Multicast sidelink CSI-RS with selective CSI reporting

Abstract

Some aspects provide a method for wireless communication by a first wireless device. The method generally includes transmitting one or more sidelink channel state information (CSI) reference signals (CSI-RS) targeted to a group of user equipment (UEs). The method generally includes requesting one or more CSI reports from one or more UEs selected from the group of UEs. The method generally includes receiving one or more CSI reports from the selected one or more UEs.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Application No. 17 / 007,349, filed on August 31, 2020, which claims the benefit of and priority to U.S. Provisional Application No. 62 / 899,694, filed on September 12, 2019, both of which are assigned to the assignee of this application and are hereby expressly incorporated herein by reference in their entirety as if fully set forth below and for all applicable purposes. Technical Field

[0003] Aspects of the present disclosure relate to wireless communications and, more particularly, to techniques for managing channel state information (CSI) reporting between user equipment (UEs) via a sidelink channel. Background Art

[0004] Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, broadcast, etc. These 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 Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, 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, to name just a few.

[0005] These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate at a city, country, region, and even global level. New radio (e.g., 5G NR) is an example of an emerging telecommunication standard. NR is an enhancement set of the LTE mobile standard promulgated by 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 using OFDMA with cyclic prefix (CP) on downlink (DL) and uplink (UL). To this end, NR supports beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation.

[0006] However, as the demand for mobile broadband access continues to grow, there is a need for further improvements to NR and LTE technologies. Preferably, these improvements should be applicable to other multiple access technologies and the telecommunication standards that employ these technologies. Summary of the invention

[0007] The systems, methods, and devices of the present disclosure each have several innovative aspects, no single aspect of which is solely responsible for its desirable attributes. Without limiting the scope of the present disclosure as expressed in the appended claims, some features will now be briefly discussed. After considering this discussion, and especially after reading the section entitled "Detailed Description," it will be understood how the features of the present disclosure provide advantages including improved sidelink channel state information (CSI) reporting.

[0008] Aspects of the present disclosure may be implemented in a method for wireless communication by a first wireless device. The method generally includes transmitting one or more sidelink CSI reference signals (CSI-RS) targeted to a group of user equipment (UE). The method generally includes requesting one or more CSI reports from one or more UEs selected from the group of UEs. The method generally includes receiving one or more CSI reports from the selected one or more UEs.

[0009] Various aspects of the present disclosure may be implemented in a method for wireless communication by a UE. The method generally includes receiving one or more sidelink CSI-RSs targeted at a UE group including the UE from a first wireless device. The method generally includes receiving signaling indicating that the UE is selected to transmit a CSI report generated based on the one or more sidelink CSI-RSs. The method generally includes generating a CSI report based on the one or more sidelink CSI-RSs. The method generally includes transmitting the CSI report to the first wireless device.

[0010] Aspects of the present disclosure may be implemented in an apparatus for wireless communication by a first wireless device. The apparatus generally includes at least one processor configured to transmit one or more sidelink CSI-RSs targeted to a UE group. The at least one processor is configured to request one or more CSI reports from one or more UEs selected in the UE group. The at least one processor is configured to receive one or more CSI reports from the selected one or more UEs. The apparatus generally includes a memory coupled to the at least one processor.

[0011] Aspects of the present disclosure may be implemented in an apparatus for wireless communication by a UE. The apparatus generally includes at least one processor configured to receive one or more sidelink CSI-RSs targeted at a UE group including the UE from a first wireless device. The at least one processor is configured to receive signaling indicating that the UE is selected to transmit a CSI report generated based on the one or more sidelink CSI-RSs. The at least one processor is configured to generate a CSI report based on the one or more sidelink CSI-RSs. The at least one processor is configured to transmit the CSI report to the first wireless device. The apparatus generally includes a memory coupled to the at least one processor.

[0012] Aspects of the present disclosure may be implemented in an apparatus for wireless communication by a first wireless device. The apparatus generally includes means for transmitting one or more sidelink CSI-RSs targeted to a group of UEs. The apparatus generally includes means for requesting one or more CSI reports from one or more UEs selected from the group of UEs. The apparatus generally includes means for receiving one or more CSI reports from the selected one or more UEs.

[0013] Various aspects of the present disclosure may be implemented in an apparatus for wireless communication by a UE. The apparatus generally includes a device for receiving one or more sidelink CSI-RSs targeted at a UE group including the UE from a first wireless device. The apparatus generally includes a device for receiving signaling indicating that the UE is selected to transmit a CSI report generated based on the one or more sidelink CSI-RSs. The apparatus generally includes a device for generating a CSI report based on the one or more sidelink CSI-RSs. The apparatus generally includes a device for transmitting the CSI report to the first wireless device.

[0014] Various aspects of the present disclosure may be implemented in a computer-readable medium having computer-executable code stored thereon for wireless communication. The computer-readable medium generally includes code for transmitting one or more sidelink CSI-RSs targeted to a group of UEs. The computer-readable medium generally includes code for requesting one or more CSI reports from one or more UEs selected from the group of UEs. The computer-readable medium generally includes code for receiving one or more CSI reports from the selected one or more UEs.

[0015] Various aspects of the present disclosure may be implemented in a computer-readable medium on which computer-executable code for wireless communication is stored. The computer-readable medium generally includes code for receiving one or more sidelink CSI-RSs targeted at a UE group including the UE from a first wireless device. The computer-readable medium generally includes code for receiving signaling indicating that the UE is selected to transmit a CSI report generated based on the one or more sidelink CSI-RSs. The computer-readable medium generally includes code for generating a CSI report based on the one or more sidelink CSI-RSs. The computer-readable medium generally includes code for transmitting the CSI report to the first wireless device.

