Wireless communication method executed by UE (user equipment) and network entity, UE and network entity

Abstract

The present disclosure provides methods and apparatus for determining whether a channel state information reference signal (CSI-RS) is to be transmitted based on results of listen before talk (LBT) operations in a plurality of sub-bands of a broadband, and for transmission of CSI-RS on the broadband. In one aspect, a method of wireless communication performed by an apparatus of a user equipment, UE, includes receiving configuration information for a channel state information reference signal, CSI-RS, where the configuration information indicates that the CSI-RS is configured on a plurality of subbands; receiving information indicating availability of a plurality of sub-bands for the CSI-RS; selectively receiving the CSI-RS on the basis of the configuration information and on the basis of availability of a plurality of sub-bands for the CSI-RS, in which the CSI-RS is received when all of the plurality of sub-bands are available for the CSI-RS, and the CSI-RS is not received when at least one of the plurality of sub-bands is not available for the CSI-RS; and if the CSI-RS is received, transmitting channel state information (CSI) feedback based on the configuration information.

Description

[0001] This application is a divisional application of the invention patent application with application number 202080050182.7 filed on July 13, 2020 and invention name “Channel State Information Reference Signal for Wideband Operation”. CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims priority to Indian Patent Application No. 201941028335, filed on July 15, 2019, entitled “CHANNEL STATE INFORMATION REFERENCE SIGNAL FOR WIDEBAND OPERATION” and U.S. Non-Provisional Patent Application No. 16 / 946,901, filed on July 10, 2020, entitled “CHANNEL STATE INFORMATION REFERENCE SIGNAL FOR WIDEBAND OPERATION,” which are hereby expressly incorporated herein by reference. Technical Field

[0003] Aspects of the present disclosure relate generally to wireless communications and techniques for channel state information (CSI) reference signals (RS) for wideband operation in unlicensed spectrum. Background Art

[0004] Wireless communication systems are widely deployed to provide a variety of telecommunication services, such as telephony, video, data, messaging, and broadcasting. Typical wireless communication systems may employ multiple access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc.). Examples of such multiple access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems, as well as Long Term Evolution (LTE). LTE / LTE-Advanced is a collection of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP).

[0005] A wireless communication network may include multiple base stations (BSs) that can support communications for multiple user equipment (UEs). User equipment (UEs) may communicate with a base station (BS) via a downlink and an uplink. DL (or forward link) refers to a communication link from a BS to a UE, and an uplink (or reverse link) refers to a communication link from a UE to a BS. As will be described in more detail herein, a BS may be referred to as a NodeB, an LTE evolved nodeB (eNB), a gNB, an access point (AP), a radio head, a transmit receive point (TRP), a new radio (NR) base station, a 5G NodeB, or further examples.

[0006] The above-mentioned multiple access technologies have been used in various telecommunication standards to provide a common protocol that enables different UEs to communicate at a city, country, region, or even global level. NR, which may also be referred to as 5G, is a collection of enhancements to the LTE mobile standard promulgated by the 3rd Generation Partnership Project (3GPP). NR is designed to better support mobile broadband Internet access by improving spectrum efficiency, reducing costs, improving services, utilizing new spectrum, and better integrating with other open standards that use orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the DL, CP-OFDM and / or SC-FDM (e.g., also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)) on the UL (or a combination thereof), and support beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation. Summary of the invention

[0007] The systems, methods and devices of the present disclosure each have several innovative aspects, no single one of which is solely responsible for the desirable attributes disclosed herein.

[0008] One innovative aspect of the subject matter described in the present disclosure may be implemented in a method of wireless communication performed by a user equipment (UE). The method may include: receiving configuration information for a channel state information reference signal (CSI-RS), wherein the configuration information indicates that the CSI-RS is configured on multiple subbands of a wideband structure; selectively receiving the CSI-RS based on the configuration information and based on subband validity indications associated with the multiple subbands; and sending channel state information (CSI) feedback based on the configuration information if the CSI-RS is received.

[0009] In some implementations, the method may include receiving downlink control information indicating a subband valid indication.

[0010] In some implementations, when all subbands of the plurality of subbands are available for CSI-RS, the CSI-RS is received, and when at least one subband of the plurality of subbands is not available for CSI-RS, the CSI-RS is not received.

[0011] In some implementations, the method may include rate matching the shared channel around the resources of the CSI-RS regardless of whether the CSI-RS is received.

[0012] In some implementations, the method may include performing processing operations associated with CSI-RS with respect to multiple subbands regardless of whether the CSI-RS is received.

[0013] In some implementations, the method may include: determining that a CSI-RS will be received based on subband usage information received before resources associated with the CSI-RS; and performing processing operations associated with the CSI-RS regarding multiple subbands based on determining that the CSI-RS will be received.

[0014] In some implementations, the CSI-RS is received on a subband subset of the plurality of subbands based on the subband subset being available for the CSI-RS.

[0015] In some implementations, the sequence for CSI-RS for multiple subbands is punctured to generate CSI-RS for a subset of subbands.

[0016] In some implementations, the CSI-RS for a subset of subbands is generated based on a shortened sequence relative to a sequence used for the CSI-RS for multiple subbands.

[0017] In some implementations, the method may include receiving a trigger for CSI feedback based on all subbands in the plurality of subbands being available for CSI-RS.

[0018] In some implementations, when the CSI-RS is received on a subband subset of a plurality of subbands, the CSI-RS is received on a resource element corresponding to the widest bandwidth of the wideband structure on the subband subset.

[0019] In some implementations, the CSI-RS is generated based on the same sequence for the widest bandwidth and for a subset of subbands.

[0020] In some implementations, the CSI-RS spans 48 resource blocks in the subbands of the subband subset.

[0021] In some implementations, the resource elements intersect with resource elements of the broadband structure.

[0022] In some implementations, the method may include receiving a trigger for CSI feedback after indicating COT-SI for a subset of subbands in a plurality of subbands available for CSI-RS.

[0023] In some implementations, CSI-RS is used for periodic or semi-persistent CSI feedback.

[0024] In some implementations, CSI-RS is used for aperiodic CSI feedback.

[0025] In some implementations, the method may include rate matching a shared channel around resources of the CSI-RS based on a plurality of subbands being available for the CSI-RS.

[0026] In some implementations, the method may include selectively receiving the CSI-RS based on at least one of: COT-SI received prior to the resource of the CSI-RS, a signal-to-noise ratio associated with the resource of the CSI-RS, or a value associated with a grant for a shared channel.

[0027] In some implementations, the method may include performing processing operations associated with the CSI-RS for the plurality of subbands based on the COT-SI received after receiving the CSI-RS.

[0028] In some implementations, the method may include performing per-subband processing operations associated with the CSI-RS to determine per-subband CSI feedback; and identifying a subband subset of a plurality of subbands on which to receive the CSI-RS, wherein the CSI feedback is based on the per-subband CSI feedback associated with the subband subset.

[0029] In some implementations, the method may include receiving a grant for a subband subset of the plurality of subbands; and rate matching a shared channel associated with the grant around resources associated with a CSI-RS on the subband subset.

[0030] In some implementations, the method may include receiving a grant for a subband subset of a plurality of subbands; and rate matching a shared channel associated with the grant around resources associated with the CSI-RS on the subband subset based on receiving a COT-SI prior to the CSI-RS, wherein the COT-SI indicates that the subband subset is available.

[0031] In some implementations, CSI-RS is received on a subset of subbands.

[0032] In some implementations, the configuration information includes configurations for a plurality of different subband subsets of the plurality of subbands.

[0033] In some implementations, the method may include receiving a trigger associated with configuration for a particular subband subset of a plurality of different subband subsets based on the particular subband subset being available for the CSI-RS.

[0034] In some implementations, the method may include receiving a trigger indicating a particular subband subset among a plurality of different subband subsets based on the particular subband subset being available for the CSI-RS.

[0035] In some implementations, the power level of the CSI-RS per resource element or per subband is independent of the number of subbands on which the CSI-RS is transmitted.

[0036] In some implementations, the power level of the CSI-RS per resource element or per subband is based on the number or configuration of subbands on which the CSI-RS is transmitted.

[0037] In some implementations, the power level of the CSI-RS is based on whether the CSI-RS is aperiodic, periodic, or semi-persistent.

[0038] In some implementations, the method may include determining a power level of the CSI-RS based on at least one of: a number or configuration of subbands on which the CSI-RS is transmitted, or information indicating a power level of the CSI-RS.

[0039] Another innovative aspect of the subject matter described in the present disclosure may be implemented in an apparatus of a UE for wireless communication. The apparatus may include a first interface configured to: obtain configuration information for a CSI-RS, wherein the configuration information indicates that the CSI-RS is configured on multiple subbands of a wideband structure; and selectively obtain the CSI-RS based on the configuration information and based on subband valid indications associated with the multiple subbands; and a second interface configured to: if the CSI-RS is obtained, send CSI feedback based on the configuration information.

[0040] Another innovative aspect of the subject matter described in the present disclosure may be implemented in a non-transitory computer-readable medium. The non-transitory computer-readable medium may store one or more instructions for wireless communication. When executed by one or more processors of a UE, the one or more instructions may cause the one or more processors to: receive configuration information for a CSI-RS, wherein the configuration information indicates that the CSI-RS is configured on multiple subbands of a broadband structure; selectively send the CSI-RS based on the configuration information and based on subband valid indications associated with the multiple subbands; and if the CSI-RS is received, send CSI feedback based on the configuration information.

[0041] Another innovative aspect of the subject matter described in the present disclosure can be implemented in an apparatus for wireless communication. The apparatus may include: a component for sending configuration information for a CSI-RS, wherein the configuration information indicates that the CSI-RS is configured on multiple subbands of a wideband structure; and a component for selectively sending the CSI-RS based on the configuration information and based on subband valid indications associated with the multiple subbands; and a component for sending CSI feedback based on the configuration information if the CSI-RS is received.

[0042] Another innovative aspect of the subject matter described in the present disclosure may be implemented in a method of wireless communication performed by an apparatus of a base station (BS). The method may include: transmitting configuration information for a CSI-RS, wherein the configuration information indicates a plurality of subbands of a wideband structure for the CSI-RS; performing a listen-before-talk (LBT) operation to identify a subband subset of a plurality of subbands that can be used for the CSI-RS, wherein the subband subset includes at most all of the plurality of subbands; and selectively transmitting the CSI-RS based on a result of the LBT operation.

