New Radio (NR) Multiple Input Multiple Output (MIMO) Channel State Information (CSI) Design for Small Bandwidth Part (BWP)

Abstract

To provide apparatuses and methods for implementing capability signaling design for 3GPP Rel-15 and / or Rel-16 MIMO enhancement.SOLUTION: For example, systems and methods are provided implementing designs for New Radio (NR) MIMO channel state information (CSI) for a small bandwidth part (BWP) and / or a small number of subbands. For example, some aspects relate to user equipment (UE) including a transceiver configured to communicate with a base station and a processor communicatively coupled to the transceiver. The processor receives, from the base station, a CSI reporting configuration message. The processor determines, using the CSI reporting configuration message, that some physical resource blocks (PRBs) of a BWP associated with the CSI reporting configuration message is less than a threshold number. The processor also generates and transmits a CSI report for the BWP.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] For example, some aspects of the present disclosure relate to designing for Channel State Information (CSI) for a small bandwidth part (BWP) and / or a small number of sub-bands. [Background technology]

[0002] User equipment (UE) communicating with a base station (e.g., an Evolved Node B (eNB)) over a communication link may measure channel characteristics of the communication link. For example, the UE may measure how a signal propagates in a downlink channel from the base station to the UE. The UE may generate a channel state information (CSI) report based on the measured channel characteristics. The UE may transmit the CSI report to the base station. The base station may use the received CSI report to adapt its transmissions based on the channel characteristics reported by the UE. Summary of the Invention

[0003] Some aspects of the present disclosure relate to apparatus and methods for implementing capability signaling designs for 3rd Generation Partnership Project (3GPP) Release 15 (Rel-15) and / or Release 16 (Rel-16) Multiple-Input Multiple-Output (MIMO) enhancements. For example, systems and methods are provided that implement designs for New Radio (NR) MIMO Channel State Information (CSI) for small bandwidth portions (BWPs) and / or a small number of subbands.

[0004] Some aspects of the present disclosure relate to a user equipment (UE). The UE includes a transceiver configured to communicate with a base station over a wireless network and a processor communicatively coupled to the transceiver. The processor receives a channel state information (CSI) report configuration message from the base station using the transceiver. The processor further determines, using the CSI report configuration message, that a number of physical resource blocks (PRBs) of a bandwidth portion (BWP) associated with the CSI report configuration message are less than a threshold number. The processor also generates a CSI report for the BWP and transmits the CSI report to the base station using the transceiver.

[0005] In some examples, the processor is further configured to send, using the transceiver, a message to the base station indicating that the UE is configured to generate a CSI report for BWP. In some examples, the message further indicates one or more codebook types, for which the UE is configured to generate a CSI report for BWP. In some examples, the processor is configured to generate a CSI report for at least one of a 3rd Generation Partnership Project (3GPP) Release 15 (Rel-15) Type-I single-panel CSI codebook, a Rel-15 Type-I multi-panel CSI codebook, a Rel-15 Type-II CSI codebook, a Rel-15 Type-II port-selection CSI codebook, a Release 16 (Rel-16) Type-II CSI codebook, or a Rel-16 Type-II port-selection CSI codebook.

[0006] In some examples, a CSI report is associated with one subband, and the CSI report includes a wideband Channel Quality Indicator (CQI) and a wideband Precoding Matrix Indicator (PMI). In these examples, the size of the subband is equal to the size of the BWP.

[0007] In some examples, the CSI report is associated with one subband for a precoding matrix indicator (PMI). Alternatively, the CSI report is associated with two subbands for a PMI. In this example, in response to the number of PRBs of the BWP being an even number, the number of PRBs in each of the two subbands is half the number of PRBs of the BWP. However, in response to the number of PRBs of the BWP being an odd number, one of the two subbands has one less PRB than the other of the two subbands.

[0008] In some examples, in response to the csi-ReportingBand of the CSI report configuration message being not configured or having a bitmap with a value of 0 for each of the bits of the bitmap, the processor is configured to determine that an error has occurred or to generate a CSI report including a wideband channel quality indicator (CQI) and a wideband precoding matrix indicator (PMI).

[0009] Some aspects of the present disclosure relate to a method. The method includes receiving a channel state information (CSI) report configuration message from a base station by a user equipment (UE). The method further includes determining, using the CSI report configuration message, that a number of physical resource blocks (PRBs) of a bandwidth portion (BWP) associated with the CSI report configuration message are less than a threshold number. The method may also include generating a CSI report for the BWP for at least one of a 3rd Generation Partnership Project (3GPP) Release 15 (Rel-15) Type-I single-panel CSI codebook, a Rel-15 Type-I multi-panel CSI codebook, a Rel-15 Type-II CSI codebook, a Rel-15 Type-II port-selection CSI codebook, a Release 16 (Rel-16) Type-II CSI codebook, or a Rel-16 Type-II port-selection CSI codebook. The method also includes transmitting the CSI report to the base station.

[0010] Some aspects of the present disclosure relate to a non-transitory computer-readable medium storing instructions. When the instructions are executed by a processor of a user equipment (UE), the instructions cause the processor to perform operations including receiving a channel state information (CSI) report configuration message by the UE from a base station. The operations further include determining, using the CSI report configuration message, that a number of physical resource blocks (PRBs) of a bandwidth portion (BWP) associated with the CSI report configuration message are less than a threshold number. The operations further include generating a CSI report for the BWP for at least one of a 3rd Generation Partnership Project (3GPP) Release 15 (Rel-15) Type-I single-panel CSI codebook, a Rel-15 Type-I multi-panel CSI codebook, a Rel-15 Type-II CSI codebook, a Rel-15 Type-II port-selection CSI codebook, a Release 16 (Rel-16) Type-II CSI codebook, or a Rel-16 Type-II port-selection CSI codebook. The operations also include transmitting the CSI report to the base station.

[0011] Some aspects of the present disclosure relate to a base station. The base station includes a transceiver configured to communicate with user equipment (UE) over a wireless network and a processor communicatively coupled to the transceiver. The processor receives, using the transceiver, a message from the UE indicating that the UE is configured to generate channel state information (CSI) for a bandwidth portion (BWP) having less than a threshold number of physical resource blocks (PRBs). The processor transmits, using the transceiver, a CSI report configuration message to the UE, the CSI report including the BWP having less than the threshold number of PRBs. The processor can also receive, using the transceiver, a CSI report for the BWP from the UE and adapt data transmission(s) to the UE based on the CSI report.

[0012] Some aspects of the present disclosure relate to a user equipment (UE). The UE includes a transceiver configured to communicate with a base station over a wireless network and a processor communicatively coupled to the transceiver. The processor receives a channel state information (CSI) report configuration message from the base station using the transceiver. The processor determines a parameter using the CSI report configuration message and compares the determined parameter with a threshold. In response to the parameter being equal to or greater than the threshold, the processor generates a CSI report and transmits the CSI report to the base station using the transceiver.

[0013] In some examples, the parameters include a maximum number of non-zero coefficients, and the threshold has a value of 2 in response to a Rank Indicator (RI) having a value of 1 or 2, a value of 3 in response to RI having a value of 3, and a value of 4 in response to RI having a value of 4.

[0014] In some examples, the CSI report configuration message includes reporting band information, and the parameter includes a number of CSI subbands determined from the reporting band information. For example, the reporting band information includes a bitmap, and the processor is configured to determine the number of CSI subbands based on a number of bits having a value of 1 in the bitmap. In some examples, the threshold includes a minimum number of CSI subbands and has a value of 5 in response to a rank indicator (RI) having a value of 1 or 2, a value of 9 in response to the RI having a value of 3, and a value of 13 in response to the RI having a value of 4. In some examples, the threshold includes a minimum number of CSI subbands and has a value of 5 in response to the rank indicator (RI) having a value of 3 or 4.

[0015] In some examples, the processor is configured to generate a CSI report for a Release 16 (Rel-16) Type II codebook.

[0016] In some examples, the processor is configured to transmit, using the transceiver, a message to the base station including a threshold used by the UE to determine whether to generate a CSI report.

