Multiple channel state feedback reports for MU-MIMO scheduling assistance

Abstract

Methods are presented relating to wireless communication systems and selecting a group of user equipment (UE) devices to multiplex for multi-user multiple input and multiple output (MU-MIMO) communication. A base station transmits a channel state report configuration to a first UE of a plurality of UEs, the channel state report configuration indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources. The BS receives a channel state report from the first UE, the channel state report including interference prediction information based on the set of one or more interference measurement resources and the precoding information. The BS uses the channel state report to determine a group configuration for the plurality of UEs. Other features are also claimed and described.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of U.S. Patent Application No. 16 / 862,543, filed April 29, 2020, which is hereby incorporated by reference in its entirety as if fully set forth below and for all applicable purposes. Technical Field

[0003] The following technology relates generally to wireless communication systems, and more particularly to multi-user multiple-input multiple-output (MU-MIMO) scheduling. Certain embodiments may implement and provide techniques that allow a base station to efficiently obtain interference measurement information and / or channel variation information from user equipment devices for use in MU-MIMO scheduling.

[0004] introduction

[0005] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcast, and the like. These systems may be capable of supporting communication with multiple users by sharing available system resources (e.g., time, frequency, and power). A wireless multiple-access communication system may include several base stations (BSs), each of which simultaneously supports communication for multiple communication devices (e.g., user equipment (UE)).

[0006] To meet the growing demand for extended mobile broadband connectivity, wireless communication technology is evolving from Long Term Evolution (LTE) technology to the next generation New Radio (NR) technology, which may be referred to as the fifth generation (5G). For example, NR is designed to provide lower latency, higher bandwidth or higher throughput, and higher reliability compared to LTE. NR is designed to operate over a wide range of frequency bands, for example, from low-frequency bands below about 1 gigahertz (GHz) and mid-frequency bands from about 1 GHz to about 6 GHz, to high-frequency bands such as millimeter wave (mmWave) bands. NR is also designed to operate across different spectrum types, from licensed spectrum to unlicensed and shared spectrum. As use cases and diverse deployment scenarios continue to expand in wireless communications, improvements in decoding technology may also bring benefits.

[0007] In multi-user multiple-input multiple-output (MU-MIMO) communications, a device may simultaneously employ multiple antenna ports to transmit and / or receive signals in multiple spatial directions. When a base station (BS) seeks to communicate with multiple UEs in parallel using MU-MIMO (e.g., simultaneously using the same frequency allocation), it may decide which UEs to spatially multiplex for synchronous communications. For example, UEs that are spatially close together may experience greater mutual interference than UEs that are spatially far apart, so the BS may group UEs that are farther away for parallel or synchronous communications. Deciding which UEs to multiplex in a group may involve obtaining various interference measurements from the UEs, but current methods of scheduling groups of UEs for parallel communications may not adequately account for mutual interference between specific UEs that may be grouped together.

[0008] A brief overview of some examples

[0009] The following summarizes some aspects of the present disclosure to provide a basic understanding of the technology discussed. This summary is not an exhaustive overview of all contemplated features of the present disclosure, and is neither intended to identify key or critical elements of all aspects of the present disclosure, nor is it intended to define the scope of any or all aspects of the present disclosure. Its sole purpose is to provide some concepts of one or more aspects of the present disclosure in summary form as a prelude to the more detailed description that will be given later.

[0010] Some aspects of the present disclosure implement and provide mechanisms and techniques that enable a BS to obtain interference measurement information from a UE for parallel scheduling using MU-MIMO. The BS can provide precoding information to each UE to allow the UE to use a common pilot (i.e., a non-zero power channel state information reference signal (NZP-CSI-RS) for channel response) to reconstruct an interference stream to account for potential interference from other UEs being considered for parallel scheduling, without relying on multiple resource-intensive NZP-CSI-RS for interference estimation. For example, the BS can transmit a pilot without precoding on the NZP-CSI-RS for the UE to estimate the channel response, and configure the UE with a list of potential precodings (e.g., a precoding matrix index or a codebook index) that the BS can use for several other UEs. The UE can estimate the interference for each precoding in the list based on the estimated channel response and the corresponding precoding, rather than having the BS transmit NZP-CSI-RS with different precoding combinations. Accordingly, the BS may transmit a list of NZP-CSI-RS resource indices and corresponding precoding information to each UE, and each UE may feed back a CSF report indicating the selected NZP-CSI-RS resource configuration and / or corresponding precoding that may generate the least amount of interference at the specific UE.

[0011] For example, in one aspect of the present disclosure, a wireless communication method includes: transmitting a channel state report configuration from a base station (BS) to a first UE among a plurality of user equipments (UEs), the channel state report configuration indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources. The method further includes: receiving, by the BS, a channel state report from the first UE, the channel state report including interference prediction information based on the set of one or more interference measurement resources and the precoding information. The method further includes: determining, by the BS, a group configuration for the plurality of UEs based at least in part on the received channel state report.

[0012] In an additional aspect of the present disclosure, a wireless communication method includes: receiving, by a UE, a channel state report configuration from a base station (BS), the channel state report configuration indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources. The method further includes: transmitting, by the UE, a channel state report to the BS, the channel state report including interference prediction information based on the set of one or more interference measurement resources and the precoding information.

[0013] In an additional aspect of the present disclosure, a base station (BS) includes a transceiver configured to transmit a channel state report configuration to a first UE among a plurality of UEs, the channel state report configuration indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources. The transceiver is further configured to receive a channel state report from the first UE, the channel state report including interference prediction information based on the set of one or more interference measurement resources and the precoding information. The BS also includes a processor configured to determine a group configuration for the plurality of UEs based at least in part on the received channel state report.

[0014] In an additional aspect of the present disclosure, a UE includes a processor and a transceiver. The transceiver is configured to receive a channel state report configuration from a base station (BS), the channel state report configuration indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources. The transceiver is further configured to transmit a channel state report to the BS, the channel state report including interference prediction information based on the set of one or more interference measurement resources and the precoding information.

[0015] After studying the following description of specific exemplary embodiments in conjunction with the accompanying drawings, other aspects, features and embodiments will be apparent to those of ordinary skill in the art. Although each feature may be discussed below with respect to certain embodiments and drawings, all embodiments may include one or more of the advantageous features discussed herein. In other words, although one or more embodiments may be discussed as having certain advantageous features, one or more such features may also be used according to the various embodiments discussed herein. In a similar manner, although exemplary embodiments may be discussed below as device, system or method embodiments, it should be appreciated that such exemplary embodiments may be implemented in various devices, systems, and methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1

[0014] Illustrated is a wireless communication network in accordance with some aspects of the present disclosure.

[0018] Figure 2

[0014] Illustrated is a wireless communication network in accordance with some aspects of the present disclosure.

[0019] Figure 3 Illustrated are exemplary non-zero power channel state information reference signal (NZP-CSI-RS) resource allocation and transmission schemes for multi-user multiple input and multiple output (MU-MIMO) in accordance with some aspects of the present disclosure.

[0020] Figure 4 is a block diagram of an exemplary base station (BS) according to some aspects of the present disclosure.

[0021] Figure 5 is a block diagram of an example user equipment (UE) according to some aspects of the present disclosure.

[0022] Figure 6 is an exemplary sequence diagram illustrating a communication sequence according to some aspects of the present disclosure.

[0023] Figure 7

[0046] Illustrated are exemplary NZP-CSI-RS resource allocation and transmission schemes for MU-MIMO according to some aspects of the present disclosure.

[0024] Figure 8 is an exemplary sequence diagram illustrating a communication sequence according to some aspects of the present disclosure.

[0025] Figure 9 is a flow diagram of wireless communications according to some aspects of the present disclosure.

[0026] Figure 10 is a flow diagram of wireless communications according to some aspects of the present disclosure.

[0027] Figure 11is a flow diagram of wireless communications according to some aspects of the present disclosure.

[0028] Figure 12 is a flow diagram of wireless communications according to some aspects of the present disclosure.

[0029] Detailed description

[0030] The detailed description set forth below in conjunction with the accompanying drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. This detailed description includes specific details in order to provide a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form to avoid obscuring such concepts.

[0031] The present disclosure generally relates to wireless communication systems (also referred to as wireless communication networks). In various embodiments, various technologies and equipment may be used for wireless communication networks, such as code division multiple access (CDMA) networks, time division multiple access (TDMA) networks, frequency division multiple access (FDMA) networks, orthogonal FDMA (OFDMA) networks, single carrier FDMA (SC-FDMA) networks, LTE networks, global system for mobile communications (GSM) networks, fifth generation (5G) or new radio (NR) networks, and other communication networks. As described herein, the terms "network" and "system" may be used interchangeably.

[0032] OFDMA networks can implement radio technologies such as Evolved UTRA (E-UTRA), Institute of Electrical and Electronics Engineers (IEEE) 802.11, IEEE 802.16, IEEE 802.20, flash-OFDM, etc. UTRA, E-UTRA, and GSM are part of the Universal Mobile Telecommunications System (UMTS). Specifically, Long Term Evolution (LTE) is a version of UMTS that uses E-UTRA. UTRA, E-UTRA, GSM, UMTS, and LTE are described in documents provided by an organization called the "3rd Generation Partnership Project" (3GPP), while cdma2000 is described in documents from an organization called the "3rd Generation Partnership Project 2" (3GPP2). These various radio technologies and standards are either known or under development. For example, the 3rd Generation Partnership Project (3GPP) is a collaboration between a group of telecommunications associations that aims to define globally applicable third generation (3G) mobile phone specifications. 3GPP Long Term Evolution (LTE) is a 3GPP project aimed at improving the UMTS mobile phone standard. 3GPP may define specifications for next generation mobile networks, mobile systems, and mobile devices. This disclosure focuses on the evolution of wireless technologies from LTE, 4G, 5G, NR, and beyond, with shared access to wireless spectrum between networks using a collection of new and different radio access technologies or radio air interfaces.

[0033] Specifically, 5G networks envision diverse deployments, diverse spectrum, and diverse services and devices that can be implemented using a unified air interface based on OFDM. To achieve these goals, in addition to developing new radio technologies for 5G NR networks, further enhancements to LTE and LTE-A are also being considered. 5G NR will be able to scale to: (1) serve networks with ultra-high density (e.g., approximately 1M nodes / km) 2 (1) providing coverage for the Massive Internet of Things (IoT) with ultra-low complexity (e.g., on the order of tens of bits / second), ultra-low energy (e.g., on the order of 10+ years of battery life), and deep coverage capable of reaching challenging locations; (2) providing coverage including mission-critical control with strong security (to protect sensitive personal, financial, or confidential information), ultra-high reliability (e.g., on the order of 99.9999% reliability), ultra-low latency (e.g., on the order of 1 ms), and for users with a wide range of mobility or lack thereof; and (3) providing coverage with enhanced mobile broadband, including very high capacity (e.g., on the order of 10 Tbps / km 2 ), extreme data rates (e.g., multi-Gbps rates, 100+Mbps user experience rates), and deep cognition with advanced discovery and optimization.

[0034] 5G NR communication systems can be implemented to use optimized OFDM-based waveforms with scalable parameter sets and transmission time intervals (TTIs). Additional features may also include a common, flexible framework for efficiently multiplexing services and features using dynamic, low-latency time division duplex (TDD) / frequency division duplex (FDD) designs; and the use of advanced wireless technologies such as massive multiple-input multiple-output (MIMO), robust millimeter wave (mmWave) transmission, advanced channel coding, and device-centric mobility. The scalability of parameter design in 5G NR (and the scaling of subcarrier spacing) can efficiently address the operation of diverse services across diverse spectrums and diverse deployments. For example, in various outdoor and macro coverage deployments implemented with less than 3 GHz FDD / TDD, subcarrier spacing can occur at 15 kHz, such as on bandwidths (BWs) of 5, 10, 20 MHz, etc. For other various outdoor and small cell coverage deployments with TDD greater than 3 GHz, subcarrier spacing can occur at 30 kHz on 80 / 100 MHz BWs. For various other indoor broadband implementations, using TDD on the unlicensed portion of the 5 GHz band, subcarrier spacing can occur at 60 kHz over 160 MHz BW. Finally, for various deployments transmitting using the mmWave component with TDD at 28 GHz, subcarrier spacing can occur at 120 kHz over 500 MHz BW.