[0043] In some implementations, when all subbands of the plurality of subbands are available for CSI-RS, the CSI-RS is transmitted, and when at least one subband of the plurality of subbands is not available for CSI-RS, the CSI-RS is not transmitted.

[0044] In some implementations, the method may include rate matching the shared channel around the resources of the CSI-RS regardless of whether the CSI-RS is transmitted.

[0045] In some implementations, the subset of subbands includes less than all subbands of the plurality of subbands.

[0046] In some implementations, the sequence for CSI-RS for multiple subbands is punctured to generate CSI-RS for a subset of subbands.

[0047] In some implementations, the CSI-RS for a subset of subbands is generated based on a shortened sequence relative to a sequence used for the CSI-RS for multiple subbands.

[0048] In some implementations, the method may include sending a trigger for CSI feedback associated with the CSI-RS based on all subbands in the plurality of subbands being available for the CSI-RS.

[0049] In some implementations, when the CSI-RS is transmitted on a subband subset of a plurality of subbands, the CSI-RS is transmitted on a resource element corresponding to the widest bandwidth of the wideband structure on the subband subset.

[0050] In some implementations, the CSI-RS is based on the same sequence for the widest bandwidth and for a subset of subbands.

[0051] In some implementations, the CSI-RS spans 48 resource blocks in the subbands of the subband subset.

[0052] In some implementations, the resource elements intersect with resource elements of the broadband structure.

[0053] In some implementations, CSI-RS is used for periodic or semi-persistent CSI feedback.

[0054] In some implementations, CSI-RS is used for aperiodic CSI feedback.

[0055] In some implementations, the method may include rate matching a shared channel around resources of the CSI-RS based on a plurality of subbands being available for the CSI-RS.

[0056] In some implementations, the method may include sending subband usage information identifying the subband subset, wherein the subband usage information identifying the subband subset is associated with at least one of: a COT-SI sent prior to a resource of a CSI-RS, a value associated with a grant for a shared channel, or downlink control information indicating the subband subset.

[0057] In some implementations, the method may include sending a grant for a subband subset; and rate matching a shared channel associated with the grant around resources associated with a CSI-RS on the subband subset.

[0058] In some implementations, the method may include sending a grant for a subband subset; sending a COT-SI before a CSI-RS; and rate matching a shared channel associated with the grant around resources associated with the CSI-RS on the subband subset based on sending the COT-SI before the CSI-RS.

[0059] In some implementations, the method may include sending a trigger for CSI feedback associated with the CSI-RS after indicating the COT-SI for a subset of subbands in the plurality of subbands available for the CSI-RS.

[0060] In some implementations, the configuration information includes configurations for a plurality of different subband subsets of the plurality of subbands.

[0061] In some implementations, the method may include sending a trigger associated with configuration for a particular subband subset among a plurality of different subband subsets based on the particular subband subset being available for the CSI-RS.

[0062] In some implementations, the method may include sending a trigger indicating a particular subband subset among a plurality of different subband subsets based on the particular subband subset being available for the CSI-RS.

[0063] In some implementations, the power level of the CSI-RS per resource element or per subband is independent of the number of subbands on which the CSI-RS is transmitted.

[0064] In some implementations, the power level of the CSI-RS per resource element or per subband is based on the number or configuration of subbands on which the CSI-RS is transmitted.

[0065] In some implementations, the power level of the CSI-RS per resource element or per subband is based on whether the CSI-RS is aperiodic, periodic, or semi-persistent.

[0066] In some implementations, the method may include determining a power level of the CSI-RS based on at least one of: a number or configuration of subbands on which the CSI-RS is transmitted, or information indicating a power level of the CSI-RS.

[0067] In some implementations, the CSI-RS is sent when the COT-SI associated with the CSI-RS can be sent before the CSI-RS, and wherein the CSI-RS is not sent when the COT-SI associated with the CSI-RS cannot be sent before the CSI-RS.

[0068] Another innovative aspect of the subject matter described in the present disclosure can be implemented in an apparatus of a BS for wireless communication. The apparatus may include a first interface configured to: output configuration information for a CSI-RS, wherein the configuration information indicates a plurality of subbands of a broadband structure for the CSI-RS; and a processing system configured to: perform a listen-before-talk (LBT) operation to identify a subband subset of a plurality of subbands that can be used for the CSI-RS, wherein the subband subset includes at most all of the plurality of subbands, wherein the first interface is further configured to: selectively output the CSI-RS based on a result of the LBT operation.

[0069] Another innovative aspect of the subject matter described in the present disclosure may be implemented in a non-transitory computer-readable medium. The non-transitory computer-readable medium may store one or more instructions for wireless communication. When executed by one or more processors of a BS, the one or more instructions may cause the one or more processors to: send configuration information for a CSI-RS, wherein the configuration information indicates a plurality of subbands of a broadband structure for the CSI-RS; perform a listen-before-talk (LBT) operation to identify a subband subset of a plurality of subbands that can be used for the CSI-RS, wherein the subband subset includes at most all subbands of the plurality of subbands; and selectively send the CSI-RS based on the result of the LBT operation.

[0070] Another innovative aspect of the subject matter described in the present disclosure can be implemented in an apparatus for wireless communication. The apparatus may include: a component for sending configuration information for a CSI-RS, wherein the configuration information indicates a plurality of subbands of a wideband structure for the CSI-RS; a component for performing a listen-before-talk (LBT) operation to identify a subband subset of a plurality of subbands that can be used for the CSI-RS, wherein the subband subset includes at most all of the plurality of subbands; and a component for selectively sending the CSI-RS based on a result of the LBT operation.

[0071] As fully described with reference to and as illustrated in the accompanying drawings, aspects generally include a method, an apparatus, a system, a computer program product, a non-transitory computer readable medium, a user equipment, a base station, a wireless communication device, or a processing system.

[0072] Details of one or more implementations of the subject matter described in the present disclosure are set forth in the accompanying drawings and the following description. Other features, aspects, and advantages will become apparent from the description, drawings, and claims. Note that the relative sizes of the following drawings may not be drawn to scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 is a block diagram conceptually illustrating an example of a wireless network.

[0074] Figure 2 is a block diagram conceptually illustrating an example of a base station (BS) communicating with a user equipment (UE) in a wireless network.

[0075] Figure 3 is a diagram illustrating an example of a wideband channel state information reference signal (CSI-RS) configuration for periodic or semi-persistent CSI-RS.

[0076] Figure 4 is a diagram illustrating an example of a wideband CSI-RS configuration for an aperiodic CSI-RS.

[0077] Figure 5is a diagram illustrating an example of a CSI-RS configuration in which a CSI-RS is transmitted on an available subband and not on an unavailable subband.

[0078] Figure 6 is a diagram illustrating an example of a CSI-RS configuration in which the CSI-RS is not transmitted when any subband is unavailable.

[0079] Figure 7 is a diagram illustrating an example of resource element selection for wideband CSI-RS.

[0080] Figure 8 is a diagram illustrating an example process performed, for example, by a UE.

[0081] Fig. 9 is a diagram illustrating an example process performed, for example, by a BS.

[0082] Like reference numbers and designations in the various drawings indicate like elements. DETAILED DESCRIPTION

[0083] The following description is directed to certain implementations for the purpose of describing the innovative aspects of the present disclosure. However, one of ordinary skill in the art will readily recognize that the teachings herein may be applied in a variety of different ways. Some of the examples in the present disclosure are based on wireless and wired local area network (LAN) communications in accordance with the Institute of Electrical and Electronics Engineers (IEEE) 802.11 wireless standard, the IEEE 802.3 Ethernet standard, and the IEEE 1901 Power Line Communication (PLC) standard. However, the described implementations may be implemented in any device, system, or network capable of sending and receiving radio frequency signals in accordance with any of the wireless communication standards, including any of the following: the IEEE 802.11 standard, the Bluetooth standard, the IEEE 802.3 standard, the IEEE 1901 Power Line Communication (PLC) standard, and the IEEE 1901 Power Line Communication (PLC) standard. ® Standard, Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Global System for Mobile Communications (GSM), GSM / General Packet Radio Service (GPRS), Enhanced Data GSM Environment (EDGE), Terrestrial Trunked Radio (TETRA), Wideband CDMA (W-CDMA), Evolution-Data Optimized (EV-DO), 1xEV-DO, EV-DO Rev A, EV-DO Rev B, High Speed ​​Packet Access (HSPA), High Speed ​​Downlink Packet Access (HSDPA), High Speed ​​Uplink Packet Access (HSUPA), Evolved High Speed ​​Packet Access (HSPA+), Long Term Evolution (LTE), AMPS or other known signals used to communicate within a wireless, cellular or Internet of Things (IoT) network, such as utilizing 3G, 4G or 5G or further implementations or technologies thereof.

[0084] Certain radio access technologies (RATs) such as NR may allow operation in unlicensed spectrum. NR RATs for unlicensed spectrum may be referred to as NR-Unlicensed (NR-U or NRU). Certain RATs may support different bandwidths for subbands or subband combinations, such as 20 MHz, 40 MHz, 60 MHz, 80 MHz, or further examples. For example, multiple 20 MHz subbands may be combined to form a larger bandwidth, referred to as a wideband. The combination of multiple subbands may be referred to herein as a wideband structure. A wideband structure may be a bandwidth portion of a UE (i.e., a configured bandwidth of a UE in which the UE may communicate on one or more subbands).

[0085] If a UE is configured with multiple subbands in an unlicensed spectrum, not all of the subbands may be available at all times. For example, certain subbands may be occupied by other UEs, base stations, wireless nodes, or further examples. The base station or UE may perform a listen-before-talk (LBT) operation to determine whether one or more subbands are available for communication. In an LBT operation, a base station or UE may listen to a channel or subband for a period of time, and if no other reservations for the channel or subband are received while the base station or UE is listening, or if the interference on the channel or subband meets a threshold, an indication may then be sent that the base station or UE has reserved the channel or subband for the time window. Thus, coexistence between devices on non-centrally scheduled channels, such as sidelink channels on unlicensed spectrum, is enabled.

