Patent Description:
3GPP Tdoc Rl-<NUM> reiterates that, following a current RRC structure for aperiodic CSI trigger states, each trigger state contains one or multiple report settings, CSI-AssociatedReportConfigInfo, and the maximum number of report settings to be associated with one trigger state could be maxNrofReportConfigPerAperiodicTrigger = <NUM>. The number of configured trigger states could be maxNrOfCSI-AperiodicTriggers = <NUM>.

Advantageous embodiments are subject to the dependent claims.

Aspects of the present disclosure provide apparatus, methods, processing systems, and computer readable mediums for a user equipment (UE) indication of a number of supported trigger states.

In certain systems, such as new radio (e.g., <NUM> NR) systems, aperiodic channel state information reference signals (A-CSI-RS) are transmitted by the base station (BS). The UE uses the A-CSI-RS for CSI reporting. The BS configures the UE with one or more resource sets for the A-CSI-RS. The resource sets may include the same or different A-CSI-RS resources. The BS also configures the UE with aperiodic trigger states. Each trigger state triggers at least one of the configured A-CSI-RS resource sets. The BS also downselects the number of active trigger states from the configured trigger states. In some examples, the BS can configure the UE with <NUM> aperiodic trigger states and the BS may downselect to up to <NUM> active aperiodic trigger states (of the <NUM> configured). The BS may send downlink control information (DCI) indicating one or more of the active aperiodic trigger states.

For the same A-CSI-RS resource in the same resource set, the transmission configuration indicator (TCI) state (e.g., beam) may be different for different trigger states. Thus, different trigger states, including those that trigger one or more of the same A-CSI-RS resources, may be associated with different TCI states. Because the total number of active trigger states is determined by the BS (e.g., up to <NUM> active trigger states) with the same A-CSI-RS potentially having different TCI states for each trigger states, the UE may track (e.g., time and frequency tracking) many TCI states (e.g., up to <NUM> TCI states) for the same A-CSI-RS resource for dynamic beam indication/beam switch. In some examples, the UE may track the many TCI states simultaneously (e.g., at the same time, concurrently, or during an overlapping period of time). In this case, the UE may reserve memory for DCI based beam switch within up to all of the possible active beams (e.g., <NUM>).

Therefore, what is needed are techniques for the UE to indicate its supported number of trigger states. Accordingly, aspects of the present disclose provide techniques for the UE to indicate its capability for the number of activated or configured aperiodic trigger states. The indicated number may be less than a total number of trigger states. The UE may provide the indication as UE capability information. In one example, the UE may provide the indication via radio resource control (RRC) or medium access control control element (MAC-CE) signaling. In one aspect, the UE may provide the indication per trigger type. In a further example, the UE may provide additional information to the BS associated with the supported number of trigger states.

The following description provides examples of a UE indication of supported trigger states, and is not limiting of the scope, applicability, or examples set forth in the claims.

The techniques described herein may be used for various wireless networks and radio technologies. For clarity, while aspects may be described herein using terminology commonly associated with <NUM> wireless technologies, aspects of the present disclosure can be applied in other generation-based communication systems, such as later releases and technologies.

Certain wireless networks utilize orthogonal frequency division multiplexing (OFDM) on the downlink (and/or uplink) and single-carrier frequency division multiplexing (SC-FDM) on the uplink.

In NR, an RB may be <NUM> consecutive frequency subcarriers. The cyclic prefix (CP) length also depends on the subcarrier spacing. In NR, a subframe is <NUM>, but the basic transmission time interval (TTI) may be referred to as a slot.

NR access (e.g., <NUM> NR) may support various wireless communication services, such as enhanced mobile broadband (eMBB) targeting wide bandwidth (e.g., <NUM> or beyond), millimeter wave (mmW) targeting high carrier frequency (e.g., <NUM> or beyond), massive machine type communications MTC (mMTC) targeting non-backward compatible MTC techniques, and/or mission critical targeting ultra-reliable low-latency communications (URLLC).

For example, the wireless communication network <NUM> may be an NR system (e.g., <NUM> NR network).

