEO satellites or HAPS constellations, where a sufficient number of different satellites can be detected by the UE and the geographical area covered by the 5G NR cell provided by each satellite / HAPS is much smaller than that of GEO / MEO satellites (see Table 6).

[0235] In some example embodiments of the present invention, the measurements may be performed in a LEO satellite or a HAPS. For these example embodiments, the UE sends a known signal (e.g., SRS) at a known time / frequency position for the airborne / spaceborne platform to detect the signal. For example, only one mobile satellite (or HAPS) may measure the uplink relative arrival time, arrival angle, or round-trip time several times. If the satellite positioning varies greatly relative to the earth between several measurements, the measurements by a single satellite (or HAPS) correspond to (almost simultaneously) measurements from multiple positionings.

[0236] Figure 4 Another timing diagram according to some example embodiments of the present invention is shown. Figure 4 The timing diagram corresponds to Figure 3 The timing diagram shows that, except when the UE is in RRC_IDLE state and does not want to move into RRC_CONNECTED mode, the UE does not collect location information and / or does not report location information. Figure 4 The TAU report shown in (left) is a regular TAU report without location information. The UE collects location information only when the UE requests to move into RRC_CONNECTED mode (in Figure 4 In Figure 3 The location server may then determine whether the UE is located such that the regulations allow the UE to be moved to RRC_CONNECTED. If the location of the UE is such that the request complies with the regulations, the network may move the UE to RRC_CONNECTED, otherwise the request may be rejected. The UE may provide location information in a message rather than in a TAU report during the process of becoming RRC_CONNECTED. For example, a newly defined message may be used for this purpose.

[0237] Figure 5 A simplified example is shown of how a NTN UE uses detected and measured cells for location purposes. According to some example embodiments of the present invention, it is assumed that the network has provided UE basic configuration parameters for periodic TAU reporting and includes parameters for location measurement and reporting.

[0238] In this example, during the TAU period:

[0239] At time t0 (the first measurement period in the TAU period), the UE detects two cells and stores their identifiers (e.g., PCIs): PCI 1 (for satellite SAT11) and PCI 2 (for satellite SAT12), corresponding to TOA 11 and TOA 12, based on the time reference (SIB16 and UTC time, 16 μs accuracy) and frame / symbol time offsets broadcast by the gNB.

[0240] At time t1 (second measurement period in the TAU period), the UE detects two cells and stores their identifiers (e.g. PCI): PCI 3 (for satellite SAT13) and PCI4 (for satellite SAT21), corresponding to TOA 13 and TOA 21, based on the time reference (SIB16 and UTC time, 16μs accuracy) and frame / symbol time offset broadcast by the gNB.

[0241] This detection / measurement sequence continues until a predefined / configured stop condition (see above) is met or the TAU period expires.

[0242] When a TAU is reported:

[0243] 1) The UE also includes the stored results of the above measurements in the TAU report ("location data set", each stored result includes, for example, absolute TOA, identification of received signal, and cell ID; or received power, power measurement time, identification of received signal, and hardware cell ID)

[0244] 2) The NTN RAN (ie location server) uses the location data set to estimate the UE's position on Earth at the time the TOA value is estimated (ie within a TAU reporting period, or within a fragment of a TAU reporting period if a stopping condition applies) .

[0245] Step 2) is feasible (within certain accuracy and ambiguity margins) because:

[0246] - The speed of UEs on Earth (up to 300 m / s according to 3GPP TR 38.811 and 3GPP TR 38.821) is much smaller than the speed of LEO satellites (~7.8 km / s).

[0247] - The satellite orbits and, therefore, the satellite's position are known with high accuracy wrt any geographical location on Earth.

[0248] exist Figure 5 In the example of FIG. 1 , it is shown that the measurements may include satellites in the same orbit or in different orbits. Obviously, for the purpose of position triangulation, the best scenario is when the UE can detect at least 3 satellites (corresponding to the PCI), at least one of which moves in a different orbit compared to the other detected satellites. However, this scenario is not guaranteed to occur universally for all UE positions and / or in any satellite constellation. The design of the NTN constellation (the number of orbits and satellites) may also be based on this requirement and other coverage, capacity and orbital constraints.

[0249] In some example embodiments of the present invention, the detected cells (and corresponding cell identifiers) may be different from each other, or two or more detected cells (and corresponding cell identifiers) may be the same. Figure 5 In the following examples, for example but not limited to, PCI1 (of satellite SAT11) and PCI3 (of satellite SAT13) can be the same PCI or different PCIs. Figure 5 In the following examples, for example but not limited to, SAT11 and SAT13 may be the same satellite or different satellites. According to some example embodiments of the present invention, the same or different satellites may provide TOA values ​​(and / or other similar position measurements of parameters or position information addressed by example embodiments of the present invention) at two different times.

[0250] The network can track the UE in RRC_IDLE mode even if the UE accesses the network not via satellite but via a terrestrial base station. From the TAU report, the network knows the cells of the idle UE. However, sometimes (for example, when the UE is located in a cell at the overlapping border of two countries with different regulations for network access), more accurate location information is needed, and this location information is preferably available before the UE enters RRC_CONNECTED.

