Channel state information measurement adaptation to maximum multiple-input multiple-output layers

Abstract

This application provides techniques for adapting channel state information measurements for maximum multiple-input multiple-output (MIMO) layers. A method that can be performed by a user equipment (UE) includes: receiving a first CSI report configuration comprising one or more first channel state information (CSI) reference signal (CSI-RS) resources, wherein each first CSI-RS resource comprises a first resource set; determining a first subset of resources to report the first CSI on based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and reporting the first CSI to a base station (BS), wherein the first CSI is based on the determined first resource subset.

Description

Adjustment of channel state information measurement for maximum multiple input multiple output layers This patent application claims the benefit of priority to U.S. Provisional Patent Application No. 62 / 891,665, filed August 26, 2019, which has been assigned to the assignee of this application and is incorporated herein by reference in its entirety, as fully set forth below and for all applicable purposes. The present invention relates to wireless communication systems, and more specifically, to techniques for reducing the measurement and calculation of Channel State Information (CSI) by user equipment (UEs) assigned to receive a reduced number of multiple-input multiple-output (MIMO) layers. Wireless communication systems are widely deployed to provide various telecommunications services such as telephone, video, data, messaging, and broadcasting. These wireless communication systems can employ multiplexing access technologies that support communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power). Examples of such multiplexing access systems include 3GPP Long Term Evolution (LTE) systems, LTE-A (LTE-A) systems, Code Division Multiplexing (CDMA) systems, Time Division Multiplexing (TDMA) systems, Frequency Division Multiplexing (FDMA) systems, Orthogonal Frequency Division Multiplexing (OFDMA) systems, Single Carrier Frequency Division Multiplexing (SC-FDMA) systems, and Time Division Synchronous Code Division Multiplexing (TD-SCDMA) systems. These multiplexing access technologies have been adopted in various telecommunications standards to provide a common protocol that enables different wireless devices to communicate at the city, country, region, and even global levels. New radio (e.g., 5G NR) is an example of an emerging telecommunications standard. NR is an enhancement set of the LTE mobile service standard released by 3GPP. NR is designed to better support mobile broadband internet access by improving spectrum efficiency, reducing costs, improving service, utilizing new spectrum, and using OFDMA with cyclic prefixes (CP) on the downlink (DL) and uplink (UL). To this end, NR supports beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation. However, with the continued growth in demand for mobile broadband access, there is a need for further improvements to NR and LTE technologies. Preferably, these improvements should be applicable to other multiplexing access technologies and telecommunications standards that employ these technologies. The systems, methods, and apparatuses described in this application have several states, with no single state solely responsible for its desired properties. Without limiting the scope of the application as expressed in the subsequent claims, some features will now be briefly discussed. After considering this discussion, and especially after reading the section entitled "Detailed Description," it will be understood how the features of the application provide advantages, including reduced power consumption due to reduced Channel State Information (CSI) measurements, calculations, and reporting when the UE is assigned to receive a reduced maximum number of Multiple-Input Multiple-Output (MIMO) layers. Some versions provide a method for performing wireless communication by a user equipment (UE). In general, the method includes: receiving a first CSI report configuration including one or more first channel state information (CSI) reference signal (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set; determining a first subset of resources to report the first CSI on based on an indication of a maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and reporting the first CSI to a base station (BS), wherein the first CSI is based on the determined first resource subset. Some aspects of this case relate to an apparatus for wireless communication. In general, the apparatus includes a memory and at least one processor coupled to the memory, the memory and the at least one processor being configurable or configured to: receive a first CSI report configuration including one or more first CSI-RS resources, wherein each first CSI-RS resource includes a first resource set; determine a first subset of resources to report the first CSI on based on an indication of a maximum number of MIMO layers that the apparatus is expected to receive; and report the first CSI to a base station (BS), wherein the first CSI is based on the determined first resource subset. Some aspects of this case relate to an apparatus for wireless communication. In general, the apparatus includes: a unit for receiving a first CSI report configuration comprising one or more first CSI-RS resources, wherein each first CSI-RS resource comprises a first resource set; a unit for determining a first subset of resources to report the first CSI on based on an indication of a maximum number of MIMO layers that the apparatus is expected to receive; and a unit for reporting the first CSI to a BS, wherein the first CSI is based on the determined first subset of resources. Some aspects of this case relate to a computer-readable medium having instructions stored thereon that, when executed by a processing system, cause the processing system to perform operations including: receiving a first CSI report configuration comprising one or more first CSI-RS resources, wherein each first CSI-RS resource comprises a first resource set; determining a first subset of resources to report the first CSI thereon based on an indication of a maximum number of MIMO layers that a device including the processing system is expected to receive; and reporting the first CSI to a BS, wherein the first CSI is based on the determined first subset of resources. Some versions provide a method for wireless communication performed by a base station (BS). In general, the method includes: sending a first CSI report configuration to a user equipment (UE) including one or more first channel state information (CSI) reference signal (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set; receiving the first CSI from the UE, wherein the first CSI is based on a first resource subset; and determining the first resource subset on which the first CSI is based based on an indication of a maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive. This case relates in certain aspects to an apparatus for wireless communication. In general, the apparatus includes a memory and at least one processor coupled to the memory, the memory and the at least one processor being configurable or configured to: send a first CSI report configuration to a UE including one or more first CSI-RS resources, wherein each first CSI-RS resource includes a first resource set; receive the first CSI from the UE, wherein the first CSI is based on a first resource subset; and determine the first resource subset on which the first CSI is based based on an indication of a maximum number of MIMO layers that the UE is expected to receive. This case relates in certain aspects to an apparatus for wireless communication. In general, the apparatus includes: units for transmitting a first CSI report configuration to a UE including one or more first CSI-RS resources, wherein each first CSI-RS resource includes a first resource set; units for receiving the first CSI from the UE, wherein the first CSI is based on a subset of the first resources; and units for determining the first resource subset on which the first CSI is based based on an indication of a maximum number of MIMO layers that the UE is expected to receive. Some aspects of this case relate to a computer-readable medium having instructions stored thereon, which, when executed by a processing system, cause the processing system to perform operations including: sending a first CSI report configuration to a UE including one or more first CSI-RS resources, wherein each first CSI-RS resource includes a first resource set; receiving the first CSI from the UE, wherein the first CSI is based on a first resource subset; and determining the first resource subset on which the first CSI is based based on an indication of the maximum number of MIMO layers that the UE is expected to receive. Some formats provide a method for performing wireless communication by a user equipment (UE). In summary, the method includes: changing the number of first available channel state information (CSI) reference signals (CSI-RS) processing units (CPUs) of the UE to a second available CPU number based on an indication of a maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and sending an indication to a base station (BS) that the UE has changed to the second available CPU number. Some aspects of this case relate to an apparatus for wireless communication. In general, the apparatus includes a memory and at least one processor coupled to the memory, the memory and the at least one processor being configurable or configured to: change from a first available number of CPUs in the apparatus to a second available number of CPUs in the apparatus based on an indication of a maximum number of MIMO layers that the apparatus is expected to receive; and send an indication to a BS that the apparatus has changed to the second available number of CPUs. Some aspects of this case relate to an apparatus for wireless communication. In general, the apparatus includes: a unit for changing from a first number of available CPUs to a second number of available CPUs based on an indication of a maximum number of MIMO layers the apparatus is expected to receive; and a unit for sending an indication to a BS that the apparatus has changed to the second number of available CPUs. Some aspects of this case relate to a computer-readable medium having instructions stored thereon that, when executed by a processing system, cause the processing system to perform operations, including: changing from a first available number of CPUs in the device to a second available number of CPUs in the device based on an indication of a maximum number of MIMO layers that a device including the processing system is expected to receive; and sending an indication to the BS that the device has changed to the second available number of CPUs. Some versions provide a method for wireless communication performed by a base station (BS). In general, the method includes: sending an indication to a user equipment (UE) of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and receiving from the UE an indication that the UE has changed from a first available channel state information (CSI) reference signal (CSI-RS) processing unit (CPU) number to a second available CPU number. Some aspects of this case relate to an apparatus for wireless communication. In general, the apparatus includes a memory and at least one processor coupled to the memory, the memory and the at least one processor being configurable or configured to: send an indication to a UE of a maximum number of MIMO layers that the UE is expected to receive; and receive from the UE an indication that the UE has changed from a first number of available CPUs to a second number of available CPUs. Some aspects of this case relate to an apparatus for wireless communication. In general, the apparatus includes: a unit for sending an indication to a UE of a maximum number of MIMO layers that the UE is expected to receive; and a unit for receiving from the UE an indication that the UE has changed from a first number of available CPUs to a second number of available CPUs. Some aspects of this case involve a computer-readable medium having instructions stored thereon, which, when executed by a processing system, cause the processing system to perform operations, including: sending an indication to a UE of a maximum number of MIMO layers that the UE is expected to receive; and receiving from the UE an indication that the UE has changed from a first number of available CPUs to a second number of available CPUs. To achieve the foregoing and related objectives, one or more states include the features fully described below and specifically pointed out in the claims. The following description and figures illustrate certain illustrative features of one or more states in detail. However, these features indicate only a few of the various ways in which the principles of the various states can be employed. This document provides apparatus, methods, processing systems, and computer-readable media for reducing channel state information (CSI) measurements and calculations performed by user equipment (UEs) assigned to receive a reduced number of multiple-input multiple-output (MIMO) layers. UE power consumption is typically highly dependent on the number of MIMO layers received by the UE. To handle a larger number of MIMO layers, a typical UE consumes significant power in both its radio frequency (RF) and baseband subsystems. In the RF subsystem, the UE activates at least the number of receiving antennas or panels used to receive MIMO signals. In the baseband subsystem, the use of MIMO decoders requires substantial power. Therefore, instructing the UE on the maximum number of MIMO layers expected to be received can be explained by enabling the UE to adjust the number of receiving antennas or panels and the baseband processing system. The following description provides examples of channel state information (CSI) measurement adaptation for the maximum MIMO layer in a communication system, without limiting the scope, applicability, or examples set forth in the request. Changes may be made to the functionality and arrangement of the elements discussed without departing from the scope of this document. Various procedures or components may be omitted, substituted, or added as appropriate in each example. For example, the described method may be performed in a different order than described, and various steps may be added, omitted, or combined. Furthermore, features described with respect to some examples may be combined with other examples. For example, an apparatus or method may be implemented using any number of the patterns set forth herein. Moreover, the scope of this document is intended to cover such apparatuses or methods implemented using structures, functions, or structures and functions other than or different from the patterns of disclosure set forth herein. It should be understood that any pattern of disclosure may be embodied by one or more elements of the request. The term "exemplary" is used herein to mean "serving as an example, illustration, or description." Any state described as "exemplary" in this document is not necessarily to be interpreted as preferred or superior to other states. Typically, any number of wireless networks can be deployed in a given geographic area. Each wireless