Method, apparatus and computer program

Abstract

There is provided an apparatus comprising: means for obtaining congestion information related to sidelink positioning; and means for determining sidelink positioning reference signal configuration information to be used for sidelink positioning on the basis of the acquired congestion information.

Description

Technical Field

[0001] The present application relates to an apparatus, a method and a computer program. In particular, but not exclusively, the present application relates to congestion in a communication system. Background Art

[0002] A communication system can be considered as a facility that enables communication sessions between two or more entities, such as user terminals, base stations, and / or other nodes, by providing a carrier wave between the various entities involved in the communication path. A communication system can be provided, for example, by a communication network and one or more compatible communication devices. A communication session can include, for example, data communications for carrying communications such as voice, video, electronic mail (email), text messages, multimedia, and / or content data. Non-limiting examples of the services provided include two-way or multi-way calls, data communications, or multimedia services, and access to data network systems such as the Internet.

[0003] Communication systems and associated devices typically operate according to a given standard or specification that specifies what the various entities associated with the system are allowed to do and how it should be implemented. The communication protocols and / or parameters that should be used for the connection are also typically defined. An example of a communication system is UTRAN (3G radio). Other examples of communication systems are the Long Term Evolution (LTE) of the Universal Mobile Telecommunications System (UMTS) radio access technology, and the so-called 5G or New Radio (NR) networks. NR is being standardized by the 3rd Generation Partnership Project (3GPP). The Internet of Things (IoT) comprises a network of physical devices that can communicate over the Internet. The "Internet of Everything" has been referred to as the networked connection of people, processes, data, and things. Summary of the Invention

[0004] According to a first aspect, an apparatus is disclosed, comprising: means for acquiring congestion information related to sidelink positioning; and means for determining sidelink positioning reference signal configuration information to be used for sidelink positioning based on the acquired congestion information.

[0005] According to an example, the apparatus comprises means for obtaining location information of one or more user equipment for determining sidelink positioning reference signal configuration information.

[0006] According to an example, the congestion information includes one or more of the following items: channel busy rate; channel occupancy rate.

[0007] According to an example, the congestion information indicates that a first user equipment of the one or more user equipment is experiencing a relatively high congestion level and a second user equipment of the one or more user equipment is experiencing a relatively low congestion level.

[0008] According to an example, the sidelink positioning reference signal configuration information is configured for reducing usage of radio resources at the first user equipment.

[0009] According to an example, the sidelink positioning reference signal configuration information is configured for increasing usage of resources at the second user equipment.

[0010] According to an example, the second user equipment comprises a standby user equipment for sidelink positioning, and the apparatus comprises means for causing the second user equipment to become active in the sidelink positioning.

[0011] According to an example, sidelink positioning reference signal configuration information for one or more user equipments includes at least one transmission parameter, the at least one transmission parameter including at least one of the following items: bandwidth; transmission frequency; transmission power.

[0012] According to an example, the apparatus comprises means for storing a mapping table for use in performing determining sidelink positioning reference signal configuration information.

[0013] According to an example, the mapping table provides a mapping of congestion levels at the apparatus to percentages of one or more user equipment experiencing congestion levels below a threshold, and a mapping of congestion levels at the apparatus to sidelink positioning reference signal configuration information to be selected.

[0014] According to an example, the apparatus comprises coordination means comprising means for determining sidelink positioning reference signal configuration information for a plurality of respective user equipments to be used when transmitting positioning reference signals in sidelink positioning.

[0015] According to an example, the apparatus comprises one of: a target user equipment to be located; a base station; a location management function.

[0016] According to an example, the apparatus includes an anchor user equipment in sidelink positioning.

[0017] According to an example, the anchor user equipment comprises means for determining sidelink positioning reference signal configuration information for the anchor user equipment itself to be used when sending positioning reference signals in sidelink positioning.

[0018] According to an example, the apparatus comprises means for receiving congestion information.

[0019] According to some examples, the means for receiving congestion information is configured to receive the congestion information from one or more of: one or more user equipment; a base station; a location management function.

[0020] According to a second aspect, a device is provided, which includes at least one processor and at least one memory storing instructions, which instructions, when executed by the at least one processor, cause the device to at least: obtain congestion information related to sidelink positioning; and determine sidelink positioning reference signal configuration information to be used for sidelink positioning based on the obtained congestion information.

[0021] According to a third aspect, an apparatus is provided, comprising a circuit system for: acquiring congestion information related to sidelink positioning; and determining sidelink positioning reference signal configuration information to be used for sidelink positioning based on the acquired congestion information.

[0022] According to a fourth aspect, a method is provided, comprising: acquiring congestion information related to sidelink positioning; and determining sidelink positioning reference signal configuration information to be used for sidelink positioning based on the acquired congestion information.

[0023] According to an example, a method includes obtaining location information of one or more user equipment for determining sidelink positioning reference signal configuration information.

[0024] According to an example, the congestion information includes one or more of the following items: channel busy rate; channel occupancy rate.

[0025] According to an example, the congestion information indicates that a first user equipment of the one or more user equipment is experiencing a relatively high congestion level and a second user equipment of the one or more user equipment is experiencing a relatively low congestion level.

[0026] According to an example, the sidelink positioning reference signal configuration information is configured for reducing usage of radio resources at the first user equipment.

[0027] According to an example, the sidelink positioning reference signal configuration information is configured for increasing usage of resources at the second user equipment.

[0028] According to an example, a method comprises determining, by an apparatus comprising a coordination apparatus, sidelink positioning reference signal configuration information for a plurality of respective user equipments to be used when transmitting positioning reference signals in sidelink positioning.