[0017] Some aspects of the present disclosure relate to a method. The method includes receiving a channel state information (CSI) report configuration message by a user equipment (UE) from a base station. The method also includes determining a parameter using the CSI report configuration message and comparing the determined parameter to a threshold. The method further includes generating a CSI report in response to the parameter being greater than or equal to the threshold, where the CSI report is generated for a Release 16 (Rel-16) Type II codebook. The method also includes transmitting the CSI report to the base station.

[0018] Some aspects of the present disclosure relate to a non-transitory computer-readable medium storing instructions. When the instructions are executed by a processor of a user equipment (UE), the instructions cause the processor to perform operations including receiving, by the UE, a channel state information (CSI) report configuration message from a base station. The operations also include determining a parameter using the CSI report configuration and comparing the determined parameter to a threshold. The operations further include generating a CSI report in response to the parameter being greater than or equal to the threshold, the CSI report being generated for a Release 16 (Rel-16) Type II codebook. The operations also include transmitting the CSI report to the base station.

[0019] Some aspects of the present disclosure relate to a base station. The base station includes a transceiver configured to communicate with a user equipment (UE) over a wireless network and a processor communicatively coupled to the transceiver. The processor receives a message from the user equipment (UE) using the transceiver, the message including a threshold used by the UE to determine whether to generate a CSI report. The processor transmits a CSI report configuration message to the UE using the transceiver. The processor can also receive a CSI report for BWP from the UE using the transceiver and adapt data transmission(s) to the UE based on the CSI report.

[0020] This Summary of the Invention is provided merely for the purpose of illustrating some aspects to provide an understanding of the subject matter described herein. Accordingly, the above features are merely examples and should not be construed as narrowing the scope or spirit of the subject matter in this disclosure. Other features, aspects, and advantages of the present disclosure will become apparent from the following Detailed Description, Figures, and Claims.

[0021] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate the present disclosure and, together with the description, further serve to explain the principles of the present disclosure and to enable one skilled in the art(s) to make and use the present disclosure. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 illustrates an example system that implements a design for New Radio (NR) multiple-input multiple-output (MIMO) channel state information (CSI) for a small bandwidth portion (BWP) and / or a small number of subbands in accordance with certain aspects of the present disclosure. [Figure 2] FIG. 1 is a block diagram of an example system of an electronic device that implements a design for New Radio (NR) multiple-input multiple-output (MIMO) channel state information (CSI) for a small bandwidth portion (BWP) and / or a small number of subbands in accordance with certain aspects of the present disclosure. [Figure 3] FIG. 1 illustrates an example method for a system (e.g., a user equipment (UE)) that supports mechanisms for implementing multiple-input multiple-output (MIMO) channel state information (CSI) for a small bandwidth portion (BWP), in accordance with certain aspects of the present disclosure. [Figure 4] FIG. 1 illustrates an example method for a system (e.g., a base station) that supports a mechanism for implementing multiple-input multiple-output (MIMO) channel state information (CSI) for a small bandwidth portion (BWP), in accordance with certain aspects of the present disclosure. [Figure 5] FIG. 1 illustrates an example method for a system (e.g., a user equipment (UE)) that supports mechanisms for implementing multiple-input multiple-output (MIMO) channel state information (CSI) for a small number of subbands, in accordance with certain aspects of the present disclosure. [Figure 6] FIG. 1 illustrates an example method for a system (e.g., a base station) that supports mechanisms for implementing multiple-input multiple-output (MIMO) channel state information (CSI) for a small number of subbands, in accordance with certain aspects of the present disclosure. [Figure 7] FIG. 1 illustrates an exemplary computer system for implementing some aspects or portion(s) of some aspects.

[0023] The present disclosure is described with reference to the accompanying drawings, in which like reference numbers generally indicate identical or functionally similar elements, and the most significant digit(s) of a reference number generally identifies the drawing in which the reference number first appears. DETAILED DESCRIPTION OF THE INVENTION

[0024] Some aspects of the present disclosure include apparatuses and methods for implementing capability signaling designs for Rel-15 and / or Rel-16 MIMO enhancements. For example, systems and methods are provided for CSI reporting when the number of physical resource blocks (PRBs) in a BWP is less than a threshold number (e.g., 24 PRBs). Additionally, systems and methods are provided for CSI reporting when the number of subbands is small (e.g., for Rel-16 Type II CSI).

[0025] According to some aspects, a UE operating in accordance with Release 15 (Rel-15) and / or Release 16 (Rel-16) New Radio (NR) of 5th Generation (5G) radio technology for digital cellular networks as defined by the 3rd Generation Partnership Project (3GPP) can report channel state information (CSI) to a network with which the UE communicates. For example, the UE can report the CSI to a base station (e.g., a Next Generation Node B (gNB)) with which the UE communicates. According to some aspects, the CSI report may include, but is not limited to, a Channel Quality Indicator (CQI), a Precoding Matrix Indicator (PMI), a CSI-RS Resource Indicator (CRI), a SS / PBCH (Synchronization Signal (SS) / Physical Broadcast Channel (PBCH) Block Resource Indicator (SS BRI), a Layer Indicator (LI), a Rank Indicator (RI), and / or an L1-Reference Signal Received Power (L1-RSRP) associated with at least a communication link over which the network communicates with the UE.

[0026] The resources (e.g., time and / or frequency resources) used by the UE to report CSI are controlled by a base station (e.g., a gNB). According to some examples, the resources for CSI reporting, the CSI reporting configuration, and / or the CSI codebook type may be configured by the base station during a Radio Resource Control (RRC) connection setup process.

[0027] According to some aspects, before connecting to a base station, a UE can search for a cell to attach to. After completing the search, the UE can perform an RRC connection setup process. In one example, the UE can send an attach request to a base station and / or a mobility management entity (MME) associated with the base station. In some examples, the attach request can include an identifier of the UE. In some aspects, if the MME accepts the attach request, the MME can send a setup request to, for example, a base station. In some examples, after receiving the setup request, and if the base station does not know the capabilities of the UE, the base station can send a request to the UE to request the capabilities of the UE. According to some aspects, the UE can send the capabilities of the UE to the base station. In response, the base station can send an RRC connection reconfiguration message back to the UE. The UE can then start data communication using the base station.

[0028] According to some aspects, RRC setup (as discussed above as one exemplary connection setup) can configure CSI reporting in the UE. For example, an RRC connection reconfiguration message (or any other RRC message) can include information and / or instructions for configuring CSI reporting in the UE. Rel-15 and Rel-16 can include different CSI reporting configurations with associated CSI codebook types for Rel-15 and Rel-16. As a non-limiting example, New Radio (NR) Rel-15 / 16 multiple-input multiple-output (MIMO) can support six types of CSI reporting configurations with associated CSI codebooks for Rel-15 and Rel-16. These CSI codebook types can include codebook types for Rel-15 Type I single panel, Rel-15 Type I multi-panel, Rel-15 Type II CSI, Rel-15 Type II CSI with port selection, Rel-16 Type II CSI, and Rel-16 Type II CSI with port selection.

[0029] According to some aspects, a base station may transmit a CSI report configuration message (e.g., an RRC message) to configure a CSI report in a UE. The CSI report configuration message may be associated with a single downlink bandwidth portion (BWP). The CSI report configuration message may indicate the BWP to the UE for channel measurements, for example, by including an identifier (ID) associated with the BWP (e.g., a BWP ID). The CSI report configuration message may also include a codebook configuration (and / or information associated with the codebook configuration) for the UE. The CSI report configuration message may also include one or more parameters indicating a scheduling method for the CSI report (e.g., whether the CSI report is periodic, aperiodic, etc.).

[0030] The CSI report configuration message may also include one or more parameters that indicate the reporting granularity in the frequency domain. For example, the NR Rel-15 / 16 MIMO CSI report may have three configurations: a.cqi-FormatIndicator: wideband or subband channel quality indicator (CQI); b. pmi-FormatIndicator: wideband or subband precoding matrix indicator (PMI), c.csi-ReportingBand: Sub-band configuration It can be configured based on the following.

