SIDELINK POSITIONING

TECHNICAL FIELD

The present disclosure generally relates to the field of localization with regard to next generation wireless networks and its applications includes but not limited to vehicle-to- everything, V2X, public safety services, as well as commercial use cases like industry verticals or eHealth systems.

BACKGROUND

Localization has been identified as one of the potential enabling technologies of the next generation wireless networks. Current Location Service, LCS, are, e.g., provided in Long Term Evolution, LTE, and New Radio, NR, radio access technology, RAT. For such current LCS, dependent positioning techniques are applied only to downlink, DL, and/or uplink, UL, transmissions between a user equipment, UE, and base station(s), BSs, or transmission and reception points, TPRs, as shown in FIG. 1.

In more detail, FIG. 1 illustrates exemplary downlink and uplink positioning methods in LTE and 5G-NR, where DL denotes downlink; UL denotes uplink; PRS denotes positioning reference signal; DL-AOD: denotes downlink angle-of-departure; and RTT denotes round-trip- delay. This presents a performance limit to meet stringent positioning requirement in view of limited network coverage and density of BSs/TPR.

Recently, LCS applied to cases of using a user equipment, UE, in partial coverage and out-of- coverage scenarios have raised enormous attention in 3GPP discussions, especially for vehicle-to-everything, V2X, public safety services, as well as commercial use cases like industry verticals or eHealth systems. As a consequence, UE’s positioning has been performed using sidelink measurements for these RAT-dependent sidelink positioning methods, where a sidelink scenario is exploited for the transmission/reception of reference signals between users or devices without traversing any network node.

LTE and/or 5G-NR RAT-dependent positioning methods, include certain positioning methods, e.g., fordownlinktime difference of arrival, DL-TDOA, or downlink angle-of-departure, DL-AOD, which can be performed in both UE-assisted and UE-based modes. Thus, an operation in which measurements are provided by the UE to a Location Management Function, LMF, to be used in the computation of a position estimate is described as "UE-assisted", and could also be called "LMF-based", while one in which the UE computes its own position is described as "UE-based". “UE-based” and “UE-assisted” modes have different procedures on measurement and report: wherein measurements, and/or quality of positioning reference signal, PRS, is reported for UE-assisted positioning, but for UE-based positioning only location estimate is reported. Therefore, for UE-assisted positioning, a transmitter or a network obtains knowledge on the status, trend, or distributions of position link quality to a target UE given the UE’s timely report of measurements and respective quality, which are beneficial for the optimization of positioning procedures of PRS transmission.

However, available resources for PRS transmissions and positioning control signaling are often limited and/ or competitive due to scarce radio resources in out of/partial coverage scenarios. Moreover, problems with overhead, resource consumption, and/or latency are often severe for out-of coverage scenarios.

In view of the above, the present disclosure provides for monitoring of positioning link quality for agile optimization of PRS and positioning procedures in dynamic environment, by considering realistic system constraints, e.g. resource consumption, limited network coverage.

SUMMARY

The present invention provides:

A first aspect of a method of providing a measurement report of positioning link quality, comprising: obtaining, by a user equipment, UE, a triggering condition for reporting a measurement of positioning link quality; determining, by the UE, to report the measurement of positioning link quality based on the triggering condition; indicating and/or transmitting, by the UE, the measurement report to a reception entity.

Introducing a conditional triggering measurement report brings at least four-fold benefits. Firstly, a location service continuity is improved in dynamic scenarios for PosRXUE-based positioning, thus the mobility robustness of location service is also enhanced. Secondly, latency performance of positioning procedures is improved with reduced feedback resources compared to UE-assisted positioning. Thirdly, by applying two-stage measurement report with on-demand delivery of second stage report, feedback/report resource may be further reduced compared to one-stage report. Last but not the least, the proposed mechanism supports location service either in partial and/or out-of-coverage scenarios. In one possible implementation form of the method according to the previous aspect as such, the triggering condition may comprise: a quality parameter of one or more PRS resources is equal and/or smaller than a predefined threshold T1 for consecutive N1 measurement instances or time duration; or a variation of a quality parameter of one or more PRS resources is equal and/or larger than a predefined threshold T2 for consecutive N2 measurement instances or time duration.

In a possible implementation form of the method according to the previous implementation form of the previous aspect, the quality parameter may be one of receive signal quality, and positioning measurement quality.

In a possible implementation form of the method according to any preceding implementation form of the previous aspect or the previous aspect as such, indicating and transmitting the measurement report may comprise: sending, by the UE, a measurement report to a transmitting UE in a RRC or MAC CE signaling; or sending, by the UE, a measurement report to a location server, LS, in a LPP, RRC, MAC CE, or uplink control information.

In a possible implementation form of the method according to any preceding implementation form of the previous aspect or the previous aspect as such, the measurement report may comprise at least one of: a trigger indicator which indicates whether a configured triggering condition is met; a condition index of which triggering condition is met; a reporting completion indicator which indicates whether reporting is completed or whether a further measurement report follows; and a measurement result corresponding to the triggering condition.

In a possible implementation form of the method according to the previous implementation form of the previous aspect, the method may further comprise: receiving, by the UE, a scheduled resource for further measurement report transmission when the reporting completion indicator is included in the measurement report.

