Beam measurement resource determination

Abstract

In accordance with an example embodiment of the present invention, an apparatus or method for receiving a configuration for event based beam reporting; receiving a configuration activation of one or more TCI states; receiving an indication designating an activated TCI as a current indicated TCI state; determining that a quasi co located (QCL) source reference signal (RS) of the current indicated TCI state is a tracking reference signal (TRS); determining whether the TRS is a QCL source RS for more than one channel state information RSs (CSI-RSs); and in response to determining that the TRS is a QCL source RS for more than one CSI-RSs, selecting a synchronization signal / physical broadcast channel block (SSB) that is a QCL source RS for the TRS as RS for measurement for event based beam reporting.

Description

BEAM MEASUREMENT RESOURCE DETERMINATIONTECHNICAL FIELD

[0001] The present application claims priority from, and the benefit of, US Provisional Application No. 63 / 651773, filed May 24, 2024, which is hereby incorporated by reference in its entirety.TECHNICAL FIELD

[0002] The present application relates generally to determination of beam measurement resources.BACKGROUND

[0003] In the development of 3 GPP NR Rell9 MEMO, facilitating user equipment (UE) initiated / event-driven beam management is being considered, motivated by the consideration that UEs have better and more-timely knowledge of beam quality changes at the UE than network nodes, which can mitigate inadequate or overly burdensome reporting requirements from network nodes.

[0004] Among events triggering such beam management, at least the following are considered:Event- 1 : Quality of the current beam is worse than a certain threshold.Event-2: Quality of at least one new beam, such as physical layer reference signal receiver power (Ll-RSRP), becomes a threshold value better than the current beam.Event-3 : Quality of a new beam is better than a certain threshold.Event-4: Quality of the current beam is worse than a threshold 1, and quality of at least one new beam is better than a threshold 2.

[0005] For certain of the events considered for UE iniated / event-driven beam management, it is necessary to determine the quality of a current beam and for certain embodiments of determining the quality of the current beam, it is necessary to determine a reference signal (RS) for measurement. For at least Event-2, it has been agreed that the RS for the current beam is implicitly derived from a quasi co located (QCL) RS of an indicatedtransmission configuration indication (TCI) state, which in the below citation of 3 GPP Rl- 2404714 (3GPP TSGRAN WG1#117, Moderator Summary #2 on UE-initiated / event-driven beam management) is coloqually referred to as “Option-2a”.

[0006] An unresolved aspect for further study (FFS) in such implicit derivation of the RS for the current beam is the situation in which a single tracking reference signal (TRS) is configured in the indicated TCI state (as this implies that there is no RS in the TCI state supported for beam measurements), as noted in 3GPP R1 -2404714 as follows:

[0007] In addition to the above, additional implicit schemes for Event-2, Option-2a are proposed as follows:

[0008] At least one issue to consider with the RS for the current beam being a channel state information RS (CSI-RS) for beam management derived from the QCL RS in the indicatedTCI state, is that a TRS may be using a wide synchronization signal / physical broadcast channel block (SSB) beam or a narrow CSI-RS beam, such that using CSI-RS measurement to determine the quality of the current beam would give an inaccurate indication to a network if the network were using an SSB beam as TRS of the current beam.

[0009] For the alternative scheme of introducing TRS as quality measurement RS for a current beam, it is considered that this would likely introduce undesirable significant delay in the completion of 3GPP NR Rell9 specifications. A TRS is presently generally defined as an RS for the purpose of allowing a UE to track and compensate time and frequency offsets (deviations), but not for quality measurement reporting.

[0010] It is hence an objective of the present application to implicitly determine an RS for measurement when a single TRS is configured in an indicated TCI state, such that the network can freely elect to a wide (e.g. SSB) beam or a narrow (e.g. CRI-RS) beam for TRS.SUMMARY

[0011] Various aspects of examples of the invention are set out in the claims.

[0012] According to a first aspect of the present invention, there is disclosed an apparatus, comprising: at least one processor; and at least one memory including computer program code the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to at least: receive a configuration for event based beam reporting; receive a configuration activation of one or more TCI states; receive an indication designating an activated TCI as a current indicated TCI state; determine that a quasi co located (QCL) source reference signal (RS) of the current indicated TCI state is a tracking reference signal (TRS); determine whether the TRS is a QCL source RS for more than one channel state information RSs (CSLRSs); and in response to determining that the TRS is a QCL source RS for more than one CSLRSs, select a synchronization signal / physical broadcast channel block (SSB) that is a QCL source RS for the TRS as RS for measurement for event based beam reporting.