[0016] To achieve the foregoing and related ends, one or more aspects include the features fully described below and particularly pointed out in the claims. The following description and the accompanying drawings set forth in detail some illustrative features of one or more aspects. However, these features are only indicative of several of the various ways in which the principles of the various aspects can be employed. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The 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. However, the accompanying drawings illustrate only some typical aspects of the present disclosure and are therefore not to be considered as limiting its scope. Other features, aspects and advantages will become apparent from the description, drawings and claims.

[0018] Figure 1 An example wireless communication network is shown in which aspects of the present disclosure may be performed.

[0019] Figure 2 Shown is a block diagram illustrating an example base station (BS) and an example user equipment (UE) according to some aspects of the present disclosure.

[0020] Figure 3 is an example frame format for certain wireless communication systems (e.g., New Radio (NR)) in accordance with certain aspects of the present disclosure.

[0021] Figure 4 An example vehicle-to-everything (V2X) communication system is illustrated in accordance with certain aspects of the present disclosure.

[0022] Figure 5 Another example V2X communication system in accordance with certain aspects of the present disclosure is illustrated.

[0023] Figure 6 is a flow diagram illustrating example operations for wireless communications by a first wireless device in accordance with some aspects of the present disclosure.

[0024] Figure 7 is a flow diagram illustrating example operations for wireless communications by an apparatus in accordance with some aspects of the present disclosure.

[0025] Figure 8 is a diagram illustrating example CSI reporting configurations and reporting for wireless communications in accordance with some aspects of the present disclosure.

[0026] Fig. 9 is a block diagram illustrating an example communication device that may include various components configured to perform operations of the techniques disclosed herein in accordance with aspects of the present disclosure.

[0027] Fig.10 is a block diagram illustrating an example communication device that may include various components configured to perform operations of the techniques disclosed herein in accordance with aspects of the present disclosure.

[0028] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one aspect may be beneficially utilized in other aspects without specific recitation. DETAILED DESCRIPTION

[0029] Various aspects of the present disclosure provide apparatus, methods, processing systems, and computer-readable media for managing channel state information (CSI) reporting via a sidelink channel between sidelink devices, such as between user equipment (UEs). As will be described, the techniques presented herein allow UEs transmitting a CSI reference signal (CSI-RS) to select which UEs to send CSI reports based on the CSI-RS.

[0030] Allowing a UE to transmit a sidelink CSI-RS (such as a multicast CSI-RS) to a set of other UEs to select which UEs in the set report CSI can help better utilize system resources, adapt sidelink CSI reports to certain UEs of interest, and / or help interleave CSI reports from multiple UEs.

[0031] The following description provides an example of a multicast sidelink CSI-RS with a selected CSI report, without limiting the scope, applicability, or examples set forth in the claims. Changes may be made to the functions and arrangements of the elements discussed without departing from the scope of the present disclosure. Various examples may appropriately omit, replace, or add various procedures or components. For example, the described method may be performed in an order different from the order described, and various steps may be added, omitted, or combined. Moreover, the features described with reference to some examples may be combined in some other examples. For example, any number of aspects set forth herein may be used to implement a device or practice method. In addition, the scope of the present disclosure is intended to cover such devices or methods practiced using other structures, functionality, or structures and functionality as a supplement to the various aspects of the present disclosure set forth herein or in addition. It should be understood that any aspect of the present disclosure disclosed herein may be implemented by one or more elements of the claims.

[0032] In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a specific radio access technology (RAT) and may operate on one or more frequencies. RAT may also be referred to as radio technology, air interface, etc. Frequency may also be referred to as carrier, subcarrier, frequency channel, frequency modulation, subband, etc. Each frequency may support a single RAT in a given geographic area to avoid interference between wireless networks of different RATs. In some cases, a 5G NR RAT network may be deployed.

[0033] The techniques described herein can be used for various wireless networks and radio technologies. Although various aspects may be described herein using terms typically associated with 3G, 4G, and / or new radio (e.g., 5G NR) wireless technologies, various aspects of the present disclosure may be applied in communication systems based on other generations.

[0034] NR access (e.g., 5G NR) can support various wireless communication services, such as enhanced mobile broadband (eMBB) targeting wide bandwidth, millimeter wave (mmWave) targeting high carrier frequency, massive machine type communication MTC (mMTC) targeting non-backward compatible MTC technology, or mission-critical services targeting ultra-reliable low latency communication (URLLC). These services may include latency and reliability requirements. These services may also have different transmission time intervals (TTIs) to meet corresponding quality of service (QoS) requirements. In addition, these services can coexist in the same time domain resources (e.g., time slots or subframes) or frequency domain resources (e.g., component carriers).

[0035] Figure 1 An example wireless communication network 100 is illustrated in which aspects of the present disclosure may be performed. Figure 1 As shown, UE 120a and / or UE 120b may include a sidelink CSI reporting module (122a, 122b) that may be configured to perform operations as described herein to manage sidelink CSI reporting.

[0036] like Figure 1 As shown in , the wireless communication network 100 may be in communication with a core network 132. The core network 132 may be in communication with one or more base stations (BSs) 110 110a-z (also each individually referred to herein as BS 110 or collectively referred to herein as BS 110) and / or user equipments (UEs) 120a-y (also each individually referred to herein as UE 120 or collectively referred to herein as UE 120) in the wireless communication network 100 via one or more interfaces.

[0037] BS 110 may provide communication coverage for a particular geographic area (sometimes referred to as a "cell"), which may be stationary or mobile depending on the location of mobile BS 110. In some examples, BS 110 may be interconnected to each other or to one or more other BSs or network nodes (not shown) in wireless communication network 100 via various types of backhaul interfaces (e.g., direct physical connections, wireless connections, virtual networks, etc.) using any suitable transport network. Figure 1 In the example shown in FIG. 1 , BSs 110a, 110b, and 110c may be macro BSs for macro cells 102a, 102b, and 102c, respectively. BS 110x may be a pico BS for pico cell 102x. BSs 110y and 110z may be femto BSs for femto cells 102y and 102z, respectively. A BS may support one or more cells.