[0035] The scalable parameter design of 5G NR facilitates scalable TTI to meet diverse latency and quality of service (QoS) requirements. For example, shorter TTIs can be used for low latency and high reliability, while longer TTIs can be used for higher spectral efficiency. Efficient multiplexing of long and short TTIs allows transmissions to start on symbol boundaries. 5G NR also contemplates a self-contained integrated subframe design with UL / downlink scheduling information, data, and acknowledgments in the same subframe. The self-contained integrated subframe supports communications in unlicensed or contention-based shared spectrum, and supports adaptive UL / downlink that can be flexibly configured on a per-cell basis to dynamically switch between UL and downlink to meet current traffic needs.

[0036] Various other aspects and features of the present disclosure are further described below. It should be apparent that the teachings herein can be embodied in a variety of forms, and any specific structure, function, or both disclosed herein are representative and non-limiting. Based on the teachings herein, it will be appreciated by those of ordinary skill in the art that the aspects disclosed herein can be implemented independently of any other aspects and that two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement a device or practice a method. In addition, other structures, functionality, or structure and functionality that supplement or differ from one or more aspects set forth herein can be used to implement such a device or practice such a method. For example, the method can be implemented as a part of a system, device, apparatus, and / or as an instruction stored on a computer-readable medium for execution on a processor or computer. Not only that, an aspect can include at least one element of a claim.

[0037] The base station (BS) in 5G NR is able to use multiple antenna ports to communicate with multiple user equipment (UE) devices in parallel, a process known as multi-user multiple input multiple output (MU-MIMO). An antenna port can refer to a physical antenna element or a virtual or logical antenna port formed by multiple physical antenna elements with specific amplitude and / or phase weights per antenna element. For example, the base station (BS) can group UEs that are spatially distant from each other and multiplex the UE group for parallel or simultaneous transmission. Existing methods used by the BS to schedule UE groups for parallel communication may not take into account the mutual interference between specific UEs that can be grouped together. For example, the BS can configure resources for non-zero power channel state information reference signal (NZP-CSI-RS) transmission for each UE. The BS can configure several NZP-CSI-RS resources in a resource set for each UE. The NZP-CSI-RS can be one of the following two types: (1) NZP-CSI-RS for channel response estimation or (2) NZP-CSI-RS for interference estimation. The NZP-CSI-RS used for channel response estimation is a pilot (e.g., a reference signal) transmitted by a transmit antenna (or antenna port) before precoding (i.e., without precoding) and can be used by the UE to measure the downlink channel (e.g., radio signal propagation channel) associated with that antenna or antenna port. If there are multiple resources, each resource may have its own pilot. The NZP-CSI-RS used for interference estimation is a precoded pilot, where the precoding is configured in the same manner as when transmitting data to another UE (e.g., an interfering UE), so that the measuring UE can estimate the interference from the other UE.

[0038] Each UE may perform channel estimation based on the received NZP-CSI-RS for channel response estimation, perform interference measurement based on the received NZP-CSI-RS for interference estimation, create a channel state feedback (CSF) report based on the channel response estimate and / or interference estimate, and transmit the CSF report to the BS. In some examples, the CSF report may include a channel state information reference signal resource indication (CRI), which is a channel state information reference signal (CSI-RS) resource index that indicates the CSI-RS preferred by the UE based on the channel response estimate and / or interference estimate of the UE. Each CRI may identify an NZP-CSI-RS resource. In some examples, there may be a one-to-one mapping between the CRI and the antenna port at the BS. In other words, each CRI may identify the resource used by the corresponding antenna port to transmit the pilot. In some other examples, the CRI may identify the resource location used by the antenna port group to transmit the pilot. For example, when the number of antenna ports at the BS exceeds a limit (which may be a predefined value (e.g., 2, 4, 8, 12, 16, 24, 32, or as may be defined in, for example, a 3GPP standard), the BS may group the antenna ports for CSI-RS transmission. For example, the BS may have approximately 256 antenna ports, while the standard may allow a maximum of 32 ports. Therefore, the BS may form, for example, 32 antenna port groups, with 8 antenna ports in each group. Thus, each CRI may correspond to one of the 32 antenna port groups. The CSF report may also include channel quality information (CQI), rank indicator (RI), and precoding matrix indicator (PMI) for the preferred CSI-RS resource indicated by the CRI. In some other examples, the CSF report may include RI, PMI, and / or CQI for each configured CSI-RS resource.

[0039] Although the UE can determine the potential interference from other UEs in the MU-MIMO group, the BS may need some knowledge of the downlink channel for each UE served by the BS (e.g., via channel state information feedback or channel reciprocity), the MU-MIMO pre-scheduling configuration (e.g., the candidate UE group for MU-MIMO), and the potential precoding to be used for each candidate UE. The BS can then transmit the appropriate NZP-CSI-RS corresponding to each precoding. For example, for a group containing four UEs (UE 0, UE 1, UE 2, and UE 3), the BS can transmit NZP-CSI-RS with various precoding options (e.g., NZP-CSI-RS #0-NZP-CSI-RS #3) to each UE, which the BS can potentially use to communicate with each of the other UEs in the group. For example, the BS may transmit a pilot without precoding on NZP-CSI-RS #0 for UE0 to estimate the channel response, transmit a pilot with potential precoding for UE1 on NZP-CSI-RS #1 for UE0 to estimate interference from UE1, transmit a pilot with potential precoding for UE2 on NZP-CSI-RS #2 for UE0 to estimate interference from UE2, and transmit a pilot with potential precoding for UE3 on NZP-CSI-RS #3 for UE0 to estimate interference from UE3. The BS may repeat a similar process for UE1, UE2, and UE3 to estimate the channel response and the interference from each of the other UEs in the group. As can be seen, the number of precoding combinations for NZP-CSI-RS #0, #1, #2, and #3 may be large, and thus the system overhead in terms of resource utilization, measurement processing, and / or time may be significant, making link adaptation difficult.

[0040] Furthermore, existing channel state feedback (CSF) reporting mechanisms may not allow for optimal outer loop link adaptation (OLLA). Link adaptation generally refers to a wireless device selecting appropriate transmission parameters (e.g., modulation and coding scheme (MCS)) for a given channel condition at a given moment. Specifically, OLLA aims to adjust the radio link to maintain the block error rate (BLER) of a transmission below a target threshold. For example, a base station (BS) may select an MCS for a first transmission to a UE based on channel conditions at a first moment to achieve a certain performance (e.g., a BLER target). If the channel conditions remain similar, the BS may use the same MCS for a second transmission and achieve a similar BLER that meets the BLER target for the second transmission. If the channel conditions degrade at a third moment and the BS continues to use the same MCS for the third transmission, the BS may detect an increase in the BLER that fails to meet the BLER target. The BS may perform OLLA to detect the change in BLER and select a lower MCS level (e.g., an offset from the previous MCS) for subsequent transmissions so that the target BLER can be maintained. In some examples, the UE may also report a CQI to the BS (based on the received transmission), and the BS may determine changes in the channel based on the reported CQI and adjust the MCS used for communications with the UE based on the channel changes.

[0041] Accordingly, OLLA can be useful when dealing with mismatches in physical downlink shared channel (PDSCH) allocation relative to CSF ​​allocation. OLLA can also be useful when the device is subject to a noise profile that is different from the noise profile previously indicated in the channel state information for interference measurement (CSI-IM) signal (e.g., due to changes in the channel over time). In addition, OLLA can compensate for CSF reporting delays. For example, there may be a lag between the time when the CSF is generated at the device or UE and the time when the CSF report is sent to the BS, during which the channel may have changed. However, OLLA can only track the CQI (or MCS) offset using the latest rank index (RI) and / or precoding matrix indicator (PMI) value returned in the CSF report, which limits the ability of OLLA to determine an accurate CQI (or MCS) offset estimate when the signal is subject to jitter relative to its RI and / or PMI. As a result, the maximum throughput for high MCS values ​​may also be limited. Furthermore, OLLA may be limited to tuning or adapting the MCS (given the RI and / or PMI) to achieve a desired BLER, and may be limited in its ability to tune the RI and PMI to adapt to variations in the channel.

[0042] The present disclosure provides a technique for a BS to obtain interference measurement information from a UE for parallel scheduling using MU-MIMO technology without transmitting a large number of precoded CSI-RS to the UE. Instead of transmitting NZP-CSI-RS for interference from possible precoded interference streams or layers, the BS can instead provide precoding information to each UE to allow the UE to use a common pilot (i.e., NZP-CSI-RS for channel response) to reconstruct the interference stream to account for potential interference from other UEs being considered for parallel scheduling. Parallel scheduling or parallel communication can refer to the BS simultaneously receiving UL signals (e.g., UL data streams) from each UE in a MU-MIMO UE group (via different spatial layers or spatial directions) or simultaneously transmitting DL signals (e.g., DL data streams) to each UE in a MU-MIMO UE group (via different spatial layers or spatial directions). NZP-CSI-RS can be used for both channel estimation and interference measurement. For example, continuing the example of UEs 0-3 above, the BS can transmit a pilot without precoding on NZP-CSI-RS #0 for UE 0 to estimate the channel response, and configure UE 0 with a list of potential precodings (e.g., precoding matrix indices or codebook indices) that the BS can use for UE 1, UE 2, and / or UE 3. UE 0 can estimate the interference for each precoding in the list based on the estimated channel response and the corresponding precoding, rather than having the BS transmit NZP-CSI-RS with different precoding combinations. Accordingly, the BS can transmit a list of NZP-CSI-RS resource indices and the corresponding precoding information, and each UE can feed back a CSF report indicating the selected NZP-CSI-RS resource configuration and / or corresponding precoding that is likely to generate the least amount of interference at the UE.

[0043] For example, according to various aspects of the present disclosure, the BS may transmit a CSF configuration to each connected UE, indicating the NZP-CSI-RS resources and requesting precoding, rank and / or channel quality information from the UE. After the UE returns a CSF including the requested parameters, the BS may then create an extended CSF configuration that includes information about other UEs (i.e., interference sources) that may be grouped with the receiving UE. The extended CSF configuration may include an indication of the following: a list of NZP-CST-RS resources and one or more precoding parameters that may potentially be used with transmissions in the resources indicated by each NZP-CST-RS resource in the list. The NZP-CSI-RS resource list may be in the form of a resource configuration index indicating the NZP-CSI-RS resources. Alternatively, the BS may send the extended configuration without first receiving an initial CSF report from the UE. The BS may then trigger the UE to report CSF information for potential precoding configurations at the BS, or receive a CSF report (in the absence of a trigger) through periodic data transfer.

[0044] In some aspects, the UE may transmit the CSF report via the media access control (MAC) layer. For example, the BS may request the first UE for recommended PMI, CQI, and RI information for each NZP-CSI-RS resource in the NZP-CSI-RS resource list, thereby taking into account the potential interference caused by the desired communication between the BS and the second UE. The BS may request multiple CSF reports based on different potential configurations (e.g., different combinations of UEs). The interference measurement / estimation information determined by the UE to be included in the report may be based on the same NZP-CSI-RS signal used for channel estimation. For example, the UE may perform channel / interference estimation for each NZP-CSI-RS resource precoding combination, select the NZP-CSI-RS resource precoding combination that may cause the least amount of interference to the UE, and feedback the measurement result information and / or selection (e.g., including a CRI indicating the selected NZP-CSI-RS resource) in the CSF report to the BS. The BS may then make scheduling decisions based on the CSF report regarding which UEs to group for parallel communication and the configuration for MU-MIMO (eg, precoding and / or modulation and coding scheme (MCS)) for each UE in the group.

