Channel state information feedback
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2026-01-23
- Publication Date
- 2026-08-13
Smart Images
Figure IB2026050659_13082026_PF_FP_ABST
Abstract
Description
[0001] CHANNEL STATE INFORMATION FEEDBACK
[0002] CROSS-REFERENCE TO RELATED APPLICATION
[0003]
[0001] This application claims priority from, and the benefit of, Great Britain Application No. 2501667.6, filed February 5, 2025, the contents of which are hereby incorporated by reference in their entirety.
[0004] TECHNOLOGICAL FIELD
[0005]
[0002] Examples of the disclosure relate to Channel State Information, CSI, feedback. Certain examples of the disclosure relate to apparatuses, methods, and computer programs for reporting CSI.
[0006] BACKGROUND
[0007]
[0003] Conventional apparatuses and procedures for CSI feedback are not always optimal. In some circumstances, it may be desirable to provide improved CSI feedback. In some circumstances, it may be desirable the reduce signaling overhead in CSI feedback. In some circumstances, it may be desirable to adapt one or more ranks that a calculation of CSI is based on. In some circumstances, it may be desirable to provide improved apparatuses, method and computer programs for calculating and reporting CSI.
[0008]
[0004] The listing or discussion of any prior-published document or any background in this specification should not necessarily be taken as an acknowledgement that the documentor background is part of the state of the art or is common general knowledge. One or more aspects / examples of the present disclosure may or may not address one or more of the background issues.
[0009] BRIEF SUMMARY
[0010]
[0005] The invention is defined in the independent claims.
[0011]
[0006] According to various, but not necessarily all, examples of the disclosure there are provided examples as claimed in the appended claims. Any examples and features described in this specification that do not fall under the scope of the independent claims are to be interpreted as examples useful for understanding various embodiments of the invention.
[0012]
[0007] According to various, but not necessarily all, examples of the disclosure there is provided a method, performed by an apparatus, wherein the method comprises:
[0013] a. receiving, from a network entity, information indicative of at least one set of one or more layers based at least in part on which at least one Channel State Information, CSI, parameter is to be calculated; b. calculating the at least one CSI parameter based at least in part on the at least one set of at least one or more layers; and
[0014] c. transmitting, to the network entity, information indicative of the at least one CSI parameter.
[0015]
[0008] According to various, but not necessarily all, embodiments there is provided an apparatus comprising a. at least one processor; and
[0016] b. at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to perform at least a part of one or more methods described herein.
[0009] According to various, but not necessarily all, examples of the disclosure there is provided a non-transitory computer readable medium, when executed by an apparatus, causes the apparatus to perform at least a part of one or more methods described herein.
[0017]
[0010] According to at least some examples of the disclosure there is provided an apparatus comprising means for performing at least part of one or more methods described herein.
[0018] [Oil] According to various, but not necessarily all, examples of the disclosure there is provided a computer program comprising instructions which, when executed by an apparatus, cause the apparatus to perform at least part of one or more methods described herein.
[0019]
[0012] According to various, but not necessarily all, examples of the disclosure there is provided:
[0020] a. a module, circuitry, a chipset comprising processing circuitry, a device and / or a system
[0021]
[0013] configured to (or comprising means for) perform(ing) at least a part of one or more methods described herein.
[0022]
[0014] The following portion of this ‘Brief Summary’ section describes various features that can be features of any of the examples described in the foregoing portion of the ‘Brief Summary’ section mutatis mutandis.
[0023]
[0015] In some but not necessarily all examples, the method further comprises:
[0024] a. receiving, from the network entity, information for configuring the apparatus to report the at least one CSI parameter based at least in part on the at least one set of at least one or more layers indicated through the information received from the network entity.
[0025]
[0016] In some but not necessarily all examples, the method further comprises:
[0026] a. receiving, from the network entity, information for configuring the apparatus to report at least one first CSI parameter, wherein the at least one first CSI parameter is calculated based at least in part on at least one first set of at least one or more layers.
[0027]
[0017] In some but not necessarily all examples, the at least one first set of at least one or more layers is determined by the apparatus based at least in part on at least one of the following:
[0028] a. at least one channel measurement;
[0029] b. at least one interference measurement;
[0030] c. at least one measurement of at least one reference signal, RS; or
[0031] d. at least one measurement of at least one Channel State Information, CSI, RS.
[0032]
[0018] In some but not necessarily all examples, the method further comprises:
[0033] a. determining the at least one set of one or more layers based at least in part on the information indicative of the at least one set of one or more layers;
[0034] b. determining the at least one set of one or more layers based at least in part on at least one configured rule;
[0035] c. determining the at least one set of one or more layers based on at least one pre-defined specification; ord. determining the at least one set of one or more layers based on determining that at least one condition has been met.
[0036]
[0019] In some but not necessarily all examples, determining the at least one set of one or more layers based at least in part on the received information comprises:
[0037] a. determining the at least one set of one or more layers based at least in part on the at least one first set of at least one or more layers.
[0038]
[0020] In some but not necessarily all examples, the method further comprises:
[0039] a. receiving, from the network entity, information for enabling the apparatus to determine the at least one set of one or more layers based at least in part on the at least one first set of at least one or more layers.
[0040]
[0021] In some but not necessarily all examples, determining the at least one set of one or more layers based at least in part on the received information comprises at least one of the following:
[0041] a. receiving the at least one set of one or more layers from the network entity;
[0042] b. receiving information indicative of one or more identifiers of the one or more layers from the network entity;
[0043] c. receiving information indicative of a rank indicator value.
[0044]
[0022] In some but not necessarily all examples, the at least one set of at least one or more layers differs at least in part to the at least one first set of at least one or more layers.
[0045]
[0023] In some but not necessarily all examples, the information for configuring the apparatus to report the at least one CSI parameter, or the information indicative of the at least one set of one or more layers, is at least one of the following:
[0046] a. comprised in the information for configuring the apparatus to report the at least one first CSI parameter;
[0047] b. associated with the information for configuring the apparatus to report the at least one first CSI parameter; or
[0048] c. based at least in part on the information for configuring the apparatus to report the at least one first CSI parameter.
[0049]
[0024] In some but not necessarily all examples, receiving the information for configuring the apparatus to report the at least one CSI parameter, or receiving the information indicative of the at least one set of one or more layers, comprises at least one of the following:
[0050] a. determining a CSI trigger state, wherein the CSI trigger state is associated with
[0051] i. information for configuring the apparatus to transmit the at least one CSI parameter, or ii.the information indicative of the at least one set of one or more layers; or
[0052] b. determining a CSI trigger state, wherein the CSI trigger state is associated with at least a part of:
[0053] i. information for configuring the apparatus to transmit the at least one CSI parameter, or ii.the information indicative of the at least one set of one or more layers.
[0025] In some but not necessarily all examples, transmitting, to the network entity, the information indicative of the at least one CSI parameter is based at least in part on determining whether at least one condition has been met.
[0054]
[0026] In some but not necessarily all examples, the at least one condition is based at least in part on at least one of the following:
[0055] a. the at least one set of one or more layers;
[0056] b. the at least one first set of at least one or more layers;
[0057] c. the at least one set of one or more layers differing at least in part from the at least one first set of at least one or more layers;
[0058] d. the at least one CSI parameter;
[0059] e. the at least one first CSI parameter; or
[0060] f. the at least one CSI parameter differing at least in part from the at least one first CSI parameter by a threshold amount.
[0061]
[0027] In some but not necessarily all examples, at least one of:
[0062] a. the information indicative of the at least one CSI parameter is transmitted in a CSI report;
[0063] b. at least a part of the information indicative of the at least one CSI parameter is transmitted in a CSI report;
[0064] c. the information indicative of the at least one CSI parameter is transmitted in a first part of a CSI report; or
[0065] d. the information indicative of the at least one CSI parameter is transmitted in a second part of a CSI report.
[0066]
[0028] In some but not necessarily all examples, at least one of:
[0067] a. the information indicative of the at least one first CSI parameter is transmitted in a first part of the CSI report;
[0068] b. the information indicative of the at least one first CSI parameter is transmitted in a second part of the CSI report;
[0069] c. the information indicative of the at least one first CSI parameter is transmitted in a first part of a CSI report which is different, at least in part, to the CSI report in which the information indicative of the at least one CSI parameter is transmitted; or
[0070] d. the information indicative of the at least one first CSI parameter is transmitted in a second part of a CSI report which is different, at least in part, to the CSI report in which the information indicative of the at least one CSI parameter is transmitted.
[0071]
[0029] In some but not necessarily all examples, the method further comprises:a. receiving, from the network entity, information indicative of at least one set of resources for at least one RS, and wherein the at least one CSI parameter is calculated based at least in part on at least one measurement of the at least one RS; or
[0072] b. receiving, from the network entity, information indicative of at least one set of resources for at least one channel, and wherein the at least one CSI parameter is calculated based at least in part on at least one measurement of the at least one channel.
[0073]
[0030] In some but not necessarily all examples, the at least one memory further stores instructions that, when executed by the at least one processor, cause the apparatus to perform at least one of the following: a. receiving, from the network entity, information indicative of one or more first resources for one or more first RSs; and wherein the at least one first CSI parameter is calculated based at least in part on one or more measurements of the one or more first RSs.
[0074]
[0031] In some but not necessarily all examples, at least one of:
[0075] a. the information indicative of at least one set of resources for at least one RS is comprised in or associated with information indicative of one or more first resources for one or more first RSs;
[0076] b. the at least one set of resources is based on the one or more first resources;
[0077] c. the at least one set of resources is the same as the one or more first resources;
[0078] d. the at least one set of resources is a subset of the one or more first resources; or
[0079] e. the at least one set of resources is different at least in part to the one or more first resources.
[0080]
[0032] In some but not necessarily all examples, the method further comprises:
[0081] a. transmitting, to the network entity, information indicative of the at least one first CSI parameter, wherein the information indicative of the at least one first CSI parameter and the information indicative of the at least one CSI parameter are comprised in:
[0082] i. a same uplink transmission or resource; or
[0083] ii. a separate uplink transmission or resource.
[0084]
[0033] In some but not necessarily all examples, the information indicative of the at least one CSI parameter comprises at least one of the following:
[0085] a. at least one Channel Quality Indicator, CQI;
[0086] b. at least one Precoding Matrix Indicator, PMI;
[0087] c. a Rank Indicator, Rl;
[0088] d. at least one Layer Indicator, LI;
[0089] e. at least one interference information;
[0090] f. at least one I nterference-plus-Noise information;
[0091] g. at least one power information;
[0092] h. at least one Reference Signal Received Power, RSRP
[0093] i. at least one Reference Signal Received Quality, RSRQ; orj. at least one Signal-to-l nterference-plus-Noise Ratio, SINR.
[0094]
[0034] In some but not necessarily all examples, the information indicative of the at least one CSI parameter comprises at least one of the following:
[0095] a. at least one value of the at least one CSI parameter;
[0096] b. at least one value based at least in part on:
[0097] c. at least one value of the at least one CSI parameter, and
[0098] d. at least one value of the at least one first CSI parameter;
[0099] e. at least one difference between:
[0100] f. at least one value of the at least one CSI parameter, and
[0101] g. at least one value of the at least one first CSI parameter; or
[0102] h. at least one value based at least in part on:
[0103] i. at least one function of at least one value of the at least one CSI parameter, and
[0104] j. at least one function of at least one value of the at least one first CSI parameter.
[0105]
[0035] In some but not necessarily all examples, the at least one set of one or more layers comprises or corresponds to at least one of the following:
[0106] a. at least one Rank Indicator, Rl;
[0107] b. at least one Multiple Input Multiple Output, MIMO, layer;
[0108] c. at least one transmission layer; or
[0109] d. at least one spatial element.
[0110]
[0036] While the above examples of the disclosure and optional features are described separately, it is to be understood that their provision in all possible combinations and permutations is contained within the disclosure. It is to be understood that various examples of the disclosure can comprise any or all the features described in respect of other examples of the disclosure, and vice versa. It is to be appreciated that any one or more or all the features, in any combination, may be implemented by / comprised in / performable by an apparatus, a method, a computer program, instructions and / or a system as desired, and as appropriate.
[0111]
[0037] The description herein of a function and / or action should additionally be considered also to disclose any means suitable for performing that function and / or action. Functions and / or actions described herein can be performed in any suitable way using any suitable method.
[0112]
[0038] The description of a function and / or action should additionally be considered also to disclose any instructions stored in at least one memory that, when executed by at least one processor, cause an apparatus to perform that function.