[0251] Thus, in some example embodiments of the invention, the TAU report may include location information that allows the network to determine the location more accurately than location information at the cell level. An example of such location information is the three location data sets described above. Another example of such location information is GNSS location data (if available, for example from GPS; note that there is a risk that the GNSS data may be falsified or blocked). If the gNB receives this location information in the TAU report, it forwards this location information to the location server, enabling the location server to determine the UE's location with greater accuracy than the accuracy at the cell level.

[0252] Figure 6 An apparatus according to an exemplary embodiment of the present invention is shown. The apparatus may be a terminal (eg, UE) or an element thereof. Figure 7 A method according to an exemplary embodiment of the present invention is shown. Figure 6 The device can perform Figure 7 method, but not limited to this method. Figure 7 The method can be Figure 6 The present invention is performed by a device, but is not limited to being performed by the device.

[0253] The apparatus comprises a component 10 for measuring and a component 20 for reporting. The component 10 for measuring and the component 20 for reporting may be a measuring component and a reporting component, respectively. The component 10 for measuring and the component 20 for reporting may be a measurer and a reporter, respectively. The component 10 for measuring and the component 20 for reporting may be a measurement processor and a reporting processor, respectively.

[0254] The component 10 for measuring is used to measure a first absolute arrival time of a first signal from a first satellite, a second absolute arrival time of a second signal from a second satellite, and a third absolute arrival time of a third signal from a third satellite during a reporting period (S10). The first signal, the second signal, and the third signal identify the first satellite, the second satellite, and the third satellite respectively by a first cell identifier, a second cell identifier, and a third cell identifier. The first satellite, the second satellite, and the third satellite (and the corresponding first cell identifier, the second cell identifier, and the third cell identifier) ​​may be different from each other, or two or three of the first satellite, the second satellite, and the third satellite (and the corresponding first cell identifier, the second cell identifier, and the third cell identifier) ​​may be the same. The first absolute arrival time is measured within a first measurement interval set in the reporting period. The second absolute arrival time is measured within a second measurement interval set in the reporting period. The second measurement interval does not overlap with the first measurement interval. For example, the first measurement interval and the second measurement interval may be predefined within the reporting period. As another example, assuming that the first measurement interval is earlier than the second measurement interval, the end of the first measurement interval can be determined so that it has a first predefined time lag with the measurement of the first absolute arrival time, the start of the second measurement interval can be determined so that it has a second predefined time lag with the measurement of the first absolute arrival time, and the second predefined time lag is greater than the first predefined time lag.

[0255] After the reporting period has elapsed, the reporting means 20 reports:

[0256] an indication of a first absolute time of arrival together with a first cell identifier and a first parameter allowing to derive an absolute time of transmission of the first signal,

[0257] an indication of a second absolute time of arrival together with a second cell identifier and a second parameter allowing the absolute time of transmission of the second signal to be derived, and

[0258] - An indication of a third absolute time of arrival together with a third cell identifier and a third parameter allowing the absolute sending time of the third signal to be derived.

[0259] Each of the first to third parameters may include an absolute transmission time of the corresponding signal. Each of the first to third parameters may include an identification of the corresponding signal. Therefore, depending on the identification of the signal, the location server may obtain (directly or by dynamic calculation) the absolute transmission time based on the identification and a database indicating the absolute transmission time of the corresponding signal. The component for reporting may report to the network (location server) via a fourth satellite, which may be one of the first to third satellites or may be different from each of the first to third satellites.

[0260] Figure 8 An apparatus according to an exemplary embodiment of the present invention is shown. The apparatus may be a terminal (eg, UE) or an element thereof. Fig. 9 A method according to an exemplary embodiment of the present invention is shown. Figure 6 The device can perform Fig. 9 method, but not limited to this method. Fig. 9 The method can be Figure 8 The present invention is performed by a device, but is not limited to being performed by the device.

[0261] The apparatus comprises a component for measuring 110 and a component for reporting 120. The component for measuring 110 and the component for reporting may be a measuring component and a reporting component, respectively. The component for measuring 110 and the component for reporting may be a measurer and a reporter, respectively. The component for measuring 110 and the component for reporting 120 may be a measurement processor and a reporting processor, respectively.

[0262] The component 110 for measuring measures a first received power of a first signal from a first satellite, a second received power of a second signal from a second satellite, and a third received power of a third signal from a third satellite during a reporting period (S110). The first signal, the second signal, and the third signal identify the first satellite, the second satellite, and the third satellite by a first cell identifier, a second cell identifier, and a third cell identifier, respectively. The first satellite, the second satellite, and the third satellite (and the corresponding first cell identifier, the second cell identifier, and the third cell identifier) ​​may be different from each other, or two or three of the first satellite, the second satellite, and the third satellite (and the corresponding first cell identifier, the second cell identifier, and the third cell identifier) ​​may be the same.