[0029] According to an example, a method comprises determining, by means in an anchor user equipment, sidelink positioning reference signal configuration information for the anchor user equipment itself to be used when transmitting a positioning reference signal in sidelink positioning.

[0030] According to a fifth aspect, a non-transitory computer-readable medium is provided, which includes program instructions, which when executed by an apparatus causes the apparatus to at least perform the following items: obtain congestion information related to sidelink positioning; and determine sidelink positioning reference signal configuration information to be used for sidelink positioning based on the obtained congestion information.

[0031] According to a sixth aspect, a non-transitory computer-readable medium is provided, which includes program instructions stored thereon, and the program instructions are used to perform at least the following items: obtaining congestion information related to sidelink positioning; and determining sidelink positioning reference signal configuration information to be used for sidelink positioning based on the obtained congestion information.

[0032] According to the seventh aspect, a computer program comprising instructions is provided, which, when executed by an apparatus, causes the apparatus to at least perform the following: obtain congestion information related to sidelink positioning; and determine sidelink positioning reference signal configuration information to be used for sidelink positioning based on the obtained congestion information.

[0033] According to an eighth aspect, there is provided a computer program comprising instructions stored thereon for performing at least the following: obtaining congestion information related to sidelink positioning; and determining sidelink positioning reference signal configuration information to be used for sidelink positioning based on the obtained congestion information. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Embodiments will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0035] Figure 1 schematically illustrates a portion of a communication system according to an example;

[0036] Figure 2 is a signaling diagram according to an example;

[0037] Figure 3 is a signaling diagram according to an example;

[0038] Figure 4 is a signaling diagram according to an example;

[0039] Figure 5 is a signaling diagram according to an example;

[0040] Figure 6 shows a representation of a wireless communication device according to an example;

[0041] Figure 7 shows a representation of a control device according to an example;

[0042] Figure 8is a flow chart of a method according to an example;

[0043] Figure 9 is a schematic representation of a non-volatile storage medium. DETAILED DESCRIPTION

[0044] The present disclosure relates to sidelink (SL) positioning. A "sidelink" connection enables direct communication between two devices without the need for a base station to be involved in the transmission and reception of data traffic between the two devices. For example, SL communication can occur between two user equipments (UEs). In SL positioning, the UEs send and / or receive SL positioning reference signals (SLPRS) to each other via the SL interface. On these transmitted / received signals, the UE can perform one or more time-, angle-, or power-based measurements. Using these measurements, the UE can then calculate a position estimate. The position estimate can be in terms of absolute position or relative position, or range (e.g., relative distance, and / or angle).

[0045] Currently under discussion in 3GPP is whether SL PRS can be sent in a dedicated SL resource pool or using a resource pool shared with other SL services.

[0046] SL is expected to support high-density users with high traffic volume (e.g., a large number of vehicles at a city intersection sending cooperative awareness messages every 100ms). To avoid quality of service (QoS) degradation under high channel utilization, congestion control mechanisms have been introduced for SL communications, especially for autonomous SL resource allocation, such as "Mode 2" in 5G NR or RA "Mode 4" in LTE.

[0047] Release 16 does not specify a specific congestion control algorithm, but defines related metrics and possible countermeasures to reduce channel congestion. These metrics include channel busy rate (CBR) and channel occupancy rate (CR):

[0048] • CBR is defined as the ratio of occupied resources (determined by high received signal energy (S-RSSI)) in the last 100 subframes. CBR is a measure of the recent congestion present in the resource pool.

[0049] CR estimates the channel occupancy caused by the transmitter UE. CR counts the total number of subchannels that the UE has transmitted and will transmit in a window period of up to 1000ms including the current subframe. Therefore, CR is a measure of how much resources the UE has recently and will require in the near future.

[0050] Each SL packet is associated with a single priority value based on the QoS requirements of the message passed down from the upper layers to the physical layer.The priority value is sent in the first order Sidelink Control Information (SCI) associated with each transport block.

[0051] A UE can be (pre)configured with a set of CBR ranges, with each CBR range in the set being linked to a CR limit. When a UE finds that its CR exceeds the CR limit for its currently measured CBR range, it should reduce its CR to not exceed that limit. How this is done depends on the UE implementation.

[0052] The UE can modify the following transmission parameters per resource pool to reduce channel load:

[0053] 1. Number of subchannels: A UE can reduce its CR by limiting the number of subchannels it can utilize. If a UE needs to adapt a transport block (TB) to a reduced number of subchannels, it can utilize, for example, a higher-order modulation and coding scheme (MCS).

[0054] 2. Number of (re)transmissions: A UE can reduce its CR by limiting the number of (re)transmissions.

[0055] 3. Transmit power: The UE can reduce the CBR by reducing its transmit power. If the CBR is reduced to a value within the lower CBR range, the UE can utilize a higher CR limit.

[0056] Each of the packet priority and CBR may also be (pre)configured with a mapping to a range of transmission parameter values (e.g., a range of MCS values and / or a range of the number of subchannels, etc.). In this case, the UE selects its transmission parameter from the range corresponding to the dominant PPPP (ProSe per-packet priority), and / or CBR.

[0057] A potential problem identified in this disclosure is that SL positioning may suffer from SL congestion. For example, SL congestion may be caused by a high density of users generating frequent message traffic, which is typical in, for example, vehicle-to-everything (V2X) use cases.

[0058] When applying traditional congestion control mechanisms, SL PRS may be limited by the reduced number of subchannels. This may result in reduced bandwidth, reduced transmission frequency, or reduced transmit power. This may all lead to degradation of positioning QoS, such as in terms of accuracy and latency.