[0113] BRIEF DESCRIPTION
[0114]
[0039] Some examples will now be described with reference to the accompanying drawings in which:
[0115]
[0040] FIG. 1 shows an example of the subject matter described herein;
[0116]
[0041] FIG. 2 shows another example of the subject matter described herein;
[0042] FIG. 3 shows another example of the subject matter described herein;
[0117]
[0043] FIG. 4 shows another example of the subject matter described herein;
[0118]
[0044] FIG. 5 shows another example of the subject matter described herein;
[0119]
[0045] FIG. 6 shows another example of the subject matter described herein;
[0120]
[0046] FIG. 7 shows another example of the subject matter described herein;
[0121]
[0047] FIG. 8 shows another example of the subject matter described herein;
[0122]
[0048] FIG. 9 shows another example of the subject matter described herein;
[0123]
[0049] FIG. 10 shows another example of the subject matter described herein; and
[0124]
[0050] FIG. 11 shows another example of the subject matter described herein.
[0125]
[0051] The figures are not necessarily to scale. Certain features and views of the figures can be shown schematically or exaggerated in scale in the interest of clarity and conciseness. For example, the dimensions of some elements in the figures can be exaggerated relative to other elements to aid explication. Similar reference numerals are used in the figures to designate similar features. For clarity, all reference numerals are not necessarily displayed in all figures.
[0126]
[0052] In the description and drawings, a reference number without a subscript (e.g. 123) can be used as a generic reference to a feature or class / set of features. A reference number with a subscript (e.g. 123_1 ) can be used as a specific reference, e.g. to differentiate different instances of a feature or class / set of features. The subscript can comprise two digits including a first digit that labels a group of instances and a second digit that labels different instances in the group. A numerical type subscript index (e.g. 123_1 ) can be used to indicate a specific instance of a class / a member of a set; and a non-specific instance of the class (member of the set) can be referenced using the reference number with a variable type subscript index (e.g. 123J).
[0127] ABBREVIATIONS / DEFINITIONS
[0128]
[0053] BS Base Station
[0129]
[0054] CQI Channel Quality Indicator
[0130]
[0055] CRI CSI-RS Resource Indicator
[0131]
[0056] CSI Channel State Information
[0132]
[0057] CSI-RS Channel State Information Resource Signal
[0133]
[0058] DCI Downlink Control Information
[0134]
[0059] gNB Next generation NodeB, 5G / NR / next generation base station
[0135]
[0060] LI Layer Indicator
[0136]
[0061] MAC CE Medium Access Control Control Element
[0137]
[0062] MIMO Multiple Input Multiple Output
[0138]
[0063] NE Network Entity
[0064] NW Network
[0139]
[0065] PDCCH Physical Downlink Control Channel
[0140]
[0066] PDSCH Physical Downlink Shared Channel
[0141]
[0067] PMI Precoding Matrix Indicator
[0142]
[0068] PUCCH Physical Uplink Control Channel
[0143]
[0069] PUSCH Physical Uplink Shared Channel
[0144]
[0070] RAN Radio Access Network
[0145]
[0071] Rl Rank Indicator
[0146]
[0072] RRC Radio Resource Control
[0147]
[0073] RS Reference Signal
[0148]
[0074] RSRP Reference Signal Received Power
[0149]
[0075] RSRQ Reference Signal Received Quality
[0150]
[0076] SB Subband
[0151]
[0077] SI NR Signal-to-lnterference-plus-Noise Ratio
[0152]
[0078] UE User Equipment
[0153]
[0079] WB Wideband
[0154] DETAILED DESCRIPTION
[0155]
[0080] FIG. 1 schematically illustrates an example of a network 100 suitable for use with examples of the present disclosure. The network (which may be referred to as NW) comprises a plurality of network nodes 101 (which may be referred to as nodes of the network or network entities, NEs), including:
[0156]
[0081] terminal apparatuses 110 (which may be referred to as terminal nodes or User Equipment, UE);
[0157]
[0082] access apparatuses 120 (which may be referred to as access nodes, gNodeBs, gNBs, or Base Stations, BSs);
[0158]
[0083] one or more core network apparatuses 130 (which may be referred to as core nodes, core functions, core entities, core network entities - one core node / function / entity of which being an Access and Mobility Management Function, AMF).
[0159]
[0084] The terminal nodes 110 and access nodes 120 communicate with each other. The access nodes 120 communicate with the core nodes 130. One or more access nodes 120 may, in some but not necessarily all examples, communicate with each other. One or more core network nodes 130 may, in some but not necessarily all examples, communicate with each other.
[0160]
[0085] The network 100, in the example illustrates in FIG. 1, comprises a radio telecommunications network in which at least some of the terminal nodes 110 and access nodes 120 communicate with each other using transmission / reception of radio waves. In this regard, the network 100 comprises a Radio Access Network, RAN, such as a cellular network comprising a plurality of cells 122 each served by an access node 120. Theaccess nodes 120 comprise cellular radio transceivers. The terminal nodes 110 comprise cellular radio transceivers.
[0161]
[0086] In the example illustrated and discussed below, the network 100 is a New Radio, NR, network of the Third Generation Partnership Project, 3GPP, and its fifth generation, 5G, New Radio, NR, technology. It is to be appreciated, however, that in other examples, the network 100 may be a network beyond 5G, for example a next generation (i.e. sixth generation, 6G) Radio Network that is currently under development (i.e. an evolution of the NR network and its 5G technology).
[0162]
[0087] The interfaces between the terminal nodes 110 and the access nodes 120 are radio interfaces 124 (e.g., Uu interfaces). The interfaces between the access nodes 120 and one or more core nodes 130 are backhaul interfaces 128 (e.g., S1 and / or Next Generation, NG, interfaces).
[0163]
[0088] Depending on the exact deployment scenario, the access nodes 120 may be RAN nodes such as NG-RAN nodes. NG-RAN nodes may be gNodeBs, gNBs, that provide NG user plane and control plane protocol terminations towards the UE. The gNBs are connected by means of NG interfaces to a 5G Core, 5GC, not least for example to an Access and Mobility Management Function, AMF, by means of an NG Control Plane, NG-C, interface and to a User Plane Function, UPF, by means of an NG User Plane, NG-U, interface. The AMF may be connected by means of an N1 interface to the UE (not shown). The access nodes 120 may be interconnected with each other by means of Xn interfaces 126.
[0164]
[0089] The cellular network 100 may be configured to operate in licensed frequency bands, or unlicensed frequency bands (not least such as: unlicensed bands that rely upon a transmitting device to sense the radio resources / medium before commencing transmission, such as via a Listen Before Talk, LBT, procedure; and a 60GHz unlicensed band where beamforming may be required to achieve required coverage).
[0165]
[0090] The access nodes 120 may be deployed in an NG standalone operation / scenario. The access nodes 120 may be deployed in a NG non-standalone operation / scenario. The access nodes 120 may be deployed in a Carrier Aggregation, CA, operation / scenario. The access nodes 120 may be deployed in a Dual Connectivity, DC, operation / scenario, i.e., Multi Radio Access Technology - Dual Connectivity, MR-DC, or NR-DC. The access nodes 120 may be deployed in a Multi Connectivity, MC, operation / scenario.
[0166]
[0091] In such non-standalone / dual connectivity deployments, the access nodes 120 may be interconnected to each other by means of X2 or Xn interfaces, and connected to an Evolved Packet Core, EPC, by means of an S1 interface or to the 5GC by means of a NG interface.
[0167]
[0092] A terminal node 110, in addition to being capable of communicating (i.e. with other terminal nodes) via access nodes 120 of the network 100, may also be capable of and configured to communicate directly with one or more other terminal nodes. In this regard, the terminal node may be capable of and configured to perform device-to-device, D2D, communication - which may be referred to as Sidelink, SL, communication. Such D2D / SL communication may use a PC5 interface. PC5 refers to a reference point where the terminal node communicates directly with another terminal node over a direct channel (i.e. communication via anaccess node is not required). D2D communications may be short-range, network-less, direct communications. SL in New Radio (NR) is defined in 3GPP’s release 16 of 5G NR.
[0168]
[0093] In the example of FIG. 1 the core node 130 is shown as a single entity. In some examples the core node 130 could be distributed across a plurality of entities. For example, the core node 130 could be cloud based or distributed in any other suitable manner. The core node / core entities may provide one or more functions, not least such as: User Plane Function UPF, Session Management Function SMF, Policy Control Function PCF, Application Function AF, Location Management Function, LMF, and Access and Mobility Management Function, AMF.
[0169]
[0094] The access nodes 120 are network elements in the network responsible for radio transmission and reception in one or more cells 122 to or from the terminal nodes 110. The access nodes 120 are the network termination of a radio link. Each access node may be a Transmission Reception Point, TRP, or may host one or more TRPs.
[0170]
[0095] An access node 120 may be implemented as a single network equipment, or have a split architecture that is disaggregated / distributed over two or more access nodes, such as a Centralized / Control Unit, CU, a Distributed Unit, DU, a Remote Radio Head-end, RRH, using different functional-split architectures and different interfaces.
[0171]
[0096] The terminal nodes 110 are network elements in the network that terminate the user side of the radio link. They are devices allowing access to network services. Terminal node 110 functionalities may be performed also by Mobile Termination, MT, part of an Integrated Access and Backhaul, IAB, node. The terminal nodes 110 may be referred to as User Equipment, UE, mobile equipment, mobile terminals, or mobile stations.
[0172]
[0097] The term ‘User Equipment’ may be used to designate mobile equipment comprising means, such as a smart card, for authentication / encryption etc. such as a Subscriber Identity Module, SIM. A SIM / SIM card can be a memory chip, a module, or a Universal Subscriber Identity Module (USIM). In some examples, the term ‘User Equipment’ can be used to designate a location / position tag, a hyper / smart, a hyper / smart sensor, or a mobile equipment comprising circuitry embedded as part of the user equipment for authentication / encryption such as a software SIM.
[0173]
[0098] In the following description, a terminal node may be referred to simply as UE 110.
[0174]
[0099] In the following description, an access apparatus / access node to a RAN (e.g. a cellular network not least such as a 5G or 6G next generation RAN) may be referred to interchangeably as BS 120 or gNB 120.
[0175]
[0100] There now follows a brief discussion of the acquisition of Channel State Information, CSI.
[0176]
[0101] CSI acquisition, specifically the acquisition or estimation by a gNB of a downlink channel response, is effected via the receipt of CSI feedback from a UE. The CSI feedback from the UE may be used to assist the gNB in transmitting multiple layers (e.g. spatial layers or Multiple Input Multiple Output, MIMO, layers) to the UE on a downlink channel such as a Physical Downlink Shared Channel, PDSCH.
[0102] In such “downlink-derived” CSI acquisition, typically the UE would receive CSI-Reference Signal(s), RS, from the gNB on the downlink, DL, and the UE would estimate the downlink channel response, namely by performing measurements on the received CSI-RS. Based on the estimated DL channel, the UE would compute a feedback payload (i.e. a CSI payload) that typically comprises one or more of the following CSI components (which may also be referred to as CSI parameters) calculated by the UE based on the UE’s CSI measurements:
[0177]
[0103] a CSI-RS Resource Indicator, CRI, for indicating a preferred CSI-RS resource;
[0178]
[0104] a Rank Indicator, Rl, for indicating a number of spatial layers to assist the gNB in computing a number of spatial layers to use for transmission. The Rl is associated with, i.e. conditioned on / determined based on, the CRI;
[0179]
[0105] a Precoder Matrix Indicator, PMI, for indicating an optimal precoding matrix to use to assist the gNB in computing transmit precoding weights. The PMI is associated with, i.e. conditioned on / determined based, on the Rl; or
[0180]
[0106] a Channel Quality Indicator, CQI, for indicating a quality of a channel between the UE and gNB. the CQI is associated with, i.e. conditioned on / determined based on, the combination of CRI, Rl, and the PMI.
[0181]
[0107] CSI-RS are UE-specifically configured in RRC. However, CSI-RS can be shared among many UEs, i.e., more than 1 UE can be configured to receive the same Resource Elements (RE).
[0182]
[0108] In general, in order to save on DL resources, the gNB would try to use cell-specific or group-specific CSI-RS resources. A worst case of DL overhead is with UE specific CSI-RS where the DL overhead increases linearly with the number of UEs in the cell.
[0183]
[0109] CSI-RS has many functions in NR, e.g.:
[0184] CSI-RS for DL CSI acquisition
[0185] CSI-RS for beam management (BM) (based on Layer 1, L1, Reference Signal Received Power, RSRP)
[0186] CSI-RS fortracking (TRS)
[0187] UL CSI acquisition in reciprocity-based UL precoding.