[0086] A base station may use channel state information (CSI) feedback to determine channel conditions for a channel between the base station and the UE. For example, a base station may send a CSI-RS to one or more UEs, the CSI-RS having certain characteristics that are available to or determinable by the UE. Using the CSI-RS, the UE may determine CSI feedback, such as a CSI report, that indicates the channel conditions between the base station and the UE. However, in the case of an unlicensed spectrum with a wideband structure, not all subbands configured for the CSI-RS may be available when the CSI-RS is to be sent. In addition, the UE may or may not have received information indicating which subbands are available when the CSI-RS is to be sent (because this information may sometimes be after the CSI-RS). Certain operations, such as rate matching around the CSI-RS and the transmission or processing of the CSI-RS itself, may be hampered by this uncertainty.

[0087] The techniques and apparatus described herein provide a determination of whether a CSI-RS will be transmitted based on the results of an LBT operation on a subband of a wideband structure, and a configuration for the transmission of CSI-RS on a wideband structure. For example, certain techniques and apparatus described herein provide signaling of subband usage information indicating which subbands are available before a CSI-RS is transmitted, thereby allowing a UE to determine whether a CSI-RS will be transmitted, and if so, on which subbands. In addition, certain techniques and apparatus described herein provide rate matching configuration based on whether subband usage has been received, based on which subbands are available, or further examples. Further, certain techniques and apparatus described herein provide power configuration and resource element selection criteria for wideband CSI-RS and CSI feedback.

[0088] Specific implementations of the subject matter described in the present disclosure may be implemented to achieve one or more of the following potential advantages. By determining which subbands will contain CSI-RS, and by determining the power configuration of the CSI-RS, the use of CSI-RS over a wideband may be improved. Certain implementations may improve resource utilization by providing a subband-specific rate matching configuration rather than an "all-or-nothing" approach in which CSI-RS is rate matched across the entire wideband or not matched at all. Certain implementations may reduce complexity by providing an all-or-nothing approach for rate matching CSI-RS. In addition, certain implementations may improve resource utilization by ensuring that subband usage information is provided to the UE before the CSI-RS, which may reduce uncertainty in unlicensed bands and may save UE resources that would otherwise be used to process non-existent CSI-RS. This may ensure that the UE estimates and reports accurate channel estimates / channel quality indications to the base station so that the base station can configure DL / UL communication parameters and resources (such as modulation schemes, coding rates, spatial multiplexing / diversity, etc.). For example, if the UE incorrectly assumes the presence of CSI-RS in a subband, the UE may send erroneous CSI feedback / reports, which may cause the BS to configure communication parameters that are suboptimal and result in performance degradation.

[0089] Figure 11 is a block diagram conceptually illustrating an example of a wireless network 100. The wireless network 100 may be an LTE network or some other wireless network, such as a 5G or NR network. The wireless network 100 may include a plurality of BSs 110 (shown as BSs 110a, BSs 110b, BSs 110c, and BSs 110d) and other network entities. A BS is an entity that communicates with a user equipment (UE) and may also be referred to as a base station, an NR BS, a Node B, a gNB, a 5G Node B (NB), an access point, a transmit receive point (TRP), or further examples. Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term "cell" may refer to a coverage area of ​​a BS, a BS subsystem serving this coverage area, or a combination thereof, depending on the context in which the term "cell" is used.

[0090] A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, another type of cell, or a combination thereof. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscriptions. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscriptions. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs associated with the femto cell (e.g., UEs in a closed subscriber group (CSG)). A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In Figure 1 In the example shown, BS 110a may be a macro BS for macro cell 102a, BS 110b may be a pico BS for pico cell 102b, and BS 110c may be a femto BS for femto cell 102c. A BS may support one or more (e.g., three) cells. The terms "eNB", "base station", "NR BS", "gNB", "TRP", "AP", "Node B", "5G NB", and "cell" may be used interchangeably herein.

[0091] In some examples, the cell may not necessarily be fixed, and the geographical area of ​​the cell may move according to the location of the mobile BS. In some examples, the BSs may be interconnected with each other and with one or more other BSs or network nodes (not shown) in the wireless network 100 through various types of backhaul interfaces (such as direct physical connections, virtual networks, or combinations thereof) using any suitable transport network.

[0092] The wireless network 100 may also include a relay station. A relay station is an entity that can receive transmissions of data from an upstream station (e.g., a BS or a UE) and send transmissions of data to a downstream station (e.g., a UE or a BS). A relay station may also be a UE that can relay transmissions for other UEs. Figure 1 In the example shown, a relay station 110d may communicate with a macro BS 110a and a UE 120d to facilitate communication between the BS 110a and the UE 120d. A relay station may also be referred to as a relay BS, a relay base station, a relay, or the like.

[0093] The wireless network 100 may be a heterogeneous network including different types of BSs (e.g., macro BSs, pico BSs, femto BSs, relay BSs, etc.). These different types of BSs may have different transmit power levels, different coverage areas, and different effects on interference in the wireless network 100. For example, a macro BS may have a high transmit power level (e.g., 5 to 40 watts), while a pico BS, a femto BS, and a relay BS may have a lower transmit power level (e.g., 0.1 to 2 watts).

[0094] A network controller 130 may be coupled to a set of BSs and may provide coordination and control for these BSs. The network controller 130 may communicate with the BSs via a backhaul. The BSs may also communicate with each other directly or indirectly, for example, via a wireless or wired backhaul.

[0095] UE 120 (e.g., 120a, 120b, 120c) can be dispersed throughout the wireless network 100, and each UE can be fixed or mobile. UE can also be referred to as an access terminal, terminal, mobile station, subscriber unit, station, etc. UE can be a cellular phone (e.g., a smart phone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, a biometric sensor / device, a wearable device (smart watch, smart clothing, smart glasses, smart wristband, smart jewelry (e.g., smart ring, smart bracelet)), an entertainment device (e.g., a music or video device, or a satellite radio), a vehicle-mounted component or sensor, a smart meter / sensor, an industrial manufacturing device, a global positioning system device, or any other suitable device configured to communicate via a wireless or wired medium.

[0096] Some UEs may be considered as machine type communication (MTC) UEs, or evolved or enhanced machine type communication (eMTC) UEs. MTC UEs and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc. that can communicate with a base station, another device (e.g., a remote device), or some other entity. A wireless node may provide connectivity, for example, for or to a network (e.g., a wide area network such as the Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered as Internet of Things (IoT) devices, and / or may be implemented as NB-IoT (narrowband Internet of Things) devices. Some UEs may be considered as customer premises equipment (CPE). UE 120 may be included in a housing that houses components of UE 120 (such as a processor component, a memory component, a similar component, or a combination thereof).

[0097] Generally speaking, any number of wireless networks can be deployed in a given geographic area. Each wireless network can support a specific RAT and can operate on one or more frequencies. RAT can also be referred to as radio technology, air interface, etc. Frequency can also be referred to as carrier, frequency channel, etc. Each frequency can support a single RAT in a given geographic area to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks can be deployed.

[0098] In some examples, access to the air interface may be scheduled, wherein a scheduling entity (e.g., a base station) allocates resources for communication between some or all devices and equipment within a service area or cell of the scheduling entity. Within the present disclosure, as discussed further below, a scheduling entity may be responsible for scheduling, assigning, reconfiguring, and releasing resources for one or more subordinate entities. That is, for scheduled communications, the subordinate entities utilize resources allocated by the scheduling entity.

[0099] The base station is not the only entity that can be used as a scheduling entity. That is, in some examples, the UE can be used as a scheduling entity, scheduling resources for one or more subordinate entities (e.g., one or more other UEs). In this example, the UE acts as a scheduling entity, and other UEs use the resources scheduled by the UE for wireless communication. The UE can be used as a scheduling entity in a peer-to-peer (P2P) network, a mesh network, or another type of network. In the mesh network example, in addition to communicating with the scheduling entity, the UEs can optionally communicate directly with each other.

[0100] Thus, in a wireless communication network having scheduled access to time-frequency resources and having a cellular configuration, a P2P configuration, and a mesh configuration, a scheduling entity and one or more slave entities may communicate using the scheduled resources.

[0101] In some aspects, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) may communicate directly (e.g., without using base station 110 as an intermediary to communicate with each other) using one or more side link channels. For example, UE 120 may communicate using peer-to-peer (P2P) communication, device-to-device (D2D) communication, vehicle-to-everything (V2X) protocol (which may include vehicle-to-vehicle (V2V) protocol, vehicle-to-infrastructure (V2I) protocol, or similar protocol), mesh network or similar network, or a combination thereof. In this case, UE 120 may perform scheduling operations, resource selection operations, and other operations described elsewhere herein as being performed by base station 110.

[0102] Figure 2 1 is a block diagram conceptually illustrating an example 200 of a base station (BS) communicating with a user equipment (UE) 120 in a wireless network. In some aspects, the base station 110 and the UE 120 may be Figure 1 One of the base stations and one of the UEs in the wireless network 100. The base station 110 may be equipped with T antennas 234a through 234t, and the UE 120 may be equipped with R antennas 254a through 254r, where in general T≥1 and R≥1.

[0103] At the base station 110, the transmit processor 220 may receive data for one or more UEs from the data source 212, select one or more modulation and coding schemes (MCS) for each UE based on a channel quality indicator (CQI) received from the UE, process (e.g., encode and modulate) the data for each UE based on the (one or more) MCS selected for each UE, and provide data symbols for all UEs. The transmit processor 220 may also process system information (e.g., for semi-static resource partitioning information (SRPI) and the like) and control information (e.g., CQI requests, grants, upper layer signaling, etc.) and provide overhead symbols and control symbols. The transmit processor 220 may also generate reference symbols for reference signals (e.g., cell-specific reference signals (CRS)) and synchronization signals (e.g., primary synchronization signals (PSS) and secondary synchronization signals (SSS)). The transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on ​​data symbols, control symbols, overhead symbols, and / or reference symbols, where applicable, and may provide T output symbol streams to T modulators (MOD) 232a to 232t. Each modulator 232 may process a corresponding output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator 232 may further process the output sample stream (e.g., convert to analog, amplify, filter, and upconvert) to obtain a downlink signal. T downlink signals from modulators 232a to 232t may be transmitted via T antennas 234a to 234t, respectively. According to various aspects described in more detail below, position coding may be used to generate synchronization signals to convey additional information.

[0104] At UE 120, antennas 252a to 252r may receive downlink signals from base station 110 or other base stations, and may provide received signals to demodulators (DEMOD) 254a to 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) the received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. A MIMO detector 256 may obtain received symbols from all R demodulators 254a to 254r, perform MIMO detection on the received symbols where applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE 120 to a data sink 260, and provide decoded control information and system information to a controller or processor (controller / processor) 280. The channel processor may determine reference signal received power (RSRP), received signal strength indicator (RSSI), reference signal received quality (RSRQ), channel quality indicator (CQI), etc. In some aspects, one or more components of UE 120 may be included in a housing.