[0038] The BS 110 communicates with the UE 120 in the wireless communication network 100. The UE 120 may be dispersed throughout the wireless communication network 100, and each UE 120 may be stationary or mobile.

[0039] The wireless communication network 100 may also include a relay station (e.g., relay station 110r) (also referred to as a relay, etc.), which receives transmissions of data or other information from an upstream station (e.g., BS110a or UE 120r) and sends transmissions of data or other information to a downstream station (e.g., UE 120 or BS110), or which relays transmissions between UEs 120 to facilitate communication between the devices.

[0040] The network controller 130 may be coupled to a set of BSs 110 and provide coordination and control of the BSs 110. The network controller 130 may communicate with the BSs 110 via a backhaul. In various aspects, the network controller 130 may be in communication with a core network 132 (e.g., a 5G core network (5GC)), which provides various network functions such as access and mobility management, session management, user plane functions, policy control functions, authentication server functions, unified data management, application functions, network open functions, network repository functions, network slice selection functions, etc.

[0041] Figure 2 1 and 120a (eg, in a BS 110a and a UE 120a) that can be used to implement various aspects of the present disclosure are illustrated. Figure 1 Example components of the wireless communication network 100).

[0042] At BS 110a, a transmit processor 220 may receive data from a data source 212 and control information from a controller / processor 240. The control information may be for a physical broadcast channel (PBCH), a physical control format indicator channel (PCFICH), a physical hybrid ARQ indicator channel (PHICH), a physical downlink control channel (PDCCH), a group common PDCCH (GC PDCCH), etc. The data may be for a physical downlink shared channel (PDSCH), etc. The processor 220 may process (e.g., encode and symbol map) the data and the control information to obtain data symbols and control symbols, respectively. The transmit processor 220 may also generate reference symbols (such as for a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a channel state information reference signal (CSI-RS)). The transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on ​​data symbols, control symbols, or reference symbols, where applicable, and may provide an output symbol stream to a modulator (MOD) in a transceiver 232a-232t. Each modulator may process a respective output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator may further process (e.g., convert to analog, amplify, filter, and up-convert) the output sample stream to obtain a downlink signal. The downlink signals from the modulators in the transceivers 232a-232t may be transmitted via antennas 234a-234t, respectively.

[0043] At UE 120a, antennas 252a-252r may receive downlink signals from BS 110a (or sidelink signals from sidelink devices such as UE 120b) and may provide received signals to demodulators (DEMODs) 254a-254r in the transceiver, respectively. Each demodulator may condition (e.g., filter, amplify, downconvert, and digitize) a respective received signal to obtain input samples. Each demodulator 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 demodulators in transceivers 254a-254r, perform MIMO detection on the received symbols where applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for UE 120a to a data sink 260, and provide decoded control information to a controller / processor 280.

[0044] On the uplink or sidelink, at the UE 120a, a transmit processor 264 may receive and process data from a data source 262 (e.g., for a physical uplink shared channel (PUSCH) or a physical sidelink shared channel (PSSCH)) and control information from a controller / processor 280 (e.g., for a physical uplink control channel (PUCCH) or a physical sidelink control channel (PSCCH)). The transmit processor 264 may also generate reference symbols for reference signals (e.g., a sounding reference signal (SRS) or a CSI-RS). The symbols from the transmit processor 264 may be precoded by the TX MIMO processor 266, if applicable, further processed by a modulator in the transceiver 254a-254r (e.g., for SC-FDM, etc.), and transmitted to the BS 110a or the sidelink UE 120b. At BS 110a (or at a receiving side link UE), the uplink signal from UE 120a may be received by antenna 234, processed by demodulator 232, detected by MIMO detector 236 if applicable, and further processed by receive processor 238 to obtain decoded data and control information sent by UE 120a. Receive processor 238 may provide decoded data to data sink 239 and decoded control information to controller / processor 240.

[0045] Memories 242 and 282 may store data and program codes, respectively, for BS 110 and UE 120. Scheduler 244 may schedule UEs for data transmission on the downlink or uplink.

[0046] The antennas 252, processors 266, 258, 264 and / or controller / processor 280 of the UE 120a, and / or the antennas 234, processors 220, 230, 238 and / or controller / processor 240 of the BS 110a may be used to perform the various techniques and methods described herein. Figure 2 As shown, the controller / processor 280 of UE 120a has a sidelink CSI reporting module 122 that can be configured to configure / schedule UE 120's own CSI reporting and / or process sidelink CSI reports from another UE. Although shown at the controller / processor, other components of the UE may also be used to perform the operations described herein.

[0047] NR can utilize orthogonal frequency division multiplexing (OFDM) with cyclic prefix (CP) on uplink and downlink. NR can support half-duplex operation using time division duplex (TDD). OFDM and single carrier frequency division multiplexing (SC-FDM) divide the system bandwidth into multiple orthogonal subcarriers, which are also often called frequency modulation, frequency slot, etc. Each subcarrier can be modulated with data. Modulation code elements can be sent in the frequency domain under OFDM and in the time domain under SC-FDM. The spacing between adjacent subcarriers can be fixed, and the total number of subcarriers can depend on the system bandwidth. The minimum resource allocation (so-called resource block (RB)) can be 12 consecutive subcarriers. The system bandwidth can also be divided into subbands. For example, one subband can cover multiple RBs. NR can support a base subcarrier spacing (SCS) of 15KHz, and other SCSs (e.g., 30kHz, 60kHz, 120kHz, 240kHz, etc.) can be defined relative to the base SCS.