[0059] Considering that positioning services may be life-critical for many use cases (e.g., V2X, public safety), the present disclosure identifies that enhancements to congestion control mechanisms may be needed so that positioning services do not suffer QoS degradation under high channel load.

[0060] The present disclosure identifies that a SL positioning session typically involves multiple UEs. This is different from SL communication that is typically between two UEs. A SL positioning session may also involve the exchange of SL PRS, or positioning-related messages, between multiple UEs. In addition, different UEs within a single session may use different broadcast types, such as unicast / multicast / broadcast. As an example, for the sidelink time difference of arrival (SL-TDOA) positioning method (similar to DL-TDOA), multiple anchor UEs will send SL PRS to the target UE. The target UE can be considered as the UE to be located (i.e., the UE whose location or position is to be determined), and the anchor UE can be considered as the UE that supports the positioning of the target UE. When out of network coverage, in some examples, the UE can use a UE autonomous scheme, and the configuration and resource allocation of the transmission can be determined or coordinated by the target UE or another UE without involving any gNB or location management function (LMF). The present disclosure identifies that such settings in SL positioning can open up new possibilities for combating congestion.

[0061] Therefore, as will be described in more detail below, the present disclosure proposes, among other things, new mechanisms and related signaling that perform congestion control during SL positioning of a target UE. In an example, the congestion control mechanism enables positioning support to be coordinated among multiple anchor UEs. For example, positioning support load (such as bandwidth allocation and / or periodicity) can be allocated or offloaded (partially or completely) from one or more anchor UEs that are experiencing relatively high congestion to one or more anchor UEs that are experiencing relatively low congestion. In other words, anchor UEs with low congestion can provide assistance to the positioning work to reduce the burden on highly congested UEs. In an example, the spatial distribution between anchor UEs (i.e., location diversity) can be utilized to improve positioning accuracy. For example, in a congested situation, positioning accuracy can be improved by offloading SL congestion in the airspace based on the dynamic load conditions at different locations where the anchor UEs reside (e.g., from an overloaded area to an underloaded area). In some examples, this concept is referred to as SL Positioning Congestion Control (SPCC).

[0062] Therefore, for a group of UEs participating in a SL positioning session to locate a target UE, the SL PRS configuration of the UEs may be determined based at least on congestion level measurements (such as CBR and CR) and the location of one or more UEs in the session. Two main approaches are broadly proposed:

[0063] 1. A centralized solution involving a coordinator entity. The coordinator entity can be a UE, such as a target UE. The coordinator entity can also be another UE, such as an anchor UE. The coordinator can also be a network entity, such as a LMF or gNB. In this example, the coordinator entity configures the SL PRS for each UE (e.g., an anchor UE) in a session that sends the SL PRS. Here, each anchor UE reports its channel congestion level to the coordinating entity.

[0064] Each anchor UE may also report its own location to the coordinator entity. When an anchor UE reports its location along with the congestion level, this enables the location information to be used to determine how useful the anchor UE is to the target UE's positioning process. For example, if many anchor UEs are located close to each other, spreading the SL PRS load to another UE located elsewhere may be more useful than spreading the load to another co-located anchor UE. This is because, in some examples, the positioning accuracy of the target UE is optimized when there is a geographical spread of anchor UEs.

[0065] 2. Distributed solution, where each anchor UE that sends SL PRS in a positioning session autonomously determines its own SL PRS configuration. For example, each anchor UE may autonomously determine its own SL PRS configuration based on (pre-)configured rules. For example,

[0066] The (pre)configured rules may be mapping rules that map the congestion levels and geographic areas of the UE and other UEs to the SL PRS configuration of the UE. Here, each UE reports its channel congestion level and location to all other member UEs. In some examples of a distributed approach, a UE (e.g., a target UE) collects congestion-related measurements from all UEs and distributes this information to each UE (e.g., multicasting all measurements).

[0067] Figure 1 A system including a target UE 102 and anchor UEs 104 and 106 is schematically shown. Of course, there may actually be more than two anchor UEs. A UE may also be referred to as a user equipment. A network entity is also shown at 108. For example, the network entity 108 may include an LMF or a gNB. For the foregoing purposes, it may be assumed that there is a SL positioning session in which the anchor UEs 104 and 106 send SL PRS messages to help locate the target UE 102. As described above, the anchor UEs 104 and 106 may also send messages related to their location. The network or coordinator entity may then determine which positioning scheme to use (i.e., centralized or distributed). The network or coordinator entity may then send information about which scheme to use to any UE joining the session. In some examples, the session is (pre)configured with SPSCC enable / disable conditions that depend at least on the number of anchor UEs in the session.

[0068] The centralized and distributed solutions are discussed in more detail below.

[0069] Centralized solution

[0070] First reference Figure 2 , Figure 2Communications are shown between a coordinator entity 202 (in this case, a target UE), a first anchor UE 204 (UE1), and a second anchor UE 206 (UE2).

[0071] During a sidelink positioning session, the first anchor UE 204 and the second anchor UE 206 transmit an SL PRS to the target UE 202 (coordinator UE) based on a first SL PRS configuration (e.g., Config1_A, Config2_A). This is shown at S201 and S202. In some examples, the intended receiver of the SL PRS (e.g., target UE 202) performs positioning-related measurements on the SL PRS. These measurements may include one or more of: time-based measurements (e.g., time of arrival); phase-based measurements (e.g., carrier phase measurements); angle-based measurements (e.g., angle of arrival); and / or power-based measurements (e.g., RSRP reference signal received power). In some examples, the SL PRS is transmitted according to the SL PRS configuration preconfigured in the anchor UEs 204 and 206. In this example, initially the anchor UE 204 uses the SL_PRS configuration Config1_A, and the anchor UE 206 uses the SL_PRS configuration Config2_A.