[0013] According to a second aspect of the present invention, there is disclosed an apparatus, comprising: at least one processor; and at least one memory including computer program code the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to at least: receive a configuration for event based beam reporting; receive a configuration activation of one or more TCI states; receive an indicationdesignating an activated TCI as a current indicated TCI state; determine that a quasi co located (QCL) source reference signal (RS) of the current indicated TCI state is a tracking reference signal (TRS); in response to determining that the QCL source RS of the current indicated TCI state is a TRS, establish from a configuration of the TRS that the TRS is transmitted using a channel state information RS (CSLRS) configured for beam manament; and in response to the establishing, select the CSLRS configured for beam management, of which the TRS is a QCL source RS, as RS for measurement for event based beam reporting.

[0014] According to a third aspect of the present invention, there is disclosed an apparatus, comprising: at least one processor; and at least one memory including computer program code the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to at least: receive a configuration for event based beam reporting; receive a configuration activation of one or more TCI states; receive an indication designating an activated TCI as a current indicated TCI state; determine that a quasi co located (QCL) source reference signal (RS) of the current indicated TCI state is a tracking reference signal (TRS); in response to determining that the QCL source RS of the current indicated TCI state is a TRS, establishing from a channel state information RS (CSLRS) configuration for beam management that a CSLRS configured for beam management and a TRS of the current indicated TCI state represent a same beam; and in response to the establishing, selecting the CSL RS configured for beam management, of which the TRS is a QCL source RS, as RS for measurement for event based beam reporting.

[0015] According to a fourth aspect of the present invention, there is disclosed a method for a user equipment, comprising: receiving a configuration for event based beam reporting; receiving a configuration activation of one or more TCI states; receiving an indication designating an activated TCI as a current indicated TCI state; determining that a quasi co located (QCL) source reference signal (RS) of the current indicated TCI state is a tracking reference signal (TRS); determining whether the TRS is a QCL source RS for more than one channel state information RSs (CSLRSs); and in response to determining that the TRS is a QCL source RS for more than one CSLRSs, selecting a synchronization signal / physical broadcast channel block (SSB) that is a QCL source RS for the TRS as RS for measurement for event based beam reporting.

[0016] According to a fifth aspect of the present invention, there is disclosed a method for a user equipment, comprising: receiving a configuration for event based beam reporting; receiving a configuration activation of one or more TCI states; receiving an indication designating an activated TCI as a current indicated TCI state; determining that a quasi co located (QCL) source reference signal (RS) of the current indicated TCI state is a tracking reference signal (TRS); in response to determining that the QCL source RS of the current indicated TCI state is a TRS, establishing from a configuration of the TRS that the TRS is transmitted using a channel state information RS (CSLRS) configured for beam manament; and in response to the establishing, selecting the CSLRS configured for beam management, of which the TRS is a QCL source RS, as RS for measurement for event based beam reporting.

[0017] According to a sixth aspect of the present invention, there is disclosed a method for a user equipment, comprising: receiving a configuration for event based beam reporting; receiving a configuration activation of one or more TCI states; receiving an indication designating an activated TCI as a current indicated TCI state; determining that a quasi co located (QCL) source reference signal (RS) of the current indicated TCI state is a tracking reference signal (TRS); in response to determining that the QCL source RS of the current indicated TCI state is a TRS, establishing from a channel state information RS (CSLRS) configuration for beam management that a CSLRS configured for beam management and a TRS of the current indicated TCI state represent a same beam; and in response to the establishing, selecting the CSL RS configured for beam management, of which the TRS is a QCL source RS, as RS for measurement for event based beam reporting.BRIEF DESCRIPTION OF THE DRAWINGS

[0018] For a more complete understanding of example embodiments of the present invention, reference is now made to the following descriptions taken in connection with the accompanying drawings in which:

[0019] FIGURE 1 illustrates embodiments in accordance with the invention;

[0020] FIGURE 2 illustrates embodiments in accordance with the invention;

[0021] FIGURE 3 illustrates embodiments in accordance with the invention; and

[0022] FIGURE 4 illustrates an example wireless apparatus in accordance with an example embodiment of the invention.DETAILED DESCRIPTON

[0023] FIGURE 1 , FIGURE 2 and FIGURE 3 depict various embodiments in accordance with the invention.

[0024] At 110, a UE receives a configuration for event based beam reporting. The configuration may be associated with a specific event, such as the quality of at least one new beam, such as Ll-RSRP, becoming a threshold value better than a current beam. The configuration may also be associated a selective plurality of events defined or configured for event based beam reporting, or with all events defined or configured for the UE for event based beam reporting. The configuration may for example comprise an indication of one or more events to be used to trigger event based beam reporting, one or more thresholds for one or more events for event based beam reporting and / or an indication that that the UE may or shall use event based beam reporting.

[0025] At 120, the UE receives one or more configuration activations of one or more TCI states. The configuration activation may for example comprise a configuration of one or more TCI states to be activated or may comprise an indication to activate one or more previously configured TCI states. The configuration for event based beam reporting and the one or more configuration activations of one or more TCI states can be received in any order.