[0048] Figure 3 300 is a diagram showing an example of a frame format for NR. The transmission timeline of each of the downlink and uplink may be divided into units of radio frames. Each radio frame may have a predetermined duration (e.g., 10 ms) and may be divided into 10 subframes with indices 0 to 9, each subframe being 1 ms. Each subframe may include a variable number of slots (e.g., 1, 2, 4, 8, 16, ... slots), depending on the SCS. Each slot may include a variable number of symbol periods (e.g., 7, 12, or 14 symbols), depending on the SCS. An index may be assigned to the symbol period in each slot. The subslot structure refers to a transmission time interval having a duration less than a slot (e.g., 2, 3, or 4 symbols). Each symbol in a slot may indicate a link direction (e.g., DL, UL, or flexible) for data transmission, and the link direction for each subframe may be dynamically switched. The link direction may be based on the slot format. Each slot may include DL / UL data and DL / UL control information.

[0049] In some cases, two or more subordinate entities (e.g., UE) may use sidelink signals to communicate with each other. As described above, vehicle-to-vehicle (V2V) and vehicle-to-everything (V2X) communications are examples of communications that can be transmitted via sidelinks. Other applications of sidelink communications may include public safety or service announcement communications, proximity service communications, UE-to-network relay communications, device-to-device (D2D) communications, Internet of Everything (IoE) communications, Internet of Things (IoT) communications, mission-critical mesh communications, and other suitable applications. In general, a sidelink may refer to a direct link between a subordinate entity (e.g., UE1) and another subordinate entity (e.g., UE2). In this way, the sidelink may be used to transmit and receive communications (also referred to herein as "sidelink signals") without relaying communications through a scheduling entity (e.g., BS), even if the scheduling entity can be used for scheduling or control purposes. In some examples, sidelink signals may be communicated using licensed spectrum (unlike wireless local area networks, which typically use unlicensed spectrum).

[0050] Various sidelink channels may be used for sidelink communications, including a physical sidelink discovery channel (PSDCH), a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), and a physical sidelink feedback channel (PSFCH). The PSDCH may carry discovery expressions that enable neighboring devices to discover each other. The PSCCH may carry control signaling for data transmission (such as sidelink resource configuration or other parameters), while the PSSCH may carry data transmission. The PSFCH may carry feedback, such as channel state information (CSI) related to the sidelink channel quality.

[0051] Figure 4 and 5 A diagrammatic representation of an example vehicle-to-everything (V2X) system is shown according to some aspects of the present disclosure. For example, Figure 4 and Figure 5 The vehicles shown may communicate via a sidelink channel and may perform sidelink CSI reporting as described herein.

[0052] Figure 4 and Figure 5 The V2X system provided in provides two complementary transmission modes. Figure 4 The first transmission mode, shown by way of example in FIG. 1 , involves direct communication between parties that are adjacent to each other in a local area (e.g., also referred to as sidelink communication). Figure 5 The second transmission mode illustrated by way of example in FIG. 8 involves network communication through a network, which may be implemented through a Uu interface (eg, a wireless communication interface between a radio access network (RAN) and a UE).

[0053] Reference Figure 4 , a V2X system 400 (e.g., including vehicle-to-vehicle (V2V) communications) is illustrated with two vehicles 402, 404. A first transmission mode allows direct communication between different parties in a given geographic location. As illustrated, the vehicles may have a wireless communication link 406 (vehicle-to-pedestrian (V2P)) with an individual (e.g., via a UE) through a PC5 interface. Communications between vehicles 402 and 404 may also occur through a PC5 interface 408. Communications (V2I) from vehicle 402 to other highway components (e.g., highway components 410, such as traffic signals or signs) may occur in a similar manner through PC5 interface 312. For Figure 4 For each communication link illustrated in FIG. 4 , bidirectional communication can be performed between elements, so each element can be a transmitter and receiver of information. The V2X system 400 can be a self-managed system implemented without the assistance of a network entity. The self-managed system can achieve improved spectrum efficiency, reduced costs, and increased reliability because no network service interruption occurs during switching operations for moving vehicles. The V2X system can be configured to operate in a licensed or unlicensed spectrum, whereby any vehicle with an equipped system can access the common frequency and share information. Such coordinated / shared spectrum operations allow safe and reliable operations.

[0054] Figure 5 A V2X system 500 is shown for communicating between a vehicle 552 and a vehicle 554 through a network entity 556. These network communications may occur through discrete nodes (such as base stations, e.g., eNBs or gNBs) that send information to and receive information from (e.g., relay information between) the vehicles 552, 554. Network communications through vehicle-to-network (V2N) links 558 and 510 may be used, for example, for long-range communications between vehicles, such as for communicating that there is a traffic accident at a distance ahead along a road or highway. Other types of communications may be sent by nodes to vehicles, such as traffic flow conditions, road hazard warnings, environmental / weather reports, service station availability, and other similar examples. Such data may be obtained from a cloud-based sharing service.

[0055] As mentioned above, aspects of the present disclosure relate to managing sidelink CSI reporting. CSI in new radio (NR) includes multiple channel quality metrics. For example, channel quality metrics may include channel quality indicator (CQI); precoding matrix indicator (PMI), CSI-RS resource indicator (CRI), strongest layer indication (SLI), rank indication (RI), and L1 reference signal received power (L1-RSRP) (for beam management).

[0056] For vehicle-to-everything (V2X) deployments (such as Figure 4 and 5 As described above, CSI reporting can be enabled and disabled by configuration. For flexibility, a device can be configured to report a subset of metrics for CSI reporting.

[0057] The CSI reporting configuration and scheduling in NR may depend on the type of CSI report. The type of channel carrying the CSI report may depend on the type of CSI report. For example, periodic CSI reports may be carried on the short physical uplink control channel (PUCCH) or the long PUCCH, while semi-persistent (SP) CSI reports may be carried on the long PUCCH or the physical uplink shared channel (PUSCH). Resources and transmission parameters (such as modulation and coding scheme (MCS)) for SP-CSI on PUSCH may be semi-persistently allocated using the downlink control channel (DCI). SP-CSI may support Type II CSI reports with a minimum periodicity of 5 milliseconds. In some cases, SP CSI reports may not be supported for non-periodic CSI-RS (although lack of support does not preclude one CSI report carried by multiple uplink (UL) reporting instances). In NR, non-periodic CSI reports may be carried on PUSCH multiplexed with uplink data or not. Periodic and semi-persistent (P / SP) reporting in NR can support the following periodicities {5, 10, 20, 40, 80, 160, 320 slots}.