[0263] The first received power is measured in a first measurement interval set in the reporting period. The second received power is measured in a second measurement interval set in the reporting period. The second measurement interval does not overlap with the first measurement interval. For example, the first and second measurement intervals can be predefined in the reporting period. As another example, assuming that the first measurement interval is earlier than the second measurement interval, the end of the first measurement interval can be determined so that it has a first predefined time lag with the measurement of the first received power, and the start of the second measurement interval can be determined so that it has a second predefined time lag with the measurement of the first received power, and the second predefined time lag is greater than the first predefined time lag.

[0264] After the reporting period has elapsed, the component for reporting 120 reports:

[0265] an indication of a first received power together with a first cell identifier, when the first received power is measured

[0266] an indication of a second received power together with a second cell identifier, a second absolute time when the second received power was measured, and a first parameter allowing the transmission power of the first signal to be derived, and

[0267] • An indication of a third received power together with a third cell identifier, a third absolute time when the third received power was measured, and a third parameter allowing the transmit power of the third signal to be derived.

[0268] Each of the first to third parameters may include a transmit power of the corresponding signal. Each of the first to third parameters may include an identification of the corresponding signal. Therefore, depending on the identification of the signal, the location server may obtain (directly or by dynamic calculation) the transmit power based on the identification and a database indicating the transmit power of the corresponding signal. The component for reporting may report to the network (location server) via a fourth satellite, which may be one of the first to third satellites or may be different from each of the first to third satellites.

[0269] Fig.10 An apparatus according to an exemplary embodiment of the invention is shown. The apparatus may be a satellite or an element thereof. Fig.11 A method according to an exemplary embodiment of the present invention is shown. Fig.10 The device can perform Fig.11 method, but not limited to this method. Fig.11 The method can be Fig.10 The present invention is performed by a device, but is not limited to being performed by the device.

[0270] The apparatus includes a component 210 for measuring and a component 220 for reporting. The component 210 for measuring and the component 220 for reporting may be a measuring component and a reporting component, respectively. The component 210 for measuring and the component 220 for reporting may be a measurer and a reporter, respectively. The component 210 for measuring and the component 220 for reporting may be a measurement processor and a reporting processor, respectively.

[0271] The component 210 for measuring measures at least one of the first arrival time of the first signal from the terminal, the first arrival angle of the second signal from the terminal, and the first round trip time of the third signal from the terminal within the set first measurement interval during the set reporting period; and measures at least one of the second arrival time of the fourth signal from the terminal, the second arrival angle of the fifth signal from the terminal, and the second round trip time of the sixth signal from the terminal within the set second measurement interval during the reporting period (S210). The first measurement interval does not overlap with the second measurement interval. For example, the first measurement interval and the second measurement interval can be predefined within the reporting period. As another example, assuming that the first measurement interval is earlier than the second measurement interval, the end of the first measurement interval can be determined so that it has a first predefined time lag with the measurement performed in the first measurement interval, and the start of the second measurement interval can be determined so that it has a second predefined time lag with the measurement performed in the first measurement interval, and the second predefined time lag is greater than the first predefined time lag. Each of the first to sixth signals (if applicable) identifies the terminal by a corresponding terminal identifier (e.g., IMSI, MSISDN, etc.). Different signals may use the same terminal identifier or different terminal identifiers.

[0272] After the reporting period has elapsed, the component for reporting 220 reports:

[0273] The terminal's identification,

[0274] the identity of the satellite that contains the device,

[0275] an indication of the measured at least one of a first arrival time, a first angle of arrival, and a first round trip time together with an identification of a respective at least one of the first signal, the second signal, and the third signal, and a respective first absolute measured time when the respective at least one of the first arrival time, the first angle of arrival, and the first round trip time was measured. and

[0276] an indication of the measured at least one of a second arrival time, a second angle of arrival, and a second round trip time together with an identification of a respective at least one of the fourth, fifth, and sixth signals, and a respective second absolute measured time when the respective at least one of the second arrival time, the second angle of arrival, and the second round trip time was measured.

[0277] Fig.12 An apparatus according to an exemplary embodiment of the present invention is shown. The apparatus may be a location server or an element thereof. Fig.13 A method according to an exemplary embodiment of the present invention is shown. Fig.12 The device can perform Fig.13 method, but not limited to this method. Fig.13 The method can be Fig.12 The present invention is performed by a device, but is not limited to being performed by the device.

[0278] The apparatus includes a component 310 for obtaining and a component 320 for estimating. The component 310 for obtaining and the component 320 for estimating may be an obtaining component and an estimating component, respectively. The component 310 for obtaining and the component 320 for estimating may be an obtainer and an estimator, respectively. The component 310 for obtaining and the component 320 for estimating may be an obtaining processor and an estimating processor, respectively.