[0188]
[0110] In some applications (e.g., CSI-RS for BM) CSI-RS are spatially beamformed into different directions.
[0189] [Hl] In general, a UE can be configured with up to 48 report configurations (CSI-ReportConfig) per component carrier (CC) / 4 per bandwidth part (BWP). One CSI resource config within 1 report configuration can be configured with up to 16 resource sets (aperiodic CSI) and 1 resource set (otherwise).
[0190]
[0112] In each CSI resource set, up to 64 Non-Zero-Power, NZP, CSI-RS resources and 1 NZP-CSI-RS resource up to 32 antenna ports.
[0191]
[0113] For CSI acquisition, the UE is configured also with a codebook type. Based on a measured channel across a CSI-RS resource, the UE can choose a favourite codeword from the specified codebook, i.e., precoding matrix indicator (PMI), along with channel quality indicator (CQI), and rank indicator (Rl). The UEcan also be configured to measure several CSI-RS resources (up to 8) within a resource set and report a favourite resource, i.e. via a CSI-RS resource indicator (CRI), along with: PMI, CQI and Rl which corresponds to the selected resource.
[0192]
[0114] Time domain:
[0193]
[0115] In the time domain, a CSI-RS resource may start at any OFDM symbol of a slot and it spans 1, 2, or 4 OFDM symbols depending on the number of ports configured.
[0194]
[0116] Likewise, also the UE measurement reporting of CSI can be also operated with periodic, semi-persistent, or aperiodic manner, which is so-called report types in NR report configuration. However, there are certain limitations, based on which:
[0195]
[0117] the UE periodic report can operate only based on the configured periodic CSI-RS resource-set, the UE semi-persistent report can operate based on both configured periodic and semi-persistent CSI-RS resource-set, and finally the UE aperiodic report can operate based on all periodic, semi-persistent, and aperiodic CSI-RS resource-set.
[0196]
[0118] Accordingly:
[0197]
[0119] the periodic CSI-RS resources can be used to generate any report type,
[0198]
[0120] the semi-persistent and periodic CSI-RS resources can be used to generate semi-persistent CSI reports, and
[0199]
[0121] the aperiodic CSI-RS can only be utilized only to generate the aperiodic report.
[0200]
[0122] There now follows a brief discussion of Frequency-granularity.
[0201]
[0123] The CSI Report Setting also defines which part of the bandwidth the CSI should correspond to, and in addition, what granularity in frequency the CSI should have. To accomplish this, the bandwidth of a BWP is divided into a number of subbands.
[0202]
[0124] All CSI-RS resources within one set are configured with same density and same nrofPorts, except for the NZP CSI-RS resources used for interference measurement.
[0203]
[0125] For semi-persistent and aperiodic CSI-RS, the actual triggering of CSI-RS transmission is per CSI-RS resource-set via either MAC CE or DCI. A resource set can be used as part of UE report configurations describing what is to be measured and, correspondingly, which measurement reporting are to be done by the UE. Specifically, if a CSI-RS resource-set is configured as ‘aperiodic’ by RRC, the CSI-RS resource set configuration includes a slot offset, aperiodicTriggeringOffset which defines the time interval between the triggering DCI and the CSI-RS transmission.
[0204]
[0126] For aperiodic CSI reporting, A-CSI reporting, up to 16 different reporting settings can be triggered with single DCI (e.g. for multiple component carriers) while semi-persistent CSI reporting, SP-CSI reporting, can trigger only one report setting with a single DCI. In order to trigger several SP-CSI reports (each in different slots), multiple DCIs are needed.
[0205]
[0127] There now follows a brief discussion of legacy CSI reporting framework.
[0128] In legacy CSI reporting framework, a UE is configured / indicated to calculate CSI report quantities / parameters (such as CRI, CQI, Rl, PMI, and / or LI) and report those in a CSI report sent on Physical Uplink Control Channel, PUCCH, or Physical Uplink Shared Channel, PUSCH.
[0206]
[0129] In legacy CSI reporting framework, the UE calculates CSI parameters (if reported) assuming the following dependencies between CSI parameters (if reported):
[0207] CQI shall be calculated based on / conditioned on the reported PMI, Rl and CRI
[0208] PMI shall be calculated based on / conditioned on the reported Rl and CRI
[0209] Rl shall be calculated based on / conditioned on the reported CRI.
[0210]
[0130] Hence, the UE determines an Rl, based on which CQI and PMI (if reported) are calculated. This means that the UE calculates some CSI parameters assuming a certain (determined) rank or number of transmission layers.
[0211]
[0131] However, for current CSI acquisition / feedback, the selection of Rl (based on which CSI parameters such as PMI and CQI are determined) is down to UE implementation, and therefore the gNB has no control over the Rl used by the UE in its computation of CQI and PMI.
[0212]
[0132] In legacy CSI reporting framework, the gNB is unable to control or adjust the rank or number of transmission layers that the UE uses in calculating CSI parameters (i.e. such as CQI and PMI) which are then reported to the gNB in CSI feedback.
[0213]
[0133] However, it would be useful for the gNB to have the flexibility / possibility to acquire additional information / knowledge from the UE(s) to facilitate link adaptation and more generally adaptation (or downgrading / upgrading) or allocation decisions to be made by the gNB. In this regard, it would be useful for the gNB to have the flexibility / possibility to control or adjust the rank or number of transmission layers that the UE uses in calculating CSI parameters that are reported to the gNB.
[0214]
[0134] As will be set out in further detail below, various examples of the present disclosure seek to enable a gNB to acquire additional information / knowledge to assist the network with potential adaptation / allocation decisions at the gNB.
[0215]
[0135] Various examples of the present disclosure seek to enable a gNB to control or adjust the rank or number of transmission layers that the UE uses in calculating CSI parameters that are reported to the gNB. For instance, the gNB may control / adjust / influence an Rl that is used by the UE in the calculated of the UE’s CSI feedback, i.e. the UE’s reported CSI, not least PMI and CQI.
[0216]
[0136] Advantageously, such CSI feedback (based on gNB controlled / selected Rl) can provide the gNB with feedback information for assisting the gNB, not least in link adaptation and more generally adaptation (or downgrading / upgrading) or allocation decisions to be made by the gNB.
[0217]
[0137] Advantageously, certain examples of the disclosure may thereby enable a UE to provide a gNB with improved / enhanced CSI information and feedback.
[0138] In this regard, as will be discussed in further detail below, in various examples of the disclosure, there is provided, for a UE that has been configured / indicated (or triggered) to report first CSI corresponding to or comprising at least one determined first rank (or number of transmission layers), the UE:
[0218]
[0139] obtains information for (enabling measurement and) reporting at least one second CSI corresponding to or assuming at least one second rank, wherein the first rank is different from the at least one second rank;
[0219]
[0140] calculates, at least partially based on the obtained information or on a configuration associated with the information, the at least one second CSI corresponding to the second rank, where each of the at least one second CSI comprises at least one CSI report quantity; and
[0220]
[0141] sends, to the network, at least one CSI report comprising at least part of the at least one second CSI corresponding the second rank.
[0221]
[0142] In effect, the UE receives information to determine at least one set of one or more (MIMO) layers. The at least one set of one or more layers may be dependent on:
[0222] a. a first rank [i.e. a rank previously determined by the UE (e.g. based on channel and / or interference) measurements] and / or
[0223] b. indicated by the network according to / through the received information.
[0224]
[0143] The UE then determines at least one CSI parameter based at least in part on [or associated with] the at least one set of one or more layers.
[0225]
[0144] FIG. 2 schematically illustrates an example of a procedure 200 and a signaling framework, between: a. a first apparatus 10_1 (in this example a UE 110), and
[0226] b. a second apparatus 10_2 (in this example a Network Entity, NE, namely a node of a RAN such as a gNB 120 serving the UE)
[0227]
[0145] for supporting the procedure. The procedure may be for CSI acquisition and / or CSI feedback.
[0228]
[0146] For the purposes of the following description of the FIG. 2, the first apparatus 10_1 shall be simply referred to as UE 110, and the second apparatus 10_2 shall be simply referred to as gNB 120.
[0229]
[0147] In block 201, the UE receives, from the gNB, information 301 which is indicative of at least one set of one or more layers 302, based at least in part on which at least one Channel State Information, CSI, parameter 303 is to be calculated.
[0230]
[0148] The at least one set of one or more layers may comprise or correspond to at least one of the following: a. at least one Rank Indicator, Rl;
[0231] b. at least one Multiple Input Multiple Output, MIMO, layer;
[0232] c. at least one transmission layer; or
[0233] d. at least one spatial element.
[0234]
[0149] The at least one spatial element may comprise or correspond to one or more of:
[0235] a. at least one RS port;
[0236] b. at least one antenna port;c. at least one beam;
[0237] d. at least one transmission configuration indicator state;
[0238] e. at least one antenna element;
[0239] f. at least one antenna panel or subpanel;
[0240] g. at least one spatial vector;
[0241] h. at least one spatial domain vector; or
[0242] i. at least one eigen vector.
[0243]
[0150] The at least one CSI parameter 303 may be, not least for example, any one or more of: a CSI component, a CSI report quantity, CQI, PMI, SI NR, RSRP, RSRQ (or a value / metric derived at least in part therefrom).
[0244]
[0151] The at least one set of one or more layers 302 indicated via the information 301 may be one or more MIMO / transmission layers, or an Rl, based on which CSI parameters (not least such as CQI and PMI) are to be calculated.
[0245]
[0152] The information 301 indicative of at least one set of one or more layers 302, may be information for indicating, to the UE, an Rl that the calculation of CSI parameters is to be based on.
[0246]
[0153] In block 202, the UE calculates the at least one CSI parameter 303 based at least in part on the at least one set of at least one or more layers 302.
[0247]
[0154] In block 203, the UE transmits, to the gNB, information 304 indicative of the at least one CSI parameter 303 calculated in block 202.
[0248]
[0155] The information 304 indicative of the at least one CSI parameter may comprise at least one of the following:
[0249] a. at least one Channel Quality Indicator, CQI;
[0250] b. at least one Precoding Matrix Indicator, PMI;
[0251] c. a Rank Indicator, Rl;
[0252] d. at least one Layer Indicator, LI;
[0253] e. at least one interference information;
[0254] f. at least one I nterference-plus-Noise information;
[0255] g. at least one power information (e.g. at least one signal power);
[0256] h. at least one Reference Signal Received Power, RSRP
[0257] i. at least one Reference Signal Received Quality, RSRQ; or
[0258] j. at least one Signal-to-l nterference-plus-Noise Ratio, SINR.
[0259]
[0156] The transmission of the information 304 may be, not least for example:
[0260] a. via Layer 1 Uplink Control Information, L1-UCI;
[0261] b. as MAC CE; or
[0262] c. through other means on PUCCH or PUSCH.
[0263]
[0157] In some examples, the UE receives, from the gNB, information for configuring the UE to report the at least one CSI parameter 303 based at least in part on the at least one set of at least one or more layers 302 indicated via the information 301 received from the gNB. Such reporting configuration information (e.g.CSI-ReportConfig) may comprise or correspond to a CSI report configuration for the reporting the information 304 (i.e. the information 304 indicative of the at least one CSI parameter 303).
[0264]
[0158] In some examples, the UE may have been configured (or triggered) to report CSI corresponding to or comprising at least one determined first rank (or number of transmission layers), i.e. at least one first rank determined in a conventional / legacy manner - namely based on / conditioned on measurements of a first set of CSI-RS resources that the UE has been configured with. Such CSI may be referred to herein simply as ‘first CSI’, and the at least one determined first rank (or number of transmission layers) may be referred to herein simply as ‘first Rl’. See for example FIG. 8 showing an example of first CSI of first CSI parameters 403 for a first rank 402.
[0265]
[0159] In some examples (not shown in FIG. 2, but shown in step 1 of FIG. 3), the UE receives, from the gNB, information for configuring the UE to report at least one first CSI parameter (e.g. first CSI such as CQI and PMI), wherein the at least one first CSI parameter is calculated based at least in part on at least one first set of at least one or more layers (e.g. first Rl). The first set of at least one or more layers may differ from the at least one set of at least one or more layers 302. The first set of at least one or more layers may be referred to simply as ‘first Rl’. The first Rl may be calculated in a conventional manner, i.e. as per legacy CSI acquisition / legacy CSI feedback behaviour (namely calculated based on / conditioned on measurements of a first set of CSI-RS resources). The at least one first CSI parameter, which is calculated based on the first Rl, may be referred to simply ‘first CSI’. The information for configuring the UE to report the first CSI may be referred to simply as ‘reporting configuration for first CSI’.