[0031] The CSI reporting configuration message may include a cqi-FormatIndicator, a pmi-FormatIndicator, and / or a csi-ReportingBand.

[0032] As discussed in more detail below, the subband configuration may indicate to the UE the number of subbands in the BWP. In some examples, the subband configuration may include a bitmap. This bitmap may indicate to the UE the number of subbands in the BWP and may also indicate for which subband(s) the UE needs to report CSI. In one example, a value of "0" in the bitmap for a subband may indicate that the UE does not need to report CSI for that subband. A value of "1" in the bitmap for another subband may indicate that the UE needs to report CSI for that subband.

[0033] The base station can request the UE to report a wideband channel quality indicator (CQI) or a sub-band CQI, for example, using a CSI report configuration message and as indicated by, for example, a cqi-FormatIndicator. In the case of wideband CQI, the UE can report one value for CQI for the entire BWP. In the case of sub-band CQI, the UE can report one or more values ​​of CQI based on a bitmap of the sub-band configuration.

[0034] Similarly, the base station can request the UE to report a wideband precoding matrix indicator (PMI), for example, using a CSI report configuration message and as indicated by, for example, pmi-FormatIndicator. In the case of wideband PMI, the UE can report one value for PMI for the entire BWP. In the case of subband PMI, the UE can report one or more values ​​of PMI based on a bitmap of the subband configuration.

[0035] Although several examples of the content of the CSI report configuration message are provided above, aspects of the present disclosure are not limited to these examples, and the CSI report configuration message may include fewer, more, or other parameters, instructions, and / or information.

[0036] According to some aspects, the sub-band configuration (csi-ReportingBand) may be a function of the size of the BWP. Table 1 provides an example sub-band configuration. [Table 1]

[0037] In one example, as shown in Table 1, if the BWP has 24 physical resource blocks (PRBs), the subband size may be 4 or 8 PRBs. For example, if the subband size is 4 PRBs, the BWP has 6 subbands. In this example, the subband configuration in the CSI report configuration message may include a bitmap having 6 bits, each of which is associated with one subband. Depending on the value of the bit (e.g., "1" or "0"), the UE may report (or not report) CSI for that bit.

[0038] However, as shown in Table 1, for a BWP having a size of less than 24 PRBs (in other words, the number of PRBs for this BWP is less than 24), no subbands are defined for CSI reporting.

[0039] In addition, the base station can configure the UE to report any subset of subbands within all subbands, including the special cases of one subband or two subbands. However, the number of subbands may not be sufficient for compression, which, if used, may result in reports that are inaccurate and / or not useful to the base station. In other words, in some examples in Rel-15, a large number of subbands may be used for CSI reporting. A large number of subbands may result in large overhead. In Rel-16, compression mechanism(s) are used to reduce the overhead. However, if the number of subbands is small, compression may produce undesirable results (e.g., CSI reports that are not valid, accurate, and / or not useful to the base station).

[0040] According to some aspects of the present disclosure, systems and methods are contemplated for providing capability signaling designs for Rel-15 and / or Rel-16 MIMO enhancements. For example, as discussed below, systems and methods are provided for CSI reporting when some PRBs of a BWP are less than a threshold number (e.g., 24 PRBs). Additionally or alternatively, systems and methods are provided for CSI reporting when the number of subbands is small (e.g., for Rel-16 Type II CSI).

[0041] FIG. 1 illustrates an example system 100 implementing a design for New Radio (NR) multiple-input multiple-output (MIMO) channel state information (CSI) for a small bandwidth portion (BWP) and / or a small number of subbands in accordance with some aspects of the present disclosure. The example system 100 is provided for illustrative purposes only and does not limit aspects of the disclosure. The system 100 may include, but is not limited to, a network node (e.g., a base station such as an eNB or gNB) 101 and an electronic device (e.g., a UE) 105. The electronic device 105 (hereinafter referred to as the UE 105) may include an electronic device configured to operate based on a variety of wireless communication techniques. These techniques may include, but are not limited to, techniques based on the 3rd Generation Partnership Project (3GPP) standards. For example, the UE 105 may include an electronic device configured to operate using Release 15 (Rel-15), Release 16 (Rel-16), or later. The UEs 105 may include, but are not limited to, wireless communication devices, smartphones, laptops, desktops, tablets, personal assistants, monitors, televisions, wearable devices, Internet of Things (IoT), and vehicular communication devices. The network nodes 101 (referred to herein as base stations) may include nodes configured to operate based on a wide variety of wireless communication techniques, including, but not limited to, techniques based on 3GPP standards. For example, the base stations 103 may include nodes configured to operate using Rel-15, Rel-16, or later.

[0042] The UE 105 may be connected to and in communication with the base station 101 using one or more communication links 107. According to some aspects, the UE 105 may be configured to measure how signals propagate in a downlink channel in the communication link 107 from the base station 101 to the UE 105. The UE 105 may generate a channel state information (CSI) report based on the measured channel characteristics. The UE 105 may transmit the CSI report to the base station 101. The base station 101 may use the received CSI report to adapt its transmissions based on the channel characteristics reported by the UE 105. According to some aspects, the UE 105 and the base station 101 are configured to implement a mechanism for CSI reporting when the BWP is small (e.g., but not limited to, a BWP with less than a threshold number of PRBs (e.g., 24)). Additionally or alternatively, the UE 105 and the base station 101 are configured to implement a mechanism for CSI reporting when the number of subbands is small (eg, for Rel-16 Type II CSI).

[0043] According to some aspects, before connecting to the base station 101, the UE 105 may search for a cell to attach to. After completing the search, the UE 105 may perform a radio resource control (RRC) connection setup process. In one example, the UE 105 may send an attach request to the base station 101 and / or a mobility management entity (MME) (not shown) associated with the base station 101. In some examples, the attach request may include an identifier of the UE 105. In some aspects, if the MME accepts the attach request, the MME may send a setup request to, for example, the base station 101. In some examples, after receiving the setup request, and if the base station 101 does not know the capabilities of the UE 105, the base station 101 may send a request to the UE 105 to request the capabilities of the UE 105. According to some aspects, the UE 105 may send the capabilities of the UE 105 to the base station 101. In response, the base station 101 may send an RRC connection reconfiguration message back to the UE 105. The UE 105 can then begin data communication using the base station 101. In addition, the UE 105 can transmit a CSI report(s) to the base station.

[0044] According to some aspects, the UE 105 is configured to report CSI for small BWPs (e.g., BWPs with less than a threshold number of PRBs). In some examples, the threshold number of PRBs includes 24 PRBs. However, other numbers of PRBs may be used as the threshold number.

[0045] In some examples, the UE 105 may report CSI for a small BWP for Rel-15 Type I CSI. Rel-15 Type I can include Rel-15 Type I single panel and Rel-15 Type I multi-panel, or Rel-15 Type I single panel only. In this example, the UE 105 does not report CSI for a small BWP for Rel-15 Type II or Rel-16 Type CSI.

[0046] Alternatively, the UE 105 can report CSI for the small BWP for Rel-15 Type I CSI and Rel-15 Type II CSI. Rel-15 Type I can include Rel-15 Type I single panel and Rel-15 Type I multi-panel, or Rel-15 Type I single panel only. Rel-15 Type II can include Rel-15 Type II CSI and Rel-15 Type II CSI with port selection. In this example, the UE 105 does not report CSI for the small BWP for Rel-16 Type CSI.

[0047] Alternatively, the UE 105 can report CSI for the small BWP for Rel-15 Type I CSI, Rel-15 Type II CSI, and Rel-16 Type II CSI. Rel-15 Type I can include Rel-15 Type I single panel and Rel-15 Type I multi-panel, or Rel-15 Type I single panel only. Rel-15 Type II can include Rel-15 Type II CSI and Rel-15 Type II CSI with port selection. Rel-16 Type II CSI can also include Rel-16 Type II CSI with port selection.