[0279] The component 310 for obtaining obtains the corresponding position of the corresponding satellite for each of the plurality of pairs of the indication of the corresponding absolute arrival time of the corresponding signal from the corresponding satellite and the corresponding satellite identity based on the information about the corresponding orbit (S310);

[0280] The component 310 for obtaining obtains the corresponding position of the corresponding satellite for each of the multiple pairs of indications of the corresponding absolute arrival time of the corresponding signal from the corresponding satellite and the corresponding satellite identity based on the information about the corresponding satellite orbit (S310). For each of the multiple pairs of the corresponding absolute arrival time and the corresponding satellite identity, the corresponding satellite is identified by the corresponding satellite identity. At least one of the absolute arrival times is different from another absolute arrival time of the absolute arrival times.

[0281] The component 320 for estimating estimates the location of the terminal based on the obtained multiple locations and the related multiple location data sets (S320). Each location data set in the multiple location data sets includes a corresponding absolute arrival time and a corresponding parameter that allows the absolute transmission time of the corresponding signal to be derived. Each parameter may include the absolute transmission time of the corresponding signal. Each parameter may include the identification of the corresponding signal. Therefore, depending on the identification of the signal, the location server can obtain the absolute transmission time (directly or by dynamic calculation) based on the identification and the database indicating the absolute transmission time of the corresponding signal.

[0282] Fig.14 An apparatus according to an exemplary embodiment of the present invention is shown. The apparatus may be a location server or an element thereof. Fig.15 A method according to an exemplary embodiment of the present invention is shown. Fig.14 The device can perform Fig.15 method, but not limited to this method. Fig.15 The method can be Fig.14 The present invention is performed by a device, but is not limited to being performed by the device.

[0283] The apparatus includes a component 410 for obtaining and a component 420 for estimating. The component 410 for obtaining and the component 420 for estimating may be an obtaining component and an estimating component, respectively. The component 410 for obtaining and the component 420 for estimating may be an obtainer and an estimator, respectively. The component 410 for obtaining and the component 420 for estimating may be an obtaining processor and an estimating processor, respectively.

[0284] The component 410 for obtaining obtains the corresponding position of the corresponding satellite for each of the multiple pairs of indications of the corresponding absolute arrival time of the corresponding signal from the corresponding satellite and the corresponding satellite identity based on the information about the corresponding satellite orbit (S410). For each of the multiple pairs of the corresponding absolute arrival time and the corresponding satellite identity, the corresponding satellite is identified by the corresponding satellite identity. At least one of the absolute arrival times is different from another absolute arrival time of the absolute arrival times.

[0285] The component 420 for estimating estimates the position of the terminal based on the obtained multiple positions and the related multiple position data sets (S420). Each position data set in the multiple position data sets includes a corresponding absolute measurement time and a corresponding parameter that allows the transmission power of the corresponding signal to be derived. Each parameter may include the transmission power of the corresponding signal. Each parameter may include the identification of the corresponding signal. Therefore, depending on the identification of the signal, the location server can obtain the transmission power (directly or by dynamic calculation) based on the identification and the database indicating the transmission power of the corresponding signal.

[0286] Fig.16 An apparatus according to an exemplary embodiment of the present invention is shown. The apparatus may be a terminal, such as a UE or an element thereof. Fig.17 A method according to an exemplary embodiment of the present invention is shown. Fig.16 The device can perform Fig.17 method, but not limited to this method. Fig.17 The method can be Fig.16 The present invention is performed by a device, but is not limited to being performed by the device.

[0287] The apparatus includes a component 510 for checking and a component 520 for providing. The component 510 for checking and the component 520 for providing may be an checking component and a providing component, respectively. The component 510 for checking and the component 520 for providing may be an inspector and a provider, respectively. The component 510 for checking and the component 520 for providing may be an inspection processor and a providing processor, respectively.

[0288] The component 510 for checking checks whether the location information for the terminal including the device is available (S510). The location information enables the location of the terminal to be determined more accurately than at the cell level. For example, the location information may include GNSS data. The location information may include a set of three indications, each indicating directly or indirectly the distance to the satellite at the corresponding absolute time.

[0289] If the location information is available (S510=Yes), the providing means 520 provides the location information together with the tracking area update report of the terminal to the network (S520).

[0290] Fig.18 An apparatus according to an example embodiment of the present invention is shown. The apparatus may be a base station (such as a gNB or eNB or an element thereof) or a base station controller. Fig.19 A method according to an exemplary embodiment of the present invention is shown. Fig.18 The device can perform Fig.19 method, but not limited to this method. Fig.19 The method can be Fig.18 The present invention is performed by a device, but is not limited to being performed by the device.

[0291] The apparatus includes a component 610 for checking and a component 620 for forwarding. The component 610 for checking and the component 620 for forwarding may be a checking component and a forwarding component, respectively. The component 610 for checking and the component 620 for forwarding may be a checker and a forwarder, respectively. The component 610 for checking and the component 620 for forwarding may be a checking processor and a forwarding processor, respectively.

[0292] The checking device 610 checks whether the tracking area update report received from the terminal includes location information (S610). The location information enables the location of the terminal to be determined more accurately than at the cell level. For example, the location information may include GNSS data. The location information may include three indication sets, each of which directly or indirectly indicates the distance to the satellite at the corresponding absolute time.

[0293] If the location information is available (S610=Yes), the means for forwarding 620 forwards the location information to the location server (S620).