[0266]
[0160] The first Rl (which is calculated by the UE in a legacy / conventional manner) is to be compared and contrasted to the set of layers 302 which, rather than being calculated by the UE in the legacy manner, are instead indicated via the information 301 received in block 201. The set of layers 302 may be referred to herein simply as ‘second Rl’ 302 (however, it is to be appreciated that the set of layers 302 need not necessarily be an Rl, but could be one or more individual layers).
[0267]
[0161] The first CSI (which is calculated by the UE in a legacy manner - i.e. based on the conventionally calculated first Rl), is to be compared and contrasted to the at least one CSI parameter 303, which is calculated based on the second Rl . The at least one CSI parameter 303 may be referred to simply as ‘second CSI’ 303. In this regard, the first CSI is based on the first Rl, whereas the second CSI 303 is based on the second Rl 302 (which is indicated via the information 301 of block 201).
[0268]
[0162] The receipt of the information 301 enables the UE to determine, i.e. calculate or evaluate, the at least one set of one or more layers 302, based which CSI parameter(s) 303 is / are to be calculated. The determination of the at least one set of one or more layers 302 may be at least one of the following: a. based at least in part on the information 301 indicative of the at least one set of one or more layers 302 (for instance, the information may comprise a values of Rl or an identification of one or more layers that CSI parameters are to be calculated basd on);b. based at least in part on the at least one first set of at least one or more layers (in this regard, the at least one set of one or more layers [e.g. the second Rl 302] may depend on, relate to, or be a function of the first Rl. For instance, where the gNB is contemplating rank upgrading [or downgrading], the second Rl 302 may be evaluated as an integer number of Rl values higher [or lower] than the first Rl);
[0269] c. based at least in part on at least one rule (e.g. a rule that the UE has been configured with (for instance, the at least one set of one or more layers 302 may correspond to an Rl value that is an integer number of Rl values higher, or lower, than a first Rl);
[0270] d. based on at least one pre-defined specification (for instance, the at least one set of one or more layers 302 may correspond to a pre-determined Rl value or an integer number of Rl values higher, or lower, than a first Rl); or
[0271] e. based on determining that at least one condition has been met (wherein the at least one condition may be based on one or more calculated CSI quantities).
[0272]
[0163] The UE may transmit the information 304 based at least in part on determining whether at least one condition has been met (which could correspond to determining that an event has occurred). The at least one condition is based at least in part on at least one of the following:
[0273] a. the at least one set of one or more layers 302 (e.g. second Rl);
[0274] b. the at least one first set of at least one or more layers (e.g. first Rl);
[0275] c. the at least one set of one or more layers 302 differing at least in part from the at least one first set of at least one or more layers;
[0276] d. the at least one CSI parameter 303 (e.g. second CSI);
[0277] e. the at least one first CSI parameter (e.g. first CSI); or
[0278] f. the at least one CSI parameter 303 differing at least in part from the at least one first CSI parameter by a threshold amount (the threshold amount may be sig nalled / configured to the UE, pre-determined, or defined in the standard).
[0279]
[0164] The information 304 indicative of the at least one CSI parameter 303 may be information indicative of absolute values of the at least one CSI parameter 303 (i.e. second CSI) or relative values (i.e. values of the second CSI relative to the values of first CSI). In this regard, the information 304 indicative of the at least one CSI parameter 303 may comprise at least one of the following:
[0280] a. at least one value of the at least one CSI parameter 303;
[0281] b. at least one value based at least in part on:
[0282] i. at least one value of the at least one CSI parameter 303, and
[0283] ii. at least one value of the at least one first CSI parameter;
[0284] c. at least one difference between:
[0285] i. at least one value of the at least one CSI parameter 303, and
[0286] ii. at least one value of the at least one first CSI parameter; or
[0287] d. at least one value based at least in part on:i. at least one function of at least one value of the at least one CSI parameter 303, and ii. at least one function of at least one value of the at least one first CSI parameter.
[0288]
[0165] As will be discussed further below and shown with respect to FIGs. 4 to 9, in some examples, at least one of the follows occurs:
[0289]
[0166] the information 304 indicative of the at least one CSI parameter 303 (e.g. the second CSI) may be transmitted in a CSI report (e.g. such as is shown in FIGs. 4 to 9);
[0290]
[0167] a part of the information 304 indicative of the at least one CSI parameter 303 may be transmitted in a CSI report (e. g. such as is shown in FIGs. 4 and 6);
[0291]
[0168] the information 304 indicative of the at least one CSI parameter 303 is transmitted in a first part of a CSI report (e. g. such as is shown in FIG. 6 and 9);
[0292]
[0169] the information 304 indicative of the at least one CSI parameter 303 is transmitted in a second part of a CSI report (e.g. such as is shown in FIGs. 4, 7 and 9);
[0293]
[0170] the information 404 indicative of the at least one first CSI parameter 403 is transmitted in a first part of the CSI report (e.g. such as is shown in FIGs. 4, 5, 7 and 8);
[0294]
[0171] the information 404 indicative of the at least one first CSI parameter 403 is transmitted in a second part of the CSI report (e.g. such as is shown in FIGs. 4, 5, 7 and 8);
[0295]
[0172] the information 404 indicative of the at least one first CSI parameter 403 is transmitted in a first part of a CSI report which is different, at least in part, to the CSI report in which the information 304 indicative of the at least one CSI parameter 303 is transmitted (e.g. in this regard the first CSI 404 and second CSI 304 have own dedicated Part 1 CSI - such as is shown in FIGs. 5 and 6, as well as 8 and 9); or
[0296]
[0173] the information 404 indicative of the at least one first CSI parameter 403 is transmitted in a second part of a CSI report which is different, at least in part, to the CSI report in which the information 304 indicative of the at least one CSI parameter 303 is transmitted (e.g. in this regard the first CSI 404 and second CSI 304 have own dedicated Part 2 CSI - such as is shown in FIGs. 5 and 6, as well as 8 and 9).
[0297]
[0174] In some examples, the UE transmits, to the gNB, information 304 indicative of the at least one CSI parameter 303 and information indicative of the at least one first CSI parameter, wherein the information indicative of the at least one first CSI parameter and the information 304 indicative of the at least one CSI parameter 303 are comprised in:
[0298] a. a same uplink transmission (e.g. PUCCH / PUSCH) or resource; or
[0299] b. a separate uplink transmission or resource.
[0300]
[0175] In some examples, the UE receives, from the gNB, information indicative of at least one set of resources for at least one RS (e.g. CSI -RS resources, or resources for other RSs, such as DMRS or TRS) or at least one channel (e.g. a physical downlink channel such as PDSCH or PDCCH) wherein the at least one CSI parameter 303 is calculated based at least in part on at least one measurement of the at least one RS or (physical downlink) channel.
[0176] In some examples, the UE receives, from the gNB, information indicative of one or more first resources for one or more first RSs, or one or more first (physical downlink) channels, wherein the at least one first CSI parameter is calculated based at least in part on one or more measurements of the one or more first RSs or channels.
[0301]
[0177] In some examples, the information indicative of at least one set of resources for at least one RS (e.g. CSI -RS resources for the second CSI 304) or channel may be comprised in or associated with the information indicative of one or more first resources for one or more first RSs (e.g. CSI -RS resources for the first CSI) or one or more or first channels. In this regard:
[0302] a. the at least one set of resources (e.g. CSI -RS resources for the second CSI 304) may be based on the one or more first resources (e.g. CSI -RS resources for the first CSI);
[0303] b. the at least one set of resources (e.g. CSI -RS resources for the second CSI 304) may be the same as the one or more first resources (e.g. CSI -RS resources for the first CSI);
[0304] c. the at least one set of resources (e.g. CSI -RS resources for the second CSI 304) may be a subset of the one or more first resources (e.g. CSI -RS resources for the first CSI); or
[0305] d. the at least one set of resources (e.g. CSI -RS resources for the second CSI 304) may be different at least in part to the one or more first resources (e.g. CSI -RS resources for the first CSI).
[0306]
[0178] The UE may receive reporting configuration information (e.g. CSI-ReportConfig) for configuring the UE to (determine and) report the second CSI 303.
[0307]
[0179] The UE may receive reporting configuration information (e.g. CSI-ReportConfig) for configuring the UE to (determine and) report the first CSI.
[0308]
[0180] The reporting configuration information for the second CSI 303 may be based on or associated with another reporting configuration information, e.g. an earlier / previously received reporting configuration information. For instance, the reporting configuration information for the second CSI 303 may comprise or correspond to the reporting configuration for the first CSI. The earlier / previously received reporting configuration information may be considered to be a first CSI report configuration for reporting the first CSI (such first CSI corresponding to first CSI parameter(s) calculated in a conventional manner as per legacy CSI feedback based on a first Rl, i.e. a conventionally calculated Rl). The reporting configuration information for the second CSI may be considered to be a second CSI report configuration for reporting the second CSI (such second CSI corresponding to second CSI parameter(s) calculated based on the second Rl indicated via the information received in the block 201).
[0309]
[0181] The at least one first set of at least one or more layers (e.g. first Rl) may be determined by the UE based at least in part on at least one of the following:
[0310] a. at least one channel measurement;
[0311] b. at least one interference measurement;
[0312] c. at least one measurement of at least one reference signal, RS; ord. at least one measurement of at least one Channel State Information, CSI, RS.
[0313]
[0182] Whilst the examples above have discussed the evaluation of information indicative of a state / condition of a channel (i.e. CSI) based on the measurement on CSI-RS, it is to be appreciated that, in some examples, reference signals other than CSI-RS may be employed, not least for example: Demodulation Reference Signal, DMRS; or Tracking reference Signal, TRS.
[0314]
[0183] In some examples, rather than measuring reference signals, information indicative of a state / condition of a channel (i.e. CSI) could be determined from measurement(s) based on physical downlink channel(s) (such as PDSCH, PDCCH) transmissions or part(s) of such transmissions.
[0315]
[0184] In some examples, the UE may receive, from the gNB, information (e.g. a rule or condition) for enabling the UE to determine the at least one set of one or more layers (e.g. the second Rl) based at least in part on the at least one first set of at least one or more layers (e.g. the first Rl). Such information may include, not least for example, a value of the integer that is to be added to, or removed from the first Rl to form the second Rl. In some examples, such information may be signalled to the UE via RRC or MAC CE or DCI. In some examples such information may comprised in, or associated with, the information 301.
[0316]
[0185] In some examples, the UE’s determination of the at least one set of one or more layers 302 (e.g. the second Rl) based at least in part on the received information 301, comprises the UE receiving at least one of the following:
[0317] a. the at least one set of one or more layers from the gNB (e.g. receiving the value of the second Rl.
[0318] In this regard, the UE may receive information indicative of a rank indicator value, based on which the CSI parameter(s) 303 is / are to be calculated); or
[0319] b. information indicative of one or more identifiers of the one or more layers from the network entity (e.g. receiving identification of the layer(s) based on which the CSI parameter(s) 303 is / are to be calculated;
[0320]
[0186] The at least one set of at least one or more layers 302 (e.g. the second Rl) may differ, at least in part, to the at least one first set of at least one or more layers (e.g. the first Rl).
[0321]
[0187] The at least at least one CSI parameter 303 (e.g. the second CSI) that is to be [calculated and] reported may be: the same as, a subset of, or at least partly different from, the at least one first CSI parameter (e.g. the first CSI).
[0322]
[0188] The information 302 indicative of the at least one set of one or more layers (e.g. the second Rl) may be at least one of the following:
[0323] a. comprised in,
[0324] b. associated with, or
[0325] c. based at least in part on
[0326]
[0189] the information for configuring the UE to report the at least one first CSI parameter (i.e. the CSI report configuration for the first CSI).
[0190] The receiving, by the UE, of the information 301 indicative of the at least one set of one or more layers 302 (e.g. the second Rl) may comprise determining a CSI trigger state (e.g. via DCI or MAC CE), wherein the CSI trigger state is associated with at least a part of the information 301 indicative of the at least one set of one or more layers 302.
[0327]
[0191] Similarly, the information for configuring the UE to report the at least one CSI parameter (e.g. the CSI report configuration for the second CSI) may be at least one of the following:
[0328] a. comprised in,
[0329] b. associated with, or
[0330] c. based at least in part on
[0331]
[0192] the information for configuring the UE to report the at least one first CSI parameter (i.e. the CSI report configuration for the first CSI).