network can support a specific Radio Access Technology (RAT) and can operate on one or more frequencies. RATs can also be referred to as radio technologies, air interfaces, etc. Frequencies can also be referred to as carriers, subcarriers, frequency channels, tones, subbands, etc. Each frequency can support a single RAT in a given geographic area to avoid interference between wireless networks with different RATs. In some cases, 5G NR RAT networks can be deployed. Figure 1 illustrates an example of a wireless communication network 100 in which the contents of this case can be implemented. For example, the wireless communication network 100 may be an NR system (e.g., a 5G NR network). As shown in Figure 1, the wireless communication network 100 may include multiple base stations (BSs) 110a-z (each of which is also individually referred to as BS 110 or collectively as BS 110 herein) and other network entities. BS 110 may provide communication coverage for a specific geographic area (sometimes referred to as a "cell"), which may be fixed or mobile depending on the location of the mobile BS 110. In some instances, BS 110 may interconnect with each other and / or with one or more other BSs or network nodes (not shown) in the wireless communication network 100 using any suitable transport network via various types of backhaul interfaces (e.g., direct physical connection, wireless connection, virtual network, etc.). In the example shown in Figure 1, BS 110a, 110b, and 110c may be macro BSs for macro cells 102a, 102b, and 102c, respectively. BS 110x may be a pico BS for pico cells 102x. BS 110y and 110z can be femtoBSs for femtocells 102y and 102z, respectively. A BS can support one or more cells. BS 110 communicates with user equipment (UE) 120a-y (each of which is also individually referred to as UE 120 or collectively as UE 120) in the wireless communication network 100. UE 120 (e.g., 120x, 120y, etc.) can be distributed throughout the wireless communication network 100, and each UE 120 can be fixed or mobile. Depending on certain configurations, BS 110 and UE 120 can be configured to adapt CSI to the MIMO layer. As shown in Figure 1, BS 110a includes CSI 112 adapted for the MIMO manager. Depending on the configuration of this application, CSI 112 adapted for the MIMO manager can be configured to: send a first CSI report configuration to the user equipment (UE) including one or more first channel state information (CSI) reference signal (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set; receive a first CSI from the UE, wherein the first CSI is based on a first resource subset; and determine the first resource subset on which the first CSI is based based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive. As shown in Figure 1, UE 120a includes an adapted CSI 122 for the MIMO manager. According to the various forms of the content of this case, the adaptation CSI 122 for the MIMO manager can be configured to: receive a first CSI report configuration including one or more first channel status information (CSI) reference signals (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set; determine a first resource subset on which to report the first CSI based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and report the first CSI to the base station (BS), wherein the first CSI is based on the determined first resource subset. The wireless communication network 100 may also include a relay station (e.g., relay station 110r) (also referred to as a repeater, etc.) that receives data and / or other information transmissions from an upstream station (e.g., BS 110a or UE 120r) and sends data and / or other information transmissions to a downstream station (e.g., UE 120 or BS 110), or relays transmissions between UEs 120 to facilitate communication between devices. Network controller 130 can be coupled to a group of BSs 110 and provide coordination and control for these BSs 110. Network controller 130 can communicate with BSs 110 via backhaul. BSs 110 can also communicate with each other via wireless or wired backhaul (e.g., directly or indirectly). Figure 2 illustrates example components of BS 110a and UE 120a (e.g., in the wireless communication network 100 of Figure 1), which can be used to implement various aspects of the present invention. At BS 110a, the transmit processor 220 can receive data from data source 212 and control information from controller / processor 240. The control information can be used for entity broadcast channel (PBCH), entity control format indicator channel (PCFICH), entity hybrid ARQ indicator channel (PHICH), entity downlink control channel (PDCCH), group common PDCCH (GC PDCCH), etc. Data can be used for entity downlink shared channel (PDSCH), etc. The processor 220 can process (e.g., encoding and symbol mapping) the data and control information separately to obtain data symbols and control symbols. The processor 220 can also generate, for example, primary synchronization signal (PSS), secondary synchronization signal (SSS), and cell-specific reference symbols (CRS). The transmit (TX) multiple-input multiple-output (MIMO) processor 230 can perform spatial processing (e.g., precoding, if applicable) on the data symbols, control symbols, and / or reference symbols, and can provide output symbol streams to modulators (MODs) 232a-232t. Each modulator 232 can (e.g., for OFDM, etc.) process the corresponding output symbol stream to obtain an output sample stream. Each modulator can further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. The downlink signal from modulators 232a-232t can be transmitted via antennas 234a-234t respectively. At UE 120a, antennas 252a-252r can receive downlink signals from BS 110 and can provide the received signals to demodulators (DEMODs) in transceivers 254a-254r respectively. Each demodulator 254 can adjust (e.g., filter, amplify, downconvert, and digitize) the corresponding received signal to obtain an input sample. Each demodulator can further process the input sample (e.g., for OFDM, etc.) to obtain received symbols. MIMO detector 256 can obtain received symbols from all demodulators 254a-254r, perform MIMO detection on the received symbols (if applicable), and provide the detected symbols. Receiver processor 258 can process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for UE 120a to data slot 260, and provide decoded control information to controller / processor 280. On the uplink, at UE 120a, the transmitting processor 264 can receive and process data from data source 262 (e.g., for the Physical Uplink Shared Channel (PUSCH)) and control information from controller / processor 280 (e.g., for the Physical Uplink Control Channel (PUCCH)). The transmitting processor 264 can also generate reference symbols for reference signals (e.g., for the Sounding Reference Signal (SRS)). Symbols from the transmitting processor 264 can be pre-encoded (if applicable) by the TX MIMO processor 266, further processed by demodulators (e.g., for SC-FDM, etc.) in transceivers 254a-254r, and transmitted to BS 110a. At BS 110a, the uplink signal from UE 120a can be received by antenna 234, processed by modulator 232, detected by MIMO detector 236 (if applicable), and further processed by receiver processor 238 to obtain decoded data and control information transmitted by UE 120a. Receiver processor 238 can provide the decoded data to data slot 239 and the decoded control information to controller / processor 240. Memory modules 242 and 282 can store data and code for BS 110a and UE 120a, respectively. Scheduler 244 can schedule the UE for data transmission on the downlink and / or uplink. For example, the controller / processor 280 and / or other processors or modules at UE 120a, or the controller / processor 240 and / or other processors or modules at BS 11a, can execute or direct the execution of programs used in the techniques described herein. For example, as shown in FIG2, the controller / processor 240 of BS 110a has a CSI 241 suitable for a MIMO manager. According to the various embodiments described herein, the CSI 241 suitable for a MIMO manager can be configured to: send a first CSI report configuration to the user equipment (UE) including one or more first channel status information (CSI) reference signal (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set; receive a first CSI from the UE, wherein the first CSI is based on a first resource subset; and determine the first resource subset on which the first CSI is based based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive. As shown in Figure 2, the controller / processor 280 of UE 120a has an adapted CSI 281 for the MIMO manager. According to the various embodiments described herein, the adapted CSI 281 for the MIMO manager can be configured to: receive a first CSI report configuration including one or more first channel state information (CSI) reference signal (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set; determine a first subset of resources to report the first CSI on based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and report the first CSI to the base station (BS), wherein the first CSI is based on the determined first resource subset. Although shown at the controller / processor, other components of UE 120a and BS 110a can be used to perform the operations described herein. In various forms of this case, from the perspective of "collision," two or more CSI report transmissions by the UE occasionally occur: they are scheduled to be sent simultaneously, for example, periodic and non-periodic CSI reports can be scheduled for transmission in the same time period (e.g., time slot or subframe). Furthermore, multiple CSI reports scheduled for simultaneous transmission may result in a payload size that is too large to fit within the Uplink Control Information (UCI) container, for example, because the sending UE is attempting to multiplex Hybrid Automatic Repeat Request (HARQ) Acknowledgment (HARQ-ACK) and / or Scheduling Request (SR) with CSI reports in the UCI. In these cases, the UE may discard or omit some CSI reports. To prioritize CSI reports, several priority rules have been defined in previously known technologies. CSI reports are first prioritized based on their temporal behavior (e.g., the dynamic level of the CSI report) and physical channel, with more dynamic reports (e.g., non-periodic reports) taking precedence over less dynamic reports (e.g., periodic reports), and reports via the Physical Uplink Shared Channel (PUSCH) taking precedence over reports via the Physical Uplink Control Channel (PUCCH). For example, non-periodic reports take precedence over semi-persistent reports on the PUSCH, which in turn take precedence over semi-persistent reports on the PUCCH, which in turn take precedence over periodic CSI reports. If multiple CSI reports with the same temporal behavior and physical channel conflict, the reports are further prioritized based on the CSI content, with beam reports (e.g., Layer 1 Reference Signal Received Power (L1-RSRP) reports) taking precedence over general CSI reports. The motivation for giving beam reports higher priority is that non-beam CSI reports are typically conditioned on the serving beam, and therefore, if the beam is incorrect, non-beam CSI reports would be useless. If further differentiation is still required, in the case of carrier aggregation (CA) operation, CSI reports are further prioritized based on the service cell corresponding to the CSI. That is, CSIs corresponding to the primary cell (PCell) take precedence over CSIs corresponding to the secondary cell (SCell). Finally, to avoid any ambiguity in sending CSI reports, a report configuration identifier (CSI) is used for each CSI report. Use reportConfigID to prioritize CSI reports. Applying the CSI priority rules described above ensures that only a single CSI report is sent in the event of a CSI report conflict, except in cases of conflict between multiple PUCCH-based CSI reports. In this case, the UE may be configured with a larger "multi-CSI" PUCCH resource, where several CSI reports can be multiplexed. When using multi-CSI PUCCH resources, as many multiplexed CSI reports as possible can be sent within the "multi-CSI" PUCCH resource, provided that the maximum UCI code rate is not exceeded. Based on previously known techniques, the rules for prioritizing CSI reports described above can be described using the following mathematical terms. Each CSI report is associated with a priority value: Pri iCSI ( y,k,c,s) = 2∙N cells ∙ M s ∙ y + N cells ∙ M s ∙ k + M s • c +s; where for non-periodic CSI reports to be carried on the PUSCH, y = 0; For semi-persistent CSI reports to be carried on the PUSCH, y = 1; For semi-persistent CSI reports to be carried on PUCCH, y = 2; and for the periodic CSI reports to be carried on PUCCH, y = 3; For CSI reports carrying L1-RSRP, k = 0; For CSI reports that do not carry L1-RSRP, k = 1; c is the service cell index, and N cells These are higher-level parameters. The value of maxNrofServingCells; s is reportConfigID, and M s These are higher-level parameters. The value of maxNrofCSI-ReportConfigurations. If the first report is associated with a Pri... iCSI ( The values ​​of y,k,c,s) are lower than the associated Pri in the second report. iCSI ( If the values ​​of y,k,c,s are used, then the first CSI report is said to take precedence over the second CSI report. In previously known technologies (e.g., New Radio (NR) or Fifth Generation (5G)), the concept of a CSI processing unit (CPU) is described, where the number of CPUs in a UE is equal to the number of simultaneous CSI calculations supported by the UE. As an example, a CPU can be viewed as a general-purpose CSI calculation engine that can process any kind of CSI report and can be implemented via software. When the calculation of a CSI report is about to take place, for example, when a UE is triggered to provide an aperiodic CSI report, or when the calculation for a periodic or semi-persistent CSI report begins, the CSI report being calculated is assigned to one or more available CPUs. If insufficient CPU is available (e.g., because the UE has already processed other CSI reports), the UE may not compute the CSI report to be assigned. Instead, the UE may report outdated CSIs, such as previously computed CSI reports stored in memory, or simply fill the CSI report with virtual bits. In this case, instead of discarding the CSI report, some content is always sent to avoid changing the rate matching procedure used for PUSCH or PUCCH transmissions, as changing the rate matching procedure can be error-prone. Therefore, the UE commits to performing calculations on each CSI report from the start of the allocation time until the last symbol of the physical channel carrying the CSI report (e.g., PUCCH or PUSCH) has been sent (at which point the signal is released). (n) 𝐶𝑃𝑈 The CPU (e.g., used for calculating CSI for later reports) has been used up to 100 CPUs. (n) 𝐶𝑃𝑈 One CPU. For aperiodic CSI reports, the initial CPU allocation time is the last symbol of the entity downlink control channel (PDCCH) that triggered the aperiodic CSI report. For periodic and semi-persistent CSI reports, CPU allocation begins from the occurrence of the last Channel State Information Reference Signal (CSI-RS) or Interference Measurement (IM) resource used to calculate the report. That is, for periodic or semi-persistent reports, it can be assumed that the UE begins calculating the CSI report as soon as it