[0105] On the uplink, at the UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information from a controller / processor 280 (e.g., for reports including RSRP, RSSI, RSRQ, CQI, etc.). The transmit processor 264 may also generate reference symbols for one or more reference signals. The symbols from the transmit processor 264 may be precoded by a TX MIMO processor 266, if applicable, further processed by demodulators 254a through 254r (e.g., for DFT-s-OFDM, CP-OFDM, etc.), and transmitted to the base station 110. At the base station 110, uplink signals from the UE 120 and other UEs may be received by the antenna 234, processed by the demodulator 232, detected by the MIMO detector 236, if applicable, and further processed by the receive processor 238 to obtain decoded data and control information transmitted by the UE 120. The receive processor 238 may provide the decoded data to a data sink 239 and provide the decoded control information to a controller or processor (i.e., controller / processor) 240. The base station 110 may include a communication unit 244 and communicate with the network controller 130 via the communication unit 244. The network controller 130 may include a communication unit 294, a controller or processor (i.e., controller / processor) 290, and a memory 292.

[0106] In some implementations, the controller / processor 280 may be a component of a processing system. A processing system may generally refer to a system or series of machines or components that receives input and processes the input to produce a set of outputs that may be delivered to other systems or components, such as the UE 120. For example, a processing system of the UE 120 may refer to a system that includes various other components or subcomponents of the UE 120.

[0107] The processing system of UE 120 may interface with other components of UE 120, and may process information (such as input or signal) received from other components, output information to other components, etc. For example, a chip or modem of UE 120 may include a processing system, a first interface for receiving or obtaining information, and a second interface for outputting, sending, or providing information. In some cases, the first interface may refer to an interface between a processing system of a chip or modem and a receiver, so that UE 120 may receive information or signal input, and the information may be passed to the processing system. In some cases, the second interface may refer to an interface between a processing system of a chip or modem and a transmitter, so that UE 120 may send information output from the chip or modem. A person of ordinary skill in the art will readily recognize that the second interface may also obtain or receive information or signal input, and the first interface may also output, send, or provide information.

[0108] In some implementations, controller / processor 240 may be a component of a processing system. A processing system may generally refer to a system or series of machines or components that receives inputs and processes the inputs to produce a set of outputs that may be delivered to other systems or components, such as BS 110. For example, a processing system of BS 110 may refer to a system that includes various other components or subcomponents of BS 110.

[0109] The processing system of BS 110 may interface with other components of BS 110, and may process information (such as input or signal) received from other components, output information to other components, etc. For example, a chip or modem of BS 110 may include a processing system, a first interface for receiving or obtaining information, and a second interface for outputting, sending, or providing information. In some cases, the first interface may refer to an interface between a processing system of the chip or modem and a receiver, so that BS 110 may receive information or signal input, and the information may be passed to the processing system. In some cases, the second interface may refer to an interface between a processing system of the chip or modem and a transmitter, so that BS 110 may send information output from the chip or modem. One of ordinary skill in the art will readily recognize that the second interface may also obtain or receive information or signal input, and the first interface may also output, send, or provide information.

[0110] The controller / processor 240 of the base station 110, the controller / processor 280 of the UE 120, or Figure 2 Any other component(s) of the controller / processor 240 of the base station 110, the controller / processor 280 of the UE 120, or the like may perform one or more techniques associated with CSI-RS for wideband operation, as described in more detail elsewhere herein. For example, the controller / processor 240 of the base station 110, the controller / processor 280 of the UE 120, or the like Figure 2 Any other component(s) (or combination of components) may perform or direct e.g. Figure 8 The process of 800 Fig. 9 The operations of process 900, or other processes as described herein. Memories 242 and 282 may store data and program codes for base station 110 and UE 120, respectively. Scheduler 246 may schedule UEs for data transmission on the downlink, uplink, or a combination thereof.

[0111] The stored program code, when executed by the controller / processor 280 or other processors and modules at the UE 120, may cause the UE 120 to perform operations related to Figure 8 The stored program code, when executed by the controller / processor 240 or other processors and modules at the base station 110, may cause the base station 110 to perform operations related to Fig. 9 The operations described by process 900 or other processes described herein. The scheduler 246 can schedule UEs for data transmission on the downlink, uplink, or a combination thereof.

[0112] UE 120 may include a processor for performing one or more operations described herein (such as Figure 8 In some aspects, such components may include a combination of Figure 2 The base station 110 may include one or more components of the UE 120 described herein. The base station 110 may include a Fig. 9 In some aspects, such components may include a combination of Figure 2 One or more components of base station 110 are described.

[0113] Although Figure 2 The blocks in the 200 and 210 are shown as distinct components, but the functionality described above with respect to these blocks may be implemented in a single hardware, software, or combined component or in various combinations of components. For example, the functionality described with respect to the transmit processor 264, the receive processor 258, the TX MIMO processor 266, or another processor may be performed by or under the control of the controller / processor 280.

[0114] Figure 3 is a diagram illustrating an example 300 of a wideband channel state information (CSI) reference signal (RS) configuration for periodic or semi-persistent CSI-RS. Figure 3 includes a single UE 120 and a single BS 110, but in combination Figure 3 The operations described may be performed by any two or more wireless nodes.In addition, BS 110 may perform the operations described herein for a group of UEs 120, such as UEs 120 communicating with BS 110.

[0115] As shown at reference numeral 310, BS 110 may send configuration information. For example, the configuration information may identify a CSI-RS configuration such as for a periodic CSI-RS (P-CSI-RS) or a semi-persistent CSI-RS (SP-CSI-RS). In some aspects, the CSI-RS may be an aperiodic CSI-RS (A-CSI-RS) that is combined with Figure 4 120 , such as a bandwidth portion configuration of the UE 120. In some aspects, the configuration information may include information indicating a power scaling configuration for the CSI-RS, which is described in more detail below.

[0116] In some aspects, UE 120 may receive a grant for a shared channel, such as a physical downlink shared channel (PDSCH). The grant may be received on one or more subbands that may be available for CSI-RS, since BS 110 may not grant resources on unavailable subbands. Thus, UE 120 may determine which subbands are available subbands based on the grant. UE 120 may rate match the shared channel around the CSI-RS resources, as described in more detail below.

[0117] As shown in reference numeral 320, BS 110 may perform an LBT operation on a subband group. For example, BS 110 may perform an LBT operation on a subband on which a CSI-RS is configured before transmitting the CSI-RS. BS 110 may determine an LBT result for each subband in the subband group. The LBT result may indicate whether the corresponding subband can be used for CSI-RS or other communications performed by BS 110. The subband on which LBT is performed may also be referred to as an RB set or an LBT bandwidth. For example, the LBT result for a subband may indicate that the subband is associated with an interference level that meets a threshold (ie, is below a threshold), or that the subband is not associated with another reservation of a time window associated with the CSI-RS. As an example, at an antenna of BS 110, the threshold for the interference level may be approximately -82 decibel milliwatts (dBm). The time window for the LBT operation may be referred to as a transmit opportunity. BS 110 may provide a subband validity indication indicating the LBT result to UE 120. For example, BS 110 may provide the subband validity indication via DCI, medium access control signaling, etc. The subband validity indication may include information indicating one or more subbands that are valid (or invalid) for communication. For example, based at least in part on a channel access operation (such as based at least in part on an LBT result associated with the channel access operation), the subband validity indication may include a bitmap indicating subbands, LBT bandwidths, or RB sets on which communications are valid.

[0118] In some cases, not all subbands in a subband group may be available for CSI-RS, as indicated by reference numeral 330. In this case, BS 110 may drop or not transmit CSI-RS, or may perform CSI-RS transmission on available subbands.

[0119] In some aspects, when at least one subband in the subband group is not available for CSI-RS, the BS 110 may not send CSI-RS. This may be referred to herein as an "all or nothing" approach. In the all or nothing approach, the BS 110 may send CSI-RS when all subbands of the subband group are available for CSI-RS. This may save signaling resources that would otherwise be used to configure or send partial CSI-RS using less than all subbands of the subband group, and may reduce the complexity of a particular design implementation. Second, in the all or nothing approach, if the CSI-RS is not sent in a valid subband (because another subband is not available), the CSI-RS resources may be used for data so that the data does not need to be rate matched around the CSI-RS resources.

[0120] In some aspects, BS 110 may transmit CSI-RS on available subbands of a subband group. For example, when one subband is unavailable and three subbands are available for CSI-RS, BS 110 may transmit CSI-RS on three subbands but not on one unavailable subband. This may enable CSI-RS to be provided on partially available resources, which may improve network utilization efficiency relative to an all-or-nothing approach.

[0121] In some aspects, the BS 110 may use a sequence to generate a CSI-RS. In some aspects, when the CSI-RS is transmitted on a subband subset of a band group, the BS 110 may modify the sequence. As a first example, the BS 110 may truncate the sequence for the subband group to generate a sequence for the subband subset. In this case, if subbands 0, 2, and 3 are available for CSI-RS and subband 1 is unavailable, the BS 110 may truncate the sequence for subbands 0, 1, 2, and 3 at a position corresponding to subband 1 in the sequence, and may generate the CSI-RS using the truncated sequence. As used herein, truncation of a sequence may refer to discarding one or more values ​​of a sequence corresponding to an unavailable subband. For example, if a sequence includes 80 values ​​and the second subband of the four subbands associated with the sequence is unavailable, the BS 110 may discard the twenty-first to fortieth values ​​of the sequence, may use a zero value or a default value for these values, or further examples. As a second example, BS110 may use a shortened sequence based on the number of resource elements of the CSI-RS. In this example, if the sequence includes 80 values ​​and the second subband of the four subbands associated with the sequence is unavailable, BS 110 may generate the CSI-RS using a 60-symbol sequence. In the case of a shortened sequence, UE 120 may determine subband usage information (using a channel occupancy time (COT) structure indicator (SI), an indication based on a grant, or a further example) before the CSI-RS so that UE 120 may determine the length of the shortened sequence. In some aspects, UE 120 may determine a truncated sequence (such as by performing per-subband processing of the CSI-RS to determine which subbands are used for the CSI-RS) without determining or receiving subband usage information, which may simplify processing at UE 120.