[0294] Fig. 20 An apparatus according to an example embodiment of the present invention is shown. The apparatus comprises at least one processor 810, at least one memory 820 comprising computer program code, and the at least one processor 810 together with the at least one memory 820 and the computer program code are arranged to cause the apparatus to at least perform a process according to Figure 7 , Fig. 9 , Fig.11 , Fig.13 , Fig.15 , Fig.17 and Fig.19 And at least one of the methods described in the related description.

[0295] In some of the example embodiments described above, the UE measures TOA at several occasions during the TAU reporting period until at least one of certain stop conditions (number of measurements, etc.) is met, and then it reports the measured TOA together with the relevant cell identifier and an indication enabling the transmission time to be obtained. In some example embodiments of the present invention, the UE may measure TOA periodically (or based on events) independently of the TAU reporting period. At the end of the TAU reporting period, the latest measurement result is reported.

[0296] To adapt the accuracy of the UE's position estimate, the location server may consider measurements from different periods than the entire set of position data obtained in a certain TAU reporting period. For example, it may consider only a subset of measurements within a TAU period (subsequent or non-subsequent) to improve accuracy if the UE is moving quickly, or reduce accuracy if the UE is stationary, or it may consider measurements from two or more subsequent TAU ​​reporting periods to reduce accuracy if the UE is moving quickly, or improve accuracy if the UE is stationary. The UE may be configured with different TAU ​​reporting periods for the same purpose.

[0297] In the above, some example embodiments are described in which the UE is in RRC_IDLE mode when it measures TOA and / or received power from (multiple) satellites. However, the present invention is not limited to UEs in RRC_IDLE mode. For example, in some example embodiments of the present invention, when the UE is in RRC_CONNECTED mode, the UE may perform measurements of TOA and / or received power from (multiple) satellites. In this case, the UE may report the corresponding location information to the location server in the same manner as other location information (such as GPS measurements).

[0298] If the UE is in RRC_IDLE mode, in some exemplary embodiments of the present invention, the UE may report location information in a message different from the TAU report. Such information will be defined in a new way.

[0299] The term "A is reported together with B" means that the receiver of the report understands that A and B are associated with each other. The report can indicate this association in a variety of ways. For example, A and B can be reported as a data pair in a single information element, or some metadata can indicate that A and B are associated with each other.

[0300] Absolute time can be indicated in a variety of ways. For example, it can be indicated in seconds from a defined starting point or as a system frame number (SFN). Correspondingly, relative time can be indicated in a variety of ways, such as as seconds or as a system frame number. The indication of absolute time can correspond to the indication of relative time, or it can be different from it.

[0301] Some example embodiments of the present invention are described based on 3GPP networks (e.g., NR). However, the present invention is not limited to NR. It can be applied to 3GPP networks of any generation (3G, 4G, 5G, etc.). However, the present invention is not limited to 3GPP networks. It can also be applied to other radio networks that provide communications via satellite links.

[0302] UE is an example of a terminal. However, the terminal (UE) may be any device capable of connecting to a (3GPP) radio network via a channel, such as an MTC device, an IoT device, etc.

[0303] The definitions indicated in this specification are based on the current 3GPP standards. However, they do not limit the present invention. Other definitions based on the same or corresponding concepts are also applicable to some exemplary embodiments of the present invention.

[0304] A piece of information can be sent from one entity to another entity via one or more messages. Each of these messages can contain other (different) information.

[0305] The names of network elements, protocols and methods are based on current standards. In other versions or other technologies, the names of these network elements and / or protocols and / or methods may be different, as long as they provide corresponding functions.

[0306] If not otherwise clarified or otherwise clear from the context, different interpretations of two entities mean that they perform different functions. This does not necessarily mean that they are based on different hardware. That is, each entity described in this specification may be based on different hardware, or some or all entities may be based on the same hardware. This does not necessarily mean that they are based on different software. That is, each entity described in this specification may be based on different software, or some or all entities may be based on the same software. Each entity described in this specification may be implemented in the cloud.

[0307] From the above description, it should be apparent that the exemplary embodiments of the present invention provide, for example, a terminal (such as a UE) or a component thereof, an apparatus implementing the terminal, a method for controlling and / or operating the terminal, (multiple) computer programs for controlling and / or operating the terminal, and a medium carrying such (multiple) computer programs and forming (multiple) computer program products. From the above description, it should be apparent that the exemplary embodiments of the present invention provide, for example, a satellite acting as a base station (e.g., a gNB or an eNB) or a component thereof, an apparatus implementing a satellite acting as a base station, a method for controlling and / or operating a satellite acting as a base station, (multiple) computer programs for controlling and / or operating a satellite acting as a base station, and a medium carrying such (multiple) computer programs and forming (multiple) computer program products. From the above description, it should be apparent that the exemplary embodiments of the present invention provide, for example, a location server (e.g., an E-SMLC, an SMLC, or an SLP) or a component thereof, an apparatus implementing a location server, a method for controlling and / or operating a location server, (multiple) computer programs for controlling and / or operating a location server, and a medium carrying such (multiple) computer programs and forming (multiple) computer program products.