[0045] The present disclosure also provides techniques for improving OLLA by utilizing similar interference prediction-based CSF reporting techniques discussed above. For example, the BS may configure the UE to report expected CQI at certain time intervals within a time period based on the predicted interference. Thus, the BS may receive CQI reports and estimate channel variations during time periods when the BS has no data transmission to the UE. This may allow the BS to prepare for link adaptation when the BS receives data for transmission to the UE. Additionally, OLLA may be improved by augmenting CSF reporting with MCS recommendations per potential rank, rather than reporting the best MCS corresponding to the current rank recommendation (or the best rank estimated by the UE or used by the UE for current communication). For example, the BS may configure an RI list and / or a PMI list for the UE, and the UE may report a recommended MCS for each PMI in the list, each RI in the list, and / or each combination of PMI and RI in the list. The BS may also configure the UE to report a history of CQIs and corresponding RIs and / or PMIs. The historical information may allow the BS to exclude or not include CQIs during jitter periods when performing OLLA.

[0046] Aspects of the present disclosure may provide several benefits. For example, aspects of the present disclosure enable the BS to more efficiently group UEs for MU-MIMO without the need for additional CSI-RS transmission overhead. Aspects of the present disclosure may also improve overall network resource utilization by using a single NZP-CSI-RS for both channel estimation and interference measurement, freeing up resources of the NZP-CSI-RS that would otherwise be used for channel estimation and a different NZP-RS dedicated to interference measurement. Aspects of the present disclosure may also improve OLLA, for example, by alleviating the impact of jitter on CQI determination. Although the present disclosure is described in the context of LTE and / or NR networks, the present disclosure may be applied to any wireless communication technology that implements MU-MIMO. The present disclosure is also applicable to TDD systems or FDD systems. Additionally, CSF and / or CQI reporting based on interference prediction may be used in conjunction with legacy CSF and / or CQI reporting mechanisms based on interference measurement.

[0047] Although various aspects and embodiments are described in this application by way of illustration of some examples, it will be understood by those skilled in the art that additional implementations and use cases may be generated in many different arrangements and scenarios. The innovations described herein may be implemented across many different platform types, devices, systems, shapes, sizes, and packaging arrangements. For example, various embodiments and / or uses may be generated via integrated chip embodiments and other devices based on non-module components (e.g., end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail / shopping devices, medical devices, AI-enabled devices, etc.). Although some examples may or may not be specifically for each use case or application, the wide applicability of the described innovations may occur. The scope of each implementation may range from chip-level or module components to non-module, non-chip-level implementations, and further to aggregated, distributed, or OEM devices or systems incorporating one or more aspects of the described innovations. In some practical environments, the devices incorporating the various aspects and features described may also necessarily include additional components and features for implementing and practicing the claimed and described embodiments. For example, the transmission and reception of wireless signals necessarily include several components for analog and digital purposes (e.g., hardware components including antennas, RF chains, power amplifiers, modulators, buffers, processors, interleavers, adders / summers, etc.). The innovations described herein are intended to be practiced in a wide variety of devices, chip-level components, systems, distributed arrangements, end-user devices, and the like, of various sizes, shapes, and configurations.

[0048] Figure 1 Illustrated is a wireless communication network 100 according to some aspects of the present disclosure. Network 100 may be a 5G network. Network 100 includes several base stations (BSs) 105 (labeled 105a, 105b, 105c, 105d, 105e, and 105f) and other network entities. BSs 105 may be stations that communicate with UEs 115 and may also be referred to as evolved Node Bs (eNBs), next-generation eNBs (gNBs), access points, and the like. Each BS 105 may provide communication coverage for a particular geographic area. In 3GPP, the term "cell" may refer to that particular geographic coverage area of ​​a BS 105 and / or a BS subsystem serving that coverage area, depending on the context in which the term is used.

[0049] BS 105 may provide communication coverage for macro cells or small cells (such as pico cells or femto cells), and / or other types of cells. Macro cells generally cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs that have a service subscription with a network provider. Small cells (such as pico cells) generally cover a relatively small geographic area and may allow unrestricted access by UEs that have a service subscription with a network provider. Small cells (such as femto cells) generally also cover a relatively small geographic area (e.g., a residence) and, in addition to unrestricted access, may also provide restricted access to UEs associated with the femto cell (e.g., UEs in a closed subscriber group (CSG), UEs of users in the residence, etc.). A BS for a macro cell may be referred to as a macro BS. A BS for a small cell may be referred to as a small cell BS, a pico BS, a femto BS, or a home BS. In Figure 1 In the example shown in FIG, BS 105d and 105e may be conventional macro BSs, while BSs 105a-105c may be macro BSs enabled with one of three-dimensional (3D), full-dimensional (FD), or massive MIMO. BSs 105a-105c may utilize their higher-dimensional MIMO capabilities to utilize 3D beamforming in both elevation and azimuth beamforming to increase coverage and capacity. BS 105f may be a small cell BS, which may be a home node or a portable access point. BS 105 may support one or more (e.g., two, three, four, etc.) cells.

[0050] Network 100 may support synchronous or asynchronous operation. For synchronous operation, each BS may have similar frame timing, and transmissions from different BSs may be approximately aligned in time. For asynchronous operation, each BS may have different frame timing, and transmissions from different BSs may not be aligned in time.

[0051] UEs 115 may be dispersed throughout wireless network 100, and each UE 115 may be stationary or mobile. Each UE may take a variety of forms and a range of form factors. UE 115 may also be referred to as a terminal, mobile station, subscriber unit, station, etc. UE 115 may be a cellular phone, personal digital assistant (PDA), wireless modem, wireless communication device, handheld device, tablet computer, laptop computer, cordless phone, wireless local loop (WLL) station, etc. In one aspect, UE 115 may be a device that includes a Universal Integrated Circuit Card (UICC). In another aspect, a UE may be a device that does not include a UICC. In some aspects, a UE 115 that does not include a UICC may also be referred to as an IoT device or an Internet of Everything (IoE) device. UEs 115a-115d are examples of mobile smartphone-type devices that access network 100. UE 115 may also be a machine specifically configured for connected communications, including machine-type communications (MTC), enhanced MTC (eMTC), narrowband IoT (NB-IoT), etc. UEs 115e-115h are examples of various machines configured for communication that access network 100. UEs 115i-115k are examples of vehicles equipped with wireless communication devices configured for communication that access network 100. UE 115 may be able to communicate with any type of BS (whether a macro BS, a small cell, etc.). Figure 1 In the figure, the lightning beam (e.g., communication link) indicates a wireless transmission between the UE 115 and the serving BS 105, a desired transmission between the BSs 105, a backhaul transmission between the BSs, or a sidelink transmission between the UEs 115, where the serving BS 105 is a BS designated to serve the UE 115 on the downlink (DL) and / or uplink (UL).

[0052] In operation, BSs 105a-105c may use 3D beamforming and coordinated spatial techniques (such as coordinated multipoint (CoMP) or multi-connectivity) to serve UEs 115a and 115b. Macro BS 105d may perform backhaul communications with BSs 105a-105c and small cell BS 105f. Macro BS 105d may also transmit multicast services that are subscribed to and received by UEs 115c and 115d. Such multicast services may include mobile television or streaming video, or may include other services for providing community information (such as weather emergencies or warnings, such as Amber Alerts or Gray Alerts).

[0053] The BSs 105 may also communicate with a core network. The core network may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. At least some of the BSs 105 (e.g., which may be examples of gNBs or access node controllers (ANCs)) may interface with the core network via a backhaul link (e.g., NG-C, NG-U, etc.) and may perform radio configuration and scheduling for communications with the UEs 115. In various examples, the BSs 105 may communicate with each other directly or indirectly (e.g., through the core network) over a backhaul link (e.g., X1, X2, etc.), which may be a wired or wireless communication link.

[0054] The network 100 may also support mission-critical communications with ultra-reliable and redundant links for mission-critical devices, such as UE 115e, which may be a drone. The redundant communication links with UE 115e may include links from macro BSs 105d and 105e, as well as a link from small cell BS 105f. Other machine-type devices, such as UE 115f (e.g., a thermometer), UE 115g (e.g., a smart meter), and UE 115h (e.g., a wearable device), may communicate directly with a BS (e.g., small cell BS 105f and macro BS 105e) via the network 100, or in a multi-step configuration by communicating with another user device that relays its information to the network (e.g., UE 115f conveys temperature measurement information to smart meter UE 115g, which is then reported to the network via small cell BS 105f). The network 100 may also provide additional network efficiency through dynamic, low latency TDD / FDD communications, such as V2V, V2X, C-V2X communications between UE 115i, 115j, or 115k and other UEs 115, and / or vehicle-to-infrastructure (V2I) communications between UE 115i, 115j, or 115k and BS 105.

[0055] In some implementations, network 100 utilizes OFDM-based waveforms for communication. OFDM-based systems can divide the system BW into multiple (K) orthogonal subcarriers, which are also commonly referred to as subcarriers, frequency tones, frequency bins, etc. Each subcarrier can be modulated with data. In some examples, the subcarrier spacing between adjacent subcarriers can be fixed, and the total number of subcarriers (K) can depend on the system BW. The system BW can also be divided into subbands. In other examples, the subcarrier spacing and / or the duration of the TTI can be scalable.

[0056] In some aspects, BS 105 may assign or schedule transmission resources (e.g., in the form of time-frequency resource blocks (RBs)) for downlink (DL) and uplink (UL) transmissions in network 100. DL refers to the transmission direction from BS 105 to UE 115, while UL refers to the transmission direction from UE 115 to BS 105. This communication may take the form of radio frames. A radio frame may be divided into a plurality of subframes or time slots, e.g., approximately 10. Each time slot may be further divided into subslots. In FDD mode, simultaneous UL and DL transmissions may occur in different frequency bands. For example, each subframe includes a UL subframe in the UL frequency band and a DL subframe in the DL frequency band. In TDD mode, UL and DL transmissions occur in different time periods using the same frequency band. For example, a subset of subframes in a radio frame (e.g., DL subframes) may be used for DL ​​transmissions, and another subset of subframes in the radio frame (e.g., UL subframes) may be used for UL transmissions.

[0057] DL subframes and UL subframes can be further divided into several regions. For example, each DL or UL subframe may have a predefined region for the transmission of reference signals, control information, and data. Reference signals are predetermined signals that facilitate communication between BS 105 and UE 115. For example, the reference signal may have a specific pilot pattern or structure, wherein the pilot tones may span the operating BW or frequency band, and each pilot tone is positioned at a predefined time and a predefined frequency. For example, BS 105 may transmit a cell-specific reference signal (CRS) and / or a channel state information-reference signal (CSI-RS) to enable UE 115 to estimate the DL channel. Similarly, UE 115 may transmit a sounding reference signal (SRS) to enable BS 105 to estimate the UL channel. Control information may include resource assignments and protocol control. Data may include protocol data and / or operational data. In some aspects, BS 105 and UE 115 may communicate using self-contained subframes. A self-contained subframe may include a portion for DL ​​communication and a portion for UL communication. A self-contained subframe may be DL-centric or UL-centric. A DL-centric subframe may include a duration for DL ​​communication that is longer than a duration for UL communication. A UL-centric subframe may include a duration for UL communication that is longer than a duration for DL ​​communication.

[0058] In some aspects, network 100 may be an NR network deployed on a licensed spectrum. BS 105 may transmit synchronization signals (e.g., including a primary synchronization signal (PSS) and a secondary synchronization signal (SSS)) in network 100 to facilitate synchronization. BS 105 may broadcast system information associated with network 100 (e.g., including a master information block (MIB), residual system information (RMSI), and other system information (OSI)) to facilitate initial network access. In some instances, BS 105 may broadcast the PSS, SSS, and / or MIB in the form of a synchronization signal block (SSB) on a physical broadcast channel (PBCH), and may broadcast the RMSI and / or OSI on a physical downlink shared channel (PDSCH).