[0048] According to some aspects, the UE 105 may be configured to indicate its capabilities to the base station 101. For example, during the example initial communication (or any other initial access) discussed above, the UE 105 may communicate its capabilities to the base station 101. The UE 105 may communicate to the base station 101 whether the UE 105 can support CSI reporting for small BWPs (e.g., BWPs with less than a threshold number of PRBs (e.g., 24 PRBs)) for the following codebook types: Rel-15 Type I CSI, Rel-15 Type II CSI, and / or Rel-16 Type I CSI. In other words, the UE 105 may indicate to the base station 101 whether the UE 105 supports CSI reporting for small BWPs. In addition, the UE 105 may indicate to the base station 101 for which codebook types the UE 105 supports CSI reporting for small BWPs. According to some examples, if the UE 105 does not support a certain codebook type for a small BWP, the UE 105 is not expected to be configured with CSI reports for the corresponding codebook type when the small BWP is used.

[0049] According to some aspects, if the UE 105 supports CSI reporting for small BWPs for a certain codebook type, the network may define the number of CSI subbands for small BWPs for that codebook type. In one example implementation, for Rel-15 Type-I CSI and for Rel-15 Type-II CSI, the number of CSI subbands for small BWPs (e.g., BWPs with less than a threshold number of PRBs (e.g., 24 PRBs)) is 1. In this example, the UE 105 is expected to report wideband CQI and / or wideband PMI.

[0050] In another example, for Rel-16 Type II CSI, the UE 105 reports a wideband CQI. For the PMI, the UE 105 may have at least two options for reporting the PMI. In one example, the number of PMI subbands may be R, where R is 1 or 2, subject to the capabilities of the UE 105. In this example, the number of CSI subbands is also R, where R is 1 or 2, subject to the capabilities of the UE 105. In some examples, the value of R may be configured by the network (e.g., the base station 101 and / or a network associated with the base station 101). In this example, the value of R is the number of PMI subbands per CSI subband.

[0051] According to some aspects, Table 1 discussed above is updated as shown below in Table 2. In one example, for a small BWP (e.g., a BWP having less than a threshold number of PRBs (e.g., less than a threshold number (e.g., 24 PRBs)), the CSI subband size is the same as the size of the BWP. In this example, the network (e.g., base station 101 and / or a network associated with base station 101) can configure the csi-ReportingBand for the small BWP as well. [Table 2]

[0052] As discussed above, the CSI report configuration message may also include one or more parameters that indicate the reporting granularity in the frequency domain. For example, the CSI report configuration message may include a.cqi-FormatIndicator: wideband or subband channel quality indicator (CQI); b. pmi-FormatIndicator: wideband or subband precoding matrix indicator (PMI), c.csi-ReportingBand: Sub-band configuration may include:

[0053] According to some aspects, for Rel-15 Type I CSI and Rel-15 Type II CSI, when the UE 105 supports CSI reporting for a small BWP (e.g., a BWP with less than a threshold number of PRBs (e.g., 24 PRBs)), the UE 105 reports only the wideband PMI and the wideband CQI based on the entire BWP. In other words, the network (e.g., the base station 101 and / or a network associated with the base station 101) can configure the cqi-FormatIndicator to the wideband CQI and the pmi-FormatIndicator to the wideband PMI. The network can communicate these values ​​to the UE 105, for example, using RRC message(s). In this example, the network does not configure the sub-band CQI or the sub-band PMI. Additionally or alternatively, the UE 105 can be configured to report only the wideband PMI and the wideband CQI based on the entire BWP without instructions from the base station 101.

[0054] According to some aspects, for Rel-16 Type II CSI, when the UE 105 supports CSI reporting for a small BWP (e.g., a BWP with less than a threshold number of PRBs (e.g., 24 PRBs)), the UE 105 reports a wideband CQI based on the entire BWP. In this example, the UE 105 does not report sub-band CQI. Additionally, for PMI, the UE 105 can use a different number of PMI sub-bands. In one example, the number of PMI sub-bands is 1, and the PMI reporting is based on the entire BWP. Alternatively, the number of sub-bands is 2. In this example, if the BWP has an even number of PRBs, both PMI sub-bands are

number

number

number

[0055] According to some examples, for a small BWP (e.g., a BWP with less than a threshold number of PRBs (e.g., 24 PRBs)), the csi-ReportingBand in the CSI Report Configuration message may not be configured. Additionally or alternatively, the csi-ReportingBand may be configured, but the csi-ReportingBand bitmap includes a value of "0" for all bits in the csi-ReportingBand bitmap. In these examples, the UE 105 may consider the csi-ReportingBand to be in error and not report the CSI. Alternatively, the UE 105 may report only the wideband PMI and wideband CQI. For example, for Rel-15 Type I and Rel-15 Type II, the UE 105 can use the entire BWP to measure and report the CSI. For Rel-16 types, the number of PMI subbands can be either 1 or R, where R is either 1 or 2.

[0056] According to some examples, for a small BWP (e.g., a BWP with less than a threshold number of PRBs (e.g., 24 PRBs)), the csi-ReportingBand may be configured with only one subband (e.g., only one bit is set to the value “1” in the bitmap). In this example, for Rel-15 Type I and Rel-15 Type II, the UE 105 may report only the wideband PMI and the wideband CQI. For example, the UE 105 may ignore the cqi-FormatIndicator and pmi-FormatIndicator received in the CSI Report Configuration message. Additionally or alternatively, the UE 105 may only expect the cqi-FormatIndicator to be set to the wideband CQI and the pmi-FormatIndicator to be set to the wideband PMI. Designs for Rel-16 types when the number of subbands is low are discussed in more detail below.

[0057] According to some aspects, Rel-16 Type II provides a reduction in CSI reporting overhead. When a large number of subbands are used in a CSI report, the overhead can be large. In the CSI reporting method in Rel-16 Type II, compression mechanism(s) are used to reduce the overhead. However, when the number of subbands is small, the compression used in Rel-16 Type II may produce undesirable results (e.g., CSI reports that are ineffective, inaccurate, and / or not useful to the base station).

[0058] In some examples of Rel-16 Type II CSI reporting, the number of CSI subbands, N SB can be between 1 and 19. The number of PMI sub-bands is N≈R * N SB where R may be 1 or 2. In some examples, the value of R is determined by the network (e.g., base station 101 and / or a network associated with base station 101). The number of the selected frequency reference is determined by the parameter p vThe number of selected frequency references may depend on

number

[0059] Table 3 below shows the spatial reference number L and parameter p v , and provides one exemplary setup including eight configurations for different values ​​of the parameter β. [Table 3]

[0060] However, as discussed above, when the number of subbands is small, some of the parameter settings are not reasonable based on the number of subbands. As a non-limiting example, for a small number of subbands and using the parameters in Table 3, the parameter k0 may be calculated to have a value of 1. However, a value of 1 for the parameter k0 is invalid because, to report each of the layers, the UE 105 needs to report at least two non-zero coefficients per layer to cover vertical and horizontal polarizations. Therefore, the compression used in Rel-16 Type II may produce undesirable results (e.g., ineffective, inaccurate, and / or not useful CSI reports to the base station).

[0061] According to some aspects, systems and methods are provided for CSI reporting (e.g., for Rel-16 Type II CSI) when the number of subbands is small, such that the SCI reporting does not include the points discussed above.

[0062] According to some aspects, in Rel-16 Type II CSI, CSI is reported with a certain minimum configuration. In other words, before generating and / or transmitting a CSI report, the UE 105 can determine whether the minimum configuration is met. If the minimum configuration is met, the UE 105 can generate and transmit a CSI report. However, if the minimum configuration is not met, the UE 105 does not generate and transmit a CSI report. According to some examples, during the exemplary initial communication (or any other initial access) discussed above, the UE 105 can communicate the minimum configuration to the base station 101.

[0063] According to some aspects, the minimum configuration may include the obtained minimum number of non-zero coefficients as indicated by the parameter k0 discussed above. For example, if the rank indicator (RI) is 1 or 2, the minimum value of the parameter k0 is 2. In other words, if k0<2, the UE 105 does not transmit a CSI report for Rel-16 Type II (the UE 105 does not report Type II CSI). As discussed above, the RI may be one of the reporting parameters in the CSI report by the UE 105. The base station 101 may use the received RI to select a transmission layer for downlink data transmission.