[0072] At S203 and S204, the first anchor UE 204 and the second anchor UE 206 report information including congestion-related metrics to the coordinator UE 202. For example, the congestion-related metrics may include one or more of SL CBR and CR. Figure 2 In the example of FIG, anchor UE 204 reports a high congestion value, and anchor UE 206 reports a low congestion value. Anchor UEs 204 and 206 may also report their locations to target UE 202. In some examples, the reporting by anchor UEs 204 and 206 may be periodic. In some examples, the reporting by anchor UEs 204 and 206 may be event-triggered. For example, the triggering event may be a request by coordinator UE 202. Additionally or alternatively, the triggering event may be a channel congestion threshold being reached. The threshold may be (pre-)configured by coordinator UE 202 or the network.

[0073] At S205, based on the information received from the anchor UEs 204 and 206, the coordinator UE determines an updated or new SL PRS configuration (e.g., a second SL PRS configuration (Config1_B, Config2_B)) for the anchor UEs 204 and 206. For example, for anchor UEs reporting a high congestion level (e.g., a high CBR and a high CR), the coordinator UE 202 may change or modify the configuration to a SL PRS configuration with a reduced bandwidth, and / or a periodicity of SL PRS transmission, and a reporting frequency. Similarly, for anchor UEs reporting a low congestion level (e.g., a low CBR and a low CR), the coordinator UE 202 may increase the SL PRS bandwidth and / or the periodicity of SL PRS transmission. When determining the new SL PRS configuration, the coordinator UE 202 may take into account the positioning-related measurements measured by using the SLPRS of S201 and S202. For example, if the target UE cannot meet its positioning QoS requirements (e.g., accuracy, latency) based on current measurements, it may configure a new SL PRS with higher bandwidth and / or frequency.

[0074] In some examples, one or more other entities may determine a new SL PRS configuration. Intended receivers of SL PRS transmissions may report their measurements and / or provide feedback about the transmissions (e.g., indicating an increase / decrease in bandwidth, frequency, and / or power, etc.).

[0075] At S206 and S207, new configurations are sent to the first anchor UE 204 and the second anchor UE 206, respectively. For example, at S206, configuration Config1_B is sent to the anchor UE 204, and Config1_B may have a lower bandwidth than Config1_A. Similarly, at S207, Config2_B is sent to the anchor UE 206, and Config2_B may have a higher bandwidth than Config2_A.

[0076] As shown at S208 and S209 , the anchor UEs 204 and 206 then send subsequent SL PRSs according to the updated configurations ( Config1_B and Config2_B).

[0077] Figure 3 Another example of a centralized solution is shown. Figure 3 In the example, the coordinator entity is a network entity such as LMF or gNB308.

[0078] At S301 and S302, the first anchor UE 304 and the second anchor UE 306 report information including congestion-related metrics to the coordinator entity 308. For example, the congestion-related metrics may include one or more of SL CBR and CR. The anchor UEs 304 and 306 may also report their locations to the coordinator entity 308. Figure 3 In the example shown, anchor UE 304 is reporting a high congestion value, and anchor UE 306 is reporting a low congestion value. In some examples, the reporting by anchor UEs 304 and 306 can be periodic. In some examples, the reporting by anchor UEs 304 and 306 can be event-triggered. For example, the triggering event can be a request by coordinator entity 308. Additionally or alternatively, the triggering event can be a channel congestion threshold being reached. The threshold can be (pre-)configured by coordinator entity 302 or the network.

[0079] At S303, based on the information received from the anchor UEs 304 and 306, the coordinator entity 308 determines an updated or new SL PRS configuration (a second SL PRS configuration (e.g., Config1_B and Config2_B)) for the anchor UEs 304 and 306. For example, for anchor UEs reporting a high congestion level (e.g., a high CBR and a high CR), the coordinator entity 308 may change or modify the configuration to a SL PRS configuration with a reduced bandwidth and / or periodicity of SL PRS transmission. Similarly, for anchor UEs reporting a low congestion level (e.g., a low CBR and a low CR), the coordinator entity 308 may increase the SL PRS bandwidth and / or the periodicity of SL PRS transmission.

[0080] At S304 and S305, new SL PRS configurations are sent to the first anchor UE 304 and the second anchor UE 306, respectively. For example, at S304, configuration Config1_B is sent to the anchor UE 304. For example, Config1_B may have a lower bandwidth than Config1_A. Similarly, at S305, Config2_B is sent to the anchor UE 306. Config2_B may have a higher bandwidth than Config2_A.

[0081] In some examples, in addition to or as an alternative to the modified SL PRS configuration of an existing anchor UE, the coordinator entity (e.g., UE, or LMF, or gNB) may decide to suspend (or silence, or deactivate) SL PRS transmission for a specific anchor UE, and / or trigger (or initiate, or enable) and configure SL PRS transmission for a new UE that was not previously in the session.

[0082] For example, an anchor UE may be in standby mode. In this context, "standby mode" means that the UE is preparing to transmit SLPRS. In some examples, a standby anchor is selected during anchor selection along with the "active" anchor. The standby anchor only serves as the anchor for the session when activated / triggered. The coordinator entity can then decide to deactivate a particular anchor UE and activate the standby anchor UE instead, for example, based on CBR measurements and / or the locations of the active and standby UEs. Figure 4 This scenario is illustrated, which shows the communication between a coordinator entity 402 (e.g., UE, or LMF, or gNB), a first anchor UE 404, and a second anchor UE 406. Figure 4 In the example of , the anchor UE 406 is considered to be an anchor UE that is experiencing a low CBR.