In a possible implementation form of the method according to the previous implementation form of the previous aspect, the method may further comprise: sending, by the UE, a second part of measurement report using the scheduled resource. In a possible implementation form of the method according to the previous implementation form of the previous aspect, the second part of measurement report may comprise the reporting completion indicator.

In a possible implementation form of the method according to any preceding implementation form of the previous aspect or the previous aspect as such, the method may further comprise: receiving, a measurement report from a second UE, wherein the measurement report comprises at least one of: a trigger indicator which indicates whether a configured triggering condition is met; a condition index of which triggering condition is met; a reporting completion indicator which indicates whether reporting is completed or whether a further measurement report follows; and a measurement result corresponding to the triggering condition.

In a possible implementation form of the method according to the previous implementation form of the previous aspect, the method may further comprise: transmitting a scheduling resource for further measurement report transmission when the reporting completion indicator is included in the measurement report.

The present invention also provides:

A second aspect of a user equipment, UE, providing a measurement report of positioning link quality, wherein the UE is configured to: obtain a triggering condition for reporting a measurement of positioning link quality; determine to report the measurement of positioning link quality based on the triggering condition; and indicate and/or transmit the measurement report to a reception entity.

In one possible implementation form of the UE according to the previous aspect as such, the triggering condition may further comprise: a quality parameter of one or more PRS resources is equal and/or smaller than a predefined threshold T1 for consecutive N1 measurement instances or time duration; or a variation of a quality parameter of one or more PRS resources is equal and/or larger than a predefined threshold T2 for consecutive N2 measurement instances or time duration. In a possible implementation form of the UE according to the previous implementation form of the previous aspect, the quality parameter may be one of receive signal quality, and positioning measurement quality.

In a possible implementation form of the method according to the previous implementation form of the previous aspect, wherein the UE being configured to indicate and/or transmit the measurement report may further comprise the UE being configured to: send a measurement report to a transmitting UE in a RRC or MAC CE signaling; or send a measurement report to a location server, LS, in a LPP, RRC, MAC CE, or uplink control information.

In a possible implementation form of the UE according to any preceding implementation form of the previous aspect or the previous aspect as such, wherein the measurement report may further comprise at least one of: a trigger indicator which indicates whether a configured triggering condition is met; a condition index of which triggering condition is met; a reporting completion indicator which indicates whether reporting is completed or whether a further measurement report follows; and a measurement result corresponding to the triggering condition.

In a possible implementation form of the UE according to the preceding implementation form of the previous aspect , wherein the UE may be further configured to: receive a scheduled resource for further measurement report transmission when the reporting completion indicator is included in the measurement report.

In a possible implementation form of the UE according to the preceding implementation form of the previous aspect, wherein the UE may be further configured to: send a second part of measurement report using the scheduled resource.

In a possible implementation form of the UE according to the preceding implementation form of the previous aspect, wherein the second part of measurement report may comprise the reporting completion indicator.

In a possible implementation form of the UE according to any preceding implementation form of the previous aspect or the previous aspect as such, wherein the UE may be further configured to: receive, a measurement report from a second UE, wherein the measurement report comprises at least one of: a trigger indicator which indicates whether a configured triggering condition is met; a condition index of which triggering condition is met; a reporting completion indicator which indicates whether reporting is completed or whether a further measurement report follows; and a measurement result corresponding to the triggering condition.

In a possible implementation form of the UE according to the preceding implementation form of the previous aspect, wherein the UE may be further configured to: transmit a scheduling resource for further measurement report transmission when the reporting completion indicator is included in the measurement report.

The present invention also provides a third aspect of a location server, LS, wherein the LS is adapted to: configure a triggering condition for reporting a measurement of positioning link quality; receive a measurement report from a user equipment, UE; wherein the triggering condition comprises: a quality parameter of one or more PRS resources is equal and/or smaller than a predefined threshold T1 for consecutive N1 measurement instances or time duration; or a variation of a quality parameter of one or more PRS resources is equal and/or larger than a predefined threshold T2 for consecutive N2 measurement instances or time duration.

In a possible implementation form of the LS according to the preceding implementation form of the previous aspect, wherein the quality parameter may be one of receive signal quality, and positioning measurement quality.

In a possible implementation form of the LS according to any preceding implementation form of the previous aspect or the previous aspect as such, the measurement report may comprise at least one of: a trigger indicator which indicates whether a configured triggering condition is met; a condition index of which triggering condition is met; a reporting completion indicator which indicates whether reporting is completed or whether a further measurement report follows; and a measurement result corresponding to the triggering condition. The present invention also provides a fourth aspect of a computer program comprising program code for performing the method as described above.