[0059] In some aspects, a UE 115 attempting to access the network 100 may perform an initial cell search by detecting the PSS from the BS 105. The PSS may enable synchronization of period timing and may indicate a physical layer identity value. The UE 115 may then receive the SSS. The SSS may enable radio frame synchronization and may provide a cell identity value that may be combined with the physical layer identity value to identify the cell. The PSS and SSS may be located in the center portion of the carrier or at any suitable frequency within the carrier.

[0060] After receiving the PSS and SSS, the UE 115 may receive the MIB. The MIB may include system information for initial network access and scheduling information for RMSI and / or OSI. After decoding the MIB, the UE 115 may receive the RMSI and / or OSI. The RMSI and / or OSI may include radio resource control (RRC) information related to random access channel (RACH) procedures, paging, control resource sets (CORESETs) for physical downlink control channel (PDCCH) monitoring, physical UL control channel (PUCCH), physical UL shared channel (PUSCH), power control, and SRS.

[0061] After obtaining the MIB, RMSI, and / or OSI, the UE 115 may perform a random access procedure to establish a connection with the BS 105. The random access procedure (or RACH procedure) may be a single-step or multi-step process. In some examples, the random access procedure may be a four-step random access procedure. For example, the UE 115 may transmit a random access preamble, and the BS 105 may respond with a random access response. The random access response (RAR) may include a detected random access preamble identifier (ID) corresponding to the random access preamble, timing advance (TA) information, an UL grant, a temporary cell radio network temporary identifier (C-RNTI), and / or a backoff indicator. Upon receiving the random access response, the UE 115 may transmit a connection request to the BS 105, and the BS 105 may respond with a connection response. The connection response may indicate a contention resolution method. In some examples, the random access preamble, RAR, connection request, and connection response may be referred to as message 1 (MSG 1), message 2 (MSG 2), message 3 (MSG 3), and message 4 (MSG 4), respectively. In some examples, the random access procedure may be a two-step random access procedure, in which the UE 115 may transmit a random access preamble and a connection request in a single transmission, and the BS 105 may respond by transmitting a random access response and a connection response in a single transmission.

[0062] After establishing the connection, the UE 115 and the BS 105 can enter a normal operation phase, in which operational data can be exchanged. For example, the BS 105 can schedule the UE 115 for UL and / or DL ​​communications. The BS 105 can transmit an UL and / or DL ​​scheduling grant to the UE 115 via the PDCCH. The scheduling grant can be transmitted in the form of DL control information (DCI). The BS 105 can transmit a DL communication signal (e.g., carrying data) to the UE 115 via the PDSCH based on the DL scheduling grant. The UE 115 can transmit an UL communication signal to the BS 105 via the PUSCH and / or PUCCH based on the UL scheduling grant.

[0063] In some aspects, the network 100 may operate on a system BW or a component carrier (CC) BW. The network 100 may divide the system BW into multiple BWPs (e.g., multiple portions). The BS 105 may dynamically assign the UE 115 to operate on a certain BWP (e.g., a certain portion of the system BW). The assigned BWP may be referred to as an active BWP. The UE 115 may monitor the active BWP for signaling information from the BS 105. The BS 105 may schedule the UE 115 to conduct UL or DL ​​communications in the active BWP. In some aspects, the BS 105 may assign a BWP pair within a CC to the UE 115 for UL and DL communications. For example, the BWP pair may include one BWP for UL communications and one BWP for DL ​​communications.

[0064] In some aspects, the BS 105 may transmit a CSF configuration to multiple connected UEs 115, indicating the NZP-CSI-RS resources and requesting precoding, rank, and / or channel quality information from the UEs 115. After the UEs 115 return a CSF including the requested parameters, the BS 105 may then create an extended CSF configuration that includes information about other UEs 115 (i.e., interferers) that may be grouped with the receiving UE 115. The extended CSF configuration may include a list of NZP-CSI-RS resources and one or more precoding parameters that may be potentially used with transmissions in the resources indicated by each NZP-CSI-RS resource in the list. The NZP-CSI-RS resource list may be in the form of a resource configuration index that indicates the NZP-CSI-RS resources. Alternatively, the BS 105 may send the extended configuration without first receiving an initial CSF report from the UE 115. BS 105 may then trigger UE 115 to report CSF information for potential precoding configurations at BS 105, or receive CSF reports through periodic data transfer (in the absence of a trigger). CSF reports may be transmitted from UE 115 on the MAC layer. For example, BS 105 may request from a first UE recommended PMI, CQI, and RI information for each NZP-CSI-RS resource in a list of NZP-CSI-RS resources, thereby accounting for potential interference caused by communications between BS 105 and a second UE 115. BS 105 may request multiple CSF reports based on different potential configurations (e.g., different combinations of UEs 115). The interference measurement / estimation information performed by UE 115 for inclusion in the report may be based on the same NZP-CSI-RS signal used for channel estimation. For example, the UE 115 may perform channel / interference estimation for each NZP-CSI-RS resource-precoding combination, select the NZP-CSI-RS resource-precoding combination that is likely to produce the least amount of interference to the UE 115, and feed back the measurement information and / or selection (e.g., including a CRI indicating the selected NZP-CSI-RS resource) in a CSF report to the BS 105. The BS 105 may then make scheduling decisions about which UEs 115 to group for parallel communication (e.g., simultaneous communication) and the configuration for MU-MIMO (e.g., precoding and / or modulation and coding scheme (MCS)) for each UE 115 in the group based on the CSF report.

[0065] Figure 2A wireless communication network 200 according to some aspects of the present disclosure is illustrated. Although only one BS 205 (which may be BS 105) and four UEs 215 (which may be UE 115) are illustrated for simplicity, embodiments of the present disclosure can be extended to any number of BSs 205 and UEs 215. BS 205 can communicate with multiple UEs 215 using beams 220. For example, BS 205 can communicate with UE 215a using beam 220a, communicate with UE 215b using beam 220b, communicate with UE 215c using beam 220c, and communicate with UE 215d using beam 220d. When determining how to group (i.e., multiplex) multiple UEs 215 for MU-MIMO parallel communication, spatially close UEs 215 may suffer from mutual interference, which can cause combining UEs 215 in the same group to impair system performance. For example, beams 220a and 220b used for communication between BS 205 and UEs 215a and 215b, respectively, overlap significantly, which may result in a significant amount of mutual interference between UEs 215a and 215b if communications between BS 205 and UEs 215a and 215b are multiplexed for simultaneous transmission. Therefore, BS 205 may not want to combine UEs 215a and 215b into a group for parallel MU-MIMO communication. However, beams 220a and 220c used for communication between BS 205 and UEs 215a and 215c, respectively, have little overlap, which may result in significantly less interference between UEs 215a and 215c than the desired interference between UEs 215a and 215b. Thus, BS 215 may group UE 215a and UE 215c together for parallel MU-MIMO communication, and expect better performance than if UE 215a and 215b were grouped together. For the same reason, BS 215 may group UE 215b and 215d together, resulting in two groups for parallel MU-MIMO communication. Any combination of UEs 215 is possible (e.g., UE 215a, 215c, and 215d in one group, while UE 215b is in its own group, or UE 215a and 215d in one group, while UE 215b and 215c are in another group), with varying degrees of mutual interference between the UEs in each group.

[0066] Figure 3 An exemplary NZP-CSI-RS resource allocation and transmission scheme 300 for MU-MIMO according to some aspects of the present disclosure is illustrated. The scheme 300 may be employed, for example, by a BS 205 requesting channel estimation and interference measurements from a UE 215. Figure 3In , the x-axis may represent time in some arbitrary units, and the y-axis may represent frequency in some arbitrary units.

[0067] The scenario 300 may involve one BS 205 and four UEs 215 (e.g., UEs 215a-215d). The BS 205 may configure resources (e.g., time-frequency resources) for UE 215a to transmit NZP-CSI-RS 302, NZP-CSI-RS 304, NZP-CSI-RS 306, and NZP-CSI-RS 308. NZP-CSI-RS 302, NZP-CSI-RS 304, NZP-CSI-RS 306, and NZP-CSI-RS 308 are transmitted at the same time. Figure 3 308 for interference measurement. BS 205 may include a pilot precoded with a potential precoding for UE 215b in NZP-CSI-RS 304 for UE 215a to estimate interference from UE 205b, include a pilot precoded with a potential precoding for UE 215c on NZP-CSI-RS 306 for UE 215a to estimate interference from UE 215c, and include a pilot precoded with a potential precoding for UE 215d on NZP-CSI-RS 308 for UE 215a to estimate interference from UE 215d. Precoding may include weighting the amplitude and / or phase of signals at different antenna ports to beamform the signals so that the signal power is concentrated in a certain spatial direction (e.g., Figure 2 Beam 220). Reference Figure 2 In the example shown in , BS 205 may transmit NZP-CSI-RS 304 in a beam direction similar to beam 220 b, NZP-CSI-RS 306 in a beam direction similar to beam 220 c, and NZP-CSI-RS 308 in a beam direction similar to beam 220 d for UE 215 a to measure interference from UE 215 b, UE 215 c, and UE 215 d, respectively. The BS may repeat a similar process for each of UEs 215 b, 215 c, and 215 d to estimate the channel response and estimate the interference from each of the other UEs 215 that may be grouped together for parallel MU-MIMO communication.

[0068] When the BS can apply the scheme 300 to obtain interference measurement information from the served UE and determine the MU-MIMO schedule, the BS may have to transmit many different combinations of precoded reference signals for different UEs. As the number of UEs increases (e.g., to 16, 32, 64, 100, or more) and / or the number of antenna ports increases (e.g., to 8, 16, 64, 128, 256, or more for massive MIMO), the number of combinations of precoded reference signals may be large, and thus the scheme 300 may not be practical (e.g., result in a large amount of resource overhead) and may be difficult to manage.

[0069] Accordingly, the present disclosure provides techniques for a BS to obtain interference information from a UE by transmitting precoding hypotheses (eg, precoding matrices and / or codebook indices) rather than having to transmit many combinations of precoded signals.

[0070] Figure 4 is a block diagram of an exemplary BS 400 according to some aspects of the present disclosure. BS 400 may be as described above. Figure 1 4. As shown, BS 400 may include a processor 402, a memory 404, a channel state module 408, a transceiver 410 including a modem subsystem 412 and an RF unit 414, and one or more antennas 416. These elements may communicate with each other directly or indirectly, for example, via one or more buses.

[0071] The processor 402 may have various features as a special-purpose type of processor. For example, these features may include a CPU, a DSP, an ASIC, a controller, an FPGA device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein. The processor 402 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 in conjunction with a DSP core, or any other such configuration.

[0072] Memory 404 may include cache memory (e.g., cache memory of processor 402), RAM, MRAM, ROM, PROM, EPROM, EEPROM, flash memory, solid-state memory devices, one or more hard disk drives, memristor-based arrays, other forms of volatile and non-volatile memory, or a combination of different types of memory. In some aspects, memory 404 may include non-transitory computer-readable media. Memory 404 may store instructions 406. Instructions 406 may include instructions that, when executed by processor 402, cause processor 402 to perform the operations described herein (e.g., Figure 6-Figure 9 and Figure 11Instructions 406 may also be referred to as program code. The program code may be used to cause the wireless communication device to perform these operations, for example, by causing one or more processors (such as processor 402) to control or command the wireless communication device to do so. The terms "instructions" and "code" should be interpreted broadly to include any type of computer-readable statements. For example, the terms "instructions" and "code" may refer to one or more programs, routines, subroutines, functions, procedures, etc. "Instructions" and "code" may include a single computer-readable statement or many computer-readable statements.

[0073] The channel status module 408 may be implemented via hardware, software, or a combination thereof. For example, the channel status module 408 may be implemented as a processor, circuitry, and / or instructions 406 stored in the memory 404 and executed by the processor 402. In some examples, the channel status module 408 may be integrated within the modem subsystem 412. For example, the channel status module 408 may be implemented by a combination of software components (e.g., executed by a DSP or general-purpose processor) and hardware components (e.g., logic gates and circuitry) within the modem subsystem 412.