[0083] At S401 , the coordinator entity 402 sends a standby indication to the anchor UE 406 , informing the UE 406 that it is a standby anchor UE.

[0084] As shown at S402, the anchor UE 404 sends a SL PRS to the coordinator entity 402, for example according to a first SL PRS configuration (eg, Config1_A). The coordinator entity may perform positioning-related measurements based on the SL PRS, and this may be used after S405.

[0085] At S403 and S404, the anchor UE 404 and the backup anchor UE 406 send information related to congestion related metrics to the coordinator entity 402. For example, the metrics include SL CBR and / or CR. Figure 4 In the example of , the anchor UE 404 reports a high value of congestion metric, and the anchor UE 406 reports a low value of congestion metric. The anchor UE 404 and the backup anchor UE 406 may also send their location information at this stage.

[0086] At S405, the coordinator entity 402 determines a new SL PRS configuration (e.g., a second SL PRS configuration) for the anchor UE. In this example, the coordinator entity 402 determines that the standby anchor UE 406 is more suitable than the active anchor 404 (e.g., because the anchor 404 has higher congestion than the anchor 406 and / or because the anchor 404 is located in a less desirable location than the standby anchor 406). In some embodiments, at S405, the coordinator entity may not change the SL PRS configuration configured for the standby UE, and the coordinator may activate the standby UE without additional configuration.

[0087] Therefore, at S406 , the coordinator entity 402 sends a notification to the anchor UE 404 to deactivate the anchor UE 404 .

[0088] At S407, the coordinator entity 402 sends a notification to the standby anchor 406 to activate the UE 406 as the active anchor role. At this stage (or in a separate stage), the coordinator entity 402 may also send a SL PRS configuration (e.g., Config2_A or Config2_B) to the anchor UE 406. In this case, the SL PRS configuration may be an updated / new SL PRS configuration or an old SL PRS configuration. Alternatively, the UE 406 may have been pre-configured with a SL PRS configuration to adopt when activated. Alternatively, the coordinator entity 402 sends only an activation notification to the standby UE, and the standby UE may send a SL PRS based on the pre-configured SL PRS configuration.

[0089] Then at S408 , the anchor 406 (which is now active and no longer standby) starts sending SL PRS to the coordinator entity 402 according to its SL PRS configuration.

[0090] Distributed solution

[0091] refer to Figure 5 , which shows the communication between the target UE 502, the first anchor UE 504, and the second anchor UE 506.

[0092] As shown at S501 and S502, the anchor UE transmits a SL PRS to the target UE 502. For example, the SL PRS may be transmitted according to a first SL PRS configuration that has been (pre-)configured in the anchor UEs 504 and 506. For example, the anchor UE 504 transmits the SL PRS according to the configuration Config1_A, and the anchor UE 506 transmits the SL PRS according to the configuration Config2_A. The target UE 502 may perform positioning-related measurements based on the SL PRS received at S501 and S502, and the measurement results may be used to determine a new SL PRS configuration.

[0093] In contrast to the centralized mechanism, in the distributed scheme the anchor UEs 504 and 506 do not report congestion-related metrics to the target UE 502. Instead, in the distributed scheme, the anchor UEs (or at least some of them) in a session share congestion-related metrics with each other.

[0094] exist Figure 5 In the example of , the anchor UE 504 reports congestion related metrics to the anchor UE 506 and vice versa. For example, the congestion related metrics may include one or more of SL CBR and CR. Figure 5In the example shown in FIG5 , anchor UE 504 is experiencing a high congestion value, and anchor UE 506 is experiencing a low congestion value. Anchor UEs 504 and 506 may also share their location information with each other. At S505, the target UE may send measurement reports and / or feedback regarding SL PRS transmissions to anchor UEs 504 and 506. These may be reported separately or together.

[0095] Based on the information received at S504 and / or at S505, the anchor UE 504 determines a new SL PRS configuration for itself (ie, the second SL PRS configuration (Config1_B)) at S506. In addition, the SL PRS configuration determination may also consider the QoS requirements of the target UE.

[0096] Based on the information received at S503 and / or at S505, the anchor UE 506 determines a new SL PRS configuration for itself (ie, the third SL PRS configuration (Config2_B)) at S507. In addition, the SL PRS configuration determination may also consider the QoS requirements of the target UE.

[0097] At S508, the anchor UE 504 notifies the target UE 502 of its new SL PRS configuration (Config1_B). For example, the new configuration may have a lower bandwidth than Config1_A (because the anchor UE 504 was experiencing high congestion). For example, the new configuration may be considered to be Config1_B, which is different from Config1_A.

[0098] At S509, the anchor UE 506 notifies the target UE 502 of its new SL PRS configuration (Config2_B). For example, the new configuration may have a higher bandwidth than Config2_A (because the anchor UE 506 was experiencing low congestion). For example, the new configuration may be considered Config2_B, which is different from Config2_A.

[0099] As shown at S510 and S511 , the anchor UE 504 and the anchor UE 506 start sending SL PRS to the target UE 502 respectively using their new configurations.

[0100] Referring back to S506 and S507, each anchor UE 504 and 506 determines a new SL PRS for itself. As discussed, in some examples, each anchor UE 504 and 506 does this autonomously, for example without sending a new SL PRS configuration from the coordinator entity.

[0101] In some examples, each anchor UE stores the mapping rules and uses the mapping rules when determining a new SL PRS configuration. In some examples, the mapping rules are stored as a lookup table (LUT) at each anchor UE 504 and 506. An example LUT is shown in Table 1 below.