[0064] Additionally or alternatively, when RI is 3, the minimum value of parameter k0 is 3. In other words, when k0=2, UE 105 can transmit a CSI report for Rel-16 Type II associated with RI=1 or 2 (UE 105 reports an RI=1 / 2 layer CSI report). In this example, UE 105 does not transmit a CSI report for Rel-16 Type II associated with RI=3 or 4 (UE 105 does not report an RI=3 / 4 layer CSI report).

[0065] Additionally or alternatively, when RI is 4, the minimum value of parameter k0 is 4. In other words, when k0=3, UE 105 can transmit a CSI report for Rel-16 Type II associated with RI=1, 2, or 3 (UE 105 reports an RI=1 / 2 / 3 layer CSI report). In this example, UE 105 does not transmit a CSI report for Rel-16 Type II associated with RI=4 (UE 105 does not report an RI=4 layer CSI report).

[0066] According to some aspects, the minimum configuration may be a minimum number N of CSI subbands based on the parameter configuration. SB The minimum number of CSI subbands, NSB can determine the resulting minimum number of non-zero coefficients, as indicated by the parameter k0. As discussed above, the number of PMI subbands is N≈R * N SB where R may be 1 or 2. In some examples, the value of R is determined by the network (e.g., the base station 101 and / or a network associated with the base station 101). The number of the selected frequency reference is determined by the parameter p v The number of selected frequency references may depend on

number

[0067] According to some aspects, the minimum configuration may include, based on the parameter configuration, a minimum number of spatial criteria L. The minimum number of spatial criteria L may determine the resulting minimum number of non-zero coefficients, as indicated by the parameter k0.

[0068] As discussed above, one example of a minimum configuration is to determine the minimum number of CSI subbands, N, based on the parameter configuration. SBAccording to some aspects, the minimum number of CSI subbands may be configured by the UE 105 and transmitted to the base station 101 as a capability of the UE 105. Additionally or alternatively, the minimum number of CSI subbands may be configured, for example, in a CSI report configuration message. For example, the minimum number of CSI subbands may be configured explicitly or implicitly, for example, by the csi-ReportingBand in the CSI report configuration message. According to some aspects, the number of CSI subbands is the number of bits with value "1" in the bitmap of the csi-ReportingBand. This may apply to the cases where R=1 and R=2.

[0069] Table 4 below shows the minimum number of sub-bands, N SB As an example, the minimum number of sub-bands N SB Based on Table 3 above, [Table 4]

[0070] According to some examples, for configuration 1 (paramCombination-r16=1), to support up to rank-2 (RI=2) CSI reports, the minimum number of CSI subbands is 5. In these examples, to support up to rank-3 (RI=3) CSI reports, the minimum number of CSI subbands is 9. And to support up to rank-4 (RI=4) CSI reports, the minimum number of CSI subbands is 13.

[0071] According to some examples, for configuration 2 (paramCombination-r16=2), to support up to rank-3 (RI=3) CSI reports, the minimum number of CSI subbands is 5. In these examples, to support up to rank-4 (RI=4) CSI reports, the minimum number of CSI subbands is 5.

[0072] According to some examples, for configuration 3 (paramCombination-r16=3), to support up to rank-3 (RI=3) CSI reports, the minimum number of CSI subbands is 5. In these examples, to support up to rank-4 CSI reports, the minimum number of CSI subbands is 5.

[0073] 2 is a block diagram of an example system 200 of an electronic device implementing a mechanism for designing New Radio (NR) multiple-input multiple-output (MIMO) channel state information (CSI) for a small bandwidth portion (BWP) and / or a small number of subbands in accordance with some aspects of the present disclosure. System 200 may be any of the electronic devices of system 100 (e.g., base station 101, UE 105). System 200 includes a processor 210, one or more transceivers 220, a communications infrastructure 240, memory 250, an operating system 252, an application 254, and one or more antennas 260. The illustrated system is provided as an example portion of system 200, which may include other circuit(s) and subsystem(s). Also, while the components of system 200 are illustrated as separate components, aspects of the present disclosure may include any combination of these components, fewer components, or more components.

[0074] Memory 250 may include random access memory (RAM) and / or cache and may include control logic (e.g., computer software) and / or data. Memory 250 may include other storage devices or memories, such as, but not limited to, a hard disk drive and / or a removable storage device / unit. According to some examples, operating system 252 may be stored in memory 250. Operating system 252 may manage the transfer of data from memory 250 and / or one or more applications 254 to processor 210 and / or one or more transceivers 220. In some examples, operating system 252 maintains one or more network protocol stacks (e.g., an Internet protocol stack, a cellular protocol stack, etc.), which may include several logic layers. At a corresponding layer of the protocol stack, operating system 252 includes control mechanisms and data structures for performing functions associated with that layer.

[0075] According to some examples, applications 254 may be stored in memory 250. Applications 254 may include applications (e.g., user applications) used by wireless system 200 and / or a user of wireless system 200. Applications in applications 254 may include applications such as, but not limited to, Siri™, FaceTime™, radio streaming, video streaming, remote control, and / or other user applications.

[0076] System 200 may also include a communications infrastructure 240. Communications infrastructure 240 may provide communications between, for example, processor 210, one or more transceivers 220, and memory 250. In some implementations, communications infrastructure 240 may be a bus. Processor 210, together with instructions stored in memory 250, performs operations that enable system 200 of system 100 to implement mechanisms for NR MIMO CSI for a small BWP and / or a small number of subbands, as described herein. Additionally or alternatively, one or more transceivers 220 perform operations that enable system 200 of system 100 to implement mechanisms for NR MIMO CSI for a small BWP and / or a small number of subbands, as described herein.

[0077] The one or more transceivers 220 transmit and receive communication signals that support mechanisms for NR MIMO CSI for a small BWP and / or a small number of subbands. Additionally, the one or more transceivers 220 transmit and receive communication signals that support mechanisms for measuring communication link(s) and generating and transmitting CSI reports. According to some aspects, the one or more transmitters 220 may be coupled to an antenna 260. The antenna 260 may include one or more antennas, which may be of the same or different types. The one or more transceivers 220 enable the system 200 to communicate with other devices, which may be wired and / or wireless. In some examples, the one or more transceivers 220 may include processors, controllers, radios, sockets, plugs, buffers, and similar circuits / devices used for connecting to and communicating in a network. According to some examples, the one or more transceivers 220 include one or more circuits for connecting to and communicating in a wired and / or wireless network.

[0078] According to some aspects of the present disclosure, the one or more transceivers 220 may include a cellular subsystem, a WLAN subsystem, and / or a Bluetooth™ subsystem, each including their own radio transceiver and protocol(s), as would be understood by one of ordinary skill in the art based on the discussion provided herein. In some implementations, the one or more transceivers 220 may include more or fewer systems for communicating with other devices.

[0079] In some examples, the one or more transceivers 220 may include one or more circuits (including a WLAN transceiver) for enabling connection(s) and communication over a WLAN network, such as, but not limited to, a network based on the standards set forth in IEEE 802.11.

[0080] Additionally or alternatively, one or more transceivers 220 may include one or more circuits (including a Bluetooth™ transceiver) to enable connection(s) and communication based on, for example, the Bluetooth™ protocol, the Bluetooth™ Low Energy protocol, or the Bluetooth™ Low Energy Long Range protocol. For example, transceiver 220n may include a Bluetooth™ transceiver.

[0081] Additionally, the one or more transceivers 220 may include one or more circuits (including a cellular transceiver) for connecting to and communicating in a cellular network. Cellular networks may include, but are not limited to, 3G / 4G / 5G networks such as Universal Mobile Telecommunications System (UMTS) and Long-Term Evolution (LTE). For example, the one or more transceivers 220 may be configured to operate in accordance with one or more of the 3GPP standards Rel-15, Rel-16, Rel-17, or later.