[0074] The channel status module 408 may be used in various aspects of the present disclosure, for example, Figure 6-Figure 9 and Figure 11 aspects of . For example, the channel state module 408 may prepare a channel state reporting configuration and transmit it to a first UE 115 of a plurality of UEs 115 that the BS 400 intends to group for MU-MIMO communication. The channel state reporting configuration may be transmitted via media access control (MAC) signaling and may indicate a set comprising one or more interference measurement resources (e.g., resources and precoding information associated with the interference measurement resources). For example, the channel state reporting configuration may indicate a PMI for each resource in the set of interference measurement resources. As part of transmitting the channel state reporting configuration, the channel state module 408 may also transmit a PMI associated with the first UE 115. The precoding information may include a second PMI associated with a first interference measurement resource in the set of interference measurement resources. In practice, the channel state module 408 may be configured to transmit a list of precodings, each of which corresponds to one of the various UEs 115 for which the BS intends the first UE 115 to determine interference measurement information (e.g., as described below in conjunction with Figure 6 and Figure 7 discussed more fully).

[0075] The channel state module 408 may also be configured (in conjunction with the transceiver 410) to transmit a reference signal (e.g., NZP-CSI-RS) to the first UE 115 for the first UE 115 to perform channel response estimation and interference measurement to determine interference between the first UE 115 and other UEs 115 in the plurality of UEs 115. The reference signal may be transmitted in a channel response measurement resource that is different from the resources in the interference measurement resource set. The channel state module 408 may also be configured to refrain from transmitting a second reference signal in the interference measurement resource set because the UE 400 may use the NZP-CSI-RS to perform both channel estimation and interference measurement (e.g., as described below with respect to Figure 6 and Figure 7 discussed more fully).

[0076] The channel state module 408 may also be configured (in conjunction with the transceiver 410 ) to receive a channel state report (e.g., a CSF report, or just a CSF) from the first UE 115 , the channel state report including interference prediction information based on the interference measurement resource set and precoding information transmitted to the first UE 115 .

[0077] In some aspects, the channel state report may be based on a first reference signal and may include interference prediction information, including a rank indicator (RI), a PMI, and / or an expected channel quality indicator (CQI) associated with the first UE 115 based on a first predicted interference associated with a first interference measurement resource in an interference measurement resource set and a corresponding first precoding matrix indicator (PMI). The channel state report may indicate that the first predicted interference associated with the first interference measurement resource and the corresponding first PMI in a set of one or more interference measurement resources and corresponding PMIs provides the least amount of interference to the first UE 115. The channel state report may also include the RI and / or expected CQI associated with the first UE 115 based on the predicted interference associated with the first interference measurement resource and the second PMI. In other words, the BS 400 may receive from the first UE 115 an interference configuration that indicates the least impaired configuration among the options offered to the first UE 115. In some aspects, the channel state report may be time-stamped.

[0078] The channel state module 408 may also determine a group configuration for the plurality of UEs 115 based at least in part on the received channel state report (e.g., in conjunction with the processor 402). The channel state module 408 may group at least a first UE 115 and a second UE 115 of the plurality of UEs 115 for MU-MIMO scheduling based at least in part on the received channel state report. The MU-MIMO scheduling may include a first PMI for the first UE 115, a first RI for the first UE 115, a first MCS for the first UE 115, a second PMI for the second UE 115, a second RI 115 for the second UE, and / or a second MCS for the second UE 115 based on the channel state report.

[0079] In some aspects, the channel state module 408 may also be configured to trigger the first UE 115 to transmit a channel state report aperiodically. In some instances, the trigger may be based on a performance metric (e.g., CQI, target bit error rate (BER), target block error rate (BLER), and / or number of HARQ NACKs) failing to meet a threshold. Alternatively, the channel state module 408 may be configured to trigger the UE 115 to periodically transmit the channel state report. In some aspects, the channel state report may be a MAC layer message or a MAC data payload (e.g., as transmitted on a PUSCH) received via MAC layer signaling. In some instances, HARQ may be applied to the PUSCH data to increase reliability, as described above with respect to Figure 1As discussed. The channel report configuration can also be transmitted via MAC signaling (e.g., in a MAC header), which can provide faster signaling than RRC reconfiguration. Receiving the report via MAC signaling can reduce the load on the control channel (e.g., PUCCH), thereby reducing the impact on the uplink throughput of the network, and allows detailed reporting - using large-sized CSF reports - including time and configuration stamps. For example, each CSF report can include a timestamp indicating the time when the CSF report was generated or transmitted. Additionally or alternatively, each CSF report can include a configuration stamp indicating the report configuration used to generate the CSF report. In this way, the timestamp and configuration stamp can reduce errors caused by not receiving the configuration due to HARQ failure or the first UE 115 failing to transmit the CSF report. In general, including a timestamp and / or configuration stamp in the CSF report allows the channel state module 408 to correctly interpret the CSF report, thereby avoiding mismatches between the transmitted report configuration and the received report. In some aspects, the channel state module 408 can configure the first UE 115 to report the CSF report at a rate adapted to the data throughput and / or traffic load. In some aspects, the channel state module 408 may configure the first UE 115 to report a CSF report as part of a handover (HO) procedure to assist the network in network optimization. For example, the channel state module 408 may report a CSF report based on the NZP-CSI-RS resources from the target BS of the HO while using the NZP-CSI-RS resources from the current BS as an interference source.

[0080] As another example (any or all aspects combinable with the previous examples), the channel state module can be configured (e.g., in combination with the transceiver 410) to transmit a channel state report configuration to a first UE in a plurality of UEs, the channel state report configuration indicating a set of one or more measurement resources and at least one of precoding information or a rank indication associated with the set of one or more interference measurement resources. The channel state module 408 can also be configured to indicate (e.g., in a channel configuration report) a first PMI and a second PMI, and / or a first RI and a second RI. In practice, the channel state module 408 can transmit any number of PMIs (each corresponding to a UE 115 in the plurality of UEs) and any number of RIs for which the channel state module 408 desires information. The channel state module 408 can also be configured to transmit a plurality of first reference signals to the first UE 115 at different times within a time period in a first channel response measurement resource that is different from the set of one or more measurement resources. The channel state module 408 may also be configured to transmit an indication to the first UE 115 (eg, in a channel configuration report) of how much channel state feedback the first UE 115 should provide.

[0081] The channel state module 408 may also be configured to receive a channel state report from the first UE 115, the channel state report including a plurality of expected CQIs within a time period based on a set of one or more measurement resources and at least one of precoding information or a rank indication. The channel state report may be based on the plurality of first reference signals and may include a first CQI for a first RI and a second CQI for a second RI (which may be different from the first RI). The first CQI for the first RI and the second CQI for the second RI may be based on an interference measurement resource set. The channel state report may also include a first MCS for the first RI and a second MCS for the second RI, the first MCS and the second MCS being based on the interference measurement resource set. The channel state report may also include a CQI history based on the measurement resource set at multiple time instances. The channel state report may also include a history of channel state feedback based on the measurement resource set and at least one of precoding information or a rank indication (which may include a plurality of expected CQIs). Each channel state feedback may be associated with a timestamp.

[0082] The channel state module 408 may also be configured to determine link adaptation (e.g., OLLA) for the first UE 115 based at least in part on the channel state report. As part of determining link adaptation, the channel state module 408 may be configured to determine an update to the PMI, RI, and / or MCS used for communicating with the first UE 115.

[0083] As shown, transceiver 410 may include a modem subsystem 412 and an RF unit 414. Transceiver 410 may be configured to communicate bidirectionally with other devices, such as UE 115 and / or 500 and / or another core network element. Modem subsystem 412 may be configured to modulate and / or encode data according to an MCS (e.g., an LDPC coding scheme, a turbo coding scheme, a convolutional coding scheme, a digital beamforming scheme, etc.). The RF unit 414 may be configured to process (e.g., perform analog-to-digital conversion or digital-to-analog conversion, etc.) modulated / coded data (e.g., PDSCH signals, PDCCH signals, DL data, scheduling grants, RRC configurations, MAC messages, CSF configurations, reference signals, CSI-RS, NZP-CSI-RS, CSF report aperiodic triggers, precoding hypotheses (e.g., potential PMIs and / or codebook indices)) from the modem subsystem 412 (on outbound transmissions) or from transmissions originating from another source (such as UE 115 and / or UE 500). The RF unit 414 may be further configured to perform analog beamforming in conjunction with digital beamforming. Although shown as being integrated together in the transceiver 410, the modem subsystem 412 and / or the RF unit 414 may be separate devices that are coupled together at the BS 105 to enable the BS 105 to communicate with other devices.

[0084] The RF unit 414 may provide modulated and / or processed data (e.g., a data packet (or, more generally, a data message that may include one or more data packets and other information)) to the antenna 416 for transmission to one or more other devices. The antenna 416 may further receive data messages transmitted from other devices and provide the received data messages for processing and / or demodulation at the transceiver 410. The transceiver 410 may provide the demodulated and decoded data (e.g., PUSCH signals, UL data, MAC messages, CSF reports, CQI reports, CQI history) to the channel state module 408 for processing. The antenna 416 may include multiple antennas of similar or different designs to maintain multiple transmission links.

[0085] In one example, the transceiver 410 is configured to transmit a channel state report configuration to a first UE among a plurality of UEs, the channel state report configuration indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources. The transceiver 410 is further configured to receive a channel state report from the first UE, the channel state report including interference prediction information based on the set of one or more interference measurement resources and the precoding information. The processor 402 is configured to determine a group configuration for the plurality of UEs based at least in part on the received channel state report.

[0086] In another example, the transceiver 410 is configured to transmit a channel state report configuration to a first UE among a plurality of UEs, the channel state report configuration indicating a set of one or more measurement resources and at least one of precoding information or a rank indication associated with the set of one or more interference measurement resources. The transceiver 410 is further configured to receive a channel state report from the first UE, the channel state report including a plurality of expected CQIs within a time period based on the set of one or more interference measurement resources and at least one of the precoding information or the rank indication, and the processor 402 is configured to determine link adaptation for the first UE based at least in part on the received channel state report.

[0087] Figure 5 is a block diagram of an exemplary UE 500 according to some aspects of the present disclosure. The UE 500 may be as described above. Figure 1 As shown, UE 500 may include a processor 502, a memory 504, a channel state module 508, a transceiver 510 (including a modem subsystem 512 and a radio frequency (RF) unit 514), and one or more antennas 516. These elements may communicate with each other directly or indirectly, for example, via one or more buses.

[0088] The processor 502 may include a central processing unit (CPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a controller, a field programmable gate array (FPGA) device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein. The processor 502 may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0089] The memory 504 may include cache memory (e.g., cache memory of the processor 502), random access memory (RAM), magnetoresistive RAM (MRAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, a solid-state memory device, a hard drive, other forms of volatile and non-volatile memory, or a combination of different types of memory. In one aspect, the memory 504 includes a non-transitory computer-readable medium. The memory 504 may store or have recorded thereon instructions 506. The instructions 506 may include instructions that, when executed by the processor 502, cause the processor 502 to perform the various aspects of the present disclosure described herein with reference to the UE 115 (e.g., Figure 6-Figure 8 、 Figure 10 as well as Figure 12 Instructions 506 may also be referred to as program code, which may be broadly interpreted as including instructions for the operations described above. Figure 4 Any type of computer-readable statement in question.

[0090] The channel status module 508 can be implemented via hardware, software, or a combination thereof. For example, the channel status module 508 can be implemented as a processor, circuitry, and / or instructions 506 stored in the memory 504 and executed by the processor 502. In some examples, the channel status module 508 can be integrated within the modem subsystem 512. For example, the channel status module 508 can be implemented by a combination of software components (e.g., executed by a DSP or general-purpose processor) and hardware components (e.g., logic gates and circuitry) within the modem subsystem 512.