[0122] As indicated by reference numeral 340, BS 110 may send subband usage information, shown here as a channel occupancy time (COT) structure indicator (SI). In some aspects, the subband usage information may be sent in another form, such as downlink control information (DCI) indicating subband usage, aperiodic CSI-RS triggering, PDSCH grant, physical uplink shared channel grant, or further examples. COT-SI may indicate which subbands in a subband group may be used for CSI-RS. For example, COT-SI may indicate LBT results for a subband group. In some aspects, UE 120 may receive COT-SI in a control channel, such as a physical downlink control channel (PDCCH).

[0123] In some cases, COT-SI may be sent before CSI-RS. In such cases, UE 120 may determine which subbands will be used for CSI-RS, or whether CSI-RS will be sent, before the transmission time of CSI-RS. In some aspects, if COT-SI is received before the transmission time of CSI-RS, UE 120 may determine that CSI-RS is present in the transmission opportunity. If UE 120 does not receive COT-SI before the transmission time of CSI-RS, UE 120 may determine that no CSI-RS is expected in the transmission opportunity. In this case, if BS 110 cannot send COT-SI before the transmission time of CSI-RS, BS 110 may not send CSI-RS. This may save UE resources that would otherwise be used to store CSI-RS while waiting for COT-SI.

[0124] In some aspects, COT-SI may be sent after CSI-RS. In this case, UE 120 may not know which subbands will be used for CSI-RS until after CSI-RS is received. In some aspects, UE 120 may store CSI-RS and may process CSI-RS after receiving COT-SI. For example, UE 120 may delay processing of CSI-RS until after COT-SI is received. In this case, UE 120 may process the latest CSI-RS even if COT-SI is not available (such as based on COT-SI that arrives after CSI-RS).

[0125] As indicated by reference numeral 350, BS 110 may transmit CSI-RS. For example, BS 110 may transmit CSI-RS using available subbands in a subband group. In some aspects, BS 110 may transmit CSI-RS in a downlink (DL) burst, such as a synchronization signal burst. As indicated by reference numeral 360, UE 120 may selectively process CSI-RS. For example, in some aspects, UE 120 may process CSI-RS based on determining that CSI-RS will be transmitted. UE 120 may generate CSI feedback based on processing of CSI-RS.

[0126] In some aspects, the UE 120 may process the CSI-RS based on detecting a DL burst (such as before the COT-SI is received). For example, the UE 120 may process the CSI-RS on each subband of the subband group separately, and may verify the CSI feedback after the COT-SI is received to form a combined CSI feedback for the available subbands. Processing the CSI-RS on each subband separately may be referred to as a per-subband processing operation. Thus, the UE 120 may process the CSI-RS before the COT-SI is received, and may then generate CSI feedback for the available subbands. This may be more reliable than attempting to use measurements on the subbands to identify the subbands on which the CSI-RS is present.

[0127] In some aspects, UE 120 may determine whether CSI-RS is present on a subband based on measurements performed by UE 120. For example, the measurements may be related to a threshold signal-to-noise ratio (SNR) or another threshold. UE 120 may identify which subbands include CSI-RS and may process the CSI-RS on the subbands that include CSI-RS. This may not be as resource intensive as processing the CSI-RS on each subband individually and may not use COT-SI.

[0128] In some aspects, the UE 120 or BS 110 may determine a power level for the CSI-RS. The power level may be based on, for example, a power spectral density (PSD) or a similar value. In some aspects, the power level may be independent of the number of subbands available for the CSI-RS. For example, the power level may be static over time, which may save resources that would otherwise be used to dynamically determine the power level. In some aspects, the power level may be based on the number of subbands available for the CSI-RS. For example, the power level may change over time, which may provide improved CSI-RS performance across different numbers of subbands. In some aspects, the power level may be independent of or dependent on the number of subbands based on whether the CSI is periodic CSI, semi-persistent CSI, or aperiodic CSI.

[0129] In some aspects, the power level may be determined based on the subbands available for CSI-RS. In some aspects, the power level may be explicitly signaled (such as by using a transmit power reduction (TPR) value relative to a nominal power level). In some aspects, the signaling may be included in the COT-SI, or may be included in an aperiodic CSI-RS trigger. In some aspects, the BS 110 may operate on many more subbands than the UE 120, and the COT-SI signaling may be limited to a smaller set of subbands. In this case, explicit signaling of the power level may be beneficial to the BS 110 so that the power level of the CSI-RS can be applied to a smaller set of subbands.

[0130] As indicated by reference numeral 370, in some aspects, the UE 120 may rate match the shared channel around the CSI-RS. For example, if the UE 120 receives a PDSCH grant on a given subband, the subband may be considered available for the CSI-RS because the BS 110 will not grant the PDSCH on an unavailable subband. In some aspects, the UE 120 may rate match the shared channel around the configured resources of the CSI-RS regardless of whether the CSI-RS will be received, which may save resources that would otherwise be used to determine whether the CSI-RS will be received. In some aspects, when the CSI-RS is only transmitted when all subbands are available, the UE 120 may rate match around the CSI-RS when all subbands are available for the CSI-RS. In such cases, if the subband usage information is not received before the CSI-RS, the UE 120 may not decode the PDSCH or may assume that the CSI-RS does not exist. In some aspects, the UE 120 may determine whether the UE 120 has received the CSI-RS based on a measurement, such as an SNR measurement or further example, and may rate match around the CSI-RS if the UE 120 has received the CSI-RS. In some aspects, the PDSCH grant may include an indicator of whether the UE 120 will rate match around a shared channel. For example, the indicator may include a bit indicating whether the UE 120 will rate match around the CSI-RS, which may save resources of the UE 120 that would otherwise be used to determine whether to rate match around a shared channel.

[0131] As indicated by reference numeral 380, UE 120 may selectively send CSI feedback to BS 110. For example, UE 120 may send CSI feedback when UE 120 has determined CSI feedback based on receiving CSI-RS from BS 110. If no CSI-RS is received, or if UE 120 determines that CSI-RS will not be received, UE 120 may not determine or send CSI feedback.

[0132] Figure 4 4 is a diagram illustrating an example 400 of a wideband CSI-RS configuration for an aperiodic CSI-RS. Figure 4 includes a single UE 120 and a single BS 110, but in combination Figure 4 The operations described may be performed by any two or more wireless nodes.In addition, BS 110 may perform the operations described herein for a group of UEs 120, such as several UEs 120 communicating with BS 110.

[0133] As shown in reference numeral 410, BS 110 may send configuration information for aperiodic CSI-RS (sometimes abbreviated as A-CSI-RS). Figure 3 The configuration information is described in more detail. Aperiodic CSI-RS may be associated with aperiodic CSI. As described below, BS 110 may configure one or more aperiodic CSI-RS opportunities for UE 120, and may use a trigger to indicate when UE 120 determines and sends CSI feedback. Unless UE 120 receives a trigger from BS 110, UE 120 may not process CSI-RS or send CSI feedback for CSI-RS resources.

[0134] In some aspects, UE 120 may receive multiple different CSI-RS configurations. For example, UE 120 may receive corresponding CSI-RS configurations for multiple different subband combinations selected from a subband group. In this case, as described below, the trigger may correspond to a CSI-RS configuration to be used (such as a CSI-RS configuration corresponding to a set of available subbands for CSI-RS). As an example, for 4 subbands, there may be 15 CSI-RS configurations.

[0135] As shown in reference numeral 420, BS 110 may perform LBT operations on the subband groups. Figure 3 4. As shown in more detail below. As shown in reference numeral 430, in some cases, not all subbands in the subband group may be available for CSI-RS. In this case, BS 110 may drop or not transmit CSI-RS, or may perform CSI-RS transmission on (one or more) available subbands. When BS 110 determines that CSI-RS transmission will be performed on (one or more) available subbands, BS 110 may send a trigger for CSI-RS, as shown in reference numeral 440.

[0136] In some aspects, BS 110 may send a trigger based on an LBT result indicating that all subbands of a subband group are available. This may save resources that would otherwise be used to provide subband usage information to UE 120, since UE 120 would not receive a trigger unless all subbands are available for CSI-RS.

[0137] In some aspects, the BS 110 may send a trigger when a subset of subbands of a subband group is available. For example, the BS 110 may send a trigger when less than all subbands in a subband group are available for CSI-RS. In some aspects, the BS 110 may send a trigger after sending the subband usage information shown by reference numeral 450, and the UE 120 may use the subband usage information to determine which subbands contain CSI-RS. In this case, the BS 110 may provide a gap between the trigger and the subband usage information sufficient for the UE 120 to decode the subband usage information. This may be based on UE capabilities or other information about the UE 120.

[0138] In some aspects, the trigger may include information indicating which subbands may be used for CSI-RS. For example, the configuration information shown in reference numeral 410 may configure certain CSI-RS parameters, and the trigger may indicate the bandwidth of the CSI-RS, the set of subbands used for the CSI-RS, or further examples. Thus, the BS 110 may use the trigger to indicate which subbands will be used for CSI-RS, which saves resources that would otherwise be used to send COT-SI.

[0139] As shown at reference numeral 460, BS 110 may transmit a CSI-RS. In some aspects, BS 110 may generate a CSI-RS based on a sequence, such as in conjunction with Figure 3 For example, the sequence may be punctured for unavailable subbands, or may be shortened for unavailable subbands, such as in conjunction with Figure 3 As described in more detail.

[0140] As shown at reference numeral 470, UE 120 may selectively process CSI-RS, as described above in conjunction with Figure 3 As shown in more detail in FIG. 3 , UE 120 may rate match the shared channel around the CSI-RS. As shown in FIG. 490 , UE 120 may selectively send CSI feedback to BS 110. These operations are also described in more detail in conjunction with FIG. 3 .

[0141] Figure 55 is a diagram illustrating an example 500 of a CSI-RS configuration in which a CSI-RS is transmitted on available subbands but not on unavailable subbands. As shown, example 500 includes subbands 0 to 3. As further shown, subbands 0, 2, and 3 are available and subband 1 is unavailable. The COT-SI of example 500 is shown by reference numeral 510. The COT-SI may indicate that subbands 0, 2, and 3 are available and subband 1 is unavailable. In some aspects, the COT-SI may be configured to be transmitted before the CSI-RS, as described elsewhere herein. For example, unless the COT-SI is before the CSI-RS, the CSI-RS may not be transmitted, thereby enabling the UE 120 to determine which subbands are available for the CSI-RS. As shown by reference numeral 520, the BS 110 may not transmit the CSI-RS in subband 1. In addition, the BS 110 may transmit the CSI-RS in subbands 0, 2, and 3.