receives the last measurement resource. For non-beam-dependent CSI reports (e.g., when the reportQuantity of the CSI report is not equal to "cri-RSRP", "ssb-Index-RSRP", or "none"), the CSI report consumes as much CPU as the number of CSI-RS resources in the set of CSI-RS resources used for channel measurements. This is because, in the worst case, the UE may need to compute the complete CSI report in parallel for each CSI-RS resource so that the UE can determine which CSI-RS resource is optimal and should be selected with the corresponding CSI-RS Resource Indicator (CRI). Figure 3A is an exemplary transmission isochrona 300 according to various configurations of this case. As mentioned above, UE power consumption typically depends on the number of MIMO layers received by the UE. Therefore, in the exemplary isochrona 300, UE 120a is assigned (e.g., configured with) a first active BWP 310, where the UE is expected to receive up to two MIMO layers, e.g., L max = 2. Therefore, as shown in Figure 3B, at 330, the UE activates two of its four antennas (or panels) 252a, 252b, 252c, and 252d, namely antennas (or panels) 252c and 252d. This allows the UE to save significant power compared to having all four antennas (or panels) active. The UE can also activate a portion of its MIMO decoder based on the maximum number of MIMO layers the UE is expected to receive. Later, the UE is assigned to a second active BWP 320, where the UE is expected to receive up to four MIMO layers, such as L... max = 4. Therefore, the UE activates four antennas 252a, 252b, 252c, and 252d, as shown at 335. In some cases, the UE can receive BWP-specific CSI-RS configurations, where each CSI-RS configuration corresponds to the CSI-RS resources for which the UE will report measurements. That is, the first active BWP 310 may include a first CSI-RS configuration, and the second active BWP 320 may include a second (e.g., different) CSI-RS configuration. Therefore, when the UE is assigned to a different active BWP (e.g., switching from the first active BWP 310 to the second active BWP 320), the UE can use the new CSI-RS resource reporting configuration. In some cases, the BS can signal the new CSI-RS configuration for the BWP. That is, the UE can be assigned to the first active BWP 310 and receive a new configuration for CSI-RS resources for reporting, instead of completely changing to a different BWP (e.g., the second active BWP 320). Although Figure 3A illustrates the first active BWP 310 and the second active BWP 320 as overlapping in frequency, the scope of this invention is not limited thereto, and the first and second active BWPs may not necessarily overlap in frequency. Furthermore, although four antennas (or panels) 252a, 252b, 252c, and 252d are illustrated, the present disclosure is not limited thereto, and the techniques described herein are applicable to devices with more than four antennas (or panels) (e.g., six, eight, ten, etc.). While deactivating antennas saves UE power, even greater power savings can be achieved if the UE can reduce the resources used to calculate CSI for MIMO layers that are not expected to be received by the UE (e.g., exceeding the maximum number of MIMO layers the UE is configured to receive). Therefore, there is a need for techniques and apparatus to reduce the Channel State Information (CSI) measurements and calculations performed by User Equipment (UE) assigned to receive a reduced number of Multiple-Input Multiple-Output (MIMO) layers. This includes adaptation of CSI measurements for instances of maximum MIMO layers. The present invention provides techniques for reducing the Channel State Information (CSI) measurements and calculations performed by the User Equipment (UE) based on the maximum number of Multiple-Input Multiple-Output (MIMO) layers that the UE is expected to receive. In various forms of this case, the UE may, for example, process a subset of the CSI-RS resources assigned to the UE based on the maximum number of MIMO layers that the UE is expected to receive, in order to generate an associated CSI report. Depending on the specific circumstances of this case, a base station (e.g., a gNB) may configure a UE with one or more CSI reporting configurations that include one or more CSI-RS resources, wherein each CSI-RS resource includes a set of resources (e.g., a set of time and frequency resources), resource settings, and / or a set of ports for the UE to measure when reporting CSI according to the CSI reporting configuration. In the various forms of this case, it is expected that the UE will only process CSI-RS resources (e.g., time and frequency resources in a subset of resources) in the active BWP assigned to the UE. According to the various forms of the content of this case, when the UE receives an indication regarding the expected number of MIMO layers that the UE is expected to receive less than the maximum number of MIMO layers the UE is capable of receiving (e.g., a BWP assignment with a reduced number of maximum MIMO layers), the UE can calculate the CSI based on a subset of the ports of the configured CSI-RS resources. In various forms of this case, when the UE receives an indication that it expects to receive fewer MIMO layers than the maximum number of MIMO layers the UE is capable of receiving (e.g., a BWP assignment with a reduced number of maximum MIMO layers), the UE can calculate the CSI based on a subset of the CSI-RS resources of the configured CSI-RS resource set. According to the various forms of the content of this case, when the UE receives an indication that the UE is expected to receive fewer MIMO layers than the maximum number of MIMO layers the UE is capable of receiving (e.g., BWP assignment with a reduced number of maximum MIMO layers), the UE can calculate CSI based on a subset of the CSI-RS resource set (e.g., when the UE has been configured to report CSI on multiple CSI-RS resource sets). In various embodiments of this case, when the UE receives an indication regarding the maximum number of MIMO layers the UE is expected to receive that is less than its capacity to receive MIMO layers (e.g., a BWP assignment with a reduced number of maximum MIMO layers), the UE can calculate CSI based on any combination of subsets of ports of the CSI-RS resources configured above, subsets of CSI-RS resources, and / or subsets of the CSI-RS resource set. For example, the UE can be configured with a CSI reporting configuration for measuring CSI on a CSI-RS resource set with 4 CSI-RS resources, where each CSI-RS resource includes 8 ports. In this case, if the UE receives an indication regarding the maximum number of MIMO layers the UE is expected to receive that is less than its capacity to receive MIMO layers (e.g., a BWP assignment with a reduced number of maximum MIMO layers), the UE can process only 2 ports of the first CSI-RS resource, or the UE can process only 2 ports of each of all 4 resources. Depending on the specifics of this case, the BS (e.g., gNB) can determine which ports, CSI-RS resources, CSI-RS resource sets, and / or CSI-RS settings the UE reporting CSI is handling based on whether it expects the UE to receive fewer MIMO layers than the maximum number the UE is capable of receiving. In various forms of this case, the UE may, based on the expected number of MIMO layers that the UE is expected to receive less than the maximum number of MIMO layers the UE is capable of receiving, indicate to the BS in the CSI report which ports, CSI-RS resources, CSI-RS resource sets, and / or CSI-RS settings the UE is processing. Depending on the specific circumstances of this case, there may be a defined or configured order of importance for CSI-RS resources, CSI-RS resource sets, ports, and / or CSI-RS settings (e.g., defined or configured by the BS), and the UE may report (e.g., in a CSI report) the number (e.g., 5) of CSI-RS resources, CSI-RS resource sets, ports, and / or CSI-RS settings processed by the UE when calculating CSI. Subsequently, the BS receiving the CSI report (with the indicated number) determines that the UE processed CSI-RS resources, CSI-RS resource sets, ports, and / or CSI-RS settings in a predefined or preconfigured order up to the indicated number (e.g., the fifth) of CSI-RS resources, CSI-RS resource sets, ports, and / or CSI-RS settings to calculate the CSI in the report. In the various forms of this case, which CSI-RS resources the UE processes to calculate CSI depends on the prioritization of the associated CSI reports. According to the various forms of the content of this case, when the UE is triggered to report CSI based on two CSI reporting configurations with equal priority (where each CSI reporting configuration is associated with a different set of resources, each set of resources includes multiple CSI-RS resources, and each CSI-RS resource has multiple ports), the UE can sample across the resources associated with the two CSI reporting configurations (e.g., subsampling). In various forms of this case, when a UE is triggered to report CSI based on two CSI reporting configurations with different priorities (where each CSI reporting configuration is associated with a different resource set, each resource set includes multiple CSI-RS resources, and each CSI-RS resource has multiple ports), the UE can process only the reports with higher priority. Depending on the specific circumstances of this case, the UE may determine the priority of each CSI report configuration based on the priority rules for PUSCH / PUCCH prioritization and conflict (e.g., as described above). In various forms of this case, the prioritization of CSI reporting configurations (e.g., determining the subset of resources to process for CSI reporting when the UE is expected to receive fewer MIMO layers than its maximum MIMO layer reception capability) can be based on temporal behavior, the content of the corresponding CSI report, the serving cell (e.g., primary or secondary cell) corresponding to the CSI report, and an identifier (e.g., reportConfigID) corresponding to the reporting configuration. For example, the UE may receive one configuration for aperiodic CSI (AP-CSI) reporting and another configuration for semi-persistent scheduling CSI (SP-CSI) reporting. In this case, temporal behavior can be used as the prioritization criterion, and therefore AP CSI reports can have a higher priority than SP CSI reports. Furthermore, if the UE is allowed to focus on one type of report, the UE may decide to focus on AP-CSI reports, for example, due to the higher priority. Thus, for example, if the UE is only able to process two ports, the UE may decide to process the two ports for AP-CSI reporting and not the ports for SP-CSI reporting. In this case, the UE may not process all ports for AP-CSI reporting. Alternatively or supplementally, the UE may not follow a subsampling method, such as processing one port from the AP-CSI report configuration and one port from the SP-CSI report configuration. Depending on the specifics of this case, the prioritization of CSI reporting configurations (e.g., for a subset of resources to report CSI on when the UE is expected to receive fewer MIMO layers than its maximum capacity to receive MIMO layers) can be based on one or more prioritization rules different from previously known prioritization rules for PUSCH / PUCCH prioritization and conflicts (e.g., as described above). Therefore, if the used prioritization indicates that two CSI reporting configurations have equal priority (which is not possible under previously known prioritization rules), the UE can process an equal number of ports, CSI-RS resources, CSI-RS resource sets, and / or CSI-RS settings from each of the CSI reporting configurations. In various forms of the present case, in contrast to measuring CSI-RS resources in a single time slot when the UE is in normal mode (e.g., configured to receive the maximum number of MIMO layers equal to the UE's capability), a UE configured to receive fewer than the maximum number of MIMO layers (e.g., in low-power mode and / or assigned to a power-saving BWP) can measure all CSI-RS resources in the CSI report configuration in a scan mode during multiple time slots (e.g., CSI resource timings (e.g., symbols, time slots, or subframes)). Based on the various forms of the content of this case, the above scanning mode can be completed on the port, CSI resources and / or CSI resource set at the CSI resource timing, so that the UE can measure more CSI resources (e.g., ports) in a time period than the UE can measure in a time slot (e.g., ports). For example, a UE can be configured with a CSI reporting configuration to measure CSI on 8 ports (total) when the UE is in normal mode. In this example, the UE can be configured with a scan mode such that each UE measures only two ports during each time period used for CSI measurement. Ports can be measured in order of port number: ports (0,1), (2,3), (4,5), followed by (6,7). The number of ports to be measured in each time slot can change over time; for example, the UE can measure the CSI of ports (0,1,2,3), (4,5), (6,7), (0,1), (2,3), followed by (4,5,6,7). In various forms of the present case, as mentioned above, when the UE is scanning on a port, CSI resources and / or CSI resource set, the UE can calculate the precoding matrix indicator (PMI), rank indicator (RI) and / or channel quality indicator (CQI) based on the maximum number of layers that the UE is expected to receive independently for each CSI report time (e.g., less than the UE's capacity). According to the various forms of the content of this case, as mentioned above, when the UE is scanning on a port, CSI resource and / or CSI resource set, the UE can calculate PMI, RI and / or CQI based on the union of all layers and / or ports included in the scan mode by combining the channel estimates from the CSI report timing in the scan mode. In various forms of this case, the computational complexity of CSI can be reduced by limiting the RI in each CSI report to the maximum number of MIMO layers the UE is configured to receive. That is, the computational complexity of CSI can be reduced by limiting the RI in each CSI report to the maximum number of MIMO layers the UE is expected to receive. Based on the various aspects of this case, CSI measurements performed by a UE configured for carrier aggregation (CA) can be reduced by decreasing the number of measurements in the dormant BWP to match the maximum number of MIMO layers the UE is expected to receive. Therefore, if the number of MIMO layers the UE is expected to receive is reduced for a UE configured for CA (e.g., PCell PDSCH + SCell CSI for a dormant BWP), CSI report calculations can be reduced by configuring the UE with a constraint that the number of layers used for SCell reception cannot exceed the number of layers used for PCell reception. In in-band CA (e.g., carrier aggregation, where the primary cell and at least one secondary cell operate on the same frequency band), the SCell that the UE is configured to monitor can share the same RF resources used to monitor the PCell that the UE is configured to monitor. That is, a UE configured for in-band CA can use the same receive antenna that the UE uses to monitor the PCell to monitor the SCell. According to the various states of this case, a UE configured for in-band CA may not monitor ports that are not monitored in PCell in SCell. In the various forms of this case, a UE configured for in-band CA can time-align the RF activity of the cell as much as possible. For