[0026] At 130, the UE receives an indication of a TCI state to be considered a current indicated TCI state. The current indicated TCI state is typically an activated TCI state.

[0027] At 140, the UE determines that a QCL source of the current indicated TCI state is a TRS. The QCL source may for example be a QCL-D source, wherein QCL-D defined in accordance with 3GPP NR to mean that each TCI state has a distinct spatial QCL assumption. In general in the present context, a QCL source provides a downlink RS to be used as reference for directionality of beams of other signals to be received and / or transmitted by the UE.

[0028] Now at 150 in FIGURE 1, the UE determines whether the TRS is a QCL source RS for more than one CSI-RSs for beam management. This may be performed by checking for CSI-RSs configured for beam management whether the TRS is a QCL source RS, where the checking may be for all CSI-RSs, or the checking may be terminated when at least two CSI-RSs are found for which the TRS is a QCL source RS.

[0029] If the UE determines at 160 that the TRS is a QCL source RS for more than one CSI-RSs for beam management, the UE determines that an RS of the current beam to measure for event based beam reporting is an SSB that is a QCL source RS, such as a QCL-D source RS, for the TRS.

[0030] If the UE determines at 170 that the TRS is not a QCL source RS for more than one CSI-RSs for beam management, the UE determines that an RS of the current beam to measure for event based beam reporting is a CSI-RS for beam management for which the TRS is a QCL (e g. QCL-D) source RS.

[0031] In alternate embodiments to steps 150, 160 and 170, the UE may instead determine, in FIGURE 2 at 250, from a TRS configuration that the TRS of the current indicated TCI state is transmitted using a CSI-RS for beam management. Based on this determination, the UE may determine at 260 that an RS of the current beam to measure for event based beam reporting to be the CSI-RS for beam management for which the TRS is a QCL (e.g. QCL-D) source.

[0032] In yet further alternate embodiments to 150, 160 and 170, the UE may instead determine, in FIGURE 3 at 350, from a CSI-RS configuration for beam management that a CSI- RS configured for beam management and its QCL (e.g. QCL-D) source RS represent, or are comprised in, a same beam. Based on this determination, the UE may determine at 360 an RS of the current beam to measure for event based beam reporting to be the CSI-RS configured for beam management for which the TRS is a QCL (e.g. QCL-D) source.

[0033] The same logic described above for determining an RS of the current beam to measure for event based beam reporting can also be used for determining new beams from active TCI states and / or configured TCI states where TRS is a QCL (e.g. QCL-D) source RS.

[0034] Figure 4 depicts a block diagram illustrating an example wireless apparatus (400) in accordance with embodiments of the invention. The wireless apparatus may include at least one processor (420), at least one memory (410) coupled to the at least one processor (420) and at least one suitable transceiver (430, 431) having a transmitter and a receiver coupled to the at least one processor (420), coupled to at least one antenna unit (450, 451) through at least one amplifier (440, 441). The at least one memory (410) may store computer programs, which may, when executed by the at least one processor (420), for example in combination with any of the at least one transceiver (430, 431), at least one amplifier (440, 441) and at least one antenna unit(450, 451), perform embodiments of the invention. For example, a user equipment, such as a mobile phone, car, watch or drone may be embodied in apparatus 400.

[0035] Embodiments of the invention may be implemented in software (executed by one or more processors), hardware (e.g., an application specific integrated circuit or field programmable gate array), or a combination of software and hardware. In an example embodiment, the software (e.g., application logic, an instruction set) is maintained on any one of various conventional non-transitory computer-readable media.

[0036] The software, hardware, or combination thereof, or the apparatus 400 or parts thereof, may provide means for performing embodiments of the invention.

[0037] Although various aspects are set out above, other aspects comprise other combinations of features from the described embodiments, and not solely the combinations described above.

Claims

CLAIMS1. A method for a user equipment, comprising: receiving a configuration for event based beam reporting; receiving a configuration activation of one or more TCI states; receiving an indication designating an activated TCI as a current indicated TCI state; determining that a quasi co located (QCL) source reference signal (RS) of the current indicated TCI state is a tracking reference signal (TRS); determining whether the TRS is a QCL source RS for more than one channel state information RSs (CSLRSs); and in response to determining that the TRS is a QCL source RS for more than one CSLRSs, selecting a synchronization signal / physical broadcast channel block (SSB) that is a QCL source RS for the TRS as RS for measurement for event based beam reporting.

2. The method of claim 1, further comprising: in response to determining that the TRS is not a QCL source RS for more than one CSLRSs, selecting a beam management CSLRS of which the TRS is a QCL source RS for measurement for event based beam reporting.