[0332]
[0193] Likewise, the receiving, by the UE, of the information for configuring the UE to report the at least one CSI parameter (e.g. the CSI report configuration for the second CSI) may comprise determining a CSI trigger state (e.g. via DCI or MAC CE), wherein the CSI trigger state is associated with at least a part of the information for configuring the apparatus to transmit the at least one CSI parameter (e.g. the CSI report configuration for the second CSI).
[0333]
[0194] FIG. 3 illustrates an example of a signaling diagram showing signaling (between a UE 110, a gNB 120) and a procedure 200 for CSI acquisition / feedback.
[0334]
[0195] In step 1, the UE is configured / indicated (or triggered) to report first CSI 404 corresponding to or comprising at least one determined first rank (or number of transmission layers) 402.
[0335]
[0196] In step 2 (which broadly corresponds to block 201 of FIG 2), the UE obtains information 301 for (enabling measurement and) reporting of at least one second CSI 304 that corresponds to, or assumes, at least one second rank 302, wherein the at least one second rank 302 depends on or relates to the first rank 402.
[0336]
[0197] In some examples, the UE’s obtaining of the information, for (enabling) reporting second CSI corresponding to at least one second rank, may correspond to the UE receiving information / configuration from the network, where such information may be comprised in or associated with a CSI report configuration (e.g. CSI-ReportConfig) corresponding to the at least one CSI report. For example, there may be an extended CSI report quantity or a dedicated or additional report quantity, e.g., under the CSI report configuration, for the purpose of (enabling) at least reporting second CSI corresponding to the at least one second rank.
[0337]
[0198] By way of an example, a CSI-ReportConfig may comprise an indication of which CSI quantities are to be reported, for instance:
[0338] a. CRI-CQI-PMI-RI-CQI2-RI2
[0199] Wherein: CRI, CQI, and PMI are all associated with / based on the first rank Rl
[0339] i. CQI 2, is associated with / based on the second rank RI2.
[0340]
[0200] It is to be noted that RI2 may not be reported to the network if the network already knows it. Accordingly, the report quantity may also be, for example, CRI-CQI-PMI-RI-CQI 2, where CQI2 is calculated based on RI2.
[0341]
[0201] By way of an example, a CSI-ReportConfig may comprise an indication of how the second rank is to be evaluated, e.g. how the second rank is based on the first rank, for instance:
[0342] a. Parameter_rank=integer (1)
[0343] b. RI2=RI-1
[0344]
[0202] In this regard, the second rank is rank value that is 1 less than the rank value of the first rank Rl.
[0345]
[0203] The UE may be specified or configured with CSI corresponding to or comprising the at least one second rank (e.g. CQI2 associated with RI2) may be included in Part 1 CSI or Part 2 CSI which include CSI corresponding to or comprising the first rank (e.g. CRI, CQI, and PMI associated with Rl). Alternatively, some of parts of that CSI could be included in Part 1 CSI and the remaining part in Part 2 CSI. In a variant, the CSI corresponding to or comprising the at least one second rank and the CSI corresponding to or comprising the first rank may each have dedicated Part 1 CSI and / or Part 2 CSI.
[0346]
[0204] By way of an example, a CSI-ReportConfig may comprise an indication of which CSI quantities are to be reported in which Part of a CSI report, for instance:
[0347] a. Part 1 (or element 1): CRI-CQI-PMI-RI
[0348] b. Part 2 (or element 2): CQI2-RI2 or CQI2
[0349] c. Parameter_rank=integer (1)
[0350] d. RI2=RI-1
[0351]
[0205] By way of an example, a CSI-ReportConfig may comprise an indication of a mapping between CSI trigger states and which Parts are to be reported in a CSI report, for instance:
[0352] a. Trigger state 1: Part i
[0353] b. Trigger state 2: Part 2
[0354] c. Trigger state 3: CSI report config 1 Part 1 and Part 2
[0355]
[0206] In some examples, the UE’s obtaining of the information, for (enabling) reporting second CSI corresponding to at least one second rank, may correspond to the UE receiving information such as CSI trigger state via DCI or MAC CE from the network, where this triggering state is associated with a CSI report configuration (or at least a part of) corresponding to the at least one CSI report and configuring the reporting of the second CSI corresponding to the at least one second rank.
[0356]
[0207] In some examples, the UE’s obtaining of the information, for (enabling) reporting second CSI corresponding to at least one second rank, may correspond to the UE determining that at least one condition is satisfied or at least one event has occurred. The at least one condition or event may be specified orconfigured / indicated (e.g., via RRC) to the UE. The at least one condition or event may be based on: the first CSI (which corresponds to or which comprises the first rank), the second CSI (which corresponds to or which comprises the second rank), or the first and the second CSI. One example of such condition or event would be that the second CQI or delta CQI becomes greater, or alternatively lower, than a certain threshold.
[0357]
[0208] In step 3, the UE determines, at least partially based on the obtained information 301, the at least one second rank 302.
[0358]
[0209] The at least one second rank 302 may depend on, relate to, or be a function of the first rank 42. The UE may determine the at least one second rank 302 based on the obtained information 301 or based on a configuration associated with the information 301.
[0359]
[0210] The UE may be provided with the at least one second rank, or with at least one integer or information (such as rule) for determining a respective at least one second rank. This may be pre-determined (e.g. specified / defined in the standard, such that the UE is pre-configured with the at least one second rank or information for determining the at least one second rank), or the UE may be configured to be comprised in or associated with a CSI report configuration.
[0360]
[0211] Alternatively, or additionally, the UE may be specified or configured / indicated (e.g., via RRC or MAC CE or DCI) how the at least one second rank depends on, relates to, or is a function of the first rank.
[0361]
[0212] The UE may determine the at least one second rank based on: specifications, at least one rule, and / or based on an indication (e.g., via RRC, MAC CE or DCI) from the network.
[0362]
[0213] In some examples, the at least one second rank may be equal to the first rank minus (-) a specified or configured integer (e.g. denoted x, where x=1 for example). For instance, ifthe first rank were determined to be Rl = 3, the second rank could be calculated as Rl - x = 3 - x.
[0363]
[0214] In some examples, the at least one second rank may be equal to the first rank plus (+) a specified or configured integer (e.g. denoted x, where x=1 for example). For instance, if the first rank were determined to be Rl = 2, the second rank could be calculated as Rl + x = 2 + x.
[0364]
[0215] In some examples, the at least one second rank may be configured via indication to be a static value, wherein the at least one second rank is ( / are) reported when the first rank is not equal to it. This may be done for use cases where it would be desirable to control / fix the second rank, for instance use cases such as where one or more of the following is required: accurate CQI / PMI for forced rank 1 transmissions of Signaling Radio Bearers, SRBs; Voice over IP, VoIP; high reliability, or Ultra-Reliable Low Latency Communications, URLLC, traffic.
[0365]
[0216] In some examples, the at least one second rank may be configured via indication, wherein the at least one second rank is configured to be at least one of the set {2,4, .. ,,2*ceil(n / 2 - 1)}, wherein the first rank value is n and greater than 2. In other words, the at least one second rank may be calculated based on the first rank (here denoted n) using 2*ceil(n / 2 - 1).
[0217] In some examples, the at least one second rank may be dynamically downgraded, e.g. to rank 2 when rank 3 or rank 4 is reported (i.e. as the first rank) and the UE is Multi-User Multiple Input Multiple Output, MU-MIMO, paired or is Single-User Multiple Input Multiple Output, SU-MIMO, with high Block Error Rate, BLER. Extending this, when the reported rank (i.e. the first rank) is 5, then the value of the second rank can be defined as rank 2 (single beam) or rank 4 (2 beams) for MU-MIMO or SU-MIMO respectively.
[0366]
[0218] In some examples, the UE’s obtaining of the information, for (enabling) reporting second CSI corresponding to at least one second rank, may correspond to the UE obtaining information for (enabling) reporting at least one second CSI corresponding to a certain at least one MIMO layer (or specifically, to a certain at least one MIMO / transmission layer). For example, in case of first rank (or first Rl (rank indicator)) is 2, the UE may be specified or configured / indicated (e.g., through CSI report configuration or through CSI triggering state) to report second CSI, such as SINR or CQI or delta CQI or RSRP or RSRQ or power etc., which corresponds to an additional layer which would here correspond to layer 3 - assuming that Rl=2 corresponds to the first two (best) layers.
[0367]
[0219] As another example, in case of first rank is 2, the UE may be specified or configured / indicated (e.g., through CSI report configuration or through CSI triggering state) to report second CSI, such as SINR or CQI or delta CQI or RSRP etc., which corresponds to two additional layers which would here correspond to layers 3 and 4 - assuming that Rl =2 corresponds to the first two (best) layers.
[0368]
[0220] As yet another example, the UE may be specified or configured / indicated to report the at least second CSI for a fixed at least one rank (e.g. second rank = Rank 2; third rank = Rank 3). The second CSI for the second rank is reported if the first rank is different from it. Similarly, the third CSI for the third rank is reported if the first rank is different from it, etc.
[0369]
[0221] In some examples, when the at least second rank is less than the first rank, the precoder for the second rank may be implicitly derived from the precoder of the first rank. In this case, the PMI for the second rank is not required to be reported. For example, the precoder coefficients of the second rank may be the first R columns of the precoder coefficients indicated by the first rank’s PMI.
[0370]
[0222] In some examples, when the rank of the second CSI is of a higher value than that of the first CSI’s rank, the second PMI may be used to indicate the precoding matrix coefficients only for the additional layer(s), i.e. the first L layers use the precoder indicated by the first CSI’s PMI.
[0371]
[0223] In step 4 (which broadly corresponds to block 202 of FIG 2), the UE calculates, at least partially based on the obtained information 301, or on a configuration associated with the information, the at least one second CSI 304 corresponding to the second rank 302. Each of the at least one second CSI 304 comprises at least one CSI report quantity 303.
[0372]
[0224] In step 5, the UE determines to report at least one CSI report comprising the at least one second CSI 304 corresponding the at least one second rank 302. The at least one CSI report may also comprising the first CSI 404 corresponding the first rank 402.
[0225] The first CSI 404 may comprise at least one of:
[0373] a. at least one first CQI (Channel Quality Indicator),
[0374] b. a first Rl (Rank Indicator) 402,
[0375] c. at least one first PMI (Precoding / precoder Matrix Indicator(s), which can be subband and / or wideband)),
[0376] d. first LI (Layer Indicator),
[0377] e. first RSRP (Reference Signal Received Power),
[0378] f. first RSRQ (Reference Signal Received Quality), or
[0379] g. first SINR (Signal-to-lnterference-plus-Noise Ratio).
[0380]
[0226] A second CSI 304_x (of the at least one second CSI 304_n) may comprise at least one of: a. a second CQI, or a delta CQI which corresponds to a difference with respect to the at least one first CQI (e.g., first CQI - second CQI, or second CQI - first CQI),
[0381] b. a second PMI(s) (subband or wideband), or a delta PMI which corresponds to a difference (or differential value) with respect to the at least one first PMI,
[0382] c. a second RSRP, or a delta RSRP which corresponds to a difference (or differential value) with respect to the first RSRP,
[0383] d. a second RSRQ, or a delta RSRQ which corresponds to a difference (or differential value) with respect to the first RSRQ,
[0384] e. a second SINR, or delta SINR which corresponds to a difference (or differential value) with respect to the first SINR,
[0385] f. a function of first CQI and second CQI,
[0386] g. a function of the first RSRP and the second RSRP, or
[0387] h. a function of the first SINR and the second SINR, etc.
[0388]
[0227] In step 6, the UE sends, to the gNB, the at least one CSI report comprising at least part of the at least one second CSI 304 corresponding the second rank 302. The at least one CSI report may also comprising the first CSI 404 corresponding the first rank 402.
[0389]
[0228] The at least one second CSI 304 may be reported as L1-UCI, or as MAC CE, or through other means, or on PUCCH and / or PUSCH.
[0390]
[0229] The UE may provide indication indicative whether the UE is reporting, e.g., in the at least one CSI report, the second CSI or part of the second CSI. This may be seen as an (implicit) indication that (or whether) the at least one condition is satisfied or the at least one event has occurred.
[0391]
[0230] In step 7, the gNB may use the received at least one CSI report to determine a rank for transmission(s) to the UE. In this regard, the gNB may select, from among the reported ranks, a rank for transmission. The selection of the rank may be based at least in part on the at least one CSI report and also based on any of: bearer characteristics, traffic load, link adaptation characteristic, or other criteria.
[0231] In step 8, the gNB may transmit control information or data under the selected rank, optionally with the at least one of:
[0392] a. precoding,
[0393] b. beamforming,
[0394] c. Modulation and Coding Scheme, MCS, or
[0395] d. transmit power
[0396]
[0232] determined based on the received CSI report for the selected rank.