[0091] The channel status module 508 may be used in various aspects of the present disclosure, for example, Figure 6-Figure 8 、 Figure 10 and Figure 12aspects of . For example, the channel state module 508 may be configured to receive a channel state report configuration from the BS 105 (e.g., via MAC signaling, in conjunction with the transceiver 510), the channel state report configuration indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources. The channel state report configuration may also indicate a PMI for each resource in the set of one or more interference measurement resources. As part of receiving the channel state report, the channel state module 508 may also receive a PMI associated with the UE 500 from the BS 105, and the precoding information may include a second PMI associated with a first interference measurement resource in the set of interference measurement resources. The channel state module 508 may also be configured to receive a first reference signal (e.g., NZP-CSI-RS) from the BS in a channel measurement resource different from the set of one or more interference measurement resources. Based on the first reference signal, the channel state module 508 may determine a channel response. The channel state module 508 may also be configured to determine interference prediction information (e.g., as described below with respect to Figure 6 and Figure 7 In some aspects, the channel state module 508 may be configured to determine the interference prediction information according to equation (1) discussed below.

[0092] The channel state module 508 may also be configured to transmit a channel state report to the BS 105 (e.g., via MAC signaling, in conjunction with the transceiver 510), the channel state report including interference prediction information based on the interference measurement resource set and precoding information. The report may indicate the RI, PMI, and / or expected CQI associated with the UE 500 based on a first predicted interference associated with a first interference measurement resource in the interference measurement resource set and a corresponding first PMI. The channel state module 508 may also be configured to select a first interference measurement resource from the interference measurement resource set based on the first predicted interference associated with the first interference measurement resource and the first PMI having less interference to the UE 500 than a second predicted interference associated with a second interference measurement resource in the interference measurement resource set and a corresponding second PMI. The report may also indicate that the first predicted interference associated with the first interference measurement resource and the corresponding first PMI in the interference measurement resource set and the corresponding PMI provides the least amount of interference to the UE 500. The report may also indicate the RI or expected CQI associated with the UE 500 based on the predicted interference associated with the first interference measurement resource and the second PMI. In some aspects, the channel state report may be time stamped.

[0093] Channel state module 508 may also be configured to receive scheduling information (eg, determined by BS 105) based on the channel state report (eg, in conjunction with transceiver 510). The scheduling information may include PMI, RI, and / or MCS.

[0094] In another example, the channel state module 508 can be configured to receive a channel state reporting configuration from the BS 105, the channel state reporting configuration indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources. The channel state module 508 can also be configured to receive an indication of the first RI and the second RI and / or the first PMI and the second PMI for which the BS 105 desires feedback. The channel state module 508 can also be configured to receive an indication of the amount of channel state feedback that the channel state module 508 will transmit to the BS as part of the channel feedback history.

[0095] The channel state module 508 may also be configured to transmit a channel state report to the BS, the channel state report including a plurality of expected CQIs within a time period based on a measurement resource set and at least one of precoding information or a rank indication associated with the set of one or more measurement resources. Based on the measurement resource set, the report may include a first CQI for a first RI and a second CQI for a second RI (wherein the first and second RIs are different). Based on the measurement resource set, the report may also include a first CQI for a first PMI and a second CQI for a second PMI (wherein the first and second PMIs are different). Based on the measurement resource set, the report may also include a first MCS for the first RI and a second MCS for the second RI. The report may also include a CQI history based on the measurement resource set at multiple time instants. The report may also include a history of channel state feedback, the history of channel state feedback including a plurality of expected CQIs based on the measurement resource set and the precoding information. In addition, each channel state feedback may be associated with a timestamp.

[0096] The channel state module 508 may also be configured to receive scheduling information from the BS 105 based on the received channel state report, the scheduling information including PMI, RI, and / or MCS.

[0097] As shown, transceiver 510 may include a modem subsystem 512 and an RF unit 514. Transceiver 510 may be configured to communicate bidirectionally with other devices, such as BS 105. Modem subsystem 512 may be configured to modulate and / or encode data from memory 504 and / or channel state module 508 according to a modulation and coding scheme (MCS) (e.g., a low-density parity check (LDPC) coding scheme, a turbo coding scheme, a convolutional coding scheme, a digital beamforming scheme, etc.). RF unit 514 may be configured to process (e.g., perform analog-to-digital conversion or digital-to-analog conversion, etc.) modulated / encoded data (e.g., PUSCH signals, UL data, CSF reports, CQI reports, CQI history) from modem subsystem 512 (on out-of-band transmissions) or from another source, such as UE 115 or BS 105. RF unit 514 may further be configured to perform analog beamforming in conjunction with digital beamforming. Although shown as integrated together in the transceiver 510, the modem subsystem 512 and the RF unit 514 may be separate devices that are coupled together at the UE 115 to enable the UE 115 to communicate with other devices.

[0098] The RF unit 514 may provide modulated and / or processed data (e.g., data packets (or, more generally, data messages that may include one or more data packets and other information)) to the antenna 516 for transmission to one or more other devices. The antenna 516 may further receive data messages transmitted from the other devices. The antenna 516 may provide the received data messages for processing and / or demodulation at the transceiver 510. The transceiver 510 may provide the demodulated and decoded data (e.g., PDSCH signals, PDCCH signals, DL data, scheduling grants, RRC configurations, MAC messages, CSF configurations, reference signals, CSI-RS, NZP-CSI-RS, CSF report aperiodic triggers, precoding hypotheses (e.g., potential PMIs and / or codebook indices)) to the channel state module 508 for processing. The antenna 516 may include multiple antennas of similar or different designs to maintain multiple transmission links. The RF unit 514 may configure the antenna 516.

[0099] In one aspect, the UE 500 may include multiple transceivers 510 that implement different RATs (e.g., NR and LTE). In one aspect, the UE 500 may include a single transceiver 510 that implements multiple RATs (e.g., NR and LTE). In one aspect, the transceiver 510 may include various components, where different combinations of components may implement different RATs.

[0100] In one example, the transceiver 510 is configured to receive a channel state report configuration from a BS, the channel state report configuration indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources, and transmit a channel state report to the BS, the channel state report including interference prediction information based on the set of one or more interference measurement resources and the precoding information. The transceiver 510 can coordinate with other components of the UE 500 (e.g., the processor 402 and the channel state module 508).

[0101] In another example, the transceiver 510 is configured to receive a channel state report configuration from a BS, the channel state report configuration indicating a set of one or more measurement resources and at least one of precoding information or a rank indication associated with the set of one or more interference measurement resources. The transceiver is further configured to transmit a channel state report to the BS, the channel state report including a plurality of expected CQIs within a time period based on the set of one or more measurement resources and at least one of precoding information or a rank indication associated with the set of one or more measurement resources.

[0102] Figure 6 about Figure 7 Let's discuss to explain channel state feedback based on interference prediction. Figure 6 6 is an exemplary sequence diagram illustrating a communication sequence 600 according to some aspects of the present disclosure. Sequence 600 may be performed by a BS 205 (which may be BS 105 or 400) requesting channel estimation and interference measurement and a number of UEs 215a-215d (which may be UE 115 or 500) requesting channel estimation and interference measurement in order to divide a set of UEs 215 into groups for parallel MU-MIMO communication. For simplicity, one BS 205 and four UEs 215 are shown, although any number of UEs 215 may be considered.

[0103] At steps 602a-602d, BS 205 transmits various CSF configurations (also referred to herein as channel reporting configurations), as described in detail below, to UE 215. The CSF configuration may indicate one of various reporting modes, as will be discussed more fully below.

[0104] For example, at step 602a, BS 205 transmits a CSF configuration to UE 215a. The CSF configuration may provide UE 215a with details about an assumed or potential grouping of UE 215a for which BS 205 is requesting interference measurement information, as well as an indication of what type of information BS 205 is requesting in a corresponding CSF report. For example, the CSF configuration may include a list of potential or assumed precoders (e.g., PMIs or codebook indices) that UE 215a may use to estimate interference from UEs 215b-215d. For example, the list may include a PMI corresponding to UE 215b, a PMI corresponding to UE 215c, and a PMI corresponding to UE 215d. In some examples, aspects of step 602a may be implemented as described with reference to FIG. Figure 4 The channel status module 408 described above is executed.

[0105] At step 602b, BS 205 transmits a CSF configuration to UE 215b (e.g., via MAC signaling). The CSF configuration may provide UE 215b with details about an assumed or potential grouping of UEs 215 for which BS 205 is requesting interference measurement information, as well as an indication of what type of information BS 205 is requesting in a corresponding CSF report. For example, the CSF configuration may include a list of potential or assumed precoders (e.g., PMIs or codebook indices) that UE 215b may use to estimate interference from UEs 215a and 215c-215d. For example, the list may include a PMI corresponding to UE 215a, a PMI corresponding to UE 215c, and a PMI corresponding to UE 215d. In some examples, aspects of step 602b may be implemented as described with reference to FIG. Figure 4 The channel status module 408 described above is executed.

[0106] At step 602c, BS 205 transmits a CSF configuration to UE 215c (e.g., via MAC signaling). The CSF configuration may provide UE 215c with details about an assumed or potential grouping of UEs 215 for which BS 205 is requesting interference measurement information, as well as an indication of what type of information BS 205 is requesting in a corresponding CSF report. For example, the CSF configuration may include a list of potential or assumed precoders (e.g., PMIs or codebook indices) that UE 215c may use to estimate interference from UEs 215a, 215b, and 215d. For example, the list may include a PMI corresponding to UE 215a, a PMI corresponding to UE 215b, and a PMI corresponding to UE 215d. In some examples, aspects of step 602c may be implemented as described with reference to FIG. Figure 4 The channel status module 408 described above is executed.

[0107] At step 602d, BS 205 transmits a CSF configuration to UE 215d (e.g., via MAC signaling). The CSF configuration may provide UE 215d with details about an assumed or potential grouping of UE 215 for which BS 205 is requesting interference measurement information, as well as an indication of what type of information BS 205 is requesting in a corresponding CSF report. For example, the CSF configuration may include a list of potential or assumed precoders (e.g., PMIs or codebook indices) that UE 215d may use to estimate interference from UEs 215a-215c. For example, the list may include a PMI corresponding to UE 215a, a PMI corresponding to UE 215b, and a PMI corresponding to UE 215c. In some examples, aspects of step 602d may be implemented as described with reference to FIG. Figure 4 The channel status module 408 described above is executed.

[0108] In step 604, BS 205 may use, for example, Figure 7 The scheme 700 discussed in detail in the description of FIG transmits a reference signal to each UE 215 on a channel measurement resource. The reference signal can be an NZP-CSI-RS that includes a pilot signal (e.g., without precoding) for channel response estimation. In some examples, aspects of step 604 can be performed as described in reference to FIG. Figure 4 The channel status module 408 described above is executed.

[0109] At step 606a, UE 215a uses the NZP-CSI-RS transmitted at step 604 and the CSF configuration transmitted at step 602a to determine interference prediction information. UE 215a may use the same NZP-CSI-RS for channel estimation and for both reconstructing the interfering stream and determining the predicted interference from UEs 215b-215d based on the precoding information for each of UEs 215b-215d in the CSF report, e.g., according to equation (1) below. In some examples, aspects of step 606a may be implemented as described with reference to FIG. Figure 5 The channel status module 508 described above is executed.

[0110] At step 606b, UE 215b determines interference prediction information using the NZP-CSI-RS transmitted at step 604 and the CSF configuration transmitted at step 602b. UE 215b may use the same NZP-CSI-RS for channel estimation and for both reconstructing the interfering streams and determining the predicted interference from UEs 215a and 215c-215d based on the precoding information in the CSF report for each of UEs 215a and 215c-215d. In some examples, aspects of step 606b may be implemented as described with reference to FIG. Figure 5The channel status module 508 described above is executed.

[0111] At step 606c, UE 215c determines interference prediction information using the NZP-CSI-RS transmitted at step 604 and the CSF configuration transmitted at step 602c. UE 215c may use the same NZP-CSI-RS for channel estimation and for both reconstructing the interfering streams and determining the predicted interference from UEs 215a-215b and 215d based on the precoding information for each of UEs 215a-215b and 215d in the CSF report. In some examples, aspects of step 606c may be implemented as described with reference to FIG. Figure 5 The channel status module 508 described above is executed.