example, the CSI measurement timing of the SCell should be configured as a subset of the PCell measurement timing. Figure 4 is an exemplary isochronous line 400 of a UE configured for in-band CA according to various configurations of this case. As shown, at 410, the UE is configured with an active BWP 412 on the PCell and active BWPs 414 and 416 on two SCells. At 420, the UE is configured with a power-saving BWP 422 on the PCell, wherein the UE is configured to receive fewer than the maximum number of MIMO layers the UE is capable of receiving. As mentioned above, the UE can determine the CSI-RS resources, CSI-RS resource sets, ports, and / or CSI-RS settings for configuring CSI reporting based on the number of MIMO layers the UE is configured to receive, which is less than the maximum number the UE is capable of receiving. When the UE is configured with a power-saving BWP 422 on the PCell, the UE treats the two SCells as dormant BWPs, wherein the UE does not monitor the PDCCH, does not receive the PDSCH, but performs measurements (e.g., CSI) and reports on those measurements (e.g., CSI reporting). As mentioned above, the UE calculates the CSI for the SCell based on the maximum number of MIMO layers the UE is configured to receive for the PCell. Furthermore, the UE measures the SCell at the time aligned with the measurement of the PCell by the UE. The configuration for the UE to treat the SCell as sleep can be in response to explicit signaling and / or can be implied by the UE being configured with a power-saving BWP on the PCell. At 430, the UE is configured with an active BWP 432 on the PCell and active BWPs 434 and 436 on both SCells. Depending on the specific circumstances of this case, the UE can prioritize CSI reporting configurations based on changes in the UE's available CPU. In various forms of this application, the UE can reduce the number of available CPUs based on time slots, subframes, or frames. The UE can reduce the number of available CPUs to a value lower than the value reported in the capability message from the UE to the BS. Depending on the specific details of this case, the UE can reduce the number of CPUs from the nominal value to different values ​​for different BWPs. In various forms of this case, when the UE's available CPUs have changed, the UE can report the new number of available CPUs to the serving BS. The report of the changed number of available CPUs can be included in the CSI report, or it can be a separate report sent by the UE, for example, via PUCCH. Depending on the specifics of this case, the BS (e.g., gNB) can configure the UE to periodically report the number of currently available CPUs, and subsequently the UE can periodically report the number of available CPUs. In various forms of this case, the UE can be configured to report the number of currently available CPUs on a semi-persistent basis via the Media Access Control (MAC) control element (CE). Depending on the specific circumstances of this case, the UE can be triggered to report the number of currently available CPUs (e.g., dynamic reporting of CPUs) via downlink control information (DCI). In the various forms of this case, whenever the available CPUs of the UE change, there may be a minimum timeframe during which the new number of available CPUs is expected to be valid. That is, when a new number of available CPUs is reported, it is expected that the new number is valid within X time slots, subframes, or frames. Figure 5 is a flowchart illustrating an example operation 500 for wireless communication according to certain states of the present invention. Operation 500 can be performed, for example, by a UE (e.g., UE 120a in wireless communication network 100). Operation 500 can be implemented as a software component executed on one or more processors (e.g., controller / processor 280 of Figure 2). Furthermore, the UE's transmission and reception of signals in operation 500 can be implemented, for example, via one or more antennas (e.g., antenna 252 of Figure 2). In some states, the UE's transmission and / or reception of signals can be implemented via a bus interface of one or more processors (e.g., controller / processor 280) for acquiring and / or outputting signals. Operation 500 can be initiated at block 505 by the following operation: the UE receives a first CSI report configuration including one or more first channel status information (CSI) reference signals (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set. At block 510, operation 500 continues to perform the following operation: the UE determines the first subset of resources to report the first CSI on it based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive. Operation 500 continues at block 515 as follows: The UE reports the first CSI to the base station (BS), where the first CSI is based on the determined first subset of resources. Figure 6 is a flowchart illustrating an example operation 600 for wireless communication according to certain states of the present invention. Operation 600 may be performed, for example, by a BS (e.g., BS 110a such as in wireless communication network 100). Operation 600 may be a supplementary operation performed by the BS to operation 500 performed by the UE. Operation 600 may be implemented as a software component executed on and performed by one or more processors (e.g., controller / processor 240 of Figure 2). Furthermore, the transmission and reception of signals by the BS in operation 600 may be implemented, for example, via one or more antennas (e.g., antenna 234 of Figure 2). In some states, the transmission and / or reception of signals by the BS may be implemented via a bus interface of one or more processors (e.g., controller / processor 240) that acquires and / or outputs signals. Operation 600 can be initiated at block 605 by the following operation: the BS sends a first CSI report configuration to the user equipment (UE) including one or more first channel status information (CSI) reference signal (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set. At block 610, operation 600 can continue to perform the following operation: the BS receives a first CSI from the UE, wherein the first CSI is based on a first resource subset. Operation 600 can continue at block 615 as follows: The BS determines the first subset of resources on which the first CSI is based based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the expected UE will receive. Figure 7 is a flowchart illustrating an example operation 700 for wireless communication according to certain states of the present invention. Operation 700 can be performed, for example, by a UE (e.g., UE 120a such as in wireless communication network 100). Operation 700 can be implemented as a software component that executes on and is performed on one or more processors (e.g., controller / processor 280 of Figure 2). Furthermore, the transmission and reception of signals by the UE in operation 700 can be implemented, for example, via one or more antennas (e.g., antenna 252 of Figure 2). In some states, the transmission and / or reception of signals by the UE can be implemented via a bus interface of one or more processors (e.g., controller / processor 280) that acquires and / or outputs signals. Operation 700 can be initiated at block 705 by changing the number of the UE’s first available Channel State Information (CSI) Reference Signal (CSI-RS) Processing Units (CPUs) to the number of the UE’s second available CPUs based on an indication of the maximum number of Multiple-Input Multiple-Output (MIMO) layers that the UE is expected to receive. At block 710, operation 500 continues as follows: The UE sends an indication to the base station (BS) that the UE has changed to the second number of available CPUs. Figure 8 is a flowchart illustrating an example operation 800 for wireless communication according to certain states of the present invention. Operation 800 may be performed, for example, by a BS (e.g., BS 110a such as in wireless communication network 100). Operation 800 may be a supplementary operation performed by the BS to operation 500 performed by the UE. Operation 800 may be implemented as a software component executed on and performed by one or more processors (e.g., controller / processor 240 of Figure 2). Furthermore, the transmission and reception of signals by the BS in operation 800 may be implemented, for example, via one or more antennas (e.g., antenna 234 of Figure 2). In some states, the transmission and / or reception of signals by the BS may be implemented via a bus interface of one or more processors (e.g., controller / processor 240) that acquires and / or outputs signals. Operation 800 can be initiated at block 805 by the following operation: the BS sends an indication to the user equipment (UE) of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive. At block 810, operation 800 can continue to perform the following operation: the BS receives an indication from the UE that the number of processing units (CPUs) of the UE has changed from the number of the UE's first available channel status information (CSI) reference signal (CSI-RS) to the number of the UE's second available CPUs. Figure 9 illustrates a communication device 900, which may include various components (e.g., corresponding to unit plus functional components) configured to perform operations for the techniques disclosed herein (such as those shown in Figure 5). The communication device 900 includes a processing system 902 coupled to a transceiver 908. The transceiver 908 is configured to transmit and receive signals for the communication device 900 via an antenna 910, such as the various signals described herein. The processing system 902 may be configured to perform processing functions for the communication device 900, including processing signals received and / or to be transmitted by the communication device 900. Processing system 902 includes processor 904 coupled to computer-readable media / memory 912 via bus 906. In some configurations, computer-readable media / memory 912 is configured to store instructions (e.g., computer-executable code) that, when executed by processor 904, cause processor 904 or communication device 900 to perform the operations shown in FIG. 5 or other operations for performing the various techniques discussed herein for reducing channel state information (CSI) measurements and calculations performed by user equipment (UE) assigned to receive a reduced number of maximum multiple-input multiple-output (MIMO) layers. In some embodiments, the computer-readable media / memory 912 stores: code 914 for receiving a first CSI report configuration including one or more first channel status information (CSI) reference signals (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set; code 916 for determining a first subset of resources to report the first CSI on based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and code 918 for reporting the first CSI to the base station (BS), wherein the first CSI is based on the determined first subset of resources. In some embodiments, the processor 904 has circuitry configured to implement the code stored in the computer-readable media / memory 912. The processor 904 includes: circuitry 920 for receiving a first CSI report configuration including one or more first channel status information (CSI) reference signals (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set; circuitry 924 for determining a first subset of resources to report the first CSI on based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and circuitry 926 for reporting the first CSI to a base station (BS), wherein the first CSI is based on the determined first subset of resources. Figure 10 illustrates a communication device 1000, which may include various components (e.g., corresponding to unit plus functional components) configured to perform operations for the techniques disclosed herein (such as those shown in Figure 6). The communication device 1000 includes a processing system 1002 coupled to a transceiver 1008. The transceiver 1008 is configured to transmit and receive signals for the communication device 1000 via an antenna 1010, such as the various signals described herein. The processing system 1002 may be configured to perform processing functions for the communication device 1000, including processing signals received and / or to be transmitted by the communication device 1000. Processing system 1002 includes processor 1004 coupled to computer-readable media / memory 1012 via bus 1006. In some cases, computer-readable media / memory 1012 is configured to store instructions (e.g., computer-executable code) that, when executed by processor 1004, cause processor 1004 or communication device 1000 to perform the operations shown in FIG. 6 or other operations for performing various techniques discussed herein for reducing channel state information (CSI) measurements and calculations performed by user equipment (UEs) assigned to receive a reduced number of multiple-input multiple-output (MIMO) layers. In some embodiments, the computer-readable media / memory 1012 stores: code 1014 for sending a first CSI report configuration to a user equipment (UE) including one or more first channel status information (CSI) reference signals (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set; code 1016 for receiving a first CSI from the UE, wherein the first CSI is based on a first resource subset; and code 1018 for determining the first resource subset on which the first CSI is based based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive. In some embodiments, the processor 1004 has circuitry configured to implement the code stored in the computer-readable media / memory 1012. The processor 1004 includes: circuitry 1020 for sending a first CSI report configuration to a user equipment (UE) including one or more first channel state information (CSI) reference signal (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set; circuitry 1024 for receiving a first CSI from the UE, wherein the first CSI is based on a first resource subset; and circuitry 1026 for determining the first resource subset on which the first CSI is based based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive. Figure 11 illustrates a communication device 1100, which may include various components (e.g., corresponding to unit plus functional components) configured to perform operations for the techniques disclosed herein, such as those shown in Figure 7. The communication device 1100 includes a processing system 1102 coupled to a transceiver 1108. The transceiver 1108 is configured to transmit and receive signals for the communication device 1100 via an antenna 1110, such as the various signals described herein. The processing system 1102 may be configured to perform processing functions for the communication device 1100, including processing signals received and / or to be transmitted by the communication device 1100. Processing system 1102 includes processor 1104 coupled to computer-readable media / memory 1112 via bus 1106. In some cases, computer-readable media / memory 1112 is configured to store instructions (e.g., computer-executable code) that, when executed by processor 1104, cause processor 1104 or communication device 1100 to perform the operations shown in FIG7 or other operations for performing the various techniques discussed herein for reducing channel state information (CSI) measurements and calculations