[0397]
[0233] At least some embodiments of this invention may apply or may be valid for cases where the UE is configured or scheduled with a single codeword or transport block, or alternatively with more than one codeword or transport block; each codeword or transport block being mapped to one or more layers (and / or ports).
[0398]
[0234] In some embodiments, the first rank may correspond to: a first (MIMO) layer, or a layer set (which comprises one or more layers), or a first RS port, or RS port set (which comprises one or more RS ports); and the second rank may correspond to: a second layer, or layer set (which comprises one or more layers), or a second RS port, or RS port set (which comprises one or more RS ports).
[0399]
[0235] In some embodiments, the first rank may correspond to: a first MIMO element, or first MIMO element set; and the second rank may correspond: to a second MIMO element.
[0400]
[0236] The UE may be configured or indicated by the network to report information indicative of a metric value corresponding to (or associated with) at least one MIMO element or MIMO element set.
[0401]
[0237] Alternatively, or additionally, the UE may be configured or indicated by the network to calculate and report information indicative of a metric value difference corresponding to at least two MIMO elements or two MIMO element sets.
[0402]
[0238] Alternatively, or additionally, the UE may be configured or indicated by the network to report information indicative of a metric value difference among or across multiple MIMO elements.
[0403]
[0239] The metric value may correspond to: RSRP (value), RSRQ (value), SI NR (value), power (value), etc.
[0404]
[0240] The metric value difference may correspond to: RSRP difference, RSRQ difference, SINR difference, power difference (e.g., such as signal power difference), etc. The metric value difference may correspond to an absolute difference.
[0405]
[0241] The metric value of a MIMO element set may be calculated as a linear average, or as any other averaging function or other function in general, of the metric values of all or some of the MIMO elements in the set.
[0406]
[0242] The metric value difference of a MIMO element set may be calculated as the difference between the maximum and the minimum metric values considering the value of each MIMO element in the set.
[0407]
[0243] The metric value difference between two MIMO element sets may correspond to the difference between an average value of the first set and an average value of the second set.
[0244] The metric value difference between two MIMO element sets may correspond to the maximum value or minimum value of the difference between metric value difference of the first set and metric value difference of the second set.
[0408]
[0245] It should be noted that, although the focus has been mainly on two element sets, the above aspects could be extended to cases with more than two element sets.
[0409]
[0246] The UE may be configured / indicated, e.g., through or as part of CSI report configuration, to report the metric value or metric value difference per sub-band (per part or chunk of frequency allocation) or to report it as wideband.
[0410]
[0247] The UE may be configured / indicated, such as through or part of the CSI report configuration, to report the metric value or metric value difference per at least one (serving) cell or carrier or component carrier or bandwidth part.
[0411]
[0248] The reporting of the metric value or the metric value difference may be configured as part of a CSI configuration such as a CSI report configuration.
[0412]
[0249] The reporting of the metric value or the metric value difference may be configured as part of a report quantity included in a CSI report configuration.
[0413]
[0250] The reporting of the metric value or metric value difference may be associated with a CSI trigger state.
[0414]
[0251] A MIMO element may comprise one or more of: at least one MIMO (or transmission) layer (or at least one RS layer), at least one RS port, at least one beam, at least one spatial (domain) vector. Note that spatial element and MIMO element may be used interchangeably.
[0415]
[0252] It should be noted that a beam or a spatial vector may be associated or mapped to one or more layers or (RS) ports.
[0416]
[0253] The RS may be: CSI-RS, DMRS, and / or TRS, or any other type of reference signal, etc.
[0417]
[0254] Examples of the disclosure, not least such as those discussed above with reference to FIGs 2 and 3, may thereby provide an enhanced CSI framework which advantageously enables / provides a more efficient rank upgrading or downgrading, or more generally rank adaptation, at the network side.
[0418]
[0255] Efficient dynamic (i.e. slot-by-slot) rank adaptation may be used to provide one or more of the following advantages:
[0419]
[0256] improve link adaptation BLER performance or spectral efficiency or both
[0420] a. gNB / network can dynamically reduce the rank of the UE when there is a high BLER at low MCS region to achieve a target BLER of the UE
[0421] b. gNB / network can dynamically increase the rank of the UE when there is low BLER at high MCS region to increase throughput
[0422]
[0257] simultaneously support different radio bearer types with differing Quality of service, QoS, requirementsa. gNB / network can dynamically downgrade the rank when a signalling, VoIP, high reliability, or URLLC bearer is sent at the slot to improve the bearer’s reliability
[0423]
[0258] improve cell throughput under an instantaneous offered traffic load
[0424] a. gNB / network can momentarily adjust the rank to provide more available radio resources to other UEs
[0259] provide greater flexibility to retransmissions with adaptive incremental redundancy
[0425] a. gNB / network can decrease the rank under Adaptive Interference Rejection, IR, to improve residual BLER or increase the rank under Adaptive IR to improve spectral efficiency
[0426]
[0260] achieve network energy saving
[0427] a. transmit power can be reduced without sacrificing reliability by changing the rank based on the amount of data to be transmitted and appropriately adjusting the power spectral density of the allocated RBs.
[0428]
[0261] In addition, examples of the disclosure may allow probing or acquiring of CSI corresponding to specific / individual transmission / MIMO layer(s) which are not part of a rank indicator provided by the UE.
[0429]
[0262] Yet furthermore, examples of the disclosure may enable acquiring metric value difference between at least two MIMO elements or element(s) sets such as two MIMO layers or at least two MIMO layers set, or between at least two RS ports or at least two RS port sets, or between at least two beams / vectors (at the UE) etc. Such additional information would allow the gNB to make suitable and adaptive allocations of resources (such as of time, frequency, spatial, and / or power resources).
[0430]
[0263] The blocks illustrated in FIGs. 2 and 3 can represent actions in a method, functionality performed by an apparatus, and / or sections of instructions, program or code. The illustration of a particular order to the blocks does not necessarily imply that there is a required or preferred order for the blocks and the order and arrangement of the block may be varied. Furthermore, it may be possible for some blocks to be omitted.
[0431]
[0264] It will be understood that each block and combinations of blocks illustrated in FIGs. 2 and 3 as well as the further functionality described herein, can be implemented by various means, such as hardware, firmware, and / or software including one or more computer program instructions. For example, one or more of the functions described above can be performed by a duly configured apparatus (such as an apparatus [as shown in FIG. 10] comprising means for performing the above described functionality). One or more of the functions / functionality described above can be embodied by a duly configured computer program (such as a computer program [as shown in FIG. 11] comprising computer program instructions which embody the functions / functionality described above and which can be stored by a memory storage device and performed by a processor).
[0432]
[0265] As will be appreciated, any such computer program instructions can be loaded onto a computer or other programmable apparatus (i.e. hardware) to produce a machine, such that the instructions when performed on the programmable apparatus create means for implementing the functions / functionality specified in the blocks. These computer program instructions can also be stored in a computer-readablemedium that can direct a programmable apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the blocks. The computer program instructions can also be loaded onto a programmable apparatus to cause a series of operational actions to be performed on the programmable apparatus to produce a computer-implemented process such that the instructions which are performed on the programmable apparatus provide actions for implementing the functions / functionality specified in the blocks.
[0433]
[0266] FIG. 4 schematically illustrates an example of encoding / mapping of the CSI corresponding to the second rank, namely CQI(R-1) 303 for RI-1 302. Here the CSI corresponding to the second rank is included in the same CSI part 2 as for the CSI corresponding to the first rank, namely PMI(WB, SB) 403_3 for Rl 402. WB and SB refer to wideband and sub-band respectively, and (CQI (RI-1) corresponds to CQI of rank RI-1 (i.e. CQI associated with / based on the second rank which, in the example shown, is 1 less than the value of the first rank).
[0434]
[0267] Alternatively, CQI (R-1) could be reported in CSI part 1. It is noted that the CQI(R-1) 303 for RI-1 302 may be reported as absolute value(s), or alternatively as differential value(s) i.e. with respect to CQI 403_2 for Rl 402.
[0435]
[0268] It is to be noted that the UE need not necessarily include the at least one second rank in the CSI report. This is because, the gNB either configured the at least one second rank or configured the UE with a rule / way to determine the at least one second rank, e.g. based on the first rank. In this regard, the gNB would know, a priori, what the at least one second rank is. This may also be valid for other CSI quantities which may be common between the CSI corresponding to the first rank and the CSI corresponding to the at least one second rank. Hence, any such common CSI quantities need not necessarily be additionally reported for the CSI corresponding to the second rank - thereby reducing an amount of information / data to be transmitted.
[0436]
[0269] FIGs. 5 and 6 schematically illustrate another example of encoding / mapping of the CSI corresponding to the second rank. Here the CSI corresponding to the second rank, namely CQI 303 for Rl-1 302, has a dedicated part 1 CSI. The CQI for RI-1 may be reported as absolute value(s) or differential value(s).
[0437]
[0270] FIG. 7 schematically illustrates yet another example of encoding / mapping of the CSI corresponding to the second rank (RI2 = RI-1). This example is broadly similar to that of FIG. 4, except that, rather than a single parameter / component of CSI corresponding to the second rank (namely CQI 303 for RI-1 302) being in CSI part 2, instead two parameters / components of CSI corresponding to the second rank are included in CSI part 2, namely: CQI 303_1 for RI-1 302 and also PMI 303_2 for RI-1 302.
[0271] FIGs. 8 and 9 schematically illustrate yet another example of encoding / mapping of the CSI corresponding to the second rank (RI2). This example is somewhat similar to that of FIGs. 5 and 6, except that CSI corresponding to the second rank, namely CQI 303_1 for RI2302 and PMI 303_2 for RI2302, have dedicated Part 1 CSI and Part 2 CSI respectively.
[0438]
[0272] The signaling diagrams of FIGs. 2 and 3 can be considered to illustrate a plurality of methods, in the sense that each signaling diagram can be considered to illustrate one or more actions, processes or procedures performed by / at a plurality of actors / entities (e.g. UE 110 and gNB 120). The signaling diagrams can therefore be considered to illustrate a plurality of individual methods performed by each respective individual actor / entity of the plurality of the actors / entities.
[0439]
[0273] The above described component blocks and step (e.g. of the signaling diagrams) are functional and the functions, along with the further functions / functionalities described above, can be performed by a single physical entity (such as an apparatus as is described with reference to FIG. 10, which may be embodied in / as a UE or gNB). The functions described can also be implemented by a computer program (such as is described with reference to FIG. 11 , which may be executed by a processor of a UE, or gNB).
[0440]
[0274] FIG. 10 schematically illustrates a block diagram of an apparatus 10 for performing the methods, processes, procedures and signaling described in the present disclosure, not least as illustrated in FIGs. 2 and 3. In this regard the apparatus can perform the roles of an entity (such as: UE or gNB) in the illustrated and above described methods.
[0441]
[0275] The component blocks of FIG. 10 are functional and the functions described can be performed by a single physical entity, not least such as a UE or gNB.
[0442]
[0276] The apparatus comprises a controller 11, which could be provided within a device / entity, not least such as a UE or gNB.
[0443]
[0277] The controller 11 can be embodied by a computing device, not least such as those mentioned above. In some, but not necessarily all examples, the apparatus can be embodied as a chip, chip set, circuitry or module, i.e. for use in any of the foregoing. As used here ‘module’ refers to a unit or apparatus that excludes certain parts / components that would be added by an end manufacturer or a user.
[0444]
[0278] Implementation of the controller 11 can be as controller circuitry. The controller 11 can be implemented in hardware alone, have certain aspects in software including firmware alone or can be a combination of hardware and software (including firmware).
[0445]
[0279] The controller 11 can be implemented using instructions that enable hardware functionality, for example, by using executable instructions, program or code 14 in a general-purpose or special-purpose processor 12 that can be stored on a computer readable storage medium 13, for example memory, or disk etc, to be executed by such a processor 12.
[0446]
[0280] The processor 12 is configured to read from and write to the memory 13. The processor 12 can also comprise an output interface via which data and / or commands are output by the processor 12 and an inputinterface via which data and / or commands are input to the processor 12. The apparatus can be coupled to or comprise one or more other components 15 (not least for example: a radio transceiver, sensors, input / output user interface elements and / or other modules / devices / components for inputting and outputting data / commands).