As illustrated in <FIG>, the wireless communication network <NUM> may include a number of BSs 110a-z (each also individually referred to herein as BS <NUM> or collectively as BSs <NUM>) and other network entities. A BS <NUM> may provide communication coverage for a particular geographic area, sometimes referred to as a "cell", which may be stationary or may move according to the location of a mobile BS. In some examples, the BSs <NUM> may be interconnected to one another and/or to one or more other BSs or network nodes (not shown) in wireless communication network <NUM> through various types of backhaul interface (e.g., a direct physical connection, a wireless connection, a virtual network, or the like) using any suitable transport network. The BSs <NUM> communicate with UEs 120a-y (each also individually referred to herein as UE <NUM> or collectively as UEs <NUM>) in the wireless communication network <NUM>.

As shown in <FIG>, a UE 120a in the wireless communication network <NUM> includes a trigger state manager <NUM>. The trigger state manager <NUM> may be configured to provide an indication to a BS 110a in the wireless communication network <NUM> of a number of aperiodic trigger states supported by the UE 120a. The trigger state manager <NUM> may be configured to receive a configuration or activation of one or more aperiodic trigger states from the BS 110a in accordance with the indication. As shown in <FIG>, a BS 110a in the wireless communication network <NUM> includes a trigger state manager <NUM>. The trigger state manager <NUM> may be configured to receive an indication from the UE 120a in the wireless communication network <NUM> of a number of aperiodic trigger states supported by the UE 120a. The trigger state manager <NUM> may be configured to provide the UE 120a a configuration or activation of one or more aperiodic trigger states in accordance with the indication.

Wireless communication network <NUM> may also include relay stations (e.g., relay station 110r), also referred to as relays or the like, that receive a transmission of data and/or other information from an upstream station (e.g., the BS 110a or the UE 120r) and sends a transmission of the data and/or other information to a downstream station (e.g., a UE <NUM> or a BS <NUM>), or that relays transmissions between UEs <NUM>, to facilitate communication between devices.

<FIG> illustrates example components of a BS and a UE, such as the BS 110a and UE 120a in the wireless communication network <NUM>, which may be used to implement aspects of the present disclosure.

At the BS 110a, a transmit processor <NUM> may receive data from a data source <NUM> and control information from a controller/processor <NUM>. The processor <NUM> may also generate reference symbols, such as for the primary synchronization signal (PSS), secondary synchronization signal (SSS), and cell-specific reference signal (CRS). A transmit (TX) multiple-input multiple-output (MIMO) processor <NUM> may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, and/or the reference symbols, if applicable, and may provide output symbol streams to the modulators (MODs) 232a-432t. Downlink signals from modulators 232a-232t may be transmitted via the antennas 234a-434t, respectively.

At the UE 120a, the antennas 252a-452r may receive the downlink signals from the BS 110a and may provide received signals to the demodulators (DEMODs) in transceivers 254a-254r, respectively. A MIMO detector <NUM> may obtain received symbols from all the demodulators 254a-254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor <NUM> may process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for the UE 120a to a data sink <NUM>, and provide decoded control information to a controller/processor <NUM>.

On the uplink, at UE 120a, a transmit processor <NUM> may receive and process data (e.g., for the physical uplink shared channel (PUSCH)) from a data source <NUM> and control information (e.g., for the physical uplink control channel (PUCCH) from the controller/processor <NUM>. The symbols from the transmit processor <NUM> may be precoded by a TX MIMO processor <NUM> if applicable, further processed by the demodulators in transceivers 254a through 254r (e.g., for SC-FDM, etc.), and transmitted to the BS 110a. At the BS 110a, the uplink signals from the UE 120a may be received by the antennas <NUM>, processed by the modulators <NUM>, detected by a MIMO detector <NUM> if applicable, and further processed by a receive processor <NUM> to obtain decoded data and control information sent by the UE 120a.

The controllers/processors <NUM> and <NUM> may direct the operation at the BS 110a and the UE 120a, respectively. The processor <NUM> and/or other processors and modules at the BS 110a may perform or direct the execution of processes for the techniques described herein. For example, as shown in <FIG>, the controller/processor <NUM> of the UE 120a includes a trigger state manager <NUM> that may be configured for a UE indication of supported number of trigger states, in accordance with certain aspects of the present disclosure. As shown, the controller/processor <NUM> of the BS 110a includes a trigger state manager <NUM> that may be configured for a UE indication of supported number of trigger states, in accordance with certain aspects of the present disclosure.