performed by user equipment (UE) assigned to receive a reduced number of maximum multiple-input multiple-output (MIMO) layers. In some configurations, the computer-readable media / memory 1112 stores: code 1114 for changing the number of first available channel state information (CSI) reference signal (CSI-RS) processing units (CPUs) of the UE to a second available CPU number of the UE based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and code 1116 for sending an indication to the base station (BS) that the UE has changed to the second available CPU number. In some configurations, the processor 1104 has circuitry configured to implement the code stored in the computer-readable media / memory 1112. The processor 1104 includes: circuitry 1120 for changing the number of first available channel state information (CSI) reference signal (CSI-RS) processing units (CPUs) of the UE to a second available CPU number of the UE based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and circuitry 1124 for sending an indication to the base station (BS) that the UE has changed to the second available CPU number. Figure 12 illustrates a communication device 1200, which may include various components (e.g., corresponding to unit-plus-function components) configured to perform operations for the techniques disclosed herein, such as those shown in Figure 8. The communication device 1200 includes a processing system 1202 coupled to a transceiver 1208. The transceiver 1208 is configured to transmit and receive signals for the communication device 1200 via an antenna 1210, such as the various signals described herein. The processing system 1202 may be configured to perform processing functions for the communication device 1200, including processing signals received and / or to be transmitted by the communication device 1200. Processing system 1202 includes processor 1204 coupled to computer-readable media / memory 1212 via bus 1206. In some embodiments, computer-readable media / memory 1212 is configured to store instructions (e.g., computer-executable code) that, when executed by processor 1204, cause processor 1204 or communication device 1200 to perform the operations shown in FIG8 or other operations for performing various techniques discussed herein for reducing the number of Channel State Information (CSI) measurements and calculations performed by user equipment (UE) assigned to receive a reduced number of Multiple-Input Multiple-Output (MIMO) layers. In some embodiments, computer-readable media / memory 1212 stores: code 1214 for sending an indication to the user equipment (UE) of the maximum number of MIMO layers the UE is expected to receive; and code 1216 for receiving from the UE an indication that the UE has changed from a first available Channel State Information (CSI) Reference Signal (CSI-RS) processing unit (CPU) number to a second available CPU number. In some configurations, processor 1204 has circuitry configured to implement code stored in computer-readable media / memory 1212. Processor 1204 includes: circuitry 1220 for sending an indication to a user equipment (UE) of the maximum number of multiple-input multiple-output (MIMO) layers the UE is expected to receive; and circuitry 1224 for receiving from the UE an indication that the number of first available channel state information (CSI) reference signals (CSI-RS) processing units (CPUs) of the UE has changed to a second available CPU number of the UE. Example Embodiments Example 1: A method for wireless communication performed by a user equipment (UE), comprising: receiving a first CSI report configuration including one or more first channel state information (CSI) reference signal (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set; determining a first resource subset on which to report the first CSI based on an indication of a maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and reporting the first CSI to a base station (BS), wherein the first CSI is based on the determined first resource subset. Example 2: According to the method of Example 1, the first resource subset includes at least one of the following: a subset of the first port set of the first CSI-RS resources in the first CSI report configuration; a subset of the first resource set of the first CSI-RS resources in the first CSI report configuration; or a subset of the one or more first CSI-RS resources in the first CSI report configuration, wherein the first CSI report configuration includes a plurality of first CSI-RS resources. Example 3: According to the method of Example 1 or 2, the indication of the maximum number of MIMO layers includes the assignment of the active bandwidth portion (BWP) for the UE. Example 4: The method according to any one of Examples 1-3, wherein reporting the first CSI includes: reporting to the BS the first subset of resources on which the first CSI is based. Example 5: The method according to any one of Examples 1-4 also includes calculating the sum of the following: the number of ports in the first resource subset, the number of resources in the first resource set in the first resource subset, and the number of the one or more first CSI-RS resources in the first resource subset, wherein reporting the first CSI includes: reporting the sum to the BS. Example 6: The method according to any one of Examples 1-5 further includes: receiving a second CSI reporting configuration including one or more second CSI-RS resources, wherein each second CSI-RS resource includes a second resource set and a second port set; obtaining a first trigger for reporting the first CSI according to the first CSI reporting configuration; obtaining a second trigger for reporting the second CSI according to the second CSI reporting configuration; and determining to report the first CSI and the second CSI based on a first priority order of the first CSI reporting configuration being equal to a second priority order of the second CSI reporting configuration, wherein the second CSI is based on a second resource subset. Example 7: According to the method of Example 6, the second resource subset includes at least one of the following: a subset of the second port set; a subset of the second resource set; or a subset of the second CSI-RS resources. Example 8: According to the method of Example 6 or 7, the first priority order is based on the temporal behavior of the first CSI, the content of the first CSI, the first service cell corresponding to the first CSI, and the first identifier (ID) corresponding to the first CSI report configuration; and the second priority order is based on the temporal behavior of the second CSI, the content of the second CSI, the second service cell corresponding to the second CSI, and the second identifier (ID) corresponding to the second CSI report configuration. Example 9: The method according to any one of Examples 1-8 further includes: receiving a second CSI reporting configuration including one or more second CSI reference signal (CSI-RS) resources, wherein each second CSI-RS resource includes a second resource set and a second port set; obtaining a trigger for reporting the first CSI according to the first CSI reporting configuration and reporting the second CSI according to the second CSI reporting configuration; and deciding to report the first CSI and discard the second CSI based on a first priority order of the first CSI reporting configuration being higher than a second priority order of the second CSI reporting configuration. Example 10: According to the method of Example 9, the first priority order is based on the temporal behavior of the first CSI, the content of the first CSI, the first service cell corresponding to the first CSI, and the first identifier (ID) corresponding to the first CSI report configuration; and the second priority order is based on the temporal behavior of the second CSI, the content of the second CSI, the second service cell corresponding to the second CSI, and the second identifier (ID) corresponding to the second CSI report configuration. Example 11: The method according to any one of Examples 1-10 further includes: receiving a second CSI reporting configuration including one or more second CSI reference signal (CSI-RS) resources, wherein each second CSI-RS resource includes a second resource set and a second port set; obtaining a trigger for reporting the first CSI according to the first CSI reporting configuration and reporting the second CSI according to the second CSI reporting configuration; and determining the first resource subset based on a first priority order of the first CSI reporting configuration being higher than a second priority order of the second CSI reporting configuration. Example 12: The method according to any one of Examples 1-11 further includes: receiving a second CSI reporting configuration including one or more second CSI reference signal (CSI-RS) resources, wherein each second CSI-RS resource includes a second resource set and a second port set; obtaining a first trigger for reporting the first CSI according to the first CSI reporting configuration; obtaining a second trigger for reporting the second CSI according to the second CSI reporting configuration; and determining to report the first CSI and the second CSI based on a first priority order of the first CSI reporting configuration being equal to a second priority order of the second CSI reporting configuration, wherein the first resource subset is also based on the first priority order being equal to the second priority order, and the method further includes: determining a second resource subset on which the second CSI is to be reported based on the indication of the maximum number of MIMO layers that the UE is expected to receive; and reporting the second CSI to the BS, wherein the second CSI is based on the second resource subset. Example 13: According to the method of Example 12, the second resource subset includes at least one of the following: a subset of the second port set of the second CSI-RS resources in the second CSI report configuration; a subset of the second resource set of the second CSI-RS resources in the second CSI report configuration; or a subset of the second CSI-RS resources in the second CSI report configuration, wherein the second CSI report configuration includes a plurality of second CSI-RS resources. Example 14: The method according to any one of Examples 1-13 also includes: determining the first resource subset based on the scanning pattern of the one or more first CSI-RS resources on multiple time slots. Example 15: According to the method of Example 14, the reporting of the first CSI includes: reporting a precoding matrix indicator (PMI), a rank indicator (RI), and a channel quality indicator (CQI) determined based on a combination of channel estimates from CSI resource timing in the scanning mode. Example 16: The method according to any one of Examples 1-15 also includes: determining the first CSI while limiting the rank indicator (RI) of the first CSI to the maximum number of MIMO layers that the UE is expected to receive. Example 17: The method according to any one of Examples 1-16, wherein the maximum number of MIMO layers that the UE is expected to receive is for the primary cell, and the method also includes: measuring a second CSI for a secondary cell operating in the same frequency band as the primary cell based on the first resource subset. Example 18: The method according to any one of Examples 1-17, wherein the maximum number of MIMO layers that the UE is expected to receive is for the primary cell, and the method also includes: measuring a second CSI for a secondary cell operating in the same frequency band as the primary cell at a time corresponding to the first resource subset. Example 19: A method for wireless communication performed by a user equipment (UE), comprising: changing the number of first available channel state information (CSI) reference signal (CSI-RS) processing units (CPUs) of the UE to a second available CPU number of the UE based on an indication of a maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and sending an indication to a base station (BS) that the UE has changed to the second available CPU number. Example 20: According to the method of Example 19, the indication of the maximum number of MIMO layers includes the assignment of the active bandwidth portion (BWP) for the UE. Example 21: According to the method of Example 19 or 20, the change to the second available CPU number includes: a change based on time slots, subframes, or frames. Example 22: The method according to any one of Examples 19-21, wherein sending the indication that the UE has changed to the second number of available CPUs includes: sending the indication to the BS in a CSI report. Example 23: The method according to any one of Examples 19-22, wherein sending the indication that the UE has changed to the second number of available CPUs includes sending the indication via the Entity Uplink Control Channel (PUCCH). Example 24: The method according to any one of Examples 19-23, wherein the indication that the UE has changed to the second number of available CPUs is sent periodically. Example 25: The method according to any one of Examples 19-24 also includes: receiving a Media Access Control (MAC) element (CE) requesting the UE to report the current number of available CPUs, wherein sending the indication that the UE has changed to the second number of available CPUs is in response to receiving the MAC CE. Example 26: The method according to any one of Examples 19-25 also includes: receiving downlink control information (DCI) requesting the UE to report the current number of available CPUs, wherein sending the indication that the UE has changed to the second number of available CPUs is in response to receiving the DCI. Example 27: A method for wireless communication performed by a base station (BS), comprising: sending a first CSI report configuration to a user equipment (UE) including one or more first channel state information (CSI) reference signal (CSI-RS) resources, wherein each first CSI-RS resource includes a first resource set; receiving the first CSI from the UE, wherein the first CSI is based on a first resource subset; and determining the first resource subset on which the first CSI is based based on an indication of a maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive. Example 28: According to the method of Example 27, the first resource subset includes at least one of the following: a subset of the first port set of the first CSI-RS resources in the first CSI report configuration; a subset of the first resource set of the first CSI-RS resources in the first CSI report configuration; or a subset of the one or more first CSI-RS resources in the first CSI report configuration, wherein the first CSI report configuration includes a plurality of first CSI-RS resources. Example 29: According to the method of Example 27 or 28, the indication of the maximum number of MIMO layers includes the assignment of the BS to the UE's active bandwidth portion (BWP). Example 30: The method according to any one of Examples 27-29, wherein receiving the first CSI includes: receiving a report of the first resource subset on which the first CSI is based. Example 31: The method according to any one of Examples 27-30, wherein receiving the first CSI includes receiving the sum of the following: the number of ports in the first resource subset, the number of resources in the first resource