Details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description, drawings, and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following embodiments of the invention are described in more detail with reference to the attached figures and drawings, in which:

FIG. 1 illustrates exemplary downlink and uplink positioning methods in LTE and 5G-NR; FIG. 2 illustrates an example for sidelink positioning scenarios;

FIG. 3 illustrates the main procedure of the conditionally report mechanism according to an embodiment of the present disclosure;

FIG. 4 illustrates an exemplary sequence of signaling operations for a deferred activation of triggering condition according to an embodiment of the present disclosure;

FIG. 5 illustrates in the left-hand side sub-figure an example for an absolute triggering condition for a measurement report according to an embodiment of the present disclosure and illustrates in the right-hand side sub-figure an example for comparative condition(s) for a measurement report according to an embodiment of the present disclosure;

FIG. 6 illustrates a general signaling procedure of a one-stage measurement report according to an embodiment of the present disclosure;

FIG. 7 illustrates a general signaling procedure for a two-stage measurement report according to an embodiment of the present disclosure;

FIG. 8 illustrates an exemplary scenario for conditionally report inside network coverage according to an embodiment of the present disclosure;

FIG. 9 illustrates signaling procedures of a conditional report using a trigger for an in coverage scenario according to an embodiment of the present disclosure;

FIG. 10 illustrates an exemplary scenario for conditionally report an outside network coverage according to an embodiment of the present disclosure;

FIG. 11 illustrates signaling procedures of a conditional report using a trigger for an out-of- coverage scenario according to an embodiment of the present disclosure;

FIG. 12 illustrates a possible structure of a UE provided according to the embodiments of the present disclosure; FIG. 13 illustrates a possible structure of a location server provided according to the embodiments of the present disclosure;

FIG. 14 is a simplified schematic diagram of another possible design structure of a UE in the foregoing embodiments.

DETAILED DESCRIPTION OF THE EMBODIMENTS

FIG. 2 illustrates sidelink positioning scenarios. The car “Car 1”, including positioning TXUE, moves from T1 to T2, see arrow A1, and the car “Car 2”, including positioning RXUE, PosRXUE, receives PRS from the positioning TXUE, as indicated by arrow A2.

Hence, UE-based positioning may include positioning TXUE, denoted PosTXUE, positioning RXUE, denoted PosRXUE, or Master UE, denoted MasterUE, positions. UE-based positioning may be desirable for sidelink positioning, cf. FIG. 2, for various reasons, for example stringent latency requirement. In contrast to UE-assisted positioning, UE-based positioning is subject to insufficient knowledge of positioning link quality at the transmitter or network side, thus posing great challenges on maintaining the positioning service continuity with satisfactory accuracy and low latency. Such challenges are extremely dominating for sidelink positioning. On one hand, UE-based positioning poses stringent requirements such as low-latency, high precision and low power consumption target in a high-mobility scenario. Still on the other hand, limited or competitive resources for PRS transmissions and positioning control signaling need to be considered due to scarce radio resources in out of/partial coverage scenarios.

Considering PosRXUE-based, i.e. UE-based positioning for sidelink positioning, PosTXUE would be agnostic of positioning link quality due to lack of report or assistance from PosRXUE. In general, a device or program is said to be agnostic or data agnostic if the method or format of data transmission is irrelevant to the device or program’s function. This results in challenges to optimize PRS transmission and/or positioning procedures in dynamic environment. Similar observation applies to UE-based positioning for DL/UL positioning.

State of the art solutions provided by current cellular systems do not provide measurement reports for UE-based positioning apart from delivering a location estimate. By applying this state of the art solution to sidelink, SL, positioning, a PosTXUE does not obtain information regarding the quality of positioning link. As a consequence, the optimization of PRS and position procedures may not be performed or may only be performed in an agnostic manner. Deterioration of positioning service continuity and accuracy may thus be anticipated since the PosTXUE is not aware of the positioning link quality distribution or degradation during the measuring procedure. As an alternative approach, a measurement-reporting mechanism applied to UE-assisted positioning may be directly used for PosRXUE-based DL/UL/SL positioning, where such report may be pre-configured by another UE/network or may be provided in an unsolicited manner. Since the current standard only supports a mechanism that the target UE can be configured to report measurements as part of UE-assisted positioning or location estimate for UE-based positioning but not both, a new location type has been proposed by enabling the target UE to provide both the location estimate and measurement in UE-based positioning. However, large signaling overhead and large amount of RXUE feedback resources may be required, since the main feature of this approach is to report every measurement and/or the corresponding qualities. This overhead and resource consumption is extremely challenging for SL positioning in out-of-coverage use cases where UEs need to share limited SL resources without network coordination.

Reusing existing reference signals, RSs, may also be beneficial for monitoring the positioning link quality. For example, RSs such as synchronization signal block, SSB, or channel state information reference signal, CSI-RS, from DL/UL transmissions, or SL-SSB/SL-CSI-RS for SL transmission, can be utilized. However, measurements on existing RSs may not correctly indicate positioning performance due to the fact that existing RSs configuration is tailored for communication but not for positioning, e.g., not enough bandwidth for positioning, RSs are only sent together upon data transmission and/or with activation of CSI report, measurement configurations for such RSs are not adequate for positioning such as providing no path or LOS/NLOS information. Moreover, a report of RSs may not be activated at the time when positioning is needed, e.g., a report on RSs is only for RX beamforming tuning, or only upon triggering SL-CSI-RS report, which may lead to large latency for positioning.

In order to monitor positioning link quality by taking into consideration realistic system constraints such as resource consumption or limited network coverage, the present disclosure proposes a conditional report mechanism for UE-based positioning, FIG. 3, which includes two main parts:

Part 1 : Configuration of triggering for measurement report: In FIG. 3, step 1 is the configuration of trigger, measurement and report to PosRXUE/PosTXUE, and step 2 is the implementation of a trigger either at PosTXUE or at PosRXUE.