As discussed above, aspects of the present disclosure relate to an indication of UE supported number of trigger states. In certain systems (e.g., <NUM> NR systems), a user equipment (UE) is configured with uplink and downlink resources. For example, the UE may be configured with uplink resources for sounding reference signal (SRS) transmission (e.g., aperiodic SRS), physical uplink control channel (PUCCH) transmission, and/or physical uplink shared channel (PUSCH) transmission. The UE may be configured with downlink resources for physical downlink control channel (PDCCH) transmission, physical downlink shared channel (PDSCH) transmission, and/or channel state information (CSI) reference signals (RS), such as aperiodic CSI-RS (A-CSI-RS).

In some examples, the base station (BS) configures the UE with one or more resource sets for A-CSI-RS. The A-CSI-RS may be used by the UE for CSI reporting. For example, the UE can measure the A-CSI-RS to report CSI to the BS. The BS may configure the A-CSI-RS resource sets via higher layer signaling, such as radio resource control (RRC) signaling. The BS configures the UE with trigger states for triggering the configured A-CSI-RS resource sets. Each trigger state may configure at least one A-CSI-RS resource set. In some examples, the UE is configured with up to <NUM> aperiodic trigger states. In some cases, the BS may down select, or activate, a subset of up to <NUM> active trigger states, for example, via RRC or a medium access control (MAC) control element (CE). The BS may select the number of the subset trigger states, such <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> trigger states.

The trigger states may be indicated via downlink control information (DCI). For example, the subset of trigger state may be mapped to DCI codepoints (e.g., via the RRC or MAC CE signaling) and the DCI can then select one or more of the trigger states to be used. The UE may monitor and measure A-CSI-RS from the BS and provide a CSI report to the BS, based on the A-CSI-RS resource set(s) associated with the selected trigger states. For the same A-CSI-RS resource in the same resource set, the transmission configuration indicator (TCI) state may be different for different trigger states. A-CSI-RS may update a spatial relation for other uplink resources, such as A-SRS, PUCCH, and/or PUSCH. A-CSI-RS may update quasi-colocation (QCL) information for other downlink resources, such as another A-CSI-RS, PDCCH, and/or PDSCH. In some examples, a given A-CSI-RS resource can be transmitted via up to <NUM> different beams.

Because the total number of active trigger states is determined by the BS (e.g., up to <NUM> active trigger states) with the same A-CSI-RS potentially having different TCI states for each trigger states, the UE may need to track (e.g., time and frequency tracking) many different TCI states (e.g., up to <NUM> TCI states) for the same A-CSI-RS resource for dynamic beam indication/beam switch. In some examples, the UE may track the many TCI states simultaneously (e.g., at the same time, concurrently, or during an overlapping period of time). In this case, the UE may reserve memory for DCI based beam switch within up to <NUM> possible active beams.

Therefore, what is needed are techniques for the UE to indicate its supported number of trigger states. Accordingly, aspects of the present disclose provide techniques for the UE to indicate its capability for the number of activated or configured aperiodic trigger states.

<FIG> is a call flow <NUM> illustrating an example indication of the UE capability of the supported number of active trigger states. As shown in <FIG>, at <NUM>, the UE <NUM> can send the BS <NUM> an indication of the supported number of trigger states. For example, the UE <NUM> sends an indication of the maximum number of active A-CSI-RS trigger states that the UE supports (e.g., or a requested number of active A-CSI-RS trigger states). At <NUM>, the UE <NUM> is configured with a set of trigger states, for example, via higher layer RRC signaling. In some examples, the configured set of trigger states takes into account the number of supported trigger states indicated at <NUM> (e.g., is equal to less than the indicated number). At <NUM>, the UE <NUM> may receive signaling activating a subset of the configured trigger states, for example, via lower layer signaling such as MAC-CE, or via RRC. In some examples, the configured set of trigger states takes into account the number of supported trigger states indicated at <NUM> (e.g., is equal to less than the indicated number). Although the UE indication of the supported number of trigger states at <NUM> is shown in <FIG> as before the configuration of the trigger states, in other examples, the UE indication could be provided after the configuration but before the activation at <NUM>. At <NUM>, the UE <NUM> may receive DCI from the BS <NUM> trigger one or more A-CSI-RS resource set(s), for example, by indicating/selecting one or more trigger states, of the activated subset of trigger states, associated with the one or more A-CSI-RS resource sets. The triggered A-CSI-RS resource sets may be used by the UE <NUM> and BS <NUM> for the A-CSI-RS and CSI reporting at <NUM> and <NUM>, respectively.