[0308] Implementation of any of the above blocks, apparatus, systems, techniques or methods includes, as non-limiting examples, implementation as hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing device, or some combination thereof.

[0309] It should be understood that the above are currently considered to be preferred exemplary embodiments of the present invention. However, it should be noted that the description of the preferred exemplary embodiments is given by way of example only and that various modifications may be made without departing from the scope of the present invention as defined by the appended claims.

[0310] The foregoing description has provided by way of non-limiting examples a complete and informative description of the exemplary embodiments. However, various modifications and adaptations may become apparent to those skilled in the relevant art in view of the foregoing description when read in conjunction with the accompanying drawings and the appended claims. However, all such modifications and similar modifications to the teachings of the present invention will still fall within the scope of the present invention as defined by the appended claims. Indeed, there are further embodiments comprising combinations of one or more embodiments with any of the foregoing embodiments.

Claims

1. A device for communication, comprising: at least one processor and at least one memory, the at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processor, cause the apparatus to at least: measuring, during a reporting period, a first absolute time of arrival of a first signal from a first satellite identified by a first cell identifier, a second absolute time of arrival of a second signal from a second satellite identified by a second cell identifier, and a third absolute time of arrival of a third signal from a third satellite identified by a third cell identifier; after the reporting period has elapsed, reporting an indication of the first absolute time of arrival together with the first cell identifier and a first parameter enabling derivation of an absolute time of transmission of the first signal, reporting an indication of the second absolute time of arrival together with the second cell identifier and a second parameter enabling derivation of an absolute time of transmission of the second signal, and reporting an indication of the third absolute time of arrival together with the third cell identifier and a third parameter enabling derivation of an absolute time of transmission of the third signal, wherein The at least one processor and the computer program code are configured to cause the apparatus to measure comprises: the at least one processor and the computer program code are configured to cause the apparatus to: measuring the first absolute arrival time within a first measurement interval set in the reporting period; The second absolute arrival time is measured in a second measurement interval set in the reporting period; the second measurement interval does not overlap with the first measurement interval.

2. The device according to claim 1, wherein The first satellite is the same as the second satellite, and The time difference between the second absolute arrival time and the first absolute arrival time is greater than a set minimum time period.

3. The apparatus according to any one of claims 1 to 2, wherein a terminal including the apparatus is in idle mode, and the at least one processor and computer program code are configured to cause the apparatus report to include: The at least one processor and the computer program code are configured to cause the apparatus to report to a fourth satellite at a tracking area update of the terminal.

4. The apparatus according to any one of claims 1 to 2, wherein a terminal including the apparatus is in idle mode, and the at least one processor and computer program code are configured to cause the apparatus report to include: The at least one processor and the computer program code are configured to cause the apparatus to report to a network at a tracking area update of the terminal.

5. The apparatus of any one of claims 1 to 2, wherein the at least one processor and computer program code are configured to cause the apparatus report to include: The at least one processor and the computer program code are configured to cause the apparatus to report regardless of whether a terminal including the apparatus is connected to any of the first satellite, the second satellite, and the third satellite.

6. The device according to any one of claims 1 to 2, wherein: The at least one processor and the computer program code are configured to further cause the apparatus to: checking whether a stop condition is satisfied during the reporting period; After the stop condition is satisfied during the reporting period, the apparatus is prohibited from measuring any of the first absolute arrival time, the second absolute arrival time, or the third absolute arrival time during the reporting period.

7. The device according to any one of claims 1 to 2, wherein: The at least one processor and the computer program code are configured to further cause the apparatus to: calculating an arrival time difference between the first absolute arrival time and the second absolute arrival time, and An indication of the arrival time difference is reported as the indication of the second absolute arrival time.

8. The apparatus of any one of claims 1 to 2, wherein the at least one processor and the computer program code are configured to cause the apparatus to: measuring at least one of the first absolute arrival time, the second absolute arrival time, and the third absolute arrival time as a respective time difference relative to an absolute time; and The respective time difference and the absolute time are reported as a respective one of the at least one of the first absolute arrival time, the second absolute arrival time, and the third absolute arrival time.

9. The apparatus according to any one of claims 1 to 2, wherein at least one of the first parameter, the second parameter and the third parameter is the respective absolute transmission time, and the at least one processor and the computer program code are configured to cause the apparatus to: The corresponding absolute transmission time is acquired from a corresponding one of the first signal, the second signal and the third signal.