[0142] Figure 6 6 is a diagram illustrating an example 600 of a CSI-RS configuration in which the CSI-RS is not transmitted when any subband is unavailable. Figure 6 As shown, based on the unavailability of subband 1, the CSI-RS is not transmitted on any subband. For example, reference numeral 610 shows that the LBT operation fails in subband 1, while reference numerals 620, 630, and 640 show that the LBT operation is successful in subbands 0, 2, and 3, respectively. Since the LBT operation fails in at least one of the subbands shown in example 600, the CSI-RS is not transmitted on any of the four subbands, as shown by reference numeral 650. This implementation is referred to as an all-or-nothing approach.

[0143] Figure 7 is a diagram illustrating an example 700 of resource element selection for wideband CSI-RS. The transmitter may implement a guard band for the bandwidth, which means that based on regulatory rules, resource elements located at the edge of the bandwidth cannot be used by the transmitter. This can reduce interference and help manage the power spectral density (PSD) of the air interface. The width of the guard band may be based on the bandwidth of the channel. For example, a wider bandwidth may be associated with a wider guard band. In example 700, typically each rectangle corresponds to a subband or a broadband structure consisting of multiple subbands. The guard band is indicated by a dotted line, where the area between the dotted line and the subband edge is the guard band. For example, the guard band for subband 3 is between the dotted line shown in reference numerals 705 and 710 and the corresponding edge of subband 3, while the guard band for the 40 MHz broadband structure formed by subbands 2 and 3 is between the dotted line shown in reference numerals 715 and 720 and the corresponding outer edges of subbands 2 and 3. It can be seen that the guard band for the 40 MHz broadband structure is wider than the guard band for the 20 MHz broadband structure.

[0144] Combination Figure 3-6 The described CSI-RS may be based on a sequence associated with an 80 MHz wideband structure shown in reference numeral 725. More generally, the CSI-RS for a subband group may be based on a sequence associated with the widest bandwidth structure that can be formed using the subband group. However, the guard bands for smaller bandwidths (such as those shown by 705 to 720) may be smaller than the guard bands for the wideband structure 725. This may mean that some resource elements of smaller bandwidths or intermediate bandwidths (such as 40 MHz and 60 MHz) fall outside the available area of ​​the wideband structure, which reduces flexibility and may result in inconsistent transmissions if such resource elements are used for CSI-RS on a wideband structure.

[0145] The BS 110 may use resource elements that can be used for the wideband structure shown by reference numeral 725 regardless of which subband set is actually used for the CSI-RS. In other words, the BS 110 may use resource elements of a subband set that intersect with resource elements of the wideband structure 725, and may truncate resource elements that do not intersect with resource elements of the wideband structure. Figure 7 , the guard bands of the wideband structure 725 are shown by reference numerals 730 and 735. Therefore, the smaller bandwidth subband sets shown by reference numerals 740, 745, 750, 755, 760, 765 and 770 do not use resource elements in the guard bands of the wideband structure. In this configuration, the bandwidth of available resource elements for the 20 MHz bandwidth subband 0 740 is shown by reference numeral 775. It can be seen that the left side of the bandwidth of subband 0 740' ends at the guard band 730 of the wideband structure, rather than at the guard band for the 20 MHz bandwidth. In some examples, such as for a 30 kHz subcarrier spacing, the number of available resource elements for subband 0 can be 48×12 resource elements, or 48 resource blocks. In some other examples, the number of available resource elements for the subband can be 48×12 resource elements, or 48 resource blocks, so that each of the subbands is the same. Similar bandwidth illustrations for 40 MHz bandwidth and 60 MHz bandwidth are shown by reference numerals 780 and 785, respectively. Therefore, by limiting the resource elements of the smaller bandwidth to those that intersect with the resource elements within the available bandwidth of the wideband structure 725, the CSI-RS sequence can be more simply mapped to the smaller bandwidth because the same sequence can be used for a given resource element in both the subband case and the wideband structure case.

[0146] Figure 8 8 is a diagram illustrating an example process 800 performed, for example, by a UE. Process 800 illustrates where a UE, such as UE 120, performs operations associated with CSI feedback for wideband operation.

[0147] like Figure 8 As shown, in some aspects, process 800 may include receiving configuration information for a channel state information reference signal (CSI-RS), wherein the configuration information indicates that the CSI-RS is configured on multiple subbands of a wideband structure (block 810). For example, a UE or an interface of a UE (using antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, controller / processor 280) may receive configuration information for the CSI-RS. The configuration information may indicate that the CSI-RS is configured on multiple subbands of a wideband structure.

[0148] like Figure 8 As shown, in some aspects, process 800 may include selectively receiving CSI-RS based on the configuration information and based on subband valid indications associated with the plurality of subbands (block 820). For example, the UE or an interface of the UE (such as using antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, or controller / processor 280) may selectively receive CSI-RS based on the configuration information and based on subband valid indications associated with the plurality of subbands.

[0149] like Figure 8 As shown, in some aspects, process 800 may include, if CSI-RS is received, sending channel state information (CSI) feedback based on the configuration information (block 830). For example, if CSI-RS is received, the UE or an interface of the UE (using antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, controller / processor 280) may send channel state information (CSI) feedback based on the configuration information.

[0150] Process 800 may include additional aspects, such as any single aspect or any combination of aspects described below or in combination with one or more other processes described elsewhere herein.

[0151] In a first aspect, process 800 may include receiving downlink control information indicating a subband valid indication.

[0152] In a second aspect, alone or in combination with the first aspect, when all subbands of the plurality of subbands are available for the CSI-RS, the CSI-RS is received, and when at least one subband of the plurality of subbands is not available for the CSI-RS, the CSI-RS is not received.

[0153] In a third aspect, alone or in combination with one or more of the first and second aspects, process 800 may include rate matching a shared channel around a resource of a CSI-RS regardless of whether the CSI-RS is received.

[0154] In a fourth aspect, alone or in combination with one or more of the first to third aspects, process 800 may include performing processing operations associated with CSI-RS for multiple subbands regardless of whether the CSI-RS is received.

[0155] In a fifth aspect, alone or in combination with one or more of the first to fourth aspects, process 800 may include determining that a CSI-RS will be received based on subband usage information received before resources associated with the CSI-RS; and based on determining that the CSI-RS will be received, performing processing operations associated with the CSI-RS regarding multiple subbands.

[0156] In a sixth aspect, alone or in combination with one or more of the first to fifth aspects, based on the subband subset being available for the CSI-RS, the CSI-RS is received on a subband subset of the plurality of subbands.

[0157] In a seventh aspect, alone or in combination with one or more of the first to sixth aspects, sequences for CSI-RS for multiple subbands are punctured to generate CSI-RS for a subset of subbands.

[0158] In an eighth aspect, alone or in combination with one or more of the first to seventh aspects, in some implementations, a CSI-RS for a subband subset is generated based on a shortened sequence relative to a sequence used for a CSI-RS for multiple subbands.

[0159] In a ninth aspect, alone or in combination with one or more of the first to eighth aspects, process 800 may include triggering for CSI feedback based on all subbands of a plurality of subbands being available for CSI-RS reception.

[0160] In the tenth aspect, alone or in combination with one or more of the first to ninth aspects, when CSI-RS is received on a subband subset of multiple subbands, the CSI-RS is received on a resource element of the widest bandwidth corresponding to the broadband structure on the subband subset.

[0161] In an eleventh aspect, alone or in combination with one or more of the first to tenth aspects, the CSI-RS is generated based on the same sequence with respect to the widest bandwidth and with respect to the subband subset.

[0162] In a twelfth aspect, alone or in combination with one or more of the first to eleventh aspects, the CSI-RS spans 48 resource blocks in a subband of the subband subset.

[0163] In a thirteenth aspect, alone or in combination with one or more of the first to twelfth aspects, the resource elements intersect with resource elements of the broadband structure.

[0164] In a fourteenth aspect, alone or in combination with one or more of the first to thirteenth aspects, process 800 may include receiving a trigger for CSI feedback after indicating COT-SI for a subset of subbands available for CSI-RS in a plurality of subbands.

[0165] In a fifteenth aspect, alone or in combination with one or more of the first to fourteenth aspects, the CSI-RS is used for periodic or semi-persistent CSI feedback.

[0166] In a sixteenth aspect, alone or in combination with one or more of the first to fifteenth aspects, the CSI-RS is used for aperiodic CSI feedback.

[0167] In a seventeenth aspect, alone or in combination with one or more of the first to sixteenth aspects, process 800 may include rate matching a shared channel around resources of the CSI-RS based on a number of subbands available for the CSI-RS.

[0168] In an eighteenth aspect, alone or in combination with one or more of the first to seventeenth aspects, process 800 may include selectively receiving CSI-RS based on at least one of: COT-SI received prior to the resources of the CSI-RS, a signal-to-noise ratio associated with the resources of the CSI-RS, or a value associated with a grant for a shared channel.

[0169] In a nineteenth aspect, alone or in combination with one or more of the first to eighteenth aspects, process 800 may include performing processing operations associated with CSI-RS regarding multiple subbands based on COT-SI received after receiving the CSI-RS.

[0170] In the twentieth aspect, alone or in combination with one or more of the first to nineteenth aspects, process 800 may include performing per-subband processing operations associated with the CSI-RS to determine per-subband CSI feedback; and identifying a subband subset of a plurality of subbands on which the CSI-RS is received, wherein the CSI feedback is based on the per-subband CSI feedback associated with the subband subset.

[0171] In a twenty-first aspect, alone or in combination with one or more of the first to twentieth aspects, process 800 may include receiving a grant for a subband subset of a plurality of subbands; and rate matching a shared channel associated with the grant around resources associated with a CSI-RS on the subband subset.

[0172] In aspect twenty-second, alone or in combination with one or more of aspects one to twenty-first, process 800 may include receiving a grant for a subband subset of a plurality of subbands; and rate matching a shared channel associated with the grant around resources associated with the CSI-RS on the subband subset based on receiving a COT-SI prior to the CSI-RS, wherein the COT-SI indicates that the subband subset is available.

[0173] In a twenty-third aspect, alone or in combination with one or more of the first to twenty-second aspects, the CSI-RS is received on a subset of subbands.