[0082] According to some aspects of the present disclosure, the processor 210, alone or in combination with computer instructions stored in the memory 250 and / or one or more transceivers 220, implements the methods and mechanisms discussed in this disclosure. For example, the processor 210, alone or in combination with computer instructions stored in the memory 250 and / or one or more transceivers 220, implements a mechanism for NR MIMO CSI for a small BWP. According to some aspects of the present disclosure, the processor 210, alone or in combination with computer instructions stored in the memory 250 and / or one or more transceivers 220, can receive a CSI report configuration message from a base station (e.g., the base station 101 of FIG. 1). Using the received CSI report configuration message, the processor 210 can determine that some physical resource blocks (PRBs) of a bandwidth portion (BWP) associated with the CSI report configuration message are less than a threshold number (24 PRBs, as a non-limiting example). However, the processor 210 can still generate a CSI report for the BWP and can transmit the CSI report to the base station using one or more transceivers.

[0083] According to some aspects, memory 250 may include device capabilities 256. Device capabilities 256 may include information indicating that device 200 is configured to generate CSI reports for BWPs having less than a threshold number of PRBs. Additionally or alternatively, device capabilities 256 may include information indicating one or more codebook types for which device 200 is configured to generate CSI reports for BWPs having less than a threshold number of PRBs. Additionally or alternatively, device capabilities 256 may include a minimum configuration used by device 200 to generate and / or transmit CSI reports if the minimum configuration is met (e.g., for Rel-16 Type II CSI). Device 200, for example, when operating as UE 105, may indicate its capabilities to base station 101 by transmitting the information stored as device capabilities 256. For example, during the example initial communication (or any other initial access) discussed above, device 200 may communicate its device capabilities 256 to base station 101.

[0084] Additionally or alternatively, processor 210, alone or in combination with computer instructions stored in memory 250 and / or one or more transceivers 220, implements a mechanism for NR MIMO CSI for a small number of subbands. For example, processor 210, alone or in combination with computer instructions stored in memory 250, uses transceiver 220 to receive a channel state information (CSI) report configuration message from base station 101. Processor 210 can use the CSI report configuration message to determine a parameter and compare the determined parameter with a threshold. In response to the parameter being greater than or equal to the threshold, processor 210 can generate a CSI report and can transmit the CSI report to base station 101 using transceiver 220. However, if the parameter is less than the threshold, processor 210 does not generate the CSI report.

[0085] As discussed in more detail below with respect to FIGS. 3-6, processor 210 may implement different mechanisms for implementing MIMO CSI for a small BWP and / or a small number of subbands, as discussed with respect to system 100 of FIG. 1.

[0086] FIG. 3 illustrates an example method 300 for a system (e.g., a user equipment (UE)) supporting a mechanism for implementing multiple-input multiple-output (MIMO) channel state information (CSI) for a small bandwidth portion (BWP) in accordance with some aspects of the present disclosure. For convenience and without limitation, FIG. 3 may be illustrated with reference to elements of FIGS. 1, 2, and 7. Method 300 may represent the operation of an electronic device (e.g., UE 105 of FIG. 1) implementing a mechanism for implementing multiple-input multiple-output (MIMO) channel state information (CSI) for a small bandwidth portion (BWP). Method 300 may also be performed by system 200 of FIG. 2 and / or computer system 700 of FIG. 7. However, method 300 is not limited to the specific aspects illustrated in these figures, and other systems may be used to perform the method, as will be understood by those skilled in the art. It should be understood that not all operations may be required, and that operations may not be performed in the same order as illustrated in FIG. 3.

[0087] At 302, a channel state information (CSI) report configuration message is received. For example, the UE 105 receives a CSI report message from the base station 101. The CSI report configuration message may include information for configuring the UE 105 to measure communication link(s), generate a CSI report, and transmit the CSI report to the base station 101. According to some aspects, the report configuration message may include a bandwidth portion (BWP) identifier for indicating a BWP to the UE 105 for channel measurements. The CSI report configuration message may also include a codebook configuration (and / or information associated with the codebook configuration) for the UE 105. The CSI report configuration message may also include one or more parameters indicating a scheduling method for the CSI report (e.g., whether the CSI report is periodic, aperiodic, etc.). The CSI report configuration message may also include one or more parameters indicating a reporting granularity in the frequency domain. For example, the CSI reporting configuration message may include an indicator associated with a channel quality indicator (CQI—e.g., cqi-FormatIndicator: wideband or sub-band CQI), an indicator associated with a precoding matrix indicator (PMI—e.g., pmi-FormatIndicator: wideband or sub-band PMI), and / or information associated with a sub-band configuration (e.g., csi-ReportingBand).

[0088] At 304, using the CSI report configuration message, it is determined that a number of physical resource blocks (PRBs) of a bandwidth portion (BWP) associated with the CSI report configuration message is less than a threshold number. For example, using a BWP identifier, the UE 105 determines that the number of PRBs of the BWP is less than a threshold number (24 PRBs, as a non-limiting example).

[0089] At 306, a CSI report is generated for the BWP. For example, the UE 105 generates a CSI report for the BWP based on information in the CSI report configuration message. At 308, the UE 105 can transmit the CSI report to the base station 101, and the base station 101 can adapt its data transmission(s) to the UE 105 based on the CSI report.

[0090] In some example aspects, the method 300 may also include transmitting a message to the base station 101 indicating that the UE 105 is capable of and configured to generate a CSI report for a BWP (having a number of PRBs less than a threshold number). Additionally or alternatively, the message from the UE 105 to the base station 101 may further indicate one or more codebook types for which the UE 105 is capable of and configured to generate a CSI report for a BWP. According to some examples, the CSI report is generated for at least one of a 3rd Generation Partnership Project (3GPP) Release 15 (Rel-15) Type-I single-panel CSI codebook, a Rel-15 Type-I multi-panel CSI codebook, a Rel-15 Type-II CSI codebook, a Rel-15 Type-II port-selection CSI codebook, a Release 16 (Rel-16) Type-II CSI codebook, or a Rel-16 Type-II port-selection CSI codebook. In some examples, the network (e.g., base station 101 and / or a network associated with base station 101) may only be able to configure UE 105 to generate CSI reports for a subset of six CSI codebooks (Release 15 (Rel-15) Type I single-panel CSI codebook, Rel-15 Type I multi-panel CSI codebook, Rel-15 Type II CSI codebook, Rel-15 Type II port-selection CSI codebook, Release 16 (Rel-16) Type II CSI codebook, and Rel-16 Type II port-selection CSI codebook).

[0091] According to some aspects, a CSI report generated and transmitted by the UE 105 may be associated with one subband, and the CSI report may include a wideband channel quality indicator (CQI) and a wideband precoding matrix indicator (PMI). In some examples, the size of the subband is equal to the size of the BWP.

[0092] In some examples, a CSI report is associated with one subband for a precoding matrix indicator (PMI), and the PMI report is based on the entire BWP. Additionally or alternatively, a CSI report may be associated with two subbands for a precoding matrix indicator (PMI). In this example, if the number of PRBs in the BWP is even, the number of PRBs in each of the two subbands is half the number of PRBs in the BWP. However, if the number of PRBs in the BWP is odd, one of the two subbands has one less PRB than the other of the two subbands.

[0093] According to some aspects, if the csi-ReportingBand in the CSI report configuration message is not configured, the UE 105 can determine that an error has occurred. Additionally or alternatively, the UE 105 can report CSI including a wideband CQI and a wideband PMI.

[0094] According to some aspects, if the csi-ReportingBand of the CSI report configuration message has a bitmap with a value of 0 for each of the bits of the bitmap, the UE 105 can determine that an error has occurred or can generate a CSI report that includes a wideband CQI and a wideband PMI.

[0095] FIG. 4 illustrates an example method 400 for a system (e.g., a base station) supporting a mechanism for implementing multiple-input multiple-output (MIMO) channel state information (CSI) for a small bandwidth portion (BWP) in accordance with some aspects of the present disclosure. For convenience and without limitation, FIG. 4 may be illustrated with reference to elements of FIGS. 1, 2, and 7. Method 400 may represent the operation of an electronic device (e.g., base station 101 of FIG. 1) implementing a mechanism for implementing multiple-input multiple-output (MIMO) channel state information (CSI) for a small bandwidth portion (BWP). Method 400 may also be performed by system 200 of FIG. 2 and / or computer system 700 of FIG. 7. However, method 400 is not limited to the specific aspects illustrated in these figures, and other systems may be used to perform the method, as will be understood by those skilled in the art. It should be understood that not all operations may be required, and that operations may not be performed in the same order as illustrated in FIG. 4.