<FIG> is a flow diagram illustrating example operations <NUM> for wireless communication, in accordance with certain aspects of the present disclosure. The operations <NUM> may be performed, for example, by a UE (e.g., such as a UE 120a in the wireless communication network <NUM>). Operations <NUM> may be implemented as software components that are executed and run on one or more processors (e.g., controller/processor <NUM> of <FIG>). Further, the transmission and reception of signals by the UE in operations <NUM> may be enabled, for example, by one or more antennas (e.g., antennas <NUM> of <FIG>). In certain aspects, the transmission and/or reception of signals by the UE may be implemented via a bus interface of one or more processors (e.g., controller/processor <NUM>) obtaining and/or outputting signals.

The operations <NUM> may begin, at <NUM>, by providing an indication to a BS of a number of aperiodic trigger states supported by the UE. In some examples, the number is equal to or less than <NUM> (e.g., <NUM>, <NUM>, <NUM>, <NUM>. In some examples, the UE indicates a maximum number of active aperiodic trigger states supported by the UE. In some examples, the UE indicates a maximum number of configured aperiodic trigger states supported by the UE. Each aperiodic trigger state may trigger transmission of at least one A-CSI-RS resource set (e.g., when selected/indicated in a DCI).

In some examples, the UE provides the indication with UE capability information (e.g., as part of capability exchange). In some examples, the UE provides the indication via RRC signaling or a MAC-CE.

According to the invention, the UE provides the indication of the maximum number of aperiodic trigger states per trigger type. For example, the UE may provide the indication (e.g., only) for trigger states triggering A-CSI-RS to update QCL information and/or to update a spatial relation for other resources. In this case, the BS only limits the configuration or activation of this type of trigger state to within the indicated maximum number.

According to certain aspects, the UE may provide another indication of other aspects associated with the triggers. In some example, the other indication may be provided with the indication of the UE capability of the number of support aperiodic trigger states. In some examples, the other indication is provided for each trigger state or for all of the trigger states. In some examples, the other indication indicates a maximum number of supported report configurations per aperiodic trigger state (e.g., <NUM>); a maximum number of total triggered A-CSI-RS resources; a maximum number of A-CSI-RS resources per resource set; and/or a maximum number of TCI states per A-CSI-RS resource or for all A-CSI-RS resources triggered by different active aperiodic trigger states, such as a maximum number of distinct QCL TypeD RS in TCI states.

A TCI state may indicate a quasi-co-location (QCL) relation/assumption. QCL assumptions generally refer to assumptions that, for a set of signals or channels considered to be QCL related (QCL'd), certain characteristics derived for (measured from) one of the signals or channels may be applied to the other. An antenna port is defined such that the channel over which a symbol on the antenna port is conveyed can be inferred from the channel over which another symbol on the same antenna port is conveyed. Two antenna ports are said to be QCL'd if properties of the channel over which a symbol on one antenna port is conveyed can be inferred from the channel over which a symbol on the other antenna port is conveyed. The QCL assumptions may be grouped into different types that correspond to the parameters that may be assumed QCL'd for a set of QCL'd signals. For example, for a set of QCL'd signals, Type A may indicate that Doppler shift, Doppler spread, average delay, delay spread can be assumed QCL'd, while Type B may indicate only Doppler shift and Doppler spread, Type C may indicate a still different set of parameters. In some cases, spatial QCL assumptions may be indicated, for example, by Type D. Spatial QCL may mean a (Tx or Rx) beam selected based on a certain signal measurement may be applied to the QCL related signal.

At <NUM>, the UE receives an activation of one or more aperiodic trigger states from the BS in accordance with the indication. For example, the BS may limit the number of activated aperiodic trigger states based on the indicated UE capability (e.g., activates equal or less than the number of trigger states supported by the UE).

In some examples, the UE receives a configuration of aperiodic trigger states from the BS in accordance with the indication, as shown in <FIG>at <NUM> and <NUM>. For example, the BS may limit the number of configured aperiodic trigger states based on the indicated UE capability (e.g., configures equal or less than the number of trigger states supported by the UE).