[0112] At step 606d, UE 215d determines interference prediction information using the NZP-CSI-RS transmitted at step 604 and the CSF configuration transmitted at step 602d. UE 215d may use the same NZP-CSI-RS for channel estimation and for both reconstructing the interfering streams and determining the predicted interference from UEs 215a-215c based on the precoding information for each of UEs 215a-215c in the CSF report. In some examples, aspects of step 606d may be implemented as described with reference to FIG. Figure 5 The channel status module 508 described above is executed.

[0113] In steps 608a-608d, UEs 215a-215d each transmit a CSF report (e.g., via MAC signaling) based on the channel response estimates and interference prediction information they determined in steps 606a-606d. In some examples, aspects of steps 608a-608d may be implemented as described with reference to FIG. Figure 5 The channel status module 508 described above is executed.

[0114] At step 610, BS 205 determines the grouping configuration (i.e., how to divide UE 215 into groups for parallel MU-MIMO communication) based on the CSF reports transmitted by UE 215 at steps 608a-608d. In some examples, aspects of step 610 can be as described with reference to Figure 4 The channel status module 408 described above is executed.

[0115] Figure 7An exemplary NZP-CSI-RS resource allocation and transmission scheme 700 for MU-MIMO according to some aspects of the present disclosure is illustrated. The scheme 700 may be employed, for example, by a BS 105, 205, or 400 requesting channel estimation and interference measurements from UEs 115, 215, or 500 in order to partition a set of UEs 215 into groups for parallel MU-MIMO communication. Figure 7 In , the x-axis may represent time in some arbitrary units, and the y-axis may represent frequency in some arbitrary units.

[0116] For simplicity, the scheme 700 is illustrated using one BS 205 and four UEs 215 (e.g., UEs 215a-215d), although any number of UEs 215 may be considered. The BS 205 may transmit an NZP-CSI-RS 702 to the UE 205a. Compared to the scheme 300, the same NZP-CSI-RS 702 may be used for both channel estimation and interference measurement. For example, the NZP-CSI-RS 702 may include a pilot (e.g., without precoding) for the UE 205a to perform channel estimation. The BS 205 may provide information to the UE 215a to allow the UE 215a to reconstruct the interference stream using a single NZP-CSI-RS 702 to account for potential interference from the UEs 215b-215d being considered for parallel scheduling, as shown in FIG. Figure 6 Detailed discussion. This information may include, for example, a list of potential or hypothetical precoders (e.g., PMIs or codebook indices) that UE 215a may use to estimate interference from UEs 215b-215d. For example, the list may include a PMI corresponding to UE 215b, a PMI corresponding to UE 215c, and a PMI corresponding to UE 215d. UE 215a may use the precoders in the list to estimate the interference caused by UEs 215b-215d based on a channel response estimate (determined by UE 215a using NZP-CSI-RS 702) and the precoders corresponding to each of UEs 215b-215d.

[0117] As an example, the BS 205 may have 32 transmit antenna ports and the UE 215 may have 4 receive antenna ports. The NZP-CSI-RS 702 may include 32 pilots (shown by each patterned filled box), each pilot being transmitted via one of the 32 antenna ports. Figure 2 and Figure 3In the example discussed, BS 205 may consider grouping one or more of UEs 215 for MU-MIMO. To enable UE 215a to estimate or predict interference from other UEs 215b-215d, BS 205 may provide UE 215a with potential precoding to be used for UEs 215b-215d. For example, the potential precoding may be represented by a precoding matrix, denoted as W. 32xL , where L may represent the number of interferers (e.g., for UE 215b-d, L=3). Upon receiving NZP-CS-RS 702, UE 215 may determine a channel response based on NZP-CS-RS 702, denoted as a 4 by 32 channel matrix H 4x32 In determining the channel response H between UE 215a and BS 205 4x32 Thereafter, UE 215 may respond to the channel H based on 4x32 and precoding W 32xL To determine or predict the interference from UE 215b-215d. For example, the predicted interference can be calculated according to the following equation (1):

[0118] H int = [h int,0, h int,1, h int,Lint-1 ] = H 4x32 WH 32xL , (1)

[0119] Among them H int may represent the predicted interference from UEs 215b-215d. int,0 、h int,1 、h int,2 The predicted interference from UEs 215b, 215c, and 215d may be represented respectively.

[0120] Based on the channel estimate and the interference estimate, UE 215a may prepare and transmit a channel state feedback report to BS 205 to indicate the selected NZP-CSI-RS resource configuration and / or corresponding precoding that may produce the least amount of interference at UE 215a. The BS may repeat this process for each of UEs 215b-215d, as shown in FIG. Figure 6 As described in .

[0121] In some aspects, the CSF reporting configuration may indicate a reporting mode, such as a CRI-RI-PMI-CQI mode, a CRI-RI-L1 mode, and / or a CRI-RI-CQI mode. For example, in the CRI-RI-PMI-CQI mode, the resulting CSF report may include the best RI and PMI for a particular CRI (e.g., indicating the resource in which the CSI-RS is transmitted) and the corresponding expected CQI based on the RI and PMI. In some instances, the BS 205 may use the CRI-RI-PMI-CQI mode to collect predicted interference information from UEs 215a, 215b, 215c, and / or 215d to determine the best grouping for UEs 215a-215d. The BS 205 may use the CRI-RI-CQI mode after it has determined some potential groupings (e.g., grouping UEs 215a and 215b for MU-MIMO). For example, BS 205 may transmit a precoded data stream (e.g., precoded according to the PMI selected for UE 215a) and provide UE 215a with the PMI selected for UE 215b and request UE 215a to report in CRI-RI-CQI mode. In CRI-RI-CQI mode, the resulting CSF report may include the best RI for UE 215a determined based on the precoded data stream, and the interference predicted based on the provided PMI (for UE 215b) and the corresponding expected CQI. In CRI-RI-L1 mode, the resulting CSF report may include the best directional beam for communication between UE 215 and BS 205 (e.g., via RI indication and / or beam index) and the corresponding layer 1 reference signal received power (L1-RSRP) measurement from that beam.

[0122] Figure 8 8 is an exemplary sequence diagram illustrating a communication sequence 800 according to some aspects of the present disclosure. Sequence 800 may be performed by a BS 105 (which may be BS 205 or 400) and a UE (which may be UE 215 or 500). For simplicity, one BS 105 and one UE 115 are shown, although other combinations of BSs 105 and UEs 115 are possible.

[0123] At step 802, BS 105 transmits a channel report configuration (also referred to herein as a CSF configuration) to UE 115 using, for example, MAC signaling. The CSF configuration may indicate an interference measurement resource set and precoding information associated with the interference measurement resource set. The CSF configuration may also include a list of RIs and / or a list of PMIs to be included in the report for MCS calculation, and / or the number of desired channel state feedbacks (e.g., the last N channel state feedbacks), as described in [Channel State Feedback Parameters]. Figure 4 In some examples, aspects of step 802 may be implemented as described in reference to Figure 4 The channel status module 408 described above is executed.

[0124] At step 804, BS 105 and UE 115 communicate based on the scheduling parameters. In some examples, aspects of step 804 may be performed as described in reference to Figure 5 The channel status module 508 described above is executed.

[0125] During time period 805, BS 105 may transmit several CSI-RSs (e.g., CSI-RS 702) to UE 115, and UE 115 may determine an expected CQI based on the CSI-RSs and the CSF configuration. For example, UE 115 may determine a channel response from the CSI-RSs and determine predicted interference from the channel response and precoding information according to equation (1) above. UE 115 may calculate an expected CQI based on the predicted interference and the channel response (e.g., based on an SNR estimate).

[0126] For example, at step 806a, BS 105 transmits CSI-RS to UE 115. In some examples, aspects of step 806a may be performed as described with reference to Figure 4 The channel status module 408 described above is executed.

[0127] In step 807a, the UE 115 determines the expected CQI at time t(1) based on the CSI-RS and predicted interference (e.g., interference predicted based on precoding information in the CSF configuration) using the mechanisms discussed above and stores it in a history (e.g., using memory 504). By time t(n), multiple CSI-RS are transmitted and multiple expected CQIs are determined and stored in the history. In some aspects, the UE 115 may determine a CQI or MCS for each PMI in the PMI list. In some aspects, the UE 115 may determine a CQI or MCS for each RI in the RI list. In some examples, aspects of step 807a may be performed as described in reference to Figure 5 The channel status module 508 described above is executed.

[0128] At step 806n, BS 105 transmits the last CSI-RS of time period 805. In some examples, aspects of step 806n may be as described with reference to Figure 4 The channel status module 408 described above is executed.

[0129] At step 807n, the UE 115 determines the desired CQI at time t(n) and stores the CQI in the history. In some examples, aspects of step 807n may be as described with reference to Figure 5The channel status module 508 described above is executed.

[0130] At step 808, the BS transmits a report history trigger to the UE 115, thereby prompting the UE to prepare and transmit a channel state report (eg, a CSF report). In some examples, aspects of step 808 may be performed as described with reference to FIG. Figure 4 The channel status module 408 described above is executed.

[0131] At step 810, UE 115 generates a CSF report, which may include the expected CQI determined during time period 805, the recommended MCS for different RIs and / or different PMIs indicated in the CSF configuration, and a history of channel state feedback. In some instances, UE 115 may generate the CSF report based on the reporting mode indicated in the reporting configuration (e.g., historical CQI reporting mode, list reporting mode, and / or historical CSF reporting). For historical CQI reporting mode, the CSF report may include the last CQI report (e.g., the most recently calculated expected CQI). For list reporting mode, the CSF report may include a CQI list, e.g., one CQI for each RI in the RI list provided by the reporting configuration. Alternatively or additionally, the CSF report may include a CQI list, e.g., one CQI for each PMI in the PMI list provided by the reporting configuration. For historical CSF reporting, the CSF report may include the last N CSF reports (e.g., the value N may be provided by the reporting configuration). In some instances, the CSF report may include CQI history for certain CRI-PMI-RI combinations (e.g., extensions to codebook restrictions). For example, the BS may send a valid PMI list based on previous reports for each requested report. In some examples, aspects of step 810 may be as described with reference to Figure 5 The channel status module 508 described above is executed.

[0132] At step 812, UE 115 transmits a CSF report to BS 115 (eg, using MAC signaling). In some examples, aspects of step 812 may be performed as described with reference to FIG. Figure 5 The channel status module 508 described above is executed.

[0133] At step 814, BS 105 performs link adaptation (e.g., OLLA) based at least in part on the CSF report. During the link adaptation process, BS 105 may update the PMI, RI, and / or MCS for the link with UE 115 based on the data transmitted on the CSF report. For example, if the CQI has improved (e.g., a higher CQI than the previous reporting period), BS 105 may select a higher MCS level. Conversely, if the CQI has degraded (e.g., a lower CQI than the previous reporting period), BS 105 may select a lower MCS level. The BS may also change the RI (e.g., utilizing a different number of spatial layers) and / or PMI to provide optimal performance for UE 115. In some instances, BS 105 may analyze the CQI history per RI or per PMI to determine channel variations. In some instances, if the link is experiencing jitter at the time BS 105 performs link adaptation, the BS may rely on older CQIs transmitted as part of the feedback history to determine more accurate PMI, RI, and / or MCS values ​​for the link. In some examples, aspects of step 814 may be implemented as described with reference to Figure 4 The channel status module 408 described above is executed.

[0134] Figure 9 900 is a flow chart of a wireless communication method 900 according to some aspects of the present disclosure. Aspects of the method 900 may be performed by a computing device (e.g., a processor, processing circuitry, and / or other suitable components) of a wireless communication device or other suitable means for performing the steps. For example, a wireless communication device (such as BS 105, 205, or 400) may utilize one or more components (such as processor 402, memory 404, channel state module 408, transceiver 410, modem 412, and one or more antennas 416) to perform the steps of the method 900. The method 900 may be implemented in the same manner as described above with reference to FIG. Figure 6-Figure 8 The methods 900 and 800 are similar in structure to those described in the sequence 600, the scheme 700, and the sequence 800. As illustrated, the method 900 includes several enumerated steps, but aspects of the method 900 may include additional steps before, after, and between the enumerated steps. In some aspects, one or more of the enumerated steps may be omitted or performed in a different order.