[0096] At 402, a message is received from the UE 105, e.g., at the base station 101, indicating that the UE 105 is configured to generate channel state information (CSI) for a bandwidth portion (BWP) having less than a threshold number of physical resource blocks (PRBs). For example, the base station 101 receives the capabilities of the UE 105. The message may indicate that the UE 101 is capable of and configured to generate a CSI report for the BWP (having less than the threshold number of PRBs). Additionally or alternatively, the message may further indicate one or more codebook types for which the UE 105 is capable of and configured to generate a CSI report for the BWP.

[0097] At 404, a CSI report configuration message is transmitted to the UE 105. The CSI report configuration message may include a BWP identifier indicating a BWP having less than a threshold number of PRBs. According to some aspects, the base station 101 generates the CSI report configuration message based at least in part on the capabilities of the UE 105.

[0098] At 406, the base station 101 may receive a CSI report for the BWP from the UE 105. The CSI report may include, for example, information associated with the downlink communication link(s) between the base station 101 and the UE 105. At 408, the base station 101 may adapt its data transmission(s) to the UE 105 based on the received CSI report.

[0099] FIG. 5 illustrates an example method 500 for a system (e.g., a user equipment (UE)) supporting mechanisms for implementing multiple-input multiple-output (MIMO) channel state information (CSI) for a small number of subbands in accordance with certain aspects of the present disclosure. For convenience and without limitation, FIG. 5 may be illustrated with reference to elements of FIGS. 1, 2, and 7. Method 500 may represent operations of an electronic device (e.g., UE 105 of FIG. 1) implementing mechanisms for implementing multiple-input multiple-output (MIMO) channel state information (CSI) for a small number of subbands. Method 500 may also be performed by system 200 of FIG. 2 and / or computer system 700 of FIG. 7. However, method 500 is not limited to the specific aspects illustrated in these figures, and other systems may be used to perform the method, as will be understood by those skilled in the art. It should be understood that not all operations may be required, and that operations may not be performed in the same order as illustrated in FIG. 5.

[0100] At 502, a channel state information (CSI) reporting configuration message is received. For example, the UE 105 receives the CSI reporting configuration message from a base station.

[0101] At 504, the UE 105 may use the received CSI report configuration message to determine parameters. Using the determined parameters and thresholds, the UE 105 may determine whether to generate and transmit a CSI report. In some examples, the UE 105 generates and transmits a CSI report with a certain minimum configuration. In other words, before generating and / or transmitting a CSI report, the UE 105 may determine whether the minimum configuration is met. If the minimum configuration is met, the UE 105 may generate and transmit a CSI report. However, if the minimum configuration is not met, the UE 105 does not generate and transmit a CSI report.

[0102] At 506, the determined parameter is compared to a threshold. If the parameter is greater than or equal to the threshold, the UE 105 generates a CSI report at 508. In some examples, the CSI report is generated for a Release 16 (Rel-16) Type II codebook. However, if the parameter is less than the threshold, the UE 105 does not generate a CSI report.

[0103] At 510, the UE 105 may transmit a CSI report to the base station 101, and the base station 101 may adapt its data transmission(s) to the UE 105 based on the CSI report.

[0104] According to some aspects, the parameter may include a maximum number of non-zero coefficients. In other words, the minimum configuration may include the resulting minimum number of non-zero coefficients, as indicated by k discussed above. In this example, the threshold may have a value of 2 if the rank indicator (RI) has a value of 1 or 2, may have a value of 3 if the RI has a value of 3, or may have a value of 4 if the RI has a value of 4.

[0105] According to some aspects, the CSI report configuration message can include reporting band information, and the parameter is a number of CSI subbands determined from the reporting band information. For example, the reporting band information includes a bitmap, and the number of CSI subbands is determined based on a number of bits having a value of 1 in the bitmap.

[0106] According to some aspects, the threshold value includes a minimum number of CSI subbands. In other words, according to some aspects, the minimum configuration may be a minimum number N of CSI subbands based on the parameter configuration. SB In this example, the threshold may have a value of 5 if the rank indicator (RI) has a value of 1 or 2, may have a value of 9 if the RI has a value of 3, or may have a value of 13 if the RI has a value of 4. Additionally or alternatively, the threshold may have a value of 5 if the rank indicator (RI) has a value of 3 or 4.

[0107] According to some aspects, the UE 105 can transmit a message to the base station 101 that includes a threshold value used by the UE 105 to determine whether to generate a CSI report. For example, during the example initial communication (or any other initial access) discussed above, the UE 105 can communicate a minimum configuration (e.g., a threshold value used to determine whether to generate a CSI report) to the base station 101.

[0108] FIG. 6 illustrates an example method 600 for a system (e.g., a base station) supporting a mechanism for implementing multiple-input multiple-output (MIMO) channel state information (CSI) for a small number of subbands in accordance with certain aspects of the present disclosure. For convenience and without limitation, FIG. 6 may be illustrated with reference to elements of FIGS. 1, 2, and 7. Method 600 may represent the operation of an electronic device (e.g., base station 101 of FIG. 1) implementing a mechanism for implementing multiple-input multiple-output (MIMO) channel state information (CSI) for a small number of subbands. Method 600 may also be performed by system 200 of FIG. 2 and / or computer system 700 of FIG. 7. However, method 600 is not limited to the specific aspects illustrated in these figures, and other systems may be used to perform the method, as will be understood by those skilled in the art. It should be understood that not all operations may be required, and that operations may not be performed in the same order as illustrated in FIG. 6.

[0109] At 602, a message including a threshold used by the UE to determine whether to generate a CSI report is received from UE 105, e.g., at base station 101. For example, during the example initial communication (or any other initial access) discussed above, base station 101 receives from UE 105 a minimum configuration (e.g., threshold) used by UE 105 to determine whether to generate a CSI report.

[0110] At 604, a CSI report configuration message is transmitted to the UE 105. The CSI report configuration message may include information used by the UE 105 to determine one or more parameters used to determine whether to generate a CSI report. For example, the CSI report configuration message may include report band information used by the UE 105 to determine the one or more parameters. For example, the report band information may include a bitmap. According to some aspects, the base station 101 generates the CSI report configuration message based at least in part on the capabilities of the UE 105 reported in the message received at 602.

[0111] At 606, the base station 101 may receive from the UE 105 a CSI report generated by the UE 105. The CSI report includes, for example, information associated with the downlink communication link(s) between the base station 101 and the UE 105. At 608, the base station 101 may adapt its data transmission(s) to the UE 105 based on the received CSI report.

[0112] Various aspects may be implemented using one or more computer systems, such as, for example, computer system 700 shown in FIG. 7 . Computer system 700 can be any known computer capable of performing the functions described herein, such as devices 101, 105 of FIG. 1 or device 200 of FIG. 2 . Computer system 700 includes one or more processors (also referred to as central processing units or CPUs), such as processor 704. Processor 704 is connected to a communications infrastructure 706 (e.g., a bus). Computer system 700 also includes user input / output device(s) 703, such as a monitor, keyboard, pointing device, etc., which communicate with communications infrastructure 706 via user input / output interface(s) 702. Computer system 700 also includes a main or primary memory 708, such as random access memory (RAM). Main memory 708 may include one or more levels of cache. Main memory 708 stores control logic (e.g., computer software) and / or data.

[0113] Computer system 700 may also include one or more secondary storage devices or memories 710. Secondary memory 710 may include, for example, a hard disk drive 712 and / or a removable storage device or drive 714. Removable storage drive 714 may be a floppy disk drive, a magnetic tape drive, a compact disk drive, an optical storage device, a tape backup device, and / or any other storage device / drive.

[0114] The removable storage drive 714 can interact with a removable storage unit 718. The removable storage unit 718 includes a computer-usable or computer-readable storage device on which computer software (control logic) and / or data is stored. The removable storage unit 718 may be a floppy disk, magnetic tape, compact disk, DVD, optical storage disk, and / or any other computer data storage device. The removable storage drive 714 reads from and / or writes to the removable storage unit 718 in well-known fashion.