Part 2: Indication and transmission of measurement report: In FIG. 3, step 3 corresponds to report procedures. FIG. 3 illustrates the main procedure of the conditionally report mechanism. In the following, detailed descriptions of these two parts are provided. Triggering for measurement report:

Two triggering options are provided to initiate a measurement report for UE-based positioning. First, a measurement report may be triggered by an external client, which may involve applications, sensor information or map information. Such trigger may be applied at either transmitter or receiver side, e.g., PosTXUE or PosRXUE, and its application is using UE’s or network’s implementation. Second, a measurement report may be triggered by radio-based measurements on RSs. In such circumstance, the triggering conditions need to be clearly provided to the RXUE by, pre-configuration. Hence, in the following, details of triggering condition will be described.

Activation of triggering condition:

The Triggering condition may be activated in two manners. The first manner is to activate the evaluation of the triggering condition immediately once condition has been configured.

The second manner includes deferred activation of the triggering condition. Namely, the evaluation of the triggering condition is only started at the point in time when a certain additional condition, but not the triggering condition, is fulfilled. For example, a timing window for an activation timer and/or a deferred timer may be configured for the UE regarding the expected timing range, during which the triggering condition is evaluated and the triggering condition needs to be met in order to trigger a measurement report. In addition, for the second manner of the two manners mentioned above, the target UE may be provided with an indication of prediction quality with respect to the aforementioned expected timer or duration, e.g., a confidence area in which a positioning link quality will dramatically degrade inside the specified timing window.

Alternatively, the evaluation of the triggering condition may be triggered by an event change, for example, a motion change and/or an area change. FIG. 4 shows an exemplary sequence of signaling operations fora deferred activation of triggering condition, i.e. the second manner of activating triggering condition. Herein a location server, LS, is the entity, which controls the location resources and/or configuration of location signaling messages, and/or delivers positioning assistance data. It may be a location management function, LMF, a BS, PosTXUE or MasterUE. In stepl of FIG. 4, a trigger, and/or measurement report are configured from LS to PosRXUE/PosTXUE, including configuration of deferred activation on trigger. Then, step 2 of FIG. 4 indicates that activation of the trigger is deferred and the trigger only takes effect after the expiration of certain timer at PosRXUE/PosTXUE. In step 3 of FIG. 4 the trigger is performed. Then, the report is transmitted to location server in step 4 of FIG. 4.

FIG. 4 illustrates a measurement report initiated by deferred activation of a triggering condition. Triggering conditions:

Triggering conditions, also called trigger conditions, for a measurement report in PosRXUE- based positioning may be categorized into three types. Here it should be noted that the condition configured by the UE might be one of these three types or their combinations.

Type 0: Condition-free.

Type 1: Absolute Condition. This set of conditions allows for the evaluation on PRS resources from selected/all PRS resource sets. Herein the PRS resource set is defined as a resource set comprising multiple PRS resources. It may also include existing RSs, e.g., SSB, CSI-RS. It may also be specified as PRS resource set containing PRS resources, where each resource has an associated spatial transmission filter.

An absolute condition may be presented in the following form and its variations as explained later:

A sum S1 of receive signal quality, e.g., RSRPs, SNR, of one or more, e.g. X1, PRS resources, of selected/all PRS source sets, is smaller than a predefined threshold T1 for consecutive N1 measurement instances or time duration.

Different variations for the formulation of said absolute condition might be

The alternative of “sum of may be “average of”, “maximum of”, or “minimum of’.

The alternative of “receive signal quality” may be “time stamp”, “positioning measurement quality”.

The alternative of “smaller than” can be “smaller or equal than”, “larger than”, “larger or equal than”, or “inside” or “outside” a, pre-defined range.

An example for “Type 1” is shown in the left-hand side sub-figure of FIG. 5.

Type 2: Comparative condition(s): This set of one or more conditions allows for comparing PRS resources from different PRS resource sets or resources within the same PRS resource set.

A comparative condition may be presented in the following form and its variations will be provided later:

A sum S2 of receive signal quality, e.g., RSRPs, SNR, of one or more, e.g. X2, PRS resources, inside PRS resource sets, is smaller than that of one or more, e.g., X3, PRS resources, inside another, set of, PRS resource sets, S3 + offset for consecutive N2 measurement instances or time duration. Different variations can be

The alternative of “sum of” may be “average of”, “maximum of”, or “minimum of’.

The alternative of “receive signal quality” may be “time stamp”, “positioning measurement quality” or its difference, e.g., “receive signal quality RSRP difference”, “time stamp difference”, or “positioning measurement quality difference”.

The alternative of “smaller than” can be “smaller or equal than”, “larger than”, “larger or equal than”, or “inside” or “outside” a, pre-, defined range. Thus, a particular variation may be that a variation of a quality parameter of one or more PRS resources is equal and/or larger than a predefined threshold T2 for consecutive N2 measurement instances or time duration.

An example for “Type 2” is shown in the right-hand side sub-figure of FIG. 5, where S2 corresponds to resource set A and S3 corresponds to resource set B.

Indication and transmission of measurement report:

Two types of measurement report indications are proposed in this invention: one-stage and two-stage measurement report.