10. An apparatus for communication, comprising: at least one processor and at least one memory, the at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processor, cause the apparatus to at least: measuring during a reporting period a first received power of a first signal from a first satellite identified by a first cell identifier, a second received power of a second signal from a second satellite identified by a second cell identifier, and a third received power of a third signal from a third satellite identified by a third cell identifier; after the reporting period has elapsed, reporting an indication of the first received power together with the first cell identifier, a first absolute time when the first received power was measured, and a first parameter enabling the absolute transmission time of the first signal to be derived, reporting an indication of the second received power together with the second cell identifier, a second absolute time when the second received power was measured, and a second parameter enabling the absolute transmission time of the second signal to be derived, and reporting an indication of the third received power together with the third cell identifier, a third absolute time when the third received power was measured, and a third parameter enabling the absolute transmission time of the third signal to be derived, wherein The at least one processor and the computer program code are configured to cause the apparatus to measure comprises: the at least one processor and the computer program code are configured to cause the apparatus to: measuring the first received power within a first measurement interval set in the reporting period; and measuring the second received power within a second measurement interval set in the reporting period; and The second measurement interval differs from the first measurement interval by a minimum time interval.

11. The device according to claim 10, wherein The first satellite is identical to the second satellite.

12. The apparatus according to any one of claims 10 to 11, wherein a terminal including the apparatus is in idle mode, and the at least one processor and computer program code are configured to cause the apparatus report to include: The at least one processor and the computer program code are configured to cause the apparatus to report to a fourth satellite at a tracking area update of the terminal.

13. The apparatus according to any one of claims 10 to 11, wherein a terminal including the apparatus is in idle mode, and the at least one processor and computer program code are configured to cause the apparatus report to include: The at least one processor and the computer program code are configured to cause the apparatus to report to a network at a tracking area update of the terminal.

14. The apparatus of any one of claims 10 to 11, wherein the at least one processor and computer program code are configured to cause the apparatus report to include: The at least one processor and the computer program code are configured to cause the apparatus to report regardless of whether a terminal including the apparatus is connected to any of the first satellite, the second satellite, and the third satellite.

15. The device according to any one of claims 10 to 11, wherein: The at least one processor and the computer program code are configured to further cause the apparatus to: checking whether a stop condition is satisfied during the reporting period; and After the stop condition is met in the reporting period, the apparatus is prohibited from measuring any received power in the reporting period.

16. An apparatus for communication, comprising: at least one processor and at least one memory, the at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processor, cause the apparatus to at least: measuring, within a set first measurement interval during a set reporting period, at least one of a first arrival time of a first signal from a terminal, a first arrival angle of a second signal from the terminal, and a first round trip time of a third signal from the terminal, and being configured to measure, within a set second measurement interval during the reporting period, at least one of a second arrival time of a fourth signal from the terminal, a second arrival angle of a fifth signal from the terminal, and a second round trip time of a sixth signal from the terminal; reporting, after the reporting period has elapsed, an identification of the terminal, including an identification of a satellite of the apparatus, an indication of the measured at least one of the first time of arrival, the first angle of arrival, and the first round trip time together with the first signal, an identification of a respective at least one of the second signal and the third signal and a respective first absolute measurement time at which a respective at least one of the first time of arrival, the first angle of arrival, and the first round trip time was measured, and an indication of the measured at least one of the second time of arrival, the second angle of arrival, and the second round trip time together with an identification of a respective at least one of the fourth signal, the fifth signal, and the sixth signal and a respective second absolute measurement time at which a respective at least one of the second time of arrival, the second angle of arrival, and the second round trip time was measured, wherein The first measurement interval does not overlap with the second measurement interval.

17. The apparatus of claim 16, wherein at least one of the following pairs of conditions applies: if the apparatus is configured to measure the first arrival time, the apparatus is configured to measure the second arrival time, and if the apparatus is configured to measure the second arrival time, the apparatus is configured to measure the first arrival time; if the apparatus is configured to measure the first angle of arrival, the apparatus is configured to measure the second angle of arrival, and if the apparatus is configured to measure the second angle of arrival, the apparatus is configured to measure the first angle of arrival; as well as If the apparatus is configured to measure the first round trip time, the apparatus is configured to measure the second round trip time, and if the apparatus is configured to measure the second round trip time, the apparatus is configured to measure the first round trip time.

18. A method for communication, comprising: measuring, during a reporting period, a first absolute time of arrival of a first signal from a first satellite identified by a first cell identifier, a second absolute time of arrival of a second signal from a second satellite identified by a second cell identifier, and a third absolute time of arrival of a third signal from a third satellite identified by a third cell identifier; after the reporting period has elapsed, reporting an indication of the first absolute time of arrival together with the first cell identifier and a first parameter enabling derivation of an absolute time of transmission of the first signal, reporting an indication of the second absolute time of arrival together with the second cell identifier and a second parameter enabling derivation of an absolute time of transmission of the second signal, and reporting an indication of the third absolute time of arrival together with the third cell identifier and a third parameter enabling derivation of an absolute time of transmission of the third signal, wherein The first absolute arrival time is measured within a first measurement interval set in the reporting period; The second absolute arrival time is measured within a second measurement interval set in the reporting period; The second measurement interval does not overlap with the first measurement interval.

19. The method according to claim 18, wherein The first satellite is the same as the second satellite, and The time difference between the second absolute arrival time and the first absolute arrival time is greater than a set minimum time period.

20. The method according to any one of claims 18 to 19, wherein a terminal comprising means for performing the method is in idle mode and the reporting is made to a fourth satellite at a tracking area update of the terminal.