set in the first resource subset, and the number of the first CSI-RS resources in the first resource subset, and wherein the determination of the first resource subset is based on the sum. Example 32: The method according to any one of Examples 27-31 also includes: sending a second CSI report configuration to the UE including one or more second CSI reference signal (CSI-RS) resources, wherein each second CSI-RS resource includes a second resource set and a second port set; receiving a second CSI from the UE, wherein the second CSI is based on a second resource subset; and determining the second resource subset on which the second CSI is based based on an indication of the maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive. Example 33: According to the method of Example 32, the second resource subset includes at least one of the following: a subset of the second port set; a subset of the second resource set; or a subset of the second CSI-RS resources. Example 34: The method according to any one of Examples 27-33, wherein the determination of the first resource subset is based on the scanning mode of the first CSI-RS resource of the UE in multiple time slots. Example 35: According to the method of Example 34, the first CSI includes a precoding matrix indicator (PMI), a rank indicator (RI), and a channel quality indicator (CQI) determined based on a combination of channel estimates from CSI resource timing in the scanning mode. Example 36: The method according to any one of Examples 27-35, wherein the first CSI is based on the rank indicator (RI) of the CSI, which is limited to the maximum number of MIMO layers that the UE is expected to receive. Example 37: According to any one of Examples 27-36, the maximum number of MIMO layers that the UE is expected to receive is for the primary cell, and the method also includes: receiving CSI from the UE for a secondary cell operating in the same frequency band as the primary cell based on the first resource subset. Example 38: The method according to any one of Examples 27-37, wherein the maximum number of MIMO layers that the UE is expected to receive is for the primary cell, and the method also includes: receiving from the UE CSI for a secondary cell operating in the same frequency band as the primary cell at a time corresponding to the first resource subset. Example 39: A method for wireless communication performed by a base station (BS), comprising: sending an indication to a user equipment (UE) of a maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and receiving from the UE an indication that the UE has changed from a first available channel state information (CSI) reference signal (CSI-RS) processing unit (CPU) number to a second available CPU number. Example 40: According to the method of Example 39, the indication of the maximum number of MIMO layers includes the assignment of the BS to the UE's active bandwidth portion (BWP). Example 41: According to the method of Example 39 or 40, the indication from the UE also indicates that the UE is changing to the second number of available CPUs based on the time slot, subframe, or frame. Example 42: The method according to any one of Examples 39-41, wherein receiving the indication that the UE has changed to the second number of available CPUs includes: receiving the indication from the UE in a CSI report. Example 43: The method according to any one of Examples 39-42, wherein receiving the indication that the UE has changed to the second number of available CPUs includes: receiving the indication from the UE via the Physical Uplink Control Channel (PUCCH). Example 44: The method according to any one of Examples 39-43, wherein receiving the indication that the UE has changed to the second number of available CPUs includes: periodically receiving the indication. Example 45: The method according to any one of Examples 39-44 also includes: sending a request to the UE to report the current number of available CPUs in a Media Access Control (MAC) element (CE), wherein the UE responds to the MAC CE to send an indication that the UE has changed to the second number of available CPUs. Example 46: The method according to any one of Examples 39-45 also includes: sending downlink control information (DCI) requesting the UE to report the current number of available CPUs, wherein the UE responds to the DCI to send an indication that the UE has changed to the second number of available CPUs. Example 47: The method according to any one of Examples 1-18, wherein each first CSI-RS resource also includes a first port set. Example 48: The method according to any one of Examples 27-38, wherein each first CSI-RS resource also includes a first port set. Example 49: An apparatus for wireless communication includes a memory and at least one processor coupled to the memory, the memory and the at least one processor being configurable or configured to perform any of the methods according to Examples 1-48. Example 50: An apparatus for wireless communication, comprising a unit for performing any of the methods according to Examples 1-48. Example 51: A computer-readable medium having instructions stored thereon, which, when executed by a processing system, cause the processing system to perform any of the methods according to Examples 1-48. The techniques described in this article can be used in various wireless communication technologies, such as NR (e.g., 5G NR), 3GPP Long Term Evolution (LTE), Improved LTE (LTE-A), Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC FDMA), Time Division Synchronous Code Division Multiple Access (TD-SCDMA), and other networks. The terms "network" and "system" are often used interchangeably. CDMA networks can implement radio technologies such as Universal Terrestrial Radio Access (UTRA), cdma2000, etc. UTRA includes Wideband CDMA (WCDMA) and other variations of CDMA. cdma2000 encompasses the IS-2000, IS-95, and IS-856 standards. TDMA networks can implement radio technologies such as Global System for Mobile Communications (GSM). OFDMA networks can implement radio technologies such as NR (e.g., 5G RA), Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, and Flash-OFDMA. UTRA and E-UTRA are part of the Universal Mobile Telecommunications System (UMTS). LTE and LTE-A are versions of UMTS using E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents from an organization called the 3rd Generation Partnership Project (3GPP). cdma2000 and UMB are described in documents from an organization called the 3rd Generation Partnership Project 2 (3GPP2). NR is an emerging wireless communication technology currently being deployed. The techniques described herein can be used in the wireless network and radio technologies mentioned above, as well as other wireless network and radio technologies. For clarity, although this document may use terms commonly associated with 3G, 4G, and / or 5G wireless technologies to describe various aspects, the aspects of this document can be applied to other generation-based communication systems. In 3GPP, the term "cell" can represent the coverage area of ​​a Node B (NB) and / or the NB subsystem serving that coverage area, depending on the context in which the term is used. In NR systems, the term "cell" is interchangeable with BS, Next Generation Node B (gNB or gNodeB), Access Point (AP), Distributed Unit (DU), and Transmit / Receive Point (TRP). A BS can provide communication coverage for macrocells, picocells, femtocells, and / or other types of cells. A macrocell can cover a relatively large geographic area (e.g., a radius of several kilometers) and can allow unrestricted access by UEs with service subscriptions. A picocell can cover a relatively small geographic area and can allow unrestricted access by UEs with service subscriptions. A femtocell can cover a relatively small geographic area (e.g., a residential area) and can allow restricted access by UEs associated with that femtocell (e.g., UEs in a Closed Subscriber Group (CSG), UEs for users in a residential area, etc.). A BS used for macrocells can be called a macro BS. A BS used for picocells can be called a pico BS. BS used for femtocellular cells can be called femtocellular BS or home BS. A UE can also be referred to as a mobile station, terminal, access terminal, user unit, station, customer premises equipment (CPE), cellular phone, smartphone, personal digital assistant (PDA), wireless modem, wireless communication equipment, handheld device, laptop, wireless phone, wireless loop (WLL) station, tablet computer, camera, gaming device, laptop, smart computer, ultrabook, appliance, medical device or medical apparatus, biometric sensor / device, wearable device (e.g., smartwatch, smart clothing, smart glasses, smart wristband, smart jewelry (e.g., smart ring, smart bracelet, etc.)), entertainment device (e.g., music device, video device, satellite radio unit, etc.), vehicle component or sensor, smart instrument / sensor, industrial manufacturing equipment, GPS device, or any other suitable device configured to communicate via wireless or wired media. Some UEs can be considered machine-type communication (MTC) devices or evolved MTC (eMTC) devices. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc., which can communicate with the BS, another device (e.g., a remote device), or some other entity. Wireless nodes can provide connectivity to or from a network (e.g., a wide area network such as the Internet or cellular networks) via wired or wireless communication links. Some UEs can be considered Internet of Things (IoT) devices, which can be narrowband IoT (NB-IoT) devices. Some wireless networks (e.g., LTE) utilize Orthogonal Frequency Division Multiplexing (OFDM) on the downlink and Single Carrier Frequency Division Multiplexing (SC-FDM) on the uplink. OFDM and SC-FDM divide the system bandwidth into multiple (K) orthogonal subcarriers, which are often referred to as tones, frequency bands, etc. Data can be used to modulate each subcarrier. Typically, modulation symbols are transmitted using OFDM in the frequency domain and SC-FDM in the time domain. The spacing between adjacent subcarriers can be fixed, and the total number of subcarriers (K) can depend on the system bandwidth. For example, the subcarrier spacing can be 15 kHz, and the minimum resource allocation (called a "resource block" (RB)) can be 12 subcarriers (or 180 kHz). Therefore, for system bandwidths of 1.25, 2.5, 5, 10, or 20 MHz, the nominal Fast Fourier Transform (FFT) size can be 128, 256, 512, 1024, or 2048, respectively. The system bandwidth can also be divided into subbands. For example, a subband can cover 1.08 MHz (i.e., 6 RBs), and for system bandwidths of 1.25, 2.5, 5, 10, or 20 MHz, there can be 1, 2, 4, 8, or 16 subbands, respectively. In LTE, the Basic Transmission Time Interval (TTI) or packet duration is a 1 ms subframe. NR can utilize OFDM with CP on both uplink and downlink, and can include support for half-duplex operation using TDD. In NR, the subframe is still 1 ms, but the basic TTI is called a time slot. The subframe contains a variable number of time slots (e.g., 1, 2, 4, 8, 16... time slots) depending on the subcarrier spacing. The NR RB is 12 consecutive frequency subcarriers. NR can support a basic subcarrier spacing of 15 kHz, and other subcarrier spacings can be defined relative to the basic subcarrier spacing, such as 30 kHz, 60 kHz, 120 kHz, 240 kHz, etc. Symbol and time slot lengths scale with the subcarrier spacing. The CP length also depends on the subcarrier spacing. Beamforming can be supported, and beam direction can be dynamically configured. MIMO transmission with precoding can also be supported. In some instances, the MIMO configuration in the DL can support up to 8 transmit antennas, with up to 8 streams transmitted in the multilayer DL and up to 2 streams per UE. In some instances, multi-layer transport with up to two streams per UE can be supported. Aggregation of multiple cells with up to eight service cells can be supported. In some instances, access to the air interface can be scheduled. A scheduling entity (e.g., a BS) allocates resources for communication among some or all devices and apparatuses within its service area or cell. The scheduling entity can be responsible for scheduling, allocating, reconfiguring, and releasing resources for one or more dependent entities. That is, for scheduled communication, the dependent entity utilizes the resources allocated by the scheduling entity. A base station is not the only entity that can be used as a scheduling entity. In some instances, a UE can be used as a scheduling entity and can schedule resources for one or more dependent entities (e.g., one or more other UEs), and other UEs can utilize the resources scheduled by that UE for radio communication. In some instances, a UE can be used as a scheduling entity in peer-to-peer (P2P) networks and / or mesh networks. In mesh network instances, in addition to communicating with scheduling entities, UEs can also communicate directly with each other. In some instances, two or more dependent entities (e.g., UEs) can communicate with each other using sidelink signals. Real-world applications of such sidelink communication can include public safety, proximity services, UE-to-network relay, vehicle-to-vehicle (V2V) communication, Internet of Things (IoE) communication, IoT communication, mission-critical mesh networks, and / or various other suitable applications. Typically, a sidelink signal can represent a signal transmitted from one dependent entity (e.g., UE1) to another dependent entity (e.g., UE2) without requiring relaying of the communication via a scheduling entity (e.g., UE or BS), even if the scheduling entity may be used for scheduling and / or control purposes. In some instances, licensed spectrum can be used to transmit sidelink signals (unlike wireless local area networks that typically use unlicensed spectrum). The methods disclosed herein include one or more steps or actions for implementing the methods. These method steps and / or actions may be interchanged with each other without departing from the scope of the request. In other words, unless a specific order of steps or actions is specified, the order and / or use of a particular step and / or action may be modified without departing from the scope of the request. As used herein, the term "decision" encompasses a wide variety of actions. For example, "decision" can include calculation, operation, processing, deduction, investigation, examination (e.g., examining a table, database, or other data structure), ascertainment, identification, and so on. Furthermore, "decision" can include receiving (e.g., receiving information), accessing (e.g., accessing data in memory), and so on. Additionally, "decision" can include parsing, selecting, choosing, creating, and so on. Furthermore, the term "or" is intended to mean an inclusive "or," not an exclusive "or." That is, unless otherwise specified or clearly understood from the context, the phrase "X adopts A or B" is intended to mean any of the natural inclusive substitutions. That is, for example, any of the following instances satisfy the phrase "X adopts A or B": X adopts A; X adopts B; or X adopts both A and B. As used herein, unless specifically stated otherwise, references to elements in the singular form are not intended to mean "one and only one," but rather "one or more." For example, unless otherwise specified or clearly understood from the context to be for the singular form, the