One-stage measurement report:

In a one-stage measurement report procedure, the measurement report is transmitted via control signaling. Either PosTXUE or a location server, LS, determines the follow-up actions using measurement reports, e.g., optimize, adapt or activate subsequent PRS transmissions. General signaling procedure of a one-stage measurement report is depicted in FIG. 6. After triggering the report at PosRXUE, step 1 of FIG. 6, either PosTXUE or LS can be the reception entity of the report, as shown as option 1A denoted Opt. 1A and option 1B denote Opt. 1B in the FIG. 6. Therefore, different control signaling are utilized to deliver the report message:

Opt 1 A: PosTXUE controls the collection of report. PC5-RRC/MAC-CE is used for report, SL- Cond-Report, over SL between PosRXUE and PosTXUE in step 2a of FIG. 6.

Opt 1B: LS controls the collection of report. LPP/RRC/MAC-CE/UCI (RRC/MAC-CE/UCI are used when the LS is the BS/TRP), uplink control information, are used for delivering a SL- report, SL-Cond-Report, message between PosRXUE and LS in step 2b of FIG. 6. Afterwards, LS signals the message, Activate-PRS-adaptation, to PosTXUE in step 3b of FIG. 6. Note that here the LS can be a network entity, LMF/BS/TRP, or some UE, master UE, wherein the message Activate-PRS-adaptation maybe be configured in a nominal way as on-demand PRS transmission. The report, SL-Cond-Report, may include one or more of the following: one or more boolean variable(s) (trigger indicator(s)) indicating the configured triggering condition is/are met. one or more condition index(es) indicating which of the triggering conditions is/are met. a characterization of the measurement results:

Results corresponding to the configured triggering condition: e.g., X best/worst PRS resources, and/or from selected PRS resource sets, Y, and/or Z best RSRP/measurement quality/time stamp and/or comparable offset O to thresholds.

Two-stage measurement report:

In a two-stage measurement report, a first part of the measurement report is compulsory and is indicated by a short control signaling, SL-1 stCond-report. The second part of the measurement report, SL-2ndCondReport, is optional and may be transmitted upon need, Req- 2nd-CondReport.

After the transmission of the first part of the measurement report, either PosTXUE or LS may activate the second part of the measurement report and/or directly start optimizing subsequent PRS or positioning procedures, e.g., starting initial beam alignment procedure only upon 1 ^st cond-report.

A general signaling procedure is described in FIG. 7. Analogous to one-stage measurement report, two options are provided:

Opt 1A:

PosTXUE controls the collection of report. PC5-RRC/MAC-CE is used for 1 ^st part of report, SL-1stCond-Report, over SL between PosRXUE and PosTXUE in step 2a. Optionally, Req- 2nd-CondReport is transmitted from PosTXUE to PosRXUE via PC5-RRC/MAC-CE/SCI, sidelink control information, asking explicitly for the second part of report in step 3a, wherein Req-2nd-CondReport message is delivered as a binary indication indicative of requesting 2 ^nd part of report. Resource for the second part of resource may need to be configured in step 4a. Afterwards, second part of report are delivered to PosTXUE via PC5-RRC/MAC-CE in step 5a.

Opt 1B:

LS controls the collection of report. LPP/RRC/MAC-CE/UCI (RRC/MAC-CE/UCI are used when the LS is the BS/TRP), uplink control information, are used for delivering first part of a SL-report, SL-1 stCond-Report, -message between PosRXUE and LS in step 2b. Afterwards, Req-2nd-CondReport is optionally transmitted from LS to PosRXUE via LPP/RRC/MAC- CE/DCI (RRC/MAC-CE/DCI are used when the LS is the BS/TRP), downlink control information, in step 3b, wherein Req-2nd-CondReport message is as a signaling for scheduling resource for the second part of report, sent by resource entity/LS. Then second part of report are delivered to LS via LPP/RRC/MAC-CE/UCI/PUSCH (RRC/MAC-CE/UCI/PUSCH are used when the LS is the BS/TRP), in step 4b. Subsequently, LS signals the message, Activate- PRS-adaptation, to PosTXUE via LPP/RRC/MAC-CE/DCI (RRC/MAC-CE/DCI are used when the LS is the BS/TRP), in step 5b.

The first part of the measurement report, SL-1 stCond-Report, includes one or more of the following:

Boolean variable(s) (trigger indicator) indicating the configured triggering condition is met.

Condition index of which triggering conditions is met a reporting completion indicator which indicates whether reporting is completed or whether a further measurement report follows;

The second part of the measurement report, optional, SL-2ndCond-Report, includes a reporting completion indicator which indicates whether reporting is completed or whether a further measurement report follows, and/or the detailed characterization of measurement results wherein these results correspond to the configured triggering condition: e.g., X best/worst PRS resources, and/or from selected PRS resource sets, Y, and/or Z best RSRP/measurement quality/time stamp and/or comparable offset O to thresholds.

In the following, we present two implementation examples of conditional measurement report procedures for sidelink positioning in two scenarios, namely UEs, which are in-coverage, and UEs, which are out-of-coverage.

Conditional measurement report for PRS optimization in-coverage scenario:

This scenario may be an indoor IOT/eHealth scenario with network-coordinated location service, V2X positioning when UEs are in-coverage, or other positioning between UEs in network coverage area.

In this context, FIG. 8 illustrates an exemplary scenario for conditionally report inside network coverage. More specifically, in FIG: 8, an exemplary scenario is depicted in which sidelink location service is provided when PosTXUE and PosRXUE are both in coverage. Agile and high-precision location service may benefit from PosTXUE’s, e.g., forklift, optimization of PRS transmission or positioning procedures to PosRXUE which are triggered by kinematic/motion sensor information, network-instructed trajectory information, and/or PosRXUE measurements.