[0102]

[0103]

[0104] Table 1: SL PRS configuration and CBR mapping table

[0105] As shown, the table maps different SL PRS configurations (e.g., bandwidth and periodicity) to different congestion metric values (e.g., CBR or CR) for the UE using the mapping table (e.g., the anchor UE), and to different percentages of other UEs (e.g., other anchor UEs) in the SL positioning session (e.g., based on the percentage of other anchor UEs having a congestion metric (e.g., CBR or CR) below a certain threshold).

[0106] For example, let's say anchor UE 504 wants to determine which SL PRS configuration it needs to apply. In this example, assume that between 0% and 25% of the anchor UEs in a session have a congestion metric (e.g., SL CBR) below a certain threshold (e.g., 0.75). In some examples, anchor UE 504 will learn this information by communicating with other anchor UEs (e.g., anchor UE 506). The first row in column 1 of the table will then be reviewed. Then, assume, for example, that anchor UE 504 is experiencing a congestion metric of CBR_level_2 (e.g., 0.34 to 0.66). Anchor UE 504 then reviews the second subrow (CBR_level_2 (e.g., 0.34 to 0.66)) within the first row of the second column of the table. Reading through the table, anchor UE 504 determines that it needs to apply SL_PRS Config_2. Other anchor UEs (e.g., anchor UE 506) will perform a similar process.

[0107] Therefore, it should be understood that in some examples, the anchor UE collects CBR information of other UEs (e.g., other anchor UEs) to determine the relevant PRS configuration. In another example, the congestion metric information (e.g., CBR or CR) of other UEs can be collected by the anchor UE from a centralized entity (e.g., gNB or LMF).

[0108] In some examples, the mapping table itself and, for example, the predefined thresholds therein are determined by a network entity such as the LMF. In other examples, the contents of the mapping table may be determined by the gNB or UE and then shared with other entities such as the anchor UE.

[0109] In some examples, the mapping table may also take into account the spatial distribution of anchor UEs. For example, the mapping table may have a column containing information about the relative position of the target UE to each anchor UE (e.g., distance from each other, direction, etc.). For example, the spatial distribution of the UEs may be represented by the relative position, and / or absolute position, of the UEs. In some examples, the values may be provided in meters (although other units such as cm, km, etc. may also be used). In some examples, the spatial distribution information is dynamically updated to take into account moving UEs. In some examples, the updates are periodic. In some examples, the updates are triggered based on, for example, the UE moving a distance greater than a threshold value X m.

[0110] In some examples, the mapping table may also take into account the QoS requirements of the target UE. For example, the mapping table may have a column indicating the QoS level of the target UE. QoS parameters may include, for example, accuracy, and / or latency.

[0111] In some examples, the spatial distribution information of the anchor UEs includes geometric dilution of precision (GDOP) information.

[0112] In some examples, the inter-UE distance between anchor UEs may be taken into account. For example, the first column in Table 1 may then include additional information such as "the percentage of other UEs with an SL CBR below a threshold SL CBR_thr_1 (e.g., 0.75) and an average inter-UE distance above a certain threshold (e.g., 50 m).

[0113] In some examples, Table 1 (or similar tables) can also be used in a centralized solution. Figure 2 S205 in the Figure 3 In the case where the new SL PRS value at S303 in FIG. 1 is determined, Table 1 (or a similar table) may be used.

[0114] In some examples, one aspect of the selected SL PRS configuration includes transmit power. That is, according to some examples, the transmit power of the SL PRS by the anchor UE depends on the selected configuration.

[0115] It should be understood that the proposed concept allows the target UE to locate itself with high accuracy even when one or more anchor UEs of the target UE face higher SL congestion. That is, according to some examples, adaptation of the SL positioning session is performed to reduce or mitigate the impact of SL congestion at one or more anchor UEs on session performance.

[0116] Figure 6An example of a terminal 600 is shown. Terminal 600 can be provided by any device capable of sending and receiving radio signals. Non-limiting examples include user equipment, user equipment, a mobile station (MS), or a mobile device such as a mobile phone or a so-called "smartphone," a computer provided with a wireless interface card or other wireless interface facility (e.g., a USB dongle), a personal digital assistant (PDA) or tablet provided with wireless communication capabilities, a machine type communication (MTC) device, an Internet of Things (IoT) type communication device, or any combination of these devices. Terminal 600 can provide, for example, data communications for carrying communications. The communications can be one or more of voice, electronic mail (email), text messaging, multimedia, data, machine data, etc.

[0117] The terminal 600 may receive signals through the air interface, or radio interface 607, via appropriate means for receiving, and may transmit signals via appropriate means for transmitting radio signals. Figure 6 In FIG, the transceiver arrangement is schematically represented by block 606. The transceiver arrangement 606 may be provided, for example, by a radio part and an associated antenna arrangement. The antenna arrangement may be arranged internally or externally to the mobile device.

[0118] Terminal 600 may be provided with at least one processor 601, at least one ROM 602a, at least one RAM 602b, and other possible components to assist in performing its designed tasks with software and hardware, including controlling access to and communication with access systems and other communication devices. Data processing, storage, and other related control devices may be provided on appropriate circuit boards and / or in chipsets. This feature is indicated by reference numeral 604.

[0119] The device may optionally have a user interface, such as a keyboard 605, a touch-sensitive screen or pad, a combination thereof, etc. Depending on the type of device, one or more of a display 608, a speaker, and a microphone may optionally be provided.

[0120] UE (such as Figures 1 to 5 The target UE and anchor UE discussed in Figure 6 The form of the UE is schematically shown in FIG.