articles "a" and "an" as used in this case and the appended claims should generally be interpreted as meaning "one or more." Unless otherwise expressly stated, the term "some" means one or more. Phrases referring to "at least one of" a list of items represent any combination of those items, including a single member. As an example, "at least one of a, b, or c" is intended to encompass a, b, c, ab, ac, bc, and abc, as well as any combination of multiples of the same element (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, and ccc, or any other ordering of a, b, and c). As used herein (including in the request item), the term "and / or," when used in a list having two or more items, means that any one of the listed items can be used alone, or any combination of two or more of the listed items can be used. For example, if a composition is described as containing components A, B, and / or C, then the composition can contain: A only; B only; C only; a combination of A and B; a combination of A and C; a combination of B and C; or a combination of A, B, and C. The foregoing description is provided to enable anyone skilled in the art to implement the various embodiments described herein. Various modifications to these embodiments will be apparent to those skilled in the art, and the overall principles defined herein can be applied to other embodiments. Therefore, the claims are not intended to be limited to the embodiments shown herein, but are given the full scope consistent with the wording of the claims, wherein, unless specifically stated otherwise, references to singular elements are not intended to mean "one and only one," but rather "one or more." Unless otherwise expressly stated, the term "some" refers to one or more. All structural and functional equivalents of the elements throughout the various embodiments described herein are expressly incorporated herein by reference, and are intended to be included by the claims, of structural and functional equivalents that are known or to be known to those skilled in the art. Furthermore, nothing disclosed herein is intended to be offered to the public, whether or not such disclosure is expressly stated in the claims. No claim element is to be interpreted in accordance with the provisions of patent law unless the element is explicitly stated using the phrase "unit for..." or, in the case of a method claim, the element is stated using the phrase "step for...". The various operations of the methods described above can be performed by any suitable unit capable of performing the corresponding function. These units may include various hardware and / or software components and / or modules, including but not limited to: circuits, application-specific integrated circuits (ASICs), or processors. Typically, in the presence of operations as shown in the figures, those operations may have corresponding paired units plus functional components with similar numbering. The various illustrative logic blocks, modules, and circuits described in connection with this case can be implemented or executed using a general-purpose processor, digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA) or other programmable logic device (PLD), individual gate or transistor logic, individual hardware components, or any combination thereof, designed to perform the functions described herein. The general-purpose processor may be a microprocessor, but alternatively, the processor may be any commercially available processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration. If implemented in hardware, the instance hardware configuration may include a processing system in a wireless node. The processing system can be implemented using a bus architecture. Depending on the specific application and overall design constraints of the processing system, the bus may include any number of interconnecting buses and bridges. The bus can connect various circuits, including processors, machine-readable media, and bus interfaces. In addition, the bus interface can also be used to connect network interface cards (NICs) to the processing system via the bus. The NIC can be used to implement signal processing functions at the PHY layer. In the case of user terminal 120 (see Figure 1), a user interface (e.g., keypad, display, mouse, joystick, etc.) can also be connected to the bus. The bus can also connect various other circuits, such as timing sources, peripherals, voltage regulators, power management circuits, etc., which are well known in the art to which this invention pertains and will therefore not be described further. The processor can be implemented using one or more general-purpose and / or special-purpose processors. Examples include microprocessors, microcontrollers, DSP processors, and other circuits capable of executing software. Those skilled in the art to which this invention pertains will recognize how to optimally implement the functions described for the processing system, depending on the specific application and the overall design constraints imposed on the system as a whole. If implemented in software, such functionality can be stored as one or more instructions or codes on or transmitted via a computer-readable medium. Whether referred to as software, firmware, middleware, microcode, hardware description language, or other terms, software should be broadly interpreted to mean instructions, data, or any combination thereof. Computer-readable media includes both computer storage media and communication media, with communication media encompassing any media that facilitates the transfer of computer programs from one location to another. The processor can be responsible for managing buses and general-purpose processing, including executing software modules stored on machine-readable storage media. The computer-readable storage media can be coupled to the processor so that the processor can read information from and write information to the storage media. Alternatively, the storage media can be an integral part of the processor. For example, machine-readable media can include transmission lines, data-modulated carrier waves, and / or separate computer-readable storage media containing instructions stored thereon, all accessible to the processor via a bus interface. Alternatively or additionally, machine-readable media, or any portion thereof, may be integrated into the processor; for example, this could be cache memory and / or a general-purpose temporary storage stack. Examples of machine-readable storage media include RAM (Random Access Memory), flash memory, ROM (Read-Only Memory), PROM (Programmable Read-Only Memory), EPROM (Erasable Programmable Read-Only Memory), EEPROM (Electronic Erasable Programmable Read-Only Memory), temporary storage, magnetic disks, optical disks, hard drives, or any other suitable storage media, or any combination thereof. Machine-readable media may be embodied in computer program products. Software modules can include a single instruction or many instructions, and can be distributed across several different code segments, within different programs, and across multiple storage media. Computer-readable media can include multiple software modules. Software modules include instructions that, when executed by a device such as a processor, cause the processing system to perform various functions. Software modules can include send modules and receive modules. Each software module can reside in a single storage device or be distributed across multiple storage devices. For example, when a triggering event occurs, a software module can be loaded from a hard drive into RAM. During the execution of a software module, the processor can load some of the instructions into cache memory to increase access speed. Subsequently, one or more cache memory lines can be loaded into a general-purpose temporary register heap for execution by the processor. It will be understood that when the functionality of a software module is referred to below, this functionality is implemented by the processor when executing the instructions from that software module. Furthermore, any connection is appropriately referred to as computer-readable media. For example, if software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technology (e.g., infrared (IR), radio, and microwave), then coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technology (e.g., infrared, radio, and microwave) is included in the definition of media. As used herein, disk and disc include compressed optical disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk, and Blu-ray® disc, wherein disk typically copies data magnetically, while disc uses laser to optically copy data. Therefore, in some cases, computer-readable media may include non-transitory computer-readable media (e.g., tangible media). Furthermore, in other cases, computer-readable media may include transient computer-readable media (e.g., signals). Combinations of the above should also be included within the scope of computer-readable media. Therefore, certain forms may include a computer program product for performing the operations provided herein. For example, such a computer program product may include a computer-readable medium having instructions stored (and / or encoded thereon) thereon, which can be executed by one or more processors to perform the operations described herein, such as instructions for performing the operations described herein and shown in Figures 5, 6, 7 and / or 8. Furthermore, it should be understood that modules and / or other suitable units for performing the methods and techniques described herein can be downloaded and / or otherwise obtained by the user terminal and / or base station, where applicable. For example, such a device can be coupled to a server to facilitate the transmission of units for performing the methods described herein. Alternatively, the various methods described herein can be provided via storage units (e.g., RAM, ROM, physical storage media such as CDs or floppy disks, etc.) so that the user terminal and / or base station can access the various methods when the storage unit is coupled to or provided to the device. Additionally, any other suitable techniques for providing the methods and techniques described herein to the device can be used. It should be understood that the requested items are not limited to the precise configurations and components shown above. Various modifications, alterations, and variations may be made to the arrangement, operation, and details of the methods and apparatus described above without departing from the scope of the requested items. 100: Wireless Communication Network; 102a: Macro Cell; 102b: Macro Cell; 102c: Macro Cell; 102x: Chip Cell; 102y: Femtocell; 102z: Femtocell; 110a: BS110b: BS110c: BS110r: Relay Station; 110x: BS110y: BS110z: BS112: CSI; 120: UE; 120a: UE120r: ​​UE120x: UE120y: UE122: CSI; 130: Network Controller; 212: Data Source; 220: Processor; 230: Transmit (TX) Multiple-Input Multiple-Output (MIMO) Processor 232a: Modulator (MOD) 232t: Modulator (MOD) 234a: Antenna 234t: Antenna 236: MIMO Detector 238: Receive Processor 239: Data Slot 240: Controller / Processor 241: CSI 242: Memory 244: Scheduler 252a: Antenna 252b: Antenna 252c: Antenna 252d: Antenna 252r: Antenna 254: Demodulator 254a: Demodulator 254r: Demodulator 256: MIMO Detector 258: Receive Processor 260: Data Slot 262: Data Source 264: Transmit Processor 266: TX MIMO Processor 280: Controller / Processor 281: Adaptation CSI 282: Memory 300: Isochronous Line 310: First Active BWP 320: Second Active BWP 330: Program 335: Program 400: Isochronous Line 410: Program 412, 414, 416: Active BWP 420: Program 422: Power Saving BWP 430: Program 432, 434, 436: Active BWP 500: Operation; 505, 510, 515: Block; 600: Operation 605, 610, 615: Block; 700: Operation 705, 710: Block; 800: Operation 805, 810: Block; 900: Communication equipment; 902: Processing system; 904: Processor; 906: Bus; 908: Transceiver; 910: Antenna; 912: Computer-readable media / memory; 914, 916, 918: Code 9 20, 924, 926: Circuit; 1000: Communication Equipment; 1002: Processing System; 1004: Processor; 1006: Bus; 1008: Transceiver; 1010: Antenna; 1012: Brain-Readable Media / Memory; 1014, 1016, 1018: Code; 1020, 1024, 1026: Circuit; 1100: Communication Equipment; 1102: Processing System; 1104: Processor; 1106: Bus 1108: Transceiver; 1110: Antenna; 1112: Computer-readable media / memory; 1114, 1116: Codes; 1120, 1124: Circuitry; 1200: Communication equipment; 1202: Processing system; 1204: Processor; 1206: Bus; 1208: Transceiver; 1210: Antenna; 1212: Computer-readable media / memory; 1214, 1216: Codes; 1220, 1224: Circuitry. To gain a more detailed understanding of the aforementioned features of this case, a more specific description can be made by referring to various embodiments (briefly outlined above), some of which are shown in the accompanying drawings. However, it should be noted that the drawings only illustrate certain typical embodiments of this case and are therefore not intended to limit its scope, as the description may allow for other equally valid embodiments. Figure 1 is a block diagram conceptually illustrating some aspects of an example telecommunications system according to the content of this case. Figure 2 is a block diagram conceptually illustrating the design of an example base station (BS) and user equipment (UE) according to certain aspects of the content of this case. Figure 3A is an exemplary transmission isochrone of various forms according to the content of this case. Figure 3B illustrates the startup configuration of an example UE antenna (or panel) according to the various states described in this case. Figure 4 is an exemplary isochron of a UE configured for in-band carrier aggregation according to various states of the present case. Figure 5 is a flowchart illustrating an example operation for wireless communication by a UE according to certain aspects of the present case. Figure 6 is a flowchart illustrating an example operation of wireless communication by a BS in certain forms according to the content of this case. Figure 7 is a flowchart illustrating an example operation for wireless communication by a UE according to certain aspects of the present case. Figure 8 is a flowchart illustrating an example operation of wireless communication by a BS in certain forms according to the content of this case. Figure 9 illustrates various communication devices according to the content of this case, which may include various components configured to perform the operations shown in Figure 5. Figure 10 illustrates various communication devices according to the contents of this case, which may include various components configured to perform the operations shown herein in Figure 6. Figure 11 illustrates various communication devices according to the content of this case, which may include various components configured to perform the operations shown in Figure 7. Figure 12 illustrates various communication devices according to the contents of this case, which may include various components configured to perform the operations shown herein in Figure 8. To aid understanding, the same component symbols have been used where possible to designate common elements that are consistent with the accompanying drawings. It is intended that elements shown in one specification can be usefully used in other specifications without requiring specific description. 500: Operation 505: Square 510: Square 515: Square