A part of such a trigger can initiate a PosRXUE’s report on sensor information, side information, e.g., map, trajectory change, or measurement results, e.g., using proposed triggering conditions.

Furthermore, FIG. 9 illustrates signaling procedures of a conditional report using a trigger for an in-coverage scenario. In more detail, procedures of a conditional report for PRS optimization are shown in FIG. 9 with following details:

• Step 1: LMF or TRP transmits configuration information to the PosRXUE with respect to the settings of trigger, measurement, and report. Note that this step can also be, pre configured.

• Step 2: Trigger at PosRXUE. For example, the report is triggered by evaluating the triggering conditions, e.g., Type 0-2 conditions or combinations thereof)

• Step 3: One-stage or two-stage report is performed from PosRXUE to PosTXUE or LMF/TRP.

• Step 4: Using the report, PRS adaptation or optimization is determined.

Step 1-4 of FIG. 9 form report procedures using current positioning link quality. The conditional report may provide feedback including useful information from the PosRXUE to inform about the link quality in a timely manner, and provide insights for PRS optimization.

• Step 5: According to the new setting of PRS or positioning procedures, updated PRS configuration and updated configuration information for trigger and report, if necessary to be updated, are delivered to PosRXUE.

• Step 6 indicates the optimal step where deferred activation of trigger is executed

• Step 7: Same as step 2. Note that if the updated PRS setting is provided as direct enhancement of current setting, e.g., increase BW, power, and repetition, this step may be omitted.

• Step 8: Report, one-stage or two-stage, on newly configured PRS.

• Step 9 is optional, if further PRS optimization needs to be performed: For example, only use the newly configured PRS by revoking the previous PRS set.

Step 5-9 of FIG. 9 include procedures for PRS adaptation, report and update. The conditional report may provide useful information from PosRXUE about evaluation of updated PRS configuration. Assistance data for optimized PRS may be delivered, cf. step 5 of FIG. 9, and its evaluation may be performed, cf. steps 6-8 of FIG. 9, prior to the PRS switching/usage, e.g., red PRS resource replaces yellow resource in step 9 of FIG. 9. Conditional measurement report for PRS optimization out-of-coveraae scenario:

This scenario may be a V2X sidelink positioning in partial- or out of coverage, cf. FIG. 10, or any other positioning directly performed between UEs without network assistance. Here we assume a location server, LS, and a resource control entity reside inside the UE, e.g., PosTXUE is a location server in FIG. 11.

In this context, FIG. 10 illustrates an exemplary scenario for conditionally report outside network coverage. In more detail, in FIG. 10 a specific exemplary scenario for a V2X scenario is shown. Agile and high-precision location service may benefit from PosTXUE’s, e.g., traffic light, optimization of PRS transmission or positioning procedures to PosRXUE, which is triggered by kinematic/motion sensor information, network-instructed trajectory information, and/or PosRXUE measurements. Part of such trigger can initiate PosRXUE’s report on sensor information, side information, e.g., map, trajectory change, or measurement results, e.g., using proposed triggering conditions.

Furthermore, FIG. 11 illustrates signaling procedures of a conditional report using a trigger for out-of-coverage. Thus, the procedures of a conditional report for PRS optimization are depicted in FIG. 11 with following details:

• Step 1 : PosTXUE transmits configuration information to the PosRXUE with respect to the settings of trigger, measurement, and report. Note that this step can also be, pre-, configured.

• Step 2: Trigger at PosRXUE. For example, the report is triggered by evaluating the triggering conditions, e.g., Type 0, 1, 2 conditions or combinations thereof)

• Step 3: One-stage or two-stage report is performed from PosRXUE to PosTXUE.

• Step 4: Using the report, PRS adaptation or optimization is determined.

Step 1-4 forms the report procedures using current positioning link quality. The conditional report can feedback useful information from PosRXUE to inform the link quality in a timely manner, and provide insights for PRS optimization.

• Step 5: According to the new setting of PRS or positioning procedures, updated PRS configuration and updated configuration information for trigger and report, if necessary to be updated, are delivered to PosRXUE.

• Step 6 indicates the optimal step where deferred activation of trigger is executed.

• Step 7: This step is similar as step 2. Note that if the updated PRS setting is provided as a direct enhancement of current setting, e.g., increase BW, power, and repetition, this step is optional and may be omitted.

• Step 8: Report, one-stage or two-stage, on newly configured PRS. • Step 9 is optional, if further PRS optimization needs to be performed: For example, only use the newly configured PRS by revoking the previous PRS set.

Step 5-9 of FIG. 11 include procedures for PRS adaptation, report and update. The conditional report may provide useful information from PosRXUE about the evaluation of updated PRS configuration. Assistance data for adapted PRS may be delivered, step 5 of FIG. 11, and its evaluation can be performed, step 6-8 of FIG. 11, prior to the PRS switching/usage, e.g., red PRS resource replaces yellow resource in step 9 of FIG. 11.