3. A method for a user equipment, comprising: receiving a configuration for event based beam reporting; receiving a configuration activation of one or more TCI states; receiving an indication designating an activated TCI as a current indicated TCI state; determining that a quasi co located (QCL) source reference signal (RS) of the current indicated TCI state is a tracking reference signal (TRS); in response to determining that the QCL source RS of the current indicated TCI state is a TRS, establishing from a configuration of the TRS that the TRS is transmitted using a channel state information RS (CSLRS) configured for beam manament; andin response to the establishing, selecting the CSI-RS configured for beam management, of which the TRS is a QCL source RS, as RS for measurement for event based beam reporting.

4. A method for a user equipment, comprising: receiving a configuration for event based beam reporting; receiving a configuration activation of one or more TCI states; receiving an indication designating an activated TCI as a current indicated TCI state; determining that a quasi co located (QCL) source reference signal (RS) of the current indicated TCI state is a tracking reference signal (TRS); in response to determining that the QCL source RS of the current indicated TCI state is a TRS, establishing from a channel state information RS (CSLRS) configuration for beam management that a CSLRS configured for beam management and a TRS of the current indicated TCI state represent a same beam; and in response to the establishing, selecting the CSLRS configured for beam management, of which the TRS is a QCL source RS, as RS for measurement for event based beam reporting.

5. The method of any of claims 1-4, wherein the QCL source RS is a QCL-D source RS as defined in 3 GPP NR.

6. The method of any of claims 1-5, wherein the event based beam reporting comprising user equipment initiated beam reporting.

7. The method of any of claims 1 -6, wherein the event based beam reporting is triggered when a physical layer reference signal receiver power (Ll-RSRP) of a beam becomes a threshold value better than a Ll-RSRP measured on the selected RS for measurement for event based beam reporting.

8. An apparatus, comprising: at least one processor; and at least one memory including computer program code the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to at least: receive a configuration for event based beam reporting; receive a configuration activation of one or more TCI states; receive an indication designating an activated TCI as a current indicated TCI state; determine that a quasi co located (QCL) source reference signal (RS) of the current indicated TCI state is a tracking reference signal (TRS); determine whether the TRS is a QCL source RS for more than one channel state information RSs (CSLRSs); and in response to determining that the TRS is a QCL source RS for more than one CSLRSs, select a synchronization signal / physical broadcast channel block (SSB) that is a QCL source RS for the TRS as RS for measurement for event based beam reporting.

9. The apparatus of claim 1, wherein the apparatus further caused to at least: in response to determining that the TRS is not a QCL source RS for more than one CSLRSs, select a beam management CSLRS of which the TRS is a QCL source RS for measurement for event based beam reporting.

10. An apparatus, comprising: at least one processor; and at least one memory including computer program code the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to at least: receive a configuration for event based beam reporting; receive a configuration activation of one or more TCI states; receive an indication designating an activated TCI as a current indicated TCI state; determine that a quasi co located (QCL) source reference signal (RS) of the current indicated TCI state is a tracking reference signal (TRS);in response to determining that the QCL source RS of the current indicated TCI state is a TRS, establish from a configuration of the TRS that the TRS is transmitted using a channel state information RS (CSI-RS) configured for beam manament; and in response to the establishing, select the CSI-RS configured for beam management, of which the TRS is a QCL source RS, as RS for measurement for event based beam reporting.

11. An apparatus, comprising: at least one processor; and at least one memory including computer program code the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to at least: receive a configuration for event based beam reporting; receive a configuration activation of one or more TCI states; receive an indication designating an activated TCI as a current indicated TCI state; determine that a quasi co located (QCL) source reference signal (RS) of the current indicated TCI state is a tracking reference signal (TRS); in response to determining that the QCL source RS of the current indicated TCI state is a TRS, establish from a channel state information RS (CSI-RS) configuration for beam management that a CSI-RS configured for beam management and a TRS of the current indicated TCI state represent a same beam; and in response to the establish, select the CSI-RS configured for beam management, of which the TRS is a QCL source RS, as RS for measurement for event based beam reporting.

12. The apparatus of any of claims 8-11, wherein the QCL source RS is a QCL-D source RS as defined in 3 GPP NR.

13. The apparatus of any of claims 8-12, wherein the event based beam reporting comprising user equipment initiated beam reporting.

14. The apparatus of any of claims 8-13, wherein the event based beam reporting is triggered when a physical layer reference signal receiver power (Ll-RSRP) of a beam becomes a threshold value better than a Ll-RSRP measured on the selected RS for measurement for event based beam reporting.

15. A computer program, which when executed by at least one processor, causes an apparatus at least to peform: the method of any of claims 1-7;16. A non-transitory computer-readable medium encoded with instructions that, when executed by at least one processor, cause an apparatus to perform the method according to any of claims 1 -7.

17. An apparatus (400) comprising means for performing the method of any of claims 1-7.

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