[0447]
[0281] The memory 13 stores instructions such as a computer program or code 14 comprising such instructions (e.g. computer program instructions, or computer program code) that controls the operation of the apparatus 10 when loaded into the processor 12. The instructions, program or code 14 provide the logic and routines that enables the apparatus to perform the methods, processes and procedures described in the present disclosure and illustrated in FIGs. 2 and 3. The processor 12 by reading the memory 13 is able to load and execute the instructions, program or code 14.
[0448]
[0282] The instructions may be comprised in a computer program, a non-transitory computer readable medium, a computer program product, a machine readable medium. The term “non-transitory,” as used herein, is a limitation of the medium itself (i.e. tangible, not a signal) as opposed to a limitation on data storage persistency (e.g. RAM vs. ROM). In some but not necessarily all examples, the computer program instructions may be distributed over more than one computer program.
[0449]
[0283] Although the memory 13 is illustrated as a single component / circuitry it can be implemented as one or more separate components / circuitry some or all of which can be integrated / removable and / or can provide permanent / semi-permanent / dynamic / cached storage.
[0450]
[0284] Although the processor 12 is illustrated as a single component / circuitry it can be implemented as one or more separate components / circuitry some or all of which can be integrated / removable. The processor 12 can be a single core or multi-core processor.
[0451]
[0285] The apparatus can include one or more components for effecting the methods, processes and procedures described in the present disclosure and illustrated in FIGs. 2 and 3. It is contemplated that the functions of these components can be combined in one or more components or performed by other components of equivalent functionality. The description of a function should additionally be considered to also disclose any means suitable for performing that function.
[0452]
[0286] Where a structural feature has been described, it can be replaced by means for performing one or more of the functions of the structural feature whether that function orthose functions are explicitly or implicitly described.
[0453]
[0287] Although examples of the apparatus have been described above in terms of comprising various components, it should be understood that the components can be embodied as or otherwise controlled by a corresponding controller or circuitry such as one or more processing elements or processors of the apparatus. In this regard, each of the components described above can be one or more of any device, means or circuitry embodied in hardware, software or a combination of hardware and software that is configured to perform the corresponding functions of the respective components as described above.
[0288] The apparatus can, for example, be: a user equipment, base station or network node of a mobile cellular telecommunication system. The apparatus can be embodied by a computing device, not least such as those mentioned above. However, in some examples, the apparatus can be embodied as a chip, chip set, circuitry or module, i.e. for use in any of the foregoing.
[0454]
[0289] In one example, the apparatus is embodied on a client device, a UE, a mobile cellular telephone, a hand held portable electronic device, a mobile communication device, a wearable computing device or a personal digital assistant, that can additionally provide one or more aud io / text / vi deo communication functions (for example tele-communication, video-communication, and / or text transmission (Short Message Service (SMS) / Multimedia Message Service (MMS)Zemailing) functions), interactive / non-interactive viewing functions (for example web-browsing, navigation, TV / program viewing functions), music recording / playing functions (for example Moving Picture Experts Group-1 Audio Layer 3 (MP3) or other format and / or (frequency modulation / amplitude modulation) radio broadcast recording / playing), downloading / sending of data functions, image capture function (for example using a (for example in-built) digital camera), and gaming functions, or any combination thereof.
[0455]
[0290] In some examples (such as wherein the apparatus is provided within a UE 110), the apparatus 10 comprises:
[0456] at least one processor 12; and
[0457] at least one memory 13 storing instructions that, when executed by the at least one processor 12, cause the apparatus at least to perform the following:
[0458] a. receiving, from a network entity, information indicative of at least one set of one or more layers based at least in part on which at least one Channel State Information, CSI, parameter is to be calculated;
[0459] b. calculating the at least one CSI parameter based at least in part on the at least one set of at least one or more layers; and
[0460] c. transmitting, to the network entity, information indicative of the at least one CSI parameter.
[0461]
[0291] The above described examples find application as enabling components of: telecommunication systems; tracking systems, automotive systems; electronic systems including consumer electronic products; distributed computing systems; media systems for generating or rendering media content including audio, visual and audio visual content and mixed, mediated, virtual and / or augmented reality; personal systems including personal health systems or personal fitness systems; navigation systems; user interfaces also known as human machine interfaces; networks including cellular, non-cellular, and optical networks; ad-hoc networks; the internet; the internet of things (IOT); Vehicle-to-everything (V2X), virtualized networks; and related software and services.
[0462]
[0292] The apparatus can be provided in an electronic device, for example, a mobile terminal, according to an example of the present disclosure. It should be understood, however, that a mobile terminal is merelyillustrative of an electronic device that would benefit from examples of implementations of the present disclosure and, therefore, should not be taken to limit the scope of the present disclosure to the same. While in certain implementation examples, the apparatus can be provided in a mobile terminal, other types of electronic devices, such as, but not limited to: mobile communication devices, hand portable electronic devices, wearable computing devices, portable digital assistants (PDAs), pagers, mobile computers, desktop computers, televisions, gaming devices, laptop computers, cameras, video recorders, GPS devices and other types of electronic systems, can readily employ examples of the present disclosure. Furthermore, devices can readily employ examples of the present disclosure regardless of their intent to provide mobility.
[0463]
[0293] FIG. 11, illustrates instructions, program or code 14 which may be conveyed via a delivery mechanism 20. The delivery mechanism 20 can be any suitable delivery mechanism, for example, a machine readable medium, a computer-readable medium, a non-transitory computer-readable storage medium, a computer program product, a memory device, a solid-state memory, a record medium such as a Compact Disc Read-Only Memory (CD-ROM) or a Digital Versatile Disc (DVD) or an article of manufacture that comprises or tangibly embodies the instructions, program or code 14. The delivery mechanism can be a signal configured to reliably transfer the computer program. An apparatus can receive, propagate or transmit the computer program as a computer data signal.
[0464]
[0294] In certain examples of the present disclosure, there is provided a computer program comprising instructions, which when executed by an apparatus (e.g. UE 110), cause the apparatus to perform at least the following or for causing performing of at least the following:
[0465] a. receiving, from a network entity, information indicative of at least one set of one or more layers based at least in part on which at least one Channel State Information, CSI, parameter is to be calculated; b. calculating the at least one CSI parameter based at least in part on the at least one set of at least one or more layers; and
[0466] c. transmitting, to the network entity, information indicative of the at least one CSI parameter.
[0467]
[0295] References to ‘instructions’ ‘computer program’, ‘computer-readable storage medium’, ‘computer program product’, ‘tangibly embodied computer program’ etc. or a ‘controller’, ‘computer’, ‘processor’ etc. should be understood to encompass not only computers having different architectures such as single / multiprocessor architectures and sequential (Von Neumann) / parallel architectures but also specialized circuits such as field-programmable gate arrays (FPGA), application specific circuits (ASIC), signal processing devices and other processing circuitry including quantum processing circuitry. References to computer program, instructions, code etc. should be understood to encompass software for a programmable processor or firmware such as, for example, the programmable content of a hardware device whether instructions for a processor, or configuration settings for a fixed-function device, gate array or programmable logic device etc.
[0468]
[0296] As used in this application, the term ‘circuitry’ can refer to one or more or all of the following:(a) hardware-only circuitry implementations (such as implementations in analog, digital and / or quantum circuitry) and
[0469] (b) combinations of hardware circuit(s) and software, such as (as applicable):
[0470]
[0297] a combination of analog, digital and / or quantum hardware circuit(s) with software / firmware and any or all portions of hardware processor(s) (including digital and / or quantum processor(s)), with software, and memory(ies) that work together to cause an apparatus, such as a mobile device, computing device, or server, to perform various functions and any or all portions of hardware circuit(s), such as a microprocessor(s), processor(s) and / or quantum processor(s), that require software (for example firmware) for operation, but the software may not be present when it is not needed for operation.
[0471]
[0298] This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also covers, for example and if applicable to a particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in a server, a cellular network device, or other computing or network device.
[0472]
[0299] Although various examples of the present disclosure have been described in the preceding paragraphs, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as set out in the claims.
[0473]
[0300] Various, but not necessarily all, examples of the present disclosure can take the form of a method, an apparatus, or a computer program. Accordingly, various, but not necessarily all, examples can be implemented in hardware, software or a combination of hardware and software.
[0474]
[0301] Various, but not necessarily all, examples of the present disclosure are described using flowchart illustrations and schematic block diagrams. It will be understood that each block (of the flowchart illustrations and block diagrams), and combinations of blocks, can be implemented by computer program instructions of a computer program. These program instructions can be provided to one or more processor(s), processing circuitry or controller(s) such that the instructions which execute on the same create means for causing implementing the functions specified in the block or blocks, i.e. such that the method can be computer implemented. The computer program instructions can be executed by the processor(s) to cause a series of operational block / steps / actions to be performed by the processor(s) to produce a computer implemented process such that the instructions which execute on the processor(s) provide block / steps for implementing the functions specified in the block or blocks.
[0475]
[0302] Accordingly, the blocks support: combinations of means for performing the specified functions; combinations of actions for performing the specified functions; and computer program instructions / algorithm for performing the specified functions. It will also be understood that each block, and combinations of blocks,can be implemented by special purpose hardware-based systems which perform the specified functions or actions, or combinations of special purpose hardware and computer program instructions.
[0476]
[0303] Various, but not necessarily all, examples of the present disclosure provide both a method and corresponding apparatus comprising various modules, means or circuitry that provide the functionality for performing / applying the actions of the method. The modules, means or circuitry can be implemented as hardware, or can be implemented as software or firmware to be performed by a computer processor. In the case of firmware or software, examples of the present disclosure can be provided as a computer program product including a computer readable storage structure embodying computer program instructions (i.e. the software or firmware) thereon for performing by the computer processor.
[0477]
[0304] Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
[0478]
[0305] Features described in the preceding description can be used in combinations other than the combinations explicitly described.
[0479]
[0306] Although functions have been described with reference to certain features, those functions can be performable by other features whether described or not.
[0480]
[0307] Although features have been described with reference to certain examples, those features can also be present in other examples whether described or not. Accordingly, features described in relation to one example / aspect of the disclosure can include any or all of the features described in relation to another example / aspect of the disclosure, and vice versa, to the extent that they are not mutually inconsistent.
[0481]
[0308] The term ‘comprise’ is used in this document with an inclusive not an exclusive meaning. That is any reference to X comprising Y indicates that X can comprise only one Y or can comprise more than one Y. If it is intended to use ‘comprise’ with an exclusive meaning then it will be made clear in the context by referring to “comprising only one ...” or by using “consisting”.
[0482]
[0309] In this description, the wording ‘connect’ and ‘communication’ and their derivatives mean operationally connected / in communication. It should be appreciated that any number or combination of intervening components can exist (including no intervening components), i.e. so as to provide direct or indirect connection / coupling / communication. Any such intervening components can include hardware and / or software components.
[0483]
[0310] As used herein, the term "determine / determining" (and grammatical variants thereof) can include, not least: evaluating, calculating, computing, processing, deriving, measuring, investigating, identifying, looking up (for example, looking up in a table, a database or another data structure), ascertaining and the like. Also, "determining" can include receiving (for example, receiving information), retrieving / accessing (for example, retrieving / accessing data in a memory), obtaining and the like. Also, " determine / determining" can include resolving, selecting, choosing, establishing, inferring and the like.
[0311] As used herein, a description of an action should also be considered to disclose enabling, and / or causing, and / or controlling that action. For example, a description of transmitting information should also be considered to disclose enabling, and / or causing, and / or controlling transmitting information. Similarly, for example, a description of an apparatus transmitting information should also be considered to disclose at least one means or controller of the apparatus enabling, and / or causing, and / or controlling the apparatus to transmit the information.”
[0484]
[0312] The term “means” as used in the description and in the claims may refer to one or more individual elements configured to perform the corresponding recited functionality or functionalities, or it may refer to several elements that perform such functionality or functionalities. Furthermore, several functionalities recited in the claims may be performed by the same individual means or the same combination of means. For example performing such functionality or functionalities may be caused in an apparatus by a processor that executes instructions stored in a memory of the apparatus.
[0485]
[0313] References to a parameter, or value of a parameter, should be understood to refer to “data indicative of”, “data defining” or “data representative of” the relevant parameter / parameter value if not explicitly stated (unless the context demands otherwise). The data may be in any way indicative of the relevant parameter / parameter value, and may be directly or indirectly indicative thereof.
[0486]
[0314] In this description, reference has been made to various examples. The description of features or functions in relation to an example indicates that those features or functions are present in that example. The use of the term ’example’ or ‘for example’, ‘can’ or ‘may’ in the text denotes, whether explicitly stated or not, that such features or functions are present in at least the described example, whether described as an example or not, and that they can be, but are not necessarily, present in some or all other examples. Thus ‘example’, ‘for example’, ‘can’ or ‘may’ refers to a particular instance in a class of examples. A property of the instance can be a property of only that instance or a property of the class or a property of a sub-class of the class that includes some but not all of the instances in the class.