Claims

1. A method for wireless communication performed by a user equipment (UE), comprising the steps of: changing the number of a first available channel state information (CSI) reference signal (CSI-RS) processing units (CPUs) of the UE to a second available CPU number of the UE based on an indication of a maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and sending an indication to a network entity that the UE has changed to the second available CPU number.

2. According to the method of request item 1, wherein the indication of the maximum number of MIMO layers includes an assignment of an active bandwidth portion (BWP) for the UE.

3. According to the method of request item 1, wherein changing the number of the second available CPUs includes the following steps: making a change based on a time slot, subframe, or frame.

4. According to the method of request item 1, sending the indication that the UE has changed to the second number of available CPUs includes the following steps: sending the indication to the network entity in a CSI report.

5. According to the method of request item 1, sending the indication that the UE has changed to the second number of available CPUs includes the following steps: sending the indication via an entity uplink control channel (PUCCH).

6. According to the method of request item 1, wherein the indication that the UE has changed to the second number of available CPUs is sent periodically.

7. The method according to request item 1 also includes the following steps: receiving a Media Access Control (MAC) control element (CE) requesting the UE to report a current number of available CPUs, wherein sending an indication that the UE has changed to the second number of available CPUs is in response to receiving the MAC CE.

8. The method according to request item 1 also includes the following steps: receiving downlink control information (DCI) requesting the UE to report a current number of available CPUs, wherein sending an indication that the UE has changed to the second number of available CPUs is in response to receiving the DCI.

9. A method for wireless communication performed by a network entity, comprising the steps of: sending an indication to a user equipment (UE) of a maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and receiving from the UE an indication that the UE has changed from a first number of available channel state information (CSI) reference signals (CSI-RS) processing units (CPUs) to a second number of available CPUs.

10. The method according to request item 9, wherein the indication of the maximum number of MIMO layers includes an assignment of an active bandwidth portion (BWP) of the network entity to the UE.

11. The method according to request item 9, wherein the indication from the UE further indicates that the UE is changing to the second number of available CPUs on the basis of a time slot, subframe, or frame.

12. The method according to request item 9, wherein receiving the indication that the UE has changed from the first number of available CPUs to the second number of available CPUs includes the following steps: receiving the indication from the UE in a CSI report.

13. The method according to request item 9, wherein receiving the indication that the UE has changed from the first number of available CPUs to the second number of available CPUs includes the following steps: receiving the indication via a physical uplink control channel (PUCCH) from the UE.

14. The method according to request item 9, wherein receiving the indication that the UE has changed to the second number of available CPUs includes the following steps: periodically receiving the indication.

15. The method according to request item 9 also includes the following steps: sending a media access control (MAC) control element (CE) requesting the UE to report a current number of available CPUs, wherein the indication that the UE has changed from the first number of available CPUs to the second number of available CPUs is in response to the MAC CE.

16. The method according to request item 9 also includes the following steps: sending a request to the UE to report a current available CPU number (DCI), wherein the indication that the UE has changed from the first available CPU number to the second available CPU number is in response to the DCI.

17. A user equipment (UE) configured for wireless communication, comprising: A memory containing computer-executable instructions; and a processor configured to execute the computer-executable instructions and cause the UE to: change the number of a first available channel state information (CSI) reference signal (CSI-RS) processing unit (CPU) of the UE to a second available CPU of the UE based on an indication of a maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and send an indication to a network entity that the UE has changed to the second available CPU number.

18. The UE according to request item 17, wherein the indication of the maximum number of MIMO layers includes an assignment of an active bandwidth portion (BWP) for the UE.

19. The UE according to request item 17, wherein the processor is configured to change the UE to the second available CPU number including the processor being configured to change the UE on a time slot, subframe, or frame basis.

20. The UE according to request item 17, wherein the processor is configured to cause the UE to send an indication that the UE has changed to the second number of available CPUs, including the processor being configured to cause the UE to send the indication to the network entity in a CSI report.

21. The UE according to request item 17, wherein the processor is configured to enable the UE to send the indication that the UE has changed to the second number of available CPUs, includes the processor being configured to enable the UE to send the indication via an Entity Uplink Control Channel (PUCCH).

22. The UE according to request item 17, wherein the processor is configured to cause the UE to send the indication regarding the UE having changed to the second number of available CPUs, includes the processor being configured to cause the UE to send the indication periodically.

23. The UE according to request item 17, wherein the processor is configured to execute the computer-executable instructions and further cause the UE to: receive a Media Access Control (MAC) control element (CE) requesting the UE to report a current number of available CPUs, wherein the processor is configured to cause the UE to send an indication that the UE has changed to the second number of available CPUs, including the processor being configured to cause the UE to send the indication in response to receiving the MAC CE.

24. The UE according to request item 17, wherein the processor is configured to execute the computer-executable instructions and further cause the UE to perform the following operations: receive a request for the UE to report a current number of available CPUs (DCI), wherein the processor is configured to cause the UE to send an indication that the UE has changed to the second number of available CPUs, including the processor being configured to cause the UE to send the indication in response to receiving the DCI.

25. A network entity configured for wireless communication, comprising: A memory containing computer-executable instructions; and a processor configured to execute the computer-executable instructions and cause the network entity to perform the following operations: sending an indication to a user equipment (UE) of a maximum number of multiple-input multiple-output (MIMO) layers that the UE is expected to receive; and receiving from the UE an indication that the UE has changed from a first available channel state information (CSI) reference signal (CSI-RS) processing unit (CPU) number to a second available CPU number.

26. The network entity according to request item 25, wherein the indication of the maximum number of MIMO layers includes an assignment by the network entity to an active bandwidth portion (BWP) of the UE.

27. The network entity according to request item 25, wherein the processor is configured to receive the instruction from the UE, including the processor being configured to receive a further instruction indicating that the UE is changing to the second number of available CPUs on a time slot, subframe, or frame basis.

28. The network entity according to request item 25, wherein the processor is configured to receive an indication that the UE has changed from the first number of available CPUs to the second number of available CPUs, including the processor being configured to receive the indication via at least one of: a CSI report from the UE; or an entity uplink control channel (PUCCH) from the UE.

29. The network entity according to request item 25, wherein the processor is configured to receive the indication that the UE has changed to the second number of available CPUs, including the processor being configured to periodically receive the indication.

30. The network entity according to request item 25, wherein the processor is configured to execute the computer-executable instructions and further cause the network entity to perform the following operations: sending a Media Access Control (MAC) Control Element (CE) or Downlink Control Information (DCI) requesting the UE to report a current number of available CPUs, wherein the processor is configured to cause the network entity to receive an indication that the UE has changed from the first number of available CPUs to the second number of available CPUs, including the processor being configured to receive the indication in response to the MAC CE or the DCI.

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