[0174] In a twenty-fourth aspect, alone or in combination with one or more of the first to twenty-third aspects, the configuration information includes configurations for a plurality of different subband subsets in the plurality of subbands.

[0175] In a twenty-fifth aspect, alone or in combination with one or more of the first to twenty-fourth aspects, process 800 may include receiving a trigger associated with configuration of a particular subband subset among a plurality of different subband subsets based on the particular subband subset being available for CSI-RS.

[0176] In a twenty-sixth aspect, alone or in combination with one or more of the first to twenty-fifth aspects, process 800 may include receiving a trigger indicating a particular subband subset among a plurality of different subband subsets based on the particular subband subset being available for CSI-RS.

[0177] In a twenty-seventh aspect, alone or in combination with one or more of the first to twenty-sixth aspects, the power level of the CSI-RS per resource element or per subband is independent of the number of subbands on which the CSI-RS is transmitted.

[0178] In a twenty-eighth aspect, alone or in combination with one or more of the first to twenty-seventh aspects, the power level of the CSI-RS per resource element or per subband is based on the number or configuration of subbands on which the CSI-RS is transmitted.

[0179] In a twenty-ninth aspect, alone or in combination with one or more of the first to twenty-eighth aspects, the power level of the CSI-RS is based on whether the CSI-RS is aperiodic, periodic, or semi-persistent.

[0180] In a thirtieth aspect, alone or in combination with one or more of the first to twenty-ninth aspects, process 800 may include determining a power level of the CSI-RS based on at least one of: a number or configuration of subbands on which the CSI-RS is transmitted, or information indicating a power level of the CSI-RS.

[0181] Although Figure 8Example blocks of process 800 are shown, but in some aspects, Figure 8 Process 800 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in . Additionally or alternatively, two or more of the blocks of process 800 may be performed in parallel.

[0182] Fig. 9 is a diagram illustrating an example process 900 performed, for example, by a BS. Process 900 illustrates where a base station, such as base station 110, performs operations associated with CSI-RS transmission over a wideband structure.

[0183] like Fig. 9 As shown, in some aspects, process 900 may include sending configuration information for CSI-RS, where the configuration information indicates a plurality of subbands for a wideband structure for CSI-RS (block 910). For example, a base station or an interface of a base station (using controller / processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antenna 234) may send configuration information for CSI-RS. In some aspects, the configuration information indicates a plurality of subbands for a wideband structure for CSI-RS.

[0184] like Fig. 9 As shown, in some aspects, process 900 may include performing a listen-before-talk (LBT) operation to identify a subset of subbands in a plurality of subbands that may be used for CSI-RS, wherein the subset of subbands may include at most all of the plurality of subbands (block 920). For example, a base station or an interface of a base station (using antenna 234, DEMOD 232, MIMO detector 236, receive processor 238, controller / processor 240) may perform an LBT operation to identify a subset of subbands in a plurality of subbands that may be used for CSI-RS. The subset of subbands may include at most all of the plurality of subbands.

[0185] like Fig. 9 As shown, in some aspects, process 900 may include selectively transmitting CSI-RS based on the result of the LBT operation (block 930). For example, as described above, a base station or an interface of a base station (using controller / processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antenna 234) may selectively transmit CSI-RS based on the result of the LBT operation.

[0186] Process 900 may include additional aspects, such as any single aspect or any combination of aspects described below or in combination with one or more other processes described elsewhere herein.

[0187] In the first aspect, when all subbands among a plurality of subbands are available for CSI-RS, CSI-RS is transmitted, and when at least one subband among the plurality of subbands is not available for CSI-RS, CSI-RS is not transmitted.

[0188] In a second aspect, alone or in combination with the first aspect, process 900 can include rate matching a shared channel around a resource of a CSI-RS regardless of whether the CSI-RS is transmitted.

[0189] In a third aspect, alone or in combination with one or more of the first and second aspects, the subband subset includes less than all subbands of the plurality of subbands.

[0190] In a fourth aspect, alone or in combination with one or more of the first to third aspects, sequences for CSI-RS for multiple subbands are punctured to generate CSI-RS for a subset of subbands.

[0191] In a fifth aspect, alone or in combination with one or more of the first to fourth aspects, a CSI-RS for a subband subset is generated based on a shortened sequence relative to a sequence for CSI-RS for multiple subbands.

[0192] In a sixth aspect, alone or in combination with one or more of the first to fifth aspects, process 900 may include a trigger for sending CSI feedback associated with the CSI-RS based on all subbands in a plurality of subbands being available for the CSI-RS.

[0193] In a seventh aspect, alone or in combination with one or more of the first to sixth aspects, when CSI-RS is transmitted on a subband subset of multiple subbands, the CSI-RS is transmitted on a resource element of the widest bandwidth corresponding to the broadband structure on the subband subset.

[0194] In an eighth aspect, alone or in combination with one or more of the first to seventh aspects, the CSI-RS is based on the same sequence for the widest bandwidth and for the subband subset.

[0195] In a ninth aspect, alone or in combination with one or more of the first to eighth aspects, the CSI-RS spans 48 resource blocks in a subband of the subband subset.

[0196] In a tenth aspect, alone or in combination with one or more of the first to ninth aspects, the resource elements intersect with resource elements of the broadband structure.

[0197] In an eleventh aspect, alone or in combination with one or more of the first to tenth aspects, the CSI-RS is used for periodic or semi-persistent CSI feedback.

[0198] In a twelfth aspect, alone or in combination with one or more of the first to eleventh aspects, the CSI-RS is used for aperiodic CSI feedback.

[0199] In a thirteenth aspect, alone or in combination with one or more of the first to twelfth aspects, process 900 may include rate matching a shared channel around resources of the CSI-RS based on a number of subbands available for the CSI-RS.

[0200] In a fourteenth aspect, alone or in combination with one or more of the first to thirteenth aspects, process 900 may include sending subband usage information identifying a subband subset, wherein the subband usage information identifying the subband subset is associated with at least one of: a COT-SI sent prior to a resource of a CSI-RS, a value associated with a grant for a shared channel, or downlink control information indicating a subband subset.

[0201] In a fifteenth aspect, alone or in combination with one or more of the first to fourteenth aspects, process 900 may include sending a grant for a subband subset; and rate matching a shared channel associated with the grant around resources associated with a CSI-RS on the subband subset.

[0202] In a sixteenth aspect, alone or in combination with one or more of the first to fifteenth aspects, process 900 may include sending a grant for a subband subset; sending a COT-SI before a CSI-RS; and rate matching a shared channel associated with the grant around resources associated with the CSI-RS on the subband subset based on sending the COT-SI before the CSI-RS.

[0203] In a seventeenth aspect, alone or in combination with one or more of the first to sixteenth aspects, process 900 may include sending a trigger for CSI feedback associated with the CSI-RS after indicating COT-SI for a subset of subbands in a plurality of subbands available for the CSI-RS.

[0204] In an eighteenth aspect, alone or in combination with one or more of the first to seventeenth aspects, the configuration information includes configurations for a plurality of different subband subsets among the plurality of subbands.

[0205] In a nineteenth aspect, alone or in combination with one or more of the first to eighteenth aspects, process 900 may include sending a trigger associated with a configuration for a particular subband subset among a plurality of different subband subsets based on the particular subband subset being available for CSI-RS.

[0206] In a twentieth aspect, alone or in combination with one or more of the first to nineteenth aspects, process 900 may include sending a trigger indicating a particular subband subset among a plurality of different subband subsets based on the particular subband subset being available for CSI-RS.

[0207] In a twenty-first aspect, alone or in combination with one or more of the first to twentieth aspects, the power level of the CSI-RS per resource element or per subband is independent of the number of subbands on which the CSI-RS is transmitted.

[0208] In a twenty-second aspect, alone or in combination with one or more of the first to twenty-first aspects, the power level of the CSI-RS per resource element or per subband is based on the number or configuration of subbands on which the CSI-RS is transmitted.

[0209] In a twenty-third aspect, alone or in combination with one or more of the first to twenty-second aspects, the power level of the CSI-RS per resource element or per subband is based on whether the CSI-RS is aperiodic, periodic, or semi-persistent.

[0210] In a twenty-fourth aspect, alone or in combination with one or more of the first to twenty-third aspects, process 900 may include determining a power level of the CSI-RS based on at least one of: a number or configuration of subbands on which the CSI-RS is transmitted, or information indicating a power level of the CSI-RS.

[0211] In an aspect 25, alone or in combination with one or more of aspects 1 to 24, when COT-SI associated with the CSI-RS can be transmitted before the CSI-RS, the CSI-RS is transmitted, and when COT-SI associated with the CSI-RS cannot be transmitted before the CSI-RS, the CSI-RS is not transmitted.

[0212] Although Fig. 9 Example blocks of process 900 are shown, but in some aspects, Fig. 9 Process 900 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in . Additionally or alternatively, two or more of the blocks of process 900 may be performed in parallel.

[0213] The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise forms disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired from practice of the aspects.

[0214] As used herein, the term "component" is intended to be broadly interpreted as hardware, firmware, or a combination of hardware and software. As used herein, a processor is implemented in hardware, firmware, or a combination of hardware and software. As used herein, the phrase "based on" is intended to be broadly interpreted to mean "based on."

[0215] As used herein, satisfying a threshold may refer to a value being greater than a threshold, greater than or equal to a threshold, less than a threshold, less than or equal to a threshold, equal to a threshold, not equal to a threshold, etc., depending on the context.

[0216] As used herein, a phrase referring to "at least one" of a list of items refers to any combination of those items, including single members. As an example, "at least one of a, b, or c" is intended to cover: a, b, c, ab, ac, bc, and abc.

[0217] The various illustrative logics, logical blocks, modules, circuits, and algorithmic processes described in conjunction with the aspects disclosed herein may be implemented as electronic hardware, computer software, or a combination of both. The interchangeability of hardware and software has been generally described in terms of functionality and is illustrated in the various illustrative components, blocks, modules, circuits, and processes described above. Whether such functionality is implemented in hardware or software depends on the specific application and the design constraints imposed on the overall system.

[0218] The hardware and data processing devices for implementing the various illustrative logics, logic blocks, modules, and circuits described in conjunction with the aspects disclosed herein can be implemented or executed using a general-purpose single-chip or multi-chip processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, or any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a group of microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration. In some aspects, specific processes and methods may be performed by circuits specific to a given function.