[0121] Figure 7An example of a control device for a communications system is shown, for example, coupled to and / or used to control a station of the access system, such as a RAN node, e.g., a base station, gNB, a central unit of a cloud architecture, or a node of a core network (such as an MME or S-GW), or a scheduling entity (such as a spectrum management entity, LMF, or a server or host). The control device may be integrated with a node or module of the core network or RAN, or external thereto. In some embodiments, the base station includes a separate control device unit or module. In other embodiments, the control device may be another network element, such as a radio network controller or spectrum controller. In some embodiments, each base station may have such a control device, as well as a control device provided in the radio network controller. The control device 700 may be arranged to provide control of communications within the service area of the system. The control device 700 includes at least one memory 701, at least one data processing unit 702, 703, and an input / output interface 704. Via this interface, the control device may be coupled to a receiver and transmitter of the base station. The receiver and / or transmitter may be implemented as a radio front end or a remote radio head. For example, the control device 700 or the processor 701 may be configured to execute appropriate software code to provide control functions. Figure 1 and Figure 3 The network entity in question (such as LMF or gNB) may take the following actions: Figure 7 The form of the control device shown in .

[0122] Figure 8 is a flowchart of a method according to an example. Figure 8 The flowchart can be viewed from the perspective of an apparatus. For example, the apparatus may be a coordinator entity. The coordinator entity may be a UE (e.g., a target UE; an anchor UE) or provided in a UE, or may be a network entity (e.g., a LMF; a gNB) or provided in a network entity. As shown at S801, the method includes obtaining congestion information related to sidelink positioning. As shown at S802, the method includes determining sidelink positioning reference signal configuration information to be used for sidelink positioning based on the obtained congestion information. Figure 8 Described Figures 2 to 5 part of the signal flow, and Figures 2 to 5 The rest of the Figure 8 .

[0123] Figure 9 Schematic representations of non-volatile storage media 900a (e.g., a compact disc (CD) or digital versatile disc (DVD)) and 900b (e.g., a universal serial bus (USB) memory stick) storing instructions and / or parameters 902 that, when executed by a processor, allow the processor to perform Figure 8 One or more steps in a method.

[0124] It should be understood that the apparatus may include, or be coupled to, other units or modules used in transmission and / or reception, such as a radio section or a radio head. Although the apparatus has been described as one entity, the different modules and memories may be implemented in one or more physical or logical entities.

[0125] It should be noted that although some embodiments have been described with respect to 5G networks, similar principles may be applied to other networks and communication systems. Thus, although certain embodiments above have been described by way of example with reference to certain example architectures for wireless networks, technologies, and standards, the embodiments may be applied to any other suitable form of communication system in addition to the communication system shown and described herein.

[0126] It is also noted herein that while the above describes example embodiments, there are numerous variations and modifications which may be made to the disclosed solution without departing from the scope of the present invention.

[0127] As used herein, “at least one of: ” and “at least one of ” and similar expressions (where a list of two or more elements is connected by “and” or “or”) refer to at least any one of these elements, or at least any two or more of these elements, or at least all of these elements.

[0128] In general, various embodiments may be implemented in hardware or dedicated circuitry, software, logic, or any combination thereof. Some aspects of the present disclosure may be implemented in hardware, while other aspects may be implemented in firmware or software, which may be executed by a controller, microprocessor, or other computing device, although the present disclosure is not limited thereto. Although various aspects of the present disclosure may be shown and described as block diagrams, flow charts, or using some other graphical representation, it should be understood that, as non-limiting examples, the blocks, devices, systems, techniques, or methods described herein may be implemented in hardware, software, firmware, dedicated circuitry or logic, general-purpose hardware or controller, or other computing device, or some combination thereof.

[0129] As used in this application, the term "circuitry" may refer to one or more or all of the following:

[0130] (a) hardware circuit implementation only (such as implementation only in analog and / or digital circuitry) and

[0131] (b) a combination of hardware circuitry and software such as (as applicable):

[0132] (i) a combination of analog and / or digital hardware circuits and software / firmware, and

[0133] (ii) any portion of hardware processor(s) (including digital signal processor(s)) with software, software, and memory(s) that work together to enable a device (such as a mobile phone or server) to perform various functions, and (c) hardware circuit(s) and / or processor(s), such as microprocessor(s) or portion(s) of microprocessor(s), that requires software (e.g., firmware) for operation, but in which case the software may not be present when not required for operation.

[0134] This definition of circuitry applies to all uses of the term in this application, including in any claims. As a further example, as used in this application, the term circuitry also encompasses merely a hardware circuit, or a processor (or multiple processors), or a portion of a hardware circuit or processor, and its (or their) accompanying software and / or firmware implementation. For example, and if applicable to a particular claim element, the term "circuitry" also encompasses a baseband integrated circuit or processor integrated circuit for a mobile device, or a similar integrated circuit in a server, cellular network device, or other computing or network device.

[0135] The embodiments of the present disclosure may be implemented by computer software executed by a data processor (such as a processor entity) of a mobile device, or by hardware, or by a combination of software and hardware. Computer software or programs (also referred to as program products, including software routines, applets and / or macros) may be stored in a data storage medium readable by any device, and they include program instructions for performing specific tasks. A computer program product may include one or more computer executable components that are configured to execute an embodiment when the program is running. One or more computer executable components may be at least one software code or a portion thereof.

[0136] In addition, it should be noted in this regard that any block of the logic flow shown in the figure can represent a program step, or interconnected logic circuits, blocks and functions, or a combination of program steps and logic circuits, blocks and functions. The software can be stored on a physical medium such as a memory chip, or a memory block implemented within a processor, a magnetic medium such as a hard disk or floppy disk, and an optical medium such as a DVD and its data variant CD. A physical medium is a non-transient medium.