[0058] The sidelink CSI-RS may support CQI and / or RI measurements for no more than two ports. The sidelink CSI-RS may be confined to the physical sidelink shared channel (PSSCH) transmission. However, for beam management and / or multiple-input multiple-output (MIMO), more detailed CSI reporting may be required. These various sidelink use cases may involve different CSI reporting procedures (e.g., depending on the feedback and the amount of available resources). There are differences between sidelink and regular (Uu / access link) CSI reporting. For example, on the Uu interface, CSI reporting is asymmetric, where the gNB (in NR) schedules all CSI-RS and CSI reports. However, in sidelink CSI reporting, the relationship between the transmitter and the receiver can be more symmetric (e.g., from one UE to another UE).

[0059] Therefore, techniques for sidelink CSI reporting are desirable.

[0060] Example Multicast Sidelink CSI-RS with Selective CSI Reporting

[0061] Various aspects of the present disclosure provide for multicast sidelink channel state information reference signals (CSI-RS) with selective CSI reporting. According to certain aspects, a sidelink user equipment (UE) may multicast a CSI-RS to multiple UEs. The UEs may be selectively configured to report CSI. For example, a UE and / or a base station (BS) transmitting the CSI-RS may select (e.g., and configure / instruct / request) UEs (e.g., a subset of UEs) to provide CSI reports for the multicast CSI-RS.

[0062] Figure 6 600 for wireless communication in accordance with certain aspects of the present disclosure. For example, operations 600 may be performed, for example, by a first sidelink device such as a UE (e.g., by Figure 1 UE 120a transmits a sidelink CSI-RS to a group of UEs and receives one or more CSI reports. Operation 600 may be implemented as a process on one or more processors (e.g., Figure 2 In addition, signal transmission and reception by the UE in operation 600 may be performed by one or more antennas (e.g., Figure 2 In some aspects, the transmission and / or reception of signals by the UE may be achieved by obtaining and / or outputting signals via a bus interface of one or more processors (eg, controller / processor 280).

[0063] Operation 600 begins at 602, where one or more sidelink CSI-RS targeted to a group of UEs are transmitted. As used herein, the term "targeted to" generally means that these UEs are the intended recipients of the CSI-RS. In general, resources and parameters for groupcast CSI-RS may be configured by a base station (e.g., a 5G New Radio (NR) g Node B (gNB)), configured by a sidelink radio resource control (RRC), scheduled by sidelink control information (SCI) from a UE transmitting the CSI, or scheduled by downlink control information (DCI) from a BS. At 604, the UE requests one or more CSI reports from one or more UEs selected from the group of UEs. At 606, the UE receives one or more CSI reports from the selected one or more UEs.

[0064] Figure 7 700 is a flow diagram illustrating example operations 700 for wireless communication in accordance with certain aspects of the present disclosure. For example, operations 700 may be performed by a UE (e.g., by Figure 1 UE 120b processes the sidelink CSI report configured / scheduled by UE 120a). Operation 700 may be implemented as a processor (e.g., Figure 2In addition, signal transmission and reception by the UE in operation 700 may be performed by one or more antennas (e.g., Figure 2 In some aspects, the transmission and / or reception of signals by the UE may be achieved by obtaining and / or outputting signals via a bus interface of one or more processors (eg, controller / processor 280).

[0065] Operations 700 begin at 702, where one or more sidelink CSI-RSs targeting a group of UEs including the UE are received from a first wireless device. At 704, the UE receives signaling indicating that the UE is selected to transmit a CSI report generated based on the one or more sidelink CSI-RSs. At 706, the UE generates a CSI report based on the one or more sidelink CSI-RSs. At 708, the UE transmits the CSI report to the first wireless device.

[0066] You can refer to Figure 8 To understand the diagram Figure 6 and 7 Operations 600 and 700. Figure 8 As shown, UE A multicasts the sidelink CSI-RS to a group of other UEs (UE B1, UE B2, UE B3, and UE B4). As illustrated, only UE B2 transmits a CSI report based on the multicast sidelink CSI-RS (while UE B1, UE B2, and UE B3 do not). The selection of UE B2 may be based on a CSI report setting. For example, the CSI report setting may be sent via SCI (e.g., from UE A), a configuration of the gNB (not shown), or via dynamic signaling (e.g., DCI) of the gNB. Although in Figure 8 In the example shown, only one UE (UE B2) is selected, but in some aspects, multiple UEs may be selected (eg, instructed, configured, and / or requested) to report CSI.

[0067] In some examples, the UE transmitting the CSI-RS may control how the selected UE transmits its CSI report. For example, the UE transmitting the CSI-RS may request time-staggered CSI reports or simultaneous CSI reports in order to receive all CSI reports. Simultaneous CSI reports may be requested to be multiplexed. These simultaneous CSI reports may be multiplexed via frequency division multiplexing (FDM), space division multiplexing (SDM), or both FDM and SDM.

[0068] In some examples, the UE may poll for CSI reports. For example, if CSI reports may be received from a subset of a group of UEs receiving CSI-RS using the same receive (Rx) beam, these UEs receiving CSI-RS may be polled (e.g., via SCI from the UE transmitting the CSI-RS) or may be configured (e.g., via sidelink RRC from the UE transmitting the CSI-RS) to transmit simultaneous reports (e.g., using FDM, SDM, or both FDM and SDM).

[0069] In some examples, the UE transmitting the CSI-RS may only transmit the CSI to one UE in the UE group (e.g. Figure 8 ) or request CSI reports only from a subset of the group. In some examples, the selection (which UEs) may be made by the CSI reporting settings via the SCI.