The present disclosure allows for conditional triggering measurement report, which brings in four-fold benefits. Firstly, location service continuity is improved in dynamic scenarios for PosRXUE-based positioning, thus the mobility robustness of location service is also enhanced. Secondly, latency performance of positioning procedures is improved with reduced feedback resources compared to UE-assisted positioning. Thirdly, by applying two-stage measurement report with on-demand delivery of second stage report, feedback/report resource may be further reduced compared to one-stage report. Last but not the least, the proposed mechanism supports location service either in partial and/or out-of-coverage scenarios.

The present disclosure thus provides a conditional measurement report procedure of monitoring of the positioning link quality in UE-based positioning. The procedure consists of two main parts. The first part is configuration of triggering for measurement report using the measurement results on positioning link. Both absolute and comparative triggering conditions are proposed with different variations. Furthermore, deferred activation of triggering condition is provided. The second part is indication and transmission of measurement report once the triggering condition is met. Two sub-procedures have been addressed for this part: i) a one- stage measurement report via control signaling, and ii) a two-stage measurement report with optional second stage report. Signaling procedures to support aforementioned conditional report and indication are also introduced.

FIG. 12 illustrates a possible structure of a UE provided according to the embodiments of the present disclosure. This UE uses a modular design. For example, the UE 1300 in FIG. 12 that uses a modular design includes an obtaining module 1301, a determining module 1302, and an indicating and transmitting module 1303. The obtaining module 1301 may also be denoted a receiving module.

The UE 1300 is a UE for providing a measurement repot of positioning link quality. The obtaining module 1301 is configured to obtain a triggering condition for reporting a measurement of positioning link quality; the determining module 1302 is configured to determine to report the measurement of positioning link quality based on the triggering condition, and the indicating and transmitting module 1303 is configured to indicate and/or transmit the measurement report to a reception entity.

In the UE 1300, the indicating and transmitting module 1303 may being configured to indicate and/or transmit the measurement report and the indicating and transmitting module 1303 may be configured to: send a measurement report to a transmitting UE in a RRC or MAC CE signaling; or send a measurement report to a location server, LS, in a LPP, RRC, MAC CE, or uplink control information.

Here, for the UE 1300 as indicated in FIG. 12, the measurement report comprises at least one of: a trigger indicator which indicates whether a configured triggering condition is met; a condition index of which triggering condition is met; a reporting completion indicator which indicates whether reporting is completed or whether a further measurement report follows; and a measurement result corresponding to the triggering condition.

The obtaining module 1301 of the UE 1300 of FIG. 12 may be further configured to receive a scheduled resource for further measurement report transmission when the reporting completion indicator is included in the measurement report.

In the UE 1300 of FIG. 12, the indicating and transmitting module 1303 may be configured to send a second part of measurement report using the scheduled resource. The second part of measurement report may comprise the reporting completion indicator.

The obtaining module 1301 of the UE 1300 of FIG. 12 may be further configured to receive a measurement report from a second UE, wherein the measurement report comprises at least one of: a trigger indicator which indicates whether a configured triggering condition is met; a condition index of which triggering condition is met; a reporting completion indicator which indicates whether reporting is completed or whether a further measurement report follows; and a measurement result corresponding to the triggering condition.

In the UE 1300 of FIG. 12, the indicating and transmitting module 1303 may be configured to transmit a scheduling resource for further measurement report transmission when the reporting completion indicator is included in the measurement report.

FIG. 13 illustrates a possible structure of a location server, LS 1600, provided according to the embodiments of the present disclosure. This LS uses a modular design. For example, the LS 1600 in FIG. 13 that uses a modular design includes a configuration module 1601, and a receiving module 1602.

In FIG. 13, the configuration module 1601 of the LS 1600 is adapted to: configure a triggering condition for reporting a measurement of positioning link quality; receive a measurement report from a user equipment, UE; wherein the triggering condition comprises: a quality parameter of one or more PRS resources is equal and/or smaller than a predefined threshold T1 for consecutive N1 measurement instances or time duration; or a variation of a quality parameter of one or more PRS resources is equal and/or larger than a predefined threshold T2 for consecutive N2 measurement instances or time duration. For the LS 1600 of FIG. 13, the quality parameter may be one of receive signal quality, and positioning measurement quality. Furthermore, the measurement report may comprise at least one of: a trigger indicator which indicates whether a configured triggering condition is met; a condition index of which triggering condition is met; a reporting completion indicator which indicates whether reporting is completed or whether a further measurement report follows; and a measurement result corresponding to the triggering condition.

FIG. 14 is a simplified schematic diagram of another possible design structure of a UE in the foregoing embodiments. UE 1400 includes a transmitter 1401, a receiver 1402, a controller/processor 1403, a memory 1404, and a modem processor 1405.

For example, the transmitter 1401 may adjust (for example, perform analog conversion, filtering, amplification, and up-conversion on) an output sample to generate a transmit signal when the UE 1400 sends a message, and the transmit signal is transmitted by an antenna on an uplink. On a downlink, an antenna receives a downlink signal, and the receiver 1402 adjusts (for example, performs filtering, amplification, down-conversion, and digitization on) the downlink signal received from the antenna and provides an input sample. An encoder receives service data and a signaling message that need to be sent on an uplink, and processes (for example, formats, encodes, and interleaves) the service data and the signaling message, for example, an extended service request message, an LAU request, or the like whose service type is mobile originated in this embodiment of this application. A modulator further processes (for example, performs symbol mapping and modulation on) the encoded service data and signaling message and provides an output sample. A demodulator processes (for example, demodulates) the input sample and provides symbol estimation. A decoder processes (for example, performs de-interleaving and decoding on) the symbol estimation and provides decoded data and a decoded signaling message that are to be sent to the UE 1400. The encoder, the modulator, the demodulator, and the decoder may be implemented by the modem processor 1405. These units perform processing based on a radio access technology (for example, an access technology in LTE and another evolved system) used in a radio access network.