<FIG> is a flow diagram illustrating example operations <NUM> for wireless communication, in accordance with certain aspects of the present disclosure. The operations <NUM> may be performed, for example, by a BS (e.g., such as a BS 110a in the wireless communication network <NUM>). The operations <NUM> may be complimentary operations by the BS to the operations <NUM> performed by the UE. Operations <NUM> may be implemented as software components that are executed and run on one or more processors (e.g., controller/processor <NUM> of <FIG>). Further, the transmission and reception of signals by the BS in operations <NUM> may be enabled, for example, by one or more antennas (e.g., antennas <NUM> of <FIG>). In certain aspects, the transmission and/or reception of signals by the BS may be implemented via a bus interface of one or more processors (e.g., controller/processor <NUM>) obtaining and/or outputting signals.

The operations <NUM> may begin, at <NUM>, by receiving an indication from a UE of a number of aperiodic trigger states (e.g., a maximum number of configured or activated) supported by the UE. In some examples, the indication is received with UE capability information. The indication may be received via RRC signaling or a MAC-CE.

At <NUM>, the BS provides an activation of one or more aperiodic trigger states to the UE in accordance with the indication. In some examples, the BS activates a number of aperiodic trigger states equal to less than the indicated maximum number of activated aperiodic trigger states supported by the UE. In some examples, the BS activates equal to or less than an indicated number of supported trigger states per trigger type.

According to the invention, the BS provides a configuration of aperiodic trigger states from the BS in accordance with the indication, as shown in <FIG>at <NUM> and <NUM>. In some examples, the BS configures a number of aperiodic trigger states equal to less than the indicated maximum number of configured aperiodic trigger states supported by the UE. In some examples, the BS configures equal to or less than an indicated number of supported trigger states per trigger type.

<FIG> illustrates a communications device <NUM> that may include various components (e.g., corresponding to means-plus-function components) configured to perform operations for the techniques disclosed herein, such as the operations illustrated in <FIG> and/or <FIG>.

The processing system <NUM> includes a processor <NUM> coupled to a computer-readable medium/memory <NUM> via a bus <NUM>. In certain aspects, the computer-readable medium/memory <NUM> is configured to store instructions (e.g., computer-executable code) that when executed by the processor <NUM>, cause the processor <NUM> to perform the operations illustrated in <FIG> and/or <FIG>, or other operations for performing the various techniques discussed herein for a UE indication of the UE capability for the maximum number of supported trigger states. In certain aspects, computer-readable medium/memory <NUM> stores code <NUM> for providing an indication of the number of supported aperiodic trigger states by a UE and code <NUM> for receiving a configuration or activation of one or more aperiodic trigger states in accordance with the indication. In certain aspects, the processor <NUM> has circuitry configured to implement the code stored in the computer-readable medium/memory <NUM>. The processor <NUM> includes circuitry <NUM> for providing an indication of the number of supported aperiodic trigger states by a UE and circuitry <NUM> for receiving a configuration or activation of one or more aperiodic trigger states in accordance with the indication.

The processing system <NUM> includes a processor <NUM> coupled to a computer-readable medium/memory <NUM> via a bus <NUM>. In certain aspects, the computer-readable medium/memory <NUM> is configured to store instructions (e.g., computer-executable code) that when executed by the processor <NUM>, cause the processor <NUM> to perform the operations illustrated in <FIG> and/or <FIG>, or other operations for performing the various techniques discussed herein for a UE indication of the UE capability for the maximum number of supported trigger states. In certain aspects, computer-readable medium/memory <NUM> stores code <NUM> for receiving an indication of the number of supported aperiodic trigger states by a UE and code <NUM> for providing a configuration or activation of one or more aperiodic trigger states in accordance with the indication. In certain aspects, the processor <NUM> has circuitry configured to implement the code stored in the computer-readable medium/memory <NUM>. The processor <NUM> includes circuitry <NUM> for providing an indication of the number of supported aperiodic trigger states by a UE and circuitry <NUM> for providing a configuration or activation of one or more aperiodic trigger states in accordance with the indication.

Claim 1:
A method for wireless communications by a user equipment, UE, comprising:
providing (<NUM>), to a base station, BS, an indication of a number of aperiodic trigger states supported by the UE, wherein the indication of the number of aperiodic trigger states includes an indication of a number of supported aperiodic trigger states per trigger type for a plurality of trigger types; and
receiving (<NUM>), from the BS, an activation or a configuration of one or more aperiodic trigger states in accordance with the indication of the number of aperiodic trigger states.