[0137] The term "non-transitory" as used herein is a restriction on the medium itself (ie, tangible, not a signal), not on the persistence of the data storage (eg, RAM vs. ROM).

[0138] The memory may be of any type suitable for the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and removable memory. The data processor may be of any type suitable for the local technical environment and may include, by way of non-limiting example, one or more of the following: a general-purpose computer, a special-purpose computer, a microprocessor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an FPGA, a gate-level circuit, and a processor based on a multi-core processor architecture.

[0139] Embodiments of the present disclosure can be practiced in various components, such as integrated circuit modules. The design of integrated circuits is generally a highly automated process. Complex and powerful software tools are available for converting a logic-level design into a semiconductor circuit design ready to be etched and formed on a semiconductor substrate.

[0140] The scope of protection sought by the various embodiments of the present disclosure is defined by the independent claims. Embodiments and features described in this specification that do not fall within the scope of the independent claims (if any) are to be construed as examples that help to understand the various embodiments of the present disclosure.

[0141] The foregoing description provides a complete and informative description of exemplary embodiments of the present disclosure by way of non-limiting examples. 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. Nevertheless, all such and similar modifications of the teachings of the present disclosure will still fall within the scope of the present invention as defined by the appended claims. Indeed, there are additional embodiments, including combinations of one or more embodiments with any other embodiments previously discussed.

Claims

1. A device comprising: means for obtaining congestion information associated with sidelink positioning; as well as means for determining sidelink positioning reference signal configuration information to be used for the sidelink positioning based on the acquired congestion information.

2. The apparatus according to claim 1, comprising: Means for obtaining location information of one or more user equipments for determining said sidelink positioning reference signal configuration information.

3. The apparatus according to claim 1 or claim 2, wherein the congestion information comprises one or more of the following items: channel busy rate; channel occupancy rate.

4. The apparatus according to claim 2 or claim 3, wherein the congestion information indicates that a first user equipment among the one or more user equipments is experiencing a relatively high congestion level, and a second user equipment among the one or more user equipments is experiencing a relatively low congestion level. 5 . The apparatus according to claim 4 , wherein the sidelink positioning reference signal configuration information is configured to reduce usage of radio resources at the first user equipment. 6 . The apparatus according to claim 4 , wherein the sidelink positioning reference signal configuration information is configured to increase usage of resources at the second user equipment.

7. The apparatus according to any one of claims 4 to 6, wherein the second user equipment comprises: A backup user equipment is provided for said sidelink positioning, and said apparatus comprises means for causing said second user equipment to become active in said sidelink positioning.

8. An apparatus according to any one of claims 1 to 5, wherein the sidelink positioning reference signal configuration information for one or more user equipment includes at least one transmission parameter, and the at least one transmission parameter includes at least one of the following items: bandwidth; transmission frequency; transmission power.

9. The device according to any one of claims 1 to 8, wherein the device comprises: Means for storing a mapping table for use in performing determination of sidelink positioning reference signal configuration information.

10. The apparatus of claim 9, wherein the mapping table provides: a mapping of a congestion level at the apparatus to a percentage of one or more user equipment experiencing a congestion level below a threshold, and a mapping of the congestion level at the apparatus to sidelink positioning reference signal configuration information to be selected.

11. The apparatus according to any one of claims 1 to 10, wherein the apparatus comprises a coordination device, the coordination device comprising: means for determining sidelink positioning reference signal configuration information for a plurality of corresponding user equipments to be used when transmitting positioning reference signals in said sidelink positioning.

12. The apparatus according to claim 11, comprising one of the following: a target user equipment to be located; a base station; a location management function.

13. The device according to any one of claims 1 to 10, wherein the device comprises: An anchor user equipment in the sidelink positioning.

14. The apparatus according to claim 13, wherein the anchor user equipment comprises: A means for determining sidelink positioning reference signal configuration information for the anchor user equipment itself to be used when transmitting a positioning reference signal in the sidelink positioning.

15. The device according to any one of claims 1 to 14, comprising: means for receiving said congestion information.

16. A method comprising: Obtaining congestion information related to sidelink positioning; as well as Based on the acquired congestion information, sidelink positioning reference signal configuration information to be used for the sidelink positioning is determined.

17. The method according to claim 16, further comprising: Acquire location information of one or more user equipments for determining the sidelink positioning reference signal configuration information.

18. The method according to claim 16 or claim 17, wherein the congestion information comprises one or more of the following items: channel busy rate; channel occupancy rate.

19. The method of claim 17 or claim 18, wherein the congestion information indicates that a first user equipment of the one or more user equipment is experiencing a relatively high congestion level, and a second user equipment of the one or more user equipment is experiencing a relatively low congestion level.

20. The method according to claim 19, wherein the sidelink positioning reference signal configuration information is configured to reduce usage of radio resources at the first user equipment.

21. The method according to claim 19 or claim 20, wherein the sidelink positioning reference signal configuration information is configured to increase usage of resources at the second user equipment.

22. The method according to any one of claims 16 to 21, further comprising: The coordination device determines, for a plurality of corresponding user equipments, sidelink positioning reference signal configuration information to be used when transmitting positioning reference signals in the sidelink positioning.

23. The method according to claims 16 to 21, further comprising: The device in the anchor user equipment determines sidelink positioning reference signal configuration information for the anchor user equipment itself to be used when transmitting a positioning reference signal in the sidelink positioning.

24. A computer program comprising instructions for causing an apparatus to at least perform the following: Obtaining congestion information related to sidelink positioning; and Based on the acquired congestion information, sidelink positioning reference signal configuration information to be used for the sidelink positioning is determined.

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