[0219] In one or more aspects, the functions described may be implemented in hardware, digital electronic circuitry, computer software, firmware (including the structures disclosed in this specification and their structural equivalents), or any combination thereof. Aspects of the subject matter described in this specification may also be implemented as one or more computer programs, i.e., one or more modules of computer program instructions, which are encoded on computer storage media for execution by data processing apparatus or to control the operation of data processing apparatus.

[0220] If implemented in software, the function can be stored or sent as one or more instructions or codes on a computer-readable medium. The process of the method or algorithm disclosed herein can be implemented in a processor executable software module that can reside on a computer-readable medium. Computer-readable media include both computer storage media and communication media, and communication media include any medium that can be enabled to transfer a computer program from one place to another. The storage medium can be any available medium that can be accessed by a computer. As an example and not a limitation, such computer-readable media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, disk storage or other magnetic storage devices, or any other medium that can be used to store the required program code in the form of an instruction or data structure and can be accessed by a computer. Similarly, any connection can be appropriately referred to as a computer-readable medium. The disk and optical disk used herein include compact disk (CD), laser disk, optical disk, digital versatile disk (DVD), floppy disk and blue optical disk, wherein the disk usually reproduces data magnetically, and the optical disk reproduces data optically with a laser. The combination of the above items should also be included in the scope of computer-readable media. Additionally, the operations of a method or algorithm may reside on a machine-readable medium and a computer-readable medium as one or any combination or set of codes and instructions, which may be incorporated into a computer program product.

[0221] Various modifications to the aspects described in the present disclosure may be apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the spirit or scope of the present disclosure. Therefore, the claims are not intended to be limited to the aspects shown herein, but will be consistent with the broadest scope consistent with the present disclosure, the principles disclosed herein, and the novel features.

[0222] In addition, those skilled in the art will readily appreciate that the terms "upper" and "lower" are sometimes used for ease of describing the drawings and indicate relative positioning corresponding to the orientation of the drawings on appropriately oriented pages and may not reflect the proper orientation of any device implemented.

[0223] Certain features described in this specification in the context of separate aspects may also be implemented in combination in a single aspect. Conversely, various features described in the context of a single aspect may also be implemented individually in multiple aspects or in any suitable sub-combination. Furthermore, while multiple features may be described above as acting in certain combinations and even initially claimed as such, in some cases one or more features from a claimed combination may be deleted from the combination, and a claimed combination may refer to a sub-combination or a variation of a sub-combination.

[0224] Similarly, although the operations are depicted in a specific order in the accompanying drawings, this should not be understood as requiring such operations to be performed in the specific order or sequential order shown, or requiring that all the operations shown be performed to achieve the desired result. In addition, the accompanying drawings may schematically depict one or more example processes in the form of a flow chart. However, other operations that are not depicted may be incorporated into the schematically illustrated example process. For example, one or more additional operations may be performed before, after, at the same time, or between any of the operations shown. In some cases, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the aspects described above should not be understood as requiring such separation in all aspects, and it should be understood that the described program components and systems can generally be integrated together in a single software product, or encapsulated in multiple software products. In addition, other aspects are within the scope of the appended claims. In some cases, the actions described in the claims may be performed in different orders, and still achieve the desired result.

Claims

1. A method of wireless communication performed by a device of a user equipment UE, comprising: receiving configuration information for a channel state information reference signal CSI-RS, The configuration information indicates that the CSI-RS is configured on multiple subbands; receiving information indicating availability of the plurality of subbands for the CSI-RS; selectively receiving the CSI-RS based on the configuration information and based on availability of the plurality of subbands for the CSI-RS, wherein when all subbands of the plurality of subbands are available for the CSI-RS, the CSI-RS is received, and when at least one subband of the plurality of subbands is not available for the CSI-RS, the CSI-RS is not received; and If the CSI-RS is received, channel state information CSI feedback is sent based on the configuration information.

2. The method of claim 1, wherein: The information indicates availability of the plurality of subbands for the CSI-RS when the CSI-RS is to be received.

3. The method of claim 1, wherein: Receiving the information indicating availability of the plurality of subbands for the CSI-RS comprises: A channel occupancy time (COT) structure indicator (SI) indicating availability of the plurality of subbands for the CSI-RS is received.

4. The method of claim 1, wherein: Receiving the information indicating availability of the plurality of subbands for the CSI-RS comprises: Downlink control information (DCI) indicating availability of the plurality of subbands for the CSI-RS is received.

5. The method of claim 1, receiving the information indicating availability of the plurality of subbands for the CSI-RS comprises: Before a transmission time of the CSI-RS, a channel occupancy time (COT) structure indicator (SI) indicating availability of the plurality of subbands for the CSI-RS is received.

6. The method of claim 1, wherein: The plurality of sub-bands are associated with a wideband structure.

7. The method of claim 1, wherein: The CSI-RS is received on resource elements associated with the plurality of subbands.

8. The method of claim 1, wherein: The information indicating availability of the plurality of subbands for the CSI-RS comprises a bitmap indicating one or more resource block (RB) sets.

9. A device for a user equipment UE for wireless communication, comprising: A first interface, wherein the first interface is configured as: Obtaining configuration information for a channel state information reference signal CSI-RS, in, The configuration information indicates that the CSI-RS is configured on a plurality of subbands; obtaining information indicating availability of the plurality of subbands for the CSI-RS; as well as selectively obtaining the CSI-RS based on the configuration information and based on availability of the plurality of subbands for the CSI-RS, wherein when all subbands of the plurality of subbands are available for the CSI-RS, the CSI-RS is received, and when at least one subband of the plurality of subbands is not available for the CSI-RS, the CSI-RS is not received; and The first interface or the second interface is configured as: If the CSI-RS is obtained, channel state information CSI feedback is output based on the configuration information.

10. The device of claim 9, wherein: The information indicates availability of the plurality of subbands for the CSI-RS when the CSI-RS is to be received.

11. The device of claim 9, wherein: In order to obtain the information indicating availability of the plurality of subbands for the CSI-RS, the first interface is configured to: A channel occupancy time (COT) structure indicator (SI) indicating availability of the plurality of subbands for the CSI-RS is obtained.

12. The device of claim 9, wherein: In order to obtain the information indicating availability of the plurality of subbands for the CSI-RS, the first interface is configured to: Downlink control information (DCI) indicating availability of the plurality of subbands for the CSI-RS is obtained.

13. The device of claim 9, wherein: In order to obtain the information indicating availability of the plurality of subbands for the CSI-RS, the first interface is configured to: Before the transmission time of the CSI-RS, a channel occupancy time COT structure indicator SI indicating availability of the plurality of subbands for the CSI-RS is obtained.

14. The device of claim 9, wherein: The plurality of sub-bands are associated with a wideband structure.

15. The device of claim 9, wherein: The CSI-RS is received on resource elements associated with the plurality of subbands.

16. The device of claim 9, wherein: The information indicating availability of the plurality of subbands for the CSI-RS comprises a bitmap indicating one or more resource block (RB) sets.

17. A wireless communication method performed by a device of a network entity, comprising: Send configuration information for a channel state information reference signal CSI-RS, The configuration information indicates that the CSI-RS is configured on multiple subbands; transmitting information indicating availability of the plurality of subbands for the CSI-RS; selectively transmitting the CSI-RS based on the configuration information and based on availability of the plurality of subbands for the CSI-RS, wherein when all subbands among the multiple subbands are available for the CSI-RS, the CSI-RS is transmitted, and when at least one subband among the multiple subbands is not available for the CSI-RS, the CSI-RS is not transmitted; and If the CSI-RS is transmitted, channel state information (CSI) feedback is received based on the configuration information.

18. The method of claim 17, wherein: The information indicates availability of the plurality of subbands for the CSI-RS when the CSI-RS is to be transmitted.

19. The method of claim 17, wherein: The transmitting the information indicating the availability of the plurality of subbands for the CSI-RS comprises: The channel occupancy time (COT) structure indicator (SI) indicating availability of the plurality of subbands for the CSI-RS is transmitted.

20. The method of claim 17, wherein: The transmitting the information indicating the availability of the plurality of subbands for the CSI-RS comprises: Before the transmission time of the CSI-RS, a channel occupancy time COT structure indicator SI indicating availability of the plurality of subbands for the CSI-RS is transmitted.

21. The method of claim 17, wherein: The plurality of sub-bands are associated with a wideband structure.

22. The method of claim 17, wherein: The information indicating availability of the plurality of subbands for the CSI-RS comprises a bitmap indicating one or more resource block (RB) sets.

23. An apparatus of a network entity for wireless communication, comprising: A first interface, wherein the first interface is configured as: Output configuration information for a channel state information reference signal CSI-RS, The configuration information indicates that the CSI-RS is configured on multiple subbands; outputting information indicating availability of the plurality of subbands for the CSI-RS; and selectively outputting the CSI-RS based on the configuration information and based on availability of the plurality of subbands for the CSI-RS, wherein when all subbands among the multiple subbands are available for the CSI-RS, the CSI-RS is output, and when at least one subband among the multiple subbands is not available for the CSI-RS, the CSI-RS is not output; and The first interface or the second interface is configured as: If the CSI-RS is output, channel state information CSI feedback is obtained based on the configuration information.

24. The device of claim 23, wherein: The information indicates availability of the plurality of subbands for the CSI-RS when the CSI-RS is to be output.

25. The apparatus of claim 23, wherein: To output the information indicating availability of the plurality of subbands for the CSI-RS, the first interface is configured to: A channel occupancy time (COT) structure indicator (SI) indicating availability of the plurality of subbands for the CSI-RS is output.

26. The apparatus of claim 23, wherein: To output the information indicating availability of the plurality of subbands for the CSI-RS, the first interface is configured to: Downlink control information (DCI) indicating availability of the plurality of subbands for the CSI-RS is output.

27. The apparatus of claim 23, wherein: To output the information indicating availability of the plurality of subbands for the CSI-RS, the first interface is configured to: Before the transmission time of the CSI-RS, a channel occupancy time COT structure indicator SI indicating availability of the plurality of subbands for the CSI-RS is output.

28. The apparatus of claim 23, wherein: The plurality of sub-bands are associated with a wideband structure.

29. The apparatus of claim 23, wherein: The CSI-RS is output on resource elements associated with the plurality of subbands.

30. The apparatus of claim 23, wherein: The information indicating availability of the plurality of subbands for the CSI-RS comprises a bitmap indicating one or more resource block (RB) sets.

Images