21. The method according to any one of claims 18 to 19, wherein a terminal comprising means for performing the method is in idle mode and the reporting is made to the network at a tracking area update of the terminal.

22. The method according to any one of claims 18 to 19, wherein the reporting is performed regardless of whether a terminal comprising means for performing the method is connected to any one of the first satellite, the second satellite and the third satellite.

23. The method according to any one of claims 18 to 19, further comprising: checking whether a stop condition is satisfied during the reporting period; After the stop condition is satisfied in the reporting period, measurement of any of the first absolute arrival time, the second absolute arrival time, or the third absolute arrival time is prohibited in the reporting period.

24. The method according to any one of claims 18 to 19, further comprising: The calculation is configured to calculate the arrival time difference between the first absolute arrival time and the second absolute arrival time, and wherein The indication of the arrival time difference is reported as the indication of the second absolute arrival time.

25. The method according to any one of claims 18 to 19, wherein At least one of the first absolute arrival time, the second absolute arrival time, and the third absolute arrival time is measured as a respective time difference relative to an absolute time; and The respective time difference and the absolute time are reported as a respective one of the at least one of the first absolute arrival time, the second absolute arrival time, and the third absolute arrival time.

26. The method according to any one of claims 18 to 19, wherein at least one of the first parameter, the second parameter and the third parameter is the corresponding absolute sending time, and the method further comprises: The corresponding absolute transmission time is obtained from a corresponding one of the first signal, the second signal and the third signal.

27. A method for communication, comprising: measuring, during a reporting period, a first received power of a first signal from a first satellite identified by a first cell identifier, a second received power of a second signal from a second satellite identified by a second cell identifier, and a third received power of a third signal from a third satellite identified by a third cell identifier; after the reporting period has elapsed, reporting an indication of the first received power together with the first cell identifier, a first absolute time when the first received power was measured, and a first parameter enabling the absolute transmission time of the first signal to be derived, reporting an indication of the second received power together with the second cell identifier, a second absolute time when the second received power was measured, and a second parameter enabling the absolute transmission time of the second signal to be derived, and reporting an indication of the third received power together with the third cell identifier, a third absolute time when the third received power was measured, and a third parameter enabling the absolute transmission time of the third signal to be derived, wherein The first received power is measured within a first measurement interval set in the reporting period; The second received power is measured within a second measurement interval set in the reporting period; The second measurement interval differs from the first measurement interval by a minimum time interval.

28. The method of claim 27, wherein The first satellite is identical to the second satellite.

29. The method according to any one of claims 27 to 28, wherein the terminal comprising means for performing the method is in idle mode and the reporting is made to a fourth satellite at a tracking area update of the terminal.

30. The method according to any one of claims 27 to 28, wherein a terminal comprising means for performing the method is in idle mode and the reporting is made to the network at a tracking area update of the terminal.

31. The method according to any one of claims 27 to 28, wherein the reporting is performed regardless of whether a terminal comprising means for performing the method is connected to any one of the first satellite, the second satellite and the third satellite.

32. The method according to any one of claims 27 to 28, further comprising: checking whether a stop condition is satisfied during the reporting period; After the stop condition is met in the reporting period, any measurement of received power in the reporting period is prohibited.

33. A method for communication, comprising: measuring, within a set first measurement interval during a set reporting period, at least one of a first arrival time of a first signal from a terminal, a first arrival angle of a second signal from the terminal, and a first round trip time of a third signal from the terminal; and measuring, within a set second measurement interval during the reporting period, at least one of a second arrival time of a fourth signal from the terminal, a second arrival angle of a fifth signal from the terminal, and a second round trip time of a sixth signal from the terminal; reporting, after the reporting period has elapsed, an identification of the terminal, including an identification of a satellite of an apparatus performing the method, an indication of the measured at least one of the first time of arrival, the first angle of arrival and the first round trip time together with an identification of a corresponding at least one of the first signal, the second signal and the third signal and a corresponding first absolute measurement time when the corresponding at least one of the first time of arrival, the first angle of arrival and the first round trip time was measured, and an indication of the measured at least one of the second time of arrival, the second angle of arrival and the second round trip time together with an identification of a corresponding at least one of the fourth signal, the fifth signal and the sixth signal and a corresponding second absolute measurement time when the corresponding at least one of the second time of arrival, the second angle of arrival and the second round trip time was measured, wherein The first measurement interval does not overlap with the second measurement interval.

34. The method of claim 33, wherein at least one of the following pairs of conditions is used: If the first arrival time is measured, then the second arrival time is measured, and if the second arrival time is measured, then the first arrival time is measured; the first angle of arrival is measured, then the second angle of arrival is measured, and if the second angle of arrival is measured, then the first angle of arrival is measured; If the first round trip time is measured, then the second round trip time is measured; if the second round trip time is measured, then the first round trip time is measured.

35. A computer program product comprising a set of instructions which, when executed on an apparatus, are configured to cause the apparatus to perform a method according to any one of claims 18 to 34.

36. Computer program product according to claim 35, which is embodied as a computer readable medium or directly loadable into a computer.

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