[0487]
[0315] In this description, references to “a / an / the” [feature, element, component, means ...] are used with an inclusive not an exclusive meaning and are to be interpreted as “at least one” [feature, element, component, means ...] unless explicitly stated otherwise. That is any reference to X comprising a / the Y indicates that X can comprise only one Y or can comprise more than one Y unless the context clearly indicates the contrary. If it is intended to use ‘a’ or ‘the’ with an exclusive meaning then it will be made clear in the context. In some circumstances the use of ‘at least one’ or ‘one or more’ can be used to emphasise an inclusive meaning but the absence of these terms should not be taken to infer any exclusive meaning.
[0488]
[0316] As used herein, “at least one of the following: ” and “at least one of ” and similar wording, where the list of two or more elements are joined by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.
[0317] As used herein, the terms “the at least one” and “the one or more” mean “any one of the at least one” and “any one of the one or more”, respectively.
[0489]
[0318] The presence of a feature (or combination of features) in a claim is a reference to that feature (or combination of features) itself and also to features that achieve substantially the same technical effect (equivalent features). The equivalent features include, for example, features that are variants and achieve substantially the same result in substantially the same way. The equivalent features include, for example, features that perform substantially the same function, in substantially the same way to achieve substantially the same result.
[0490]
[0319] In this description, reference has been made to various examples using adjectives or adjectival phrases to describe characteristics of the examples. Such a description of a characteristic in relation to an example indicates that the characteristic is present in some examples exactly as described and is present in other examples substantially as described.
[0491]
[0320] In the above description, the apparatus described can alternatively or in addition comprise an apparatus which in some other examples comprises a distributed system of apparatus, for example, a client / server apparatus system. In examples where an apparatus provided forms (or a method is implemented as) a distributed system, each apparatus forming a component and / or part of the system provides (or implements) one or more features which collectively implement an example of the present disclosure. In some examples, an apparatus is re-configured by an entity other than its initial manufacturer to implement an example of the present disclosure by being provided with additional software, for example by a user downloading such software, which when executed causes the apparatus to implement an example of the present disclosure (such implementation being either entirely by the apparatus or as part of a system of apparatus as mentioned hereinabove).
[0492]
[0321] The above description describes some examples of the present disclosure however those of ordinary skill in the art will be aware of possible alternative structures and method features which offer equivalent functionality to the specific examples of such structures and features described herein above and which for the sake of brevity and clarity have been omitted from the above description. Nonetheless, the above description should be read as implicitly including reference to such alternative structures and method features which provide equivalent functionality unless such alternative structures or method features are explicitly excluded in the above description of the examples of the present disclosure.
[0493]
[0322] Whilst endeavouring in the foregoing specification to draw attention to those features of examples of the present disclosure believed to be of particular importance it should be understood that the applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and / or shown in the drawings whether or not particular emphasis has been placed thereon.
[0494]
[0323] The examples of the present disclosure and the accompanying claims can be suitably combined in any manner apparent to one of ordinary skill in the art. Separate references to an “example”, “in someexamples” and / or the like in the description do not necessarily refer to the same example and are also not mutually exclusive unless so stated and / or except as will be readily apparent to those skilled in the art from the description. For instance, a feature, structure, process, block, step, action, or the like described in one example may also be included in other examples, but is not necessarily included.
[0495]
[0324] Each and every claim is incorporated as further disclosure into the specification and the claims are embodiment(s) of the present disclosure. Further, while the claims herein are provided as comprising specific dependencies, it is contemplated that any claims can depend from any other claims and that to the extent that any alternative embodiments can result from combining, integrating, and / or omitting features of the various claims and / or changing dependencies of claims, any such alternative embodiments and their equivalents are also within the scope of the disclosure.
Claims
1. CLAIMS1. An apparatus comprising:at least one processor; andat least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to perform the following:receiving, from a network entity, information indicative of at least one set of one or more layers based at least in part on which at least one Channel State Information, CSI, parameter is to be calculated; calculating the at least one CSI parameter based at least in part on the at least one set of at least one or more layers; andtransmitting, to the network entity, information indicative of the at least one CSI parameter.
2. The apparatus of claim 1, wherein the at least one memory further stores instructions that, when executed by the at least one processor, cause the apparatus to perform at least one of the following:receiving, from the network entity, information for configuring the apparatus to report the at least one CSI parameter based at least in part on the at least one set of at least one or more layers indicated through the information received from the network entity.
3. The apparatus of any previous claim, wherein the at least one memory further stores instructions that, when executed by the at least one processor, cause the apparatus to perform at least one of the following:receiving, from the network entity, information for configuring the apparatus to report at least one first CSI parameter, wherein the at least one first CSI parameter is calculated based at least in part on at least one first set of at least one or more layers.
4. The apparatus of claim 3, wherein the at least one first set of at least one or more layers is determined by the apparatus based at least in part on at least one of the following:at least one channel measurement;at least one interference measurement;at least one measurement of at least one reference signal, RS; orat least one measurement of at least one Channel State Information, CSI, RS.
5. The apparatus of any previous claim, wherein the at least one memory further stores instructions that, when executed by the at least one processor, cause the apparatus to perform at least one of the following:determining the at least one set of one or more layers based at least in part on the information indicative of the at least one set of one or more layers;determining the at least one set of one or more layers based at least in part on at least one configured rule;determining the at least one set of one or more layers based on at least one pre-defined specification; ordetermining the at least one set of one or more layers based on determining that at least one condition has been met.
6. The apparatus of any of previous claim when dependent upon claim 3, wherein the at least one memory further stores instructions that, when executed by the at least one processor, cause the apparatus to perform at least one of the following:determining the at least one set of one or more layers based at least in part on the at least one first set of at least one or more layers.
7. The apparatus of any previous claim when dependent upon claim 3, wherein the at least one memory further stores instructions that, when executed by the at least one processor, cause the apparatus to perform at least one of the following:receiving, from the network entity, information for enabling the apparatus to determine the at least one set of one or more layers based at least in part on the at least one first set of at least one or more layers.
8. The apparatus of any of claims 5 to 7, wherein determining the at least one set of one or more layers comprises at least one of the following:receiving the at least one set of one or more layers from the network entity;receiving information indicative of one or more identifiers of the one or more layers from the network entity;receiving information indicative of a rank indicator value.
9. The apparatus of any of claims 3 to 8, wherein the at least one set of at least one or more layers differs at least in part to the at least one first set of at least one or more layers.
10. The apparatus of any previous claim when dependent upon claims 2 and 3, wherein the information for configuring the apparatus to report the at least one CSI parameter, or the information indicative of the at least one set of one or more layers, is at least one of the following:comprised in the information for configuring the apparatus to report the at least one first CSI parameter;associated with the information for configuring the apparatus to report the at least one first CSI parameter; orbased at least in part on the information for configuring the apparatus to report the at least one first CSI parameter.
11. The apparatus of any previous claim when dependent upon claims 2, wherein receiving the information for configuring the apparatus to report the at least one CSI parameter, or receiving the information indicative of the at least one set of one or more layers, comprises at least one of the following:determining a CSI trigger state, wherein the CSI trigger state is associated withinformation for configuring the apparatus to transmit the at least one CSI parameter, or the information indicative of the at least one set of one or more layers; or determining a CSI trigger state, wherein the CSI trigger state is associated with at least a part of:information for configuring the apparatus to transmit the at least one CSI parameter, or the information indicative of the at least one set of one or more layers.
12. The apparatus of any previous claim, wherein transmitting, to the network entity, the information indicative of the at least one CSI parameter is based at least in part on determining whether at least one condition has been met.
13. The apparatus of any previous claim when dependent upon claim 12, wherein the at least one condition is based at least in part on at least one of the following:the at least one set of one or more layers;the at least one first set of at least one or more layers;the at least one set of one or more layers differing at least in part from the at least one first set of at least one or more layers;the at least one CSI parameter;the at least one first CSI parameter; orthe at least one CSI parameter differing at least in part from the at least one first CSI parameter by a threshold amount.
14. The apparatus of any previous claim, wherein at least one of:the information indicative of the at least one CSI parameter is transmitted in a CSI report;at least a part of the information indicative of the at least one CSI parameter is transmitted in a CSI report;the information indicative of the at least one CSI parameter is transmitted in a first part of a CSI report; orthe information indicative of the at least one CSI parameter is transmitted in a second part of a CSI report.
15. The apparatus of claim 14 when dependent on claim 3, wherein at least one of:the information indicative of the at least one first CSI parameter is transmitted in a first part of the CSI report;the information indicative of the at least one first CSI parameter is transmitted in a second part of the CSI report;the information indicative of the at least one first CSI parameter is transmitted in a first part of a CSI report which is different, at least in part, to the CSI report in which the information indicative of the at least one CSI parameter is transmitted; orthe information indicative of the at least one first CSI parameter is transmitted in a second part of a CSI report which is different, at least in part, to the CSI report in which the information indicative of the at least one CSI parameter is transmitted.
16. The apparatus of any previous claim, wherein the at least one memory further stores instructions that, when executed by the at least one processor, cause the apparatus to perform at least one of the following:receiving, from the network entity, information indicative of at least one set of resources for at least one RS, and wherein the at least one CSI parameter is calculated based at least in part on at least one measurement of the at least one RS; orreceiving, from the network entity, information indicative of at least one set of resources for at least one channel, and wherein the at least one CSI parameter is calculated based at least in part on at least one measurement of the at least one channel.
17. The apparatus of any of previous claim when dependent upon claim 3, wherein the at least one memory further stores instructions that, when executed by the at least one processor, cause the apparatus to perform at least one of the following:receiving, from the network entity, information indicative of one or more first resources for one or more first RSs; and wherein the at least one first CSI parameter is calculated based at least in part on one or more measurements of the one or more first RSs.
18. The apparatus of claim 17 when dependent upon claim 16, wherein, at least one of:the information indicative of at least one set of resources for at least one RS is comprised in or associated with information indicative of one or more first resources for one or more first RSs; the at least one set of resources is based on the one or more first resources;the at least one set of resources is the same as the one or more first resources;the at least one set of resources is a subset of the one or more first resources; orthe at least one set of resources is different at least in part to the one or more first resources.
19. The apparatus of any previous claim when dependent upon claim 3, wherein the at least one memory further stores instructions that, when executed by the at least one processor, cause the apparatus to perform:transmitting, to the network entity, information indicative of the at least one first CSI parameter, wherein the information indicative of the at least one first CSI parameter and the information indicative of the at least one CSI parameter are comprised in:a same uplink transmission or resource; ora separate uplink transmission or resource.
20. The apparatus of any previous claim, wherein the information indicative of the at least one CSI parameter comprises at least one of the following:at least one Channel Quality Indicator, CQI;at least one Precoding Matrix Indicator, PMI;a Rank Indicator, Rl;at least one Layer Indicator, LI;at least one interference information;at least one Interference-plus-Noise information;at least one power information;at least one Reference Signal Received Power, RSRPat least one Reference Signal Received Quality, RSRQ; orat least one Signal-to-lnterference-plus-Noise Ratio, SINR.
21. The apparatus any previous claim when dependent upon claim 3, wherein the information indicative of the at least one CSI parameter comprises at least one of the following:at least one value of the at least one CSI parameter;at least one value based at least in part on:at least one value of the at least one CSI parameter, andat least one value of the at least one first CSI parameter;at least one difference between:at least one value of the at least one CSI parameter, andat least one value of the at least one first CSI parameter; orat least one value based at least in part on:at least one function of at least one value of the at least one CSI parameter, and at least one function of at least one value of the at least one first CSI parameter.
22. The apparatus of any previous claim, wherein the at least one set of one or more layers comprises or corresponds to at least one of the following:at least one Rank Indicator, Rl;at least one Multiple Input Multiple Output, MIMO, layer;at least one transmission layer; orat least one spatial element.
23. A User Equipment, UE, comprising the apparatus of any previous claim.
24. A method comprising:receiving, from a network entity, information indicative of at least one set of one or more layers based at least in part on which at least one Channel State Information, CSI, parameter is to be calculated;calculating the at least one CSI parameter based at least in part on the at least one set of at least one or more layers; andtransmitting, to the network entity, information indicative of the at least one CSI parameter.
25. A non-transitory computer readable medium comprising instructions, when executed by an apparatus, causes the apparatus to perform at least the method of claim 24.