[0070] In some examples, the selection (of which UEs to report CSI) may be based on the configuration of the gNB or dynamic signaling by the gNB (e.g., via DCI). The DCI triggering the CSI report may also be sent to the UE transmitting the CSI-RS to receive the CSI report (as a group DCI or an individual UE-specific DCI).

[0071] In some examples, a group DCI transmitted to the UE transmitting the CSI-RS and a group of all UEs receiving the CSI-RS may trigger a CSI report. The group DCI may also indicate the UE and / or a subset of UEs transmitting the CSI.

[0072] The content of the CSI report may also be configured. For example, a first subset of CSI parameters may be reported by all UEs through time-staggered CSI reporting, while a second subset of CSI parameters may be reported by only one UE or a subset of UEs in a group. The distinction between the two subsets of CSI parameters may be based on whether they correspond to coherent CSI information (e.g., beam, precoding matrix indicator (PMI)) or incoherent CSI information (e.g., channel quality indicator (CQI)).

[0073] Aspects of the present disclosure provide mechanisms that allow a UE transmitting a sidelink CSI-RS to select which UEs (in a group of UEs) to report CSI based on the transmitted CSI-RS.

[0074] Fig. 9 The description may include a method configured to perform operations for the techniques disclosed herein (such as Figure 6900 includes various components (e.g., corresponding to means-plus-function components) of the communication device 900 and the operations explained in the foregoing. The communication device 900 includes a processing system 902 coupled to a transceiver 908 (e.g., a transmitter and / or a receiver). The transceiver 908 is configured to transmit and receive signals for the communication device 900 (such as various signals as described herein) via an antenna 910. The processing system 902 may be configured to perform processing functions for the communication device 900, including processing signals received and / or to be transmitted by the communication device 900.

[0075] The processing system 902 includes a processor 904 coupled to a computer readable medium / memory 912 via a bus 906. In some aspects, the computer readable medium / memory 912 is configured to store a program that, when executed by the processor 904, causes the processor 904 to execute Figure 6 , or instructions (e.g., computer executable code) for performing the operations illustrated in or other operations discussed herein for managing various techniques for CSI reporting between UEs via a sidelink channel. In certain aspects, the computer-readable medium / memory 912 stores code 914 for transmitting one or more sidelink CSI-RSs targeted to a UE group; code 916 for requesting one or more CSI reports from one or more UEs selected in the UE group; and code 918 for receiving one or more CSI reports from the selected one or more UEs. In certain aspects, the processor 904 has a circuit system configured to implement the code stored in the computer-readable medium / memory 912. The processor 904 includes a circuit system 924 for transmitting one or more sidelink CSI-RSs targeted to a UE group; a circuit system 926 for requesting one or more CSI reports from one or more UEs selected in the UE group; and a circuit system 928 for receiving one or more CSI reports from the selected one or more UEs.

[0076] Fig.10 The description may include a method configured to perform operations for the techniques disclosed herein (such as Figure 7 1000 includes a communication device 1000 including various components (e.g., corresponding to means-plus-function components) of the operations illustrated in . The communication device 1000 includes a processing system 1002 coupled to a transceiver 1008 (e.g., a transmitter and / or a receiver). The transceiver 1008 is configured to transmit and receive signals (such as various signals as described herein) for the communication device 1000 via an antenna 1010. The processing system 1002 may be configured to perform processing functions for the communication device 1000, including processing signals received and / or to be transmitted by the communication device 1000.

[0077] The processing system 1002 includes a processor 1004 coupled to a computer readable medium / memory 1012 via a bus 1006. In some aspects, the computer readable medium / memory 1012 is configured to store a program that, when executed by the processor 1004, causes the processor 1004 to execute Figure 7 1004, or instructions (e.g., computer executable code) for performing the operations illustrated in the or other operations discussed herein for managing various techniques for CSI reporting between UEs via a sidelink channel. In certain aspects, the computer-readable medium / memory 1012 stores code 1014 for receiving one or more sidelink CSI-RSs targeted to a group of UEs including the UE from a first wireless device; code 1016 for receiving signaling indicating that the UE is selected to transmit a CSI report generated based on the one or more sidelink CSI-RSs; code 1018 for generating a CSI report based on the one or more sidelink CSI-RSs; and code 1020 for transmitting the CSI report to the first wireless device. In certain aspects, the processor 1004 has a circuit system configured to implement the code stored in the computer-readable medium / memory 1012. Processor 1004 includes a circuit system 1024 for receiving one or more sidelink CSI-RS targeting a UE group including the UE from a first wireless device; a circuit system 1026 for receiving signaling indicating that the UE is selected to transmit a CSI report generated based on the one or more sidelink CSI-RS; a circuit system 1028 for generating a CSI report based on the one or more sidelink CSI-RS; and a circuit system 1030 for transmitting the CSI report to the first wireless device.

[0078] The techniques described herein may be used for various wireless communication technologies, such as NR (e.g., 5G NR), 3GPP Long Term Evolution (LTE), Advanced LTE (LTE-A), Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), Time Division Synchronous Code Division Multiple Access (TD-SCDMA), and other networks. The terms "network" and "system" are often used interchangeably. A CDMA network may implement radio technologies such as Universal Terrestrial Radio Access (UTRA), cdma2000, and the like. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. cdma2000 covers IS-2000, IS-95, and IS-856 standards. A TDMA network may implement radio technologies such as Global System for Mobile Communications (GSM). OFDMA networks can implement radio technologies such as NR (e.g., 5G RA), Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDMA, etc. UTRA and E-UTRA are part of Universal Mobile Telecommunications System (UMTS). LTE and LTE-A are versions of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents from an organization named "3rd Generation Partnership Project" (3GPP). cdma2000 and UMB are described in documents from an organization named "3rd Generation Partnership Project 2" (3GPP2). NR is an emerging wireless communication technology under development.