In an example, the controller/processor 1403 may be configured to support the UE 1400 in implementing a function that can be implemented by the processor 601 shown in FIG. 6. The memory 1404 stores program code and data that are used by the controller/processor 1403 to implement a corresponding function. The transmitter 1401 may be configured to support the UE 1400 in implementing a sending function that can be implemented by a transceiver. The receiver 1402 may be configured to support the UE 1400 in implementing a receiving function that can be implemented by the transceiver.

Based on a same concept as the foregoing method embodiments, an embodiment of this application further provides a computer readable storage medium. The computer readable storage medium stores some instructions. When these instructions are invoked and executed, a computer is enabled to perform a function of the UE in any one of the foregoing method embodiments or the possible designs of the foregoing method embodiments. The computer readable storage medium is not limited in the embodiments of this application. For example, the computer readable storage medium may be a RAM (random access memory, random access memory) or a ROM (read-only memory, read-only memory).

Based on a same concept as the foregoing method embodiments, an embodiment of this application further provides a computer program product. When the computer program product is run on a computer, the computer is enabled to perform a function of the UE in any one of the foregoing method embodiments or the possible designs of the foregoing method embodiments.

Based on a same concept as the foregoing method embodiments, an embodiment of this application further provides a chip. The chip may be coupled to a transceiver, and is configured to implement a function of the UE in any one of the foregoing method embodiments or the possible designs of the foregoing method embodiments. The chip may be a chip located in the UE provided in the embodiments of this application.

Based on a same concept as the foregoing method embodiments, an embodiment of this application further provides an apparatus. The apparatus includes a processing module and a communications interface. The processing module is configured to perform the steps performed by the UE in any one of the foregoing method embodiments or the possible designs of the method embodiments. The communications interface is used by the apparatus for communication. For example, the communications interface may have a function of a transceiver in any one of the foregoing method embodiments or the possible designs of the foregoing method embodiments.

In a possible design, the apparatus further includes a storage module, configured to store a program instruction and data that are necessary for the processing module.

In a possible design, the apparatus is a chip or a chip system.

This application is described with reference to the flowcharts and/or block diagrams of the method, the device (system), and the computer program product according to the embodiments of this application. It should be understood that computer program instructions may be used to implement each process and/or each block in the flowcharts and/or the block diagrams and a combination of a process and/or a block in the flowcharts and/or the block diagrams. These computer program instructions may be provided for a general-purpose computer, a dedicated computer, an embedded processor, or a processor of any other programmable data processing device to generate a machine, so that the instructions executed by a computer or a processor of any other programmable data processing device generate an apparatus for implementing a specific function in one or more processes in the flowcharts and/or in one or more blocks in the block diagrams.

These computer program instructions may be stored in a computer readable memory that can instruct the computer or any other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory generate an artifact that includes an instruction apparatus. The instruction apparatus implements a specific function in one or more processes in the flowcharts and/or in one or more blocks in the block diagrams.

These computer program instructions may be loaded onto a computer or another programmable data processing device, so that a series of operations and steps are performed on the computer or the another programmable device, thereby generating computer- implemented processing. Therefore, the instructions executed on the computer or the another programmable device provide steps for implementing a specific function in one or more processes in the flowcharts and/or in one or more blocks in the block diagrams. In this application, "at least one" means one or more, and "a plurality of' means two or more. "At least one (one piece) of the following" or a similar expression thereof refers to any combination of these items, including any combination of singular items (pieces) or plural items (pieces). For example, "at least one of a, b, or c" or "at least one of a, b, and c" may indicate: a, b, c, a-b (that is, a and b), a-c, b-c, or a-b-c, where a, b, and c may be in a singular or plural form.

It should be understood that sequence numbers of the foregoing processes do not mean execution sequences in various embodiments of this application. Some or all steps may be performed concurrently or in sequence. The execution sequences of the processes should be determined based on functions and internal logic of the processes, and should not be construed as any limitation on the implementation processes of the embodiments of this application.

For related parts between the method embodiments of this application, refer to each other. The apparatus provided in each apparatus embodiment is configured to perform the method provided in the corresponding method embodiment. Therefore, each apparatus embodiment may be understood with reference to a related part in a related method embodiment.

Structural diagrams of the apparatuses provided in the apparatus embodiments of this application merely show simplified designs of the corresponding apparatuses. In actual application, the apparatus may include any quantity of transmitters, receivers, processors, memories, and the like, to implement functions or operations performed by the apparatuses in the apparatus embodiments of this application.

Although some possible embodiments of this application have been described, a person skilled in the art can make changes and modifications to these embodiments once the person learns the basic inventive concept. Therefore, the following claims are intended to be construed as to cover the embodiments of this application and all changes and modifications falling within the scope of this application.

It should be well understood that a person skilled in the art can make various modifications and variations to this application without departing from the scope of this application. This application is intended to cover these modifications and variations of this application provided that they fall within the scope of protection defined by the following claims and their equivalent technologies.