[0115] According to some aspects, secondary memory 710 may include other means, intermediaries, or other techniques for allowing computer programs and / or other instructions and / or data to be accessed by computer system 700. Such means, intermediaries, or other techniques may include, for example, removable storage unit 722 and interface 720. Examples of removable storage unit 722 and interface 720 may include a program cartridge and cartridge interface (such as those found in video game devices), a removable memory chip (such as an EPROM or PROM) and associated socket, a memory stick and USB port, a memory card and associated memory card slot, and / or any other removable storage unit and associated interface.

[0116] Computer system 700 may further include a communications or network interface 724. Communications interface 724 enables computer system 700 to communicate and interact with any combination of remote devices, remote networks, remote entities, etc. (individually and collectively indicated by reference numeral 728). For example, communications interface 724 may enable computer system 700 to communicate with remote devices 728 via communications path 726, which may be wired and / or wireless and may include any combination of a LAN, a WAN, the Internet, etc. Control logic and / or data may be transmitted to and from computer system 700 via communications path 726.

[0117] The operations in the aforementioned aspects may be implemented in a wide variety of configurations and architectures. Thus, some or all of the operations in the aforementioned aspects may be performed in hardware, software, or both. In some aspects, a tangible, non-transitory apparatus or article of manufacture is also referred to herein as a computer program product or program storage device that includes a tangible, non-transitory computer-usable or readable medium having control logic (software) stored thereon. This includes, but is not limited to, computer system 700, main memory 708, secondary memory 710, removable storage unit 718, and removable storage unit 722, as well as tangible articles of manufacture embodying any combination of the foregoing. Such control logic, when executed by one or more data processing devices (such as computer system 700), causes such data processing devices to operate as described herein.

[0118] Based on the teachings contained herein, it will be apparent to one skilled in the relevant art(s) how to make and use aspects of the present disclosure using data processing devices, computer systems and / or computer architectures other than those shown in Figure 7. In particular, aspects may operate with software, hardware, and / or operating system implementations other than those described herein.

[0119] It is understood that the Detailed Description section, and not the Summary and Abstract sections, is intended to be used to interpret the claims. The Summary and Abstract sections may describe one or more exemplary aspects of the disclosure, but not all of the exemplary aspects of the disclosure, as contemplated by the inventor(s), and therefore, the Summary and Abstract sections are not intended to limit the scope of the disclosure or the appended claims in any way.

[0120] While the present disclosure is described herein with reference to exemplary embodiments for exemplary fields and applications, it should be understood that the present disclosure is not limited to the exemplary embodiments. Other embodiments and variations of embodiments are possible and are within the scope and spirit of the present disclosure. For example, without limiting the generality of this paragraph, embodiments are not limited to the software, hardware, firmware, and / or entities shown in the figures and / or described herein. Moreover, embodiments (whether or not explicitly described herein) have significant utility in fields and applications beyond the examples described herein.

[0121] Aspects are described herein in terms of functional building blocks that illustrate specific functional implementations and relationships. The boundaries of these functional building blocks are arbitrarily defined herein for convenience of description. Alternative boundaries may be defined so long as the specific functions and relationships (or their equivalents) are appropriately performed. In addition, alternative aspects may execute functional blocks, steps, operations, methods, etc. using an order different from that described herein.

[0122] References herein to "one embodiment," "one embodiment," "exemplary embodiment," or similar phrases indicate that the described embodiment may include a particular feature, structure, or characteristic, but not all embodiments necessarily include the particular feature, structure, or characteristic. Also, such phrases do not necessarily refer to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in the context of one embodiment, it is within the knowledge of one of ordinary skill in the relevant art(s) to incorporate such particular feature, structure, or characteristic into other aspects, whether or not explicitly mentioned or described herein.

[0123] The breadth and scope of the present disclosure should not be limited by any of the above-described exemplary aspects, but should be defined only in accordance with the following claims and their equivalents.

[0124] It is fully understood that use of personal information should comply with generally recognized privacy policies and practices that meet or exceed industry or government requirements for maintaining user privacy. In particular, personal information data should be managed and handled in a manner that minimizes the risk of unintended or unauthorized access or use, and the nature of permitted uses should be clearly indicated to users.

Claims

1. a transceiver configured to communicate with a base station; a processor communicatively coupled to the transceiver, the processor: receiving a channel state information (CSI) report configuration message from the base station using the transceiver; determining, using the CSI report configuration message, that a number of physical resource blocks (PRBs) of a bandwidth portion (BWP) associated with the CSI report configuration message is less than a threshold number; generating a CSI report for the BWP for only Release-15 (Rel-15) Type-I CSI, without reporting for Rel-15 Type-II CSI and without reporting for Rel-16 Type-I CSI; transmitting the CSI report to the base station using the transceiver; The UE is configured to:

2. The UE of claim 1 , wherein the CSI report includes a wideband channel quality indicator (CQI) and a wideband precoding matrix indicator (PMI).

3. The UE of claim 1 , wherein the CSI report includes a wideband channel quality indicator (CQI) and a wideband precoding matrix indicator (PMI) for an entire BWP.

4. The UE of claim 1 , wherein the CSI report is associated with one subband.

5. The UE of claim 4 , wherein the size of the one subband is equal to the size of the BWP.

6. The UE of claim 1 , wherein the CSI report is associated with one subband for the PMI.

7. The UE of claim 1 , wherein the CSI report is associated with two sub-bands for the PMI.

8. In response to the number of PRBs in the BWP being an even number, the number of PRBs in each of the two sub-bands is half the number of PRBs in the BWP; 8. The UE of claim 7, wherein, in response to the number of PRBs in the BWP being odd, one of the two subbands has one less PRB than the other of the two subbands.

9. 2. The UE of claim 1, wherein, in response to a csi-ReportingBand of the CSI report configuration message being not configured or having the bitmap with a value of 0 for each of its bits, the processor is configured to determine that an error has occurred or to generate the CSI report including a wideband channel quality indicator (CQI) and a wideband precoding matrix indicator (PMI).

10. The UE of claim 1 , wherein the threshold number is 24 PRBs.

11. receiving a channel state information (CSI) report configuration message from a base station by a user equipment (UE); determining, using the CSI report configuration message, that a number of physical resource blocks (PRBs) in a bandwidth portion (BWP) associated with the CSI report configuration message is less than a threshold number; generating a CSI report for the BWP for only Release-15 (Rel-15) Type-I CSI, without reporting for Rel-15 Type-II CSI and without reporting for Rel-16 Type-I CSI; transmitting the CSI report to the base station; A method comprising:

12. a transceiver configured to communicate with a user equipment (UE); a processor communicatively coupled to the transceiver, the processor: Using the transceiver, transmit a channel state information (CSI) report configuration message to the UE using a bandwidth portion (BWP) having less than a threshold number of physical resource blocks (PRBs); receiving CSI reports for only Release-15 (Rel-15) Type-I CSI, without reporting for Rel-15 Type-II CSI and without reporting for Rel-16 Type-I CSI; The base station is configured to:

13. The base station of claim 12 , wherein the CSI report is associated with one sub-band.

14. The base station according to claim 13 , wherein the size of the one sub-band is equal to the size of the BWP.

15. The base station of claim 12 , wherein the CSI report for an entire BWP includes a wideband channel quality indicator (CQI) and a wideband precoding matrix indicator (PMI).

16. The base station of claim 12 , wherein the CSI report includes a wideband channel quality indicator (CQI) and a wideband precoding matrix indicator (PMI).

17. the CSI report is associated with two sub-bands for the PMI; In response to the number of PRBs in the BWP being an even number, the number of PRBs in each of the two sub-bands is half the number of PRBs in the BWP; 13. The base station of claim 12, wherein in response to the number of PRBs in the BWP being odd, one of the two subbands has one less PRB than the other of the two subbands.

18. The base station of claim 12 , wherein the processor is further configured to adapt data transmission to the UE based on the CSI report.

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