[0079] In 3GPP, the term "cell" may refer to the coverage area of ​​a B node (NB) or a NB subsystem serving the coverage area, depending on the context in which the term is used. In NR systems, the term "cell" and BS, next-generation B node (gNB or g B node), access point (AP), distributed unit (DU), carrier, or transmission reception point (TRP) may be used interchangeably. The BS may provide communication coverage for macro cells, pico cells, femto cells, or other types of cells. A macro cell may cover a relatively large geographic area (e.g., a radius of several thousand meters) 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 residence) and may allow restricted access by UEs associated with the femto cell (e.g., UEs in a closed subscriber group (CSG), UEs of users in a residence, etc.). 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.

[0080] UE may also be referred to as a mobile station, terminal, access terminal, subscriber unit, station, customer premises equipment (CPE), cellular phone, smart phone, personal digital assistant (PDA), wireless modem, wireless communication device, handheld device, laptop computer, cordless phone, wireless local loop (WLL) station, tablet computer, camera, gaming device, netbook, smartbook, ultrabook, appliance, medical device or medical equipment, biometric sensor / device, wearable device (such as smart watch, smart clothing, smart glasses, smart wristband, smart jewelry (e.g., smart ring, smart bracelet, etc.)), entertainment device (e.g., music device, video device, satellite radio, etc.), transportation component or sensor, smart meter / sensor, industrial manufacturing equipment, global positioning system device, or any other suitable device configured to communicate via wireless or wired medium. Some UEs may be considered machine type communication (MTC) devices or evolved MTC (eMTC) devices. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc., which can communicate with a BS, another device (e.g., a remote device), or some other entity. A wireless node can provide connectivity for or to a network (e.g., a wide area network (such as the Internet) or a cellular network), for example, via a wired or wireless communication link. Some UEs may be considered Internet of Things (IoT) devices, which may be narrowband IoT (NB-IoT) devices.

[0081] In some examples, access to the air interface may be scheduled. A scheduling entity (e.g., BS) allocates resources for communication between some or all devices and equipment within its service area or cell. A scheduling entity may be responsible for scheduling, assigning, reconfiguring, and releasing resources for one or more subordinate entities. That is, for scheduled communications, subordinate entities utilize resources allocated by the scheduling entity. A base station is not the only entity that can be used as a scheduling entity. In some examples, a UE may act as a scheduling entity, and may schedule resources for one or more subordinate entities (e.g., one or more other UEs), and other UEs may utilize resources scheduled by the UE for wireless communication. In some examples, a UE may act as a scheduling entity in a peer-to-peer (P2P) network or in a mesh network. In a mesh network example, UEs may communicate directly with each other in addition to communicating with a scheduling entity.

[0082] Each method disclosed herein includes one or more steps or actions for implementing the method. These method steps and / or actions can be interchangeable with each other without departing from the scope of the claims. In other words, unless a specific order of steps or actions is specified, the order and / or use of specific steps and / or actions can be changed without departing from the scope of the claims.

[0083] 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, as well as any combination with multiple identical elements (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, and ccc, or any other ordering of a, b, and c).

[0084] As used herein, the term "determining" may encompass a wide variety of actions. For example, "determining" may include calculating, computing, processing, deriving, investigating, looking up (e.g., looking up in a table, a database, or another data structure), assuming, and the like. Also, "determining" may include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory), and the like. Also, "determining" may include resolving, selecting, choosing, establishing, and the like.

[0085] As used herein, unless explicitly indicated otherwise, "or" is intended to be interpreted in an inclusive sense. For example, "a or b" may include only a, only b, or a combination of a and b. As used herein, a phrase that refers to "at least one" or "one or more" of a list of items refers to any combination of those items, including individual members. For example, "at least one of a, b, or c" is intended to cover the following possibilities: only a, only b, only c, a combination of a and b, a combination of a and c, a combination of b and c, and a combination of a, b, and c.

[0086] The various illustrative components, logic, logic blocks, modules, circuits, operations, and algorithmic processes described in conjunction with the implementations disclosed herein may be implemented as electronic hardware, firmware, software, or a combination of hardware, firmware, or software, including the structures disclosed in this specification and their structural equivalents. This interchangeability of hardware, firmware, and software has been generally described in terms of their functionality and is illustrated in the various illustrative components, blocks, modules, circuits, and processes described above. Whether such functionality is implemented in hardware, firmware, or software depends on the specific application and the design constraints imposed on the overall system.

[0087] Various modifications to the implementations described in this disclosure may be apparent to those of ordinary skill in the art, and the universal principles defined herein may be applied to other implementations without departing from the spirit or scope of the disclosure. Thus, the claims are not intended to be limited to the implementations shown herein, but should be granted the widest scope consistent with the disclosure, the principles and novel features disclosed herein.

[0088] In addition, various features described in this specification in the context of separate implementations may also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation may also be implemented in multiple implementations separately or in any suitable subcombination. Thus, while features may be described above as functioning in a particular combination and even initially claimed as such, one or more features from a claimed combination may in some cases be removed from the combination, and a claimed combination may be directed to a subcombination, or a variation of a subcombination.

[0089] Similarly, although operations are depicted in a particular order in the accompanying drawings, this should not be understood as requiring such operations to be performed in the particular order shown or in a sequential order, or to perform all the illustrated operations 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 or a flow diagram. However, other operations that are not depicted may be incorporated into the example processes schematically illustrated. For example, one or more additional operations may be performed before, after, simultaneously or between any illustrated operations. In some environments, multitasking and parallel processing may be advantageous. In addition, the separation of various system components in the implementation described above should not be understood as requiring such separation in all implementations, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.

Claims

1. An apparatus for wireless communication by a first wireless device, comprising: at least one processor configured to: transmitting one or more sidelink channel state information (CSI) reference signals (CSI-RS) targeted to a group of user equipment (UE); requesting one or more CSI reports from one or more UEs selected from the group of UEs; as well as receiving one or more CSI reports from the selected one or more UEs, the CSI reports comprising coherent CSI information or non-coherent CSI information; as well as A memory is coupled to the at least one processor.

2. The apparatus of claim 1, wherein the at least one processor is configured to request time-staggered CSI reporting to a plurality of UEs in the group of UEs.

3. The apparatus of claim 1, wherein the at least one processor is configured to request simultaneous CSI reporting from a plurality of UEs in the group of UEs. 4 . The apparatus of claim 3 , wherein the simultaneous CSI reports are multiplexed via at least one of frequency division multiplexing (FDM) or space division multiplexing (SDM).

5. The apparatus of claim 1, wherein the at least one processor is configured to select the plurality of UEs in the group of UEs based on an ability of the first wireless device to receive CSI reports from the plurality of UEs using the same receive beam.

6. The apparatus of claim 1, wherein the at least one processor is configured to indicate the selected one or more UEs via sidelink control information (SCI).

7. The apparatus of claim 1, wherein the at least one processor is configured to select the one or more UEs based on at least one of: a radio resource control (RRC) configuration of a base station or dynamic signaling of a base station.

8. The apparatus of claim 1, wherein the at least one processor is further configured to: receiving downlink control information (DCI); and The one or more sidelink CSI-RS are transmitted in response to the DCI.

9. The apparatus of claim 8, wherein the DCI comprises a group DCI transmitted to the first wireless device and the group of UEs.

10. The apparatus of claim 8, wherein the DCI indicates that the first wireless device is to transmit the one or more sidelink CSI-RS and a UE selected to transmit a CSI report.

11. The apparatus of claim 1, wherein: A first one or more UEs in the selected UEs are configured to report a first subset of CSI parameters; and A second one or more of the selected UEs are configured to report a second subset of CSI parameters.

12. The apparatus of claim 11, wherein: The first CSI parameter subset is associated with coherent CSI information; and The second CSI parameter subset is associated with non-coherent CSI information.

13. An apparatus for wireless communication by a user equipment (UE), the apparatus comprising: at least one processor configured to: receiving, from a first wireless device, one or more sidelink channel state information (CSI) reference signals (CSI-RS) targeted to a group of UEs including the UE; receiving signaling indicating that the UE is selected to transmit a CSI report generated based on the one or more sidelink CSI-RSs; generating a CSI report based on the one or more sidelink CSI-RSs, the CSI report comprising coherent CSI information or incoherent CSI information; as well as transmitting the CSI report to the first wireless device; as well as A memory is coupled to the at least one processor.

14. The apparatus of claim 13, wherein the signaling indicates that the UE is to transmit the CSI report as one CSI report in a time-staggered set of CSI reports from selected UEs in the group of UEs.

15. The apparatus of claim 13, wherein the signaling indicates that the UE is to transmit the CSI report simultaneously with a CSI report of at least one other UE from the group of UEs.

16. The apparatus of claim 15, wherein simultaneous CSI reports are multiplexed via at least one of frequency division multiplexing (FDM) or space division multiplexing (SDM).

17. The apparatus of claim 15, wherein the at least one processor is configured to receive the signaling via sidelink control information (SCI).

18. The apparatus of claim 17, wherein the SCI configures the UE to report a subset of CSI parameters.

19. The apparatus of claim 18, wherein the subset of CSI parameters is associated with coherent CSI information or non-coherent CSI.

20. A method for wireless communication by a first wireless device, the method comprising: transmitting one or more sidelink channel state information (CSI) reference signals (CSI-RS) targeted to a group of user equipment (UE); requesting one or more CSI reports from one or more UEs selected from the group of UEs; as well as One or more CSI reports are received from the selected one or more UEs, the CSI reports including coherent CSI information or non-coherent CSI information.

21. The method of claim 20, wherein requesting the one or more CSI reports comprises at least one of requesting time-staggered CSI reports to multiple UEs in the group of UEs, and requesting simultaneous CSI reports to multiple UEs in the group of UEs.

22. The method of claim 21, wherein the simultaneous CSI reports are multiplexed via at least one of frequency division multiplexing (FDM) or space division multiplexing (SDM).

23. The method of claim 20, wherein the selected plurality of UEs in the group of UEs are selected based on an ability of the first wireless device to receive CSI reports from the plurality of UEs using the same receive beam.

24. The method of claim 20, wherein: A first one or more of the selected UEs are configured to report a first subset of CSI parameters associated with the coherent CSI information; and A second one or more of the selected UEs are configured to report a second subset of CSI parameters associated with non-coherent CSI.

25. A method for wireless communication by a user equipment (UE), the method comprising: receiving, from a first wireless device, one or more sidelink channel state information (CSI) reference signals (CSI-RS) targeted to a group of UEs including the UE; receiving signaling indicating that the UE is selected to transmit a CSI report generated based on the one or more sidelink CSI-RSs; generating a CSI report based on the one or more sidelink CSI-RSs, the CSI report comprising coherent CSI information or incoherent CSI information; as well as The CSI report is transmitted to the first wireless device.

26. The method of claim 25, wherein the signaling indicates that the UE is to transmit the CSI report as one of a set of time-staggered CSI reports from selected UEs in the group of UEs.

27. The method of claim 25, wherein the signaling indicates that the UE is to transmit the CSI report simultaneously with a CSI report of at least one other UE from the group of UEs.

28. The method of claim 27, wherein simultaneous CSI reports are multiplexed via at least one of frequency division multiplexing (FDM) or space division multiplexing (SDM).

29. The method of claim 27, wherein the signaling is signaled via sidelink control information (SCI).

30. The method of claim 29, wherein the SCI configures the UE to report a subset of CSI parameters associated with coherent CSI information or non-coherent CSI.

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