[0135] At block 902, BS 105 may transmit a channel state reporting configuration to a first UE 115 in a plurality of UEs 115. In some examples, BS 105 may utilize one or more components, such as processor 402, memory 404, channel state module 408, transceiver 410, and modem 412, to perform aspects of block 902.

[0136] In some aspects, a channel state report configuration may be transmitted via media access control (MAC) signaling and may indicate a set of one or more interference measurement resources and precoding information associated with the interference measurement resources. The channel state report configuration may indicate a PMI for each resource in the interference measurement resource set. As part of transmitting the channel state report configuration, the BS may also transmit a PMI associated with the first UE 115. The precoding information may include a second PMI associated with the first interference measurement resource in the interference measurement resource set. In some instances, the BS 105 may transmit a reference signal (e.g., NZP-CSI-RS) to the first UE 115 for the first UE 115 to perform channel response estimation and interference measurement to determine mutual interference between the first UE 115 and other UEs 115 in the multiple UEs 115. The reference signal may be transmitted in a channel response measurement resource that is different from the resources in the interference measurement resource set. In some instances, the BS 105 may also suppress transmitting a second reference signal in the interference measurement resource set.

[0137] At block 904, BS 105 may receive a channel state report (e.g., via MAC signaling) from first UE 115, the channel state report including interference prediction information based on a set of one or more interference measurement resources and precoding information. In some examples, BS 105 may utilize one or more components, such as processor 402, memory 404, channel state module 408, transceiver 410, and modem 412, to perform aspects of block 904.

[0138] In some aspects, the channel state report may be based on a first reference signal and may include interference prediction information including a rank indicator (RI), a PMI, and / or an expected channel quality indicator (CQI) associated with the first UE 115 based on a first predicted interference associated with a first interference measurement resource in an interference measurement resource set and a corresponding first precoding matrix indicator (PMI). The channel state report may indicate that the first predicted interference associated with the first interference measurement resource and the corresponding first PMI in a set of one or more interference measurement resources and each corresponding PMI provides the least amount of interference to the first UE. The channel state report may also include the RI and / or expected CQI associated with the first UE based on the predicted interference associated with the first interference measurement resource and a second PMI. In some instances, the channel state report may be time-stamped.

[0139] At block 906, the BS may determine a group configuration for the plurality of UEs 115 based at least in part on the received channel state reports. In some examples, the BS 105 may utilize one or more components, such as the processor 402, memory 404, channel state module 408, transceiver 410, and modem 412, to perform aspects of block 906.

[0140] In some aspects, the BS may group at least a first UE 115 and a second UE 115 of the plurality of UEs 115 for MU-MIMO scheduling based at least in part on the received channel state report. The MU-MIMO scheduling may include a first PMI for the first UE 115, a first RI for the first UE 115, a first MCS for the first UE 115, a second PMI for the second UE 115, a second RI 115 for the second UE, and / or a second MCS for the second UE 115 based on the channel state report.

[0141] Figure 10 1 is a flow chart of a wireless communication method 1000 according to some aspects of the present disclosure. Aspects of the method 1000 may be performed by a computing device (e.g., a processor, processing circuitry, and / or other suitable components) of a wireless communication device or other suitable means for performing the steps. For example, a wireless communication device (such as UE 115, 215, or 500) may utilize one or more components (such as a processor 502, a memory 504, a channel state module 508, a transceiver 510, a modem 512, and one or more antennas 516) to perform the steps of the method 1000. The method 1000 may be implemented in the same manner as described above with reference to FIG. Figure 6-Figure 8 The mechanisms described in sequence 600, scheme 700, and sequence 800 are similar. As illustrated, method 1000 includes several enumerated steps, but aspects of method 1000 may include additional steps before, after, and between these enumerated steps. In some aspects, one or more of the enumerated steps may be omitted or performed in a different order.

[0142] At block 1002, the UE 115 may receive a channel state reporting configuration (e.g., via MAC signaling) from the BS 105, the channel state reporting configuration indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources. In some examples, the UE 115 may utilize one or more components (such as the processor 502, the memory 504, the channel state module 508, the transceiver 510, and the modem 512) to perform aspects of block 1002.

[0143] In some aspects, the channel state report configuration may further indicate a PMI for each resource in the set of one or more interference measurement resources. As part of receiving the channel state report, the UE 115 may further receive a PMI associated with the UE 115 from the BS 105, and the precoding information may include a second PMI associated with a first interference measurement resource in the interference measurement resource set. The channel state module may further be configured to receive a first reference signal (e.g., NZP-CSI-RS) from the BS 105 in a channel measurement resource different from the set of one or more interference measurement resources. Based on the first reference signal, the UE 115 may determine a channel response. The UE 115 may also determine interference prediction information based on the interference measurement resource set, the precoding information, and / or the determined channel response.

[0144] At block 1004, UE 115 may transmit a channel state report (e.g., via MAC signaling) to BS 105, the channel state report including interference prediction information based on the interference measurement resource set and precoding information. In some examples, UE 115 may utilize one or more components (such as processor 502, memory 504, channel state module 508, transceiver 510, and modem 512) to perform aspects of block 1004.

[0145] In some aspects, the report may indicate an RI, PMI, and / or expected CQI associated with UE 115 based on a first predicted interference associated with a first interference measurement resource and a corresponding first PMI in the set of one or more interference measurement resources. UE 115 may also be configured to select a first interference measurement resource from the set of interference measurement resources based on a first predicted interference associated with the first interference measurement resource and the first PMI providing less interference to UE 115 than a second predicted interference associated with a second interference measurement resource and a corresponding second PMI in the set of one or more interference measurement resources. The report may indicate that the first predicted interference associated with the first interference measurement resource and the corresponding first PMI in the set of interference measurement resources and the corresponding PMIs provides the least amount of interference to UE 115. The report may also indicate an RI or expected CQI associated with UE 115 based on the predicted interference associated with the first interference measurement resource and the second PMI. In some aspects, the channel state report may be time-stamped.

[0146] In some aspects, the UE 115 may also receive scheduling information based on the channel state report (e.g., scheduling information determined by the BS 105). The scheduling information may include PMI, RI, and / or MCS.

[0147] Figure 111 is a flow chart of a wireless communication method 1100 according to some aspects of the present disclosure. Aspects of the method 1100 may be performed by a computing device (e.g., a processor, processing circuitry, and / or other suitable components) of a wireless communication device or other suitable means for performing the steps. For example, a wireless communication device (such as BS 105, 205, or 400) may utilize one or more components (such as processor 402, memory 404, channel state module 408, transceiver 410, modem 412, and one or more antennas 416) to perform the steps of method 900. The method 900 may employ the same methods as those described above with reference to FIG. Figure 6-Figure 8 The method 1100 is similar to the mechanism described in sequence 600, scheme 700, and sequence 800. As illustrated, method 1100 includes several enumerated steps, but aspects of method 1100 may include additional steps before, after, and between these enumerated steps. In some aspects, one or more of the enumerated steps may be omitted or performed in a different order.

[0148] At block 1102, the BS 105 may transmit a channel state reporting configuration (e.g., via MAC signaling) to a first UE 115 of the plurality of UEs 115, the channel state reporting configuration indicating a set of one or more measurement resources and at least one of precoding information or a rank indication associated with the set of one or more measurement resources. In some examples, the BS 105 may utilize one or more components, such as the processor 402, the memory 404, the channel state module 408, the transceiver 410, and the modem 412, to perform aspects of block 1102.

[0149] In some aspects, the BS 105 may also indicate the first PMI and the second PMI, and / or the first RI and the second RI. The BS 105 may also transmit a plurality of first reference signals to the first UE 115 at different times within the time period in a first channel response measurement resource that is different from the set of one or more measurement resources. The BS 105 may also transmit to the first UE 115 (e.g., in a channel configuration report) an indication of how much channel state feedback the first UE 115 should provide.

[0150] At block 1104, BS 105 may receive a channel state report from first UE 115, the channel state report including a plurality of expected CQIs within a time period based on the set of one or more measurement resources and at least one of precoding information or a rank indication. In some examples, BS 105 may utilize one or more components, such as processor 402, memory 404, channel state module 408, transceiver 410, and modem 412, to perform aspects of block 1104.

[0151] In some aspects, the channel state report may be based on the multiple first reference signals and may include a first CQI for the first RI and the first PMI, and a second CQI for the second RI (which may be different from the first RI) and the second PMI (which may be different from the first PMI). The first CQI for the first RI and the first PMI and the second CQI for the second RI and the second PMI may be based on the measurement resource set. The channel state report may also include a first MCS for the first RI and a second MCS for the second RI, the first MCS and the second MCS being based on the measurement resource set. The channel state report may also include a CQI history based on the measurement resource set at multiple time moments. The channel state report may also include a history of channel state feedback based on the measurement resource set and at least one of precoding information or rank indication (which may include multiple expected CQIs). Each channel state feedback may be associated with a timestamp.

[0152] At block 1106, BS 105 may also determine link adaptation (e.g., OLLA) for the first UE based at least in part on the channel state report. As part of determining link adaptation, channel state module 408 may determine an update of a precoding matrix indicator (PMI), RI, and / or MCS for the first UE 115. In some examples, BS 105 may utilize one or more components, such as processor 402, memory 404, channel state module 408, transceiver 410, and modem 412, to perform aspects of block 1106.

[0153] Figure 12 1 is a flow chart of a wireless communication method 1200 according to some aspects of the present disclosure. Aspects of the method 1200 may be performed by a computing device (e.g., a processor, processing circuitry, and / or other suitable components) of a wireless communication device or other suitable means for performing the steps. For example, a wireless communication device (such as UE 115, 215, or 500) may utilize one or more components (such as processor 502, memory 504, channel state module 508, transceiver 510, modem 512, and one or more antennas 516) to perform the steps of the method 1200. The method 1200 may employ the same methods as those described above with reference to FIG. Figure 6-Figure 8 The mechanisms described in sequence 600, scheme 700, and sequence 800 are similar. As illustrated, method 1200 includes several enumerated steps, but aspects of method 1200 may include additional steps before, after, and between these enumerated steps. In some aspects, one or more of the enumerated steps may be omitted or performed in a different order.

[0154] At block 1202, UE 115 may receive a channel state reporting configuration from BS 105, the channel state reporting configuration indicating a set of one or more measurement resources and at least one of precoding information or a rank indication associated with the set of one or more measurement resources. In some examples, UE 115 may utilize one or more components, such as processor 502, memory 504, channel state module 508, transceiver 510, and modem 512, to perform aspects of block 1202.

[0155] In some aspects, UE 115 may also receive an indication of a first RI and / or first PMI for which BS 105 desires feedback. UE 115 may also receive an indication of an amount of channel state feedback that UE 115 will transmit to BS 105 as part of the channel feedback history.

[0156] At block 1204, the UE may transmit a channel state report to the BS 105, the channel state report including a plurality of expected CQIs within a time period based on the measurement resource set and at least one of precoding information or rank indication. In some examples, the UE 115 may utilize one or more components, such as the processor 502, the memory 504, the channel state module 508, the transceiver 510, and the modem 512, to perform aspects of block 1204.

[0157] Based on the measurement resource set, the report may include a first CQI for a first RI and a second CQI for a second RI (wherein the first and second RIs are different). Based on the measurement resource set, the report may also include a first CQI for a first PMI and a second CQI for a second PMI (wherein the first and second PMIs are different). Based on the measurement resource set, the report may also include a first MCS for the first RI and a second MCS for the second RI. The report may also include a CQI history based on the measurement resource set at multiple time instants. The report may also include a history of channel state feedback, the history of channel state feedback including multiple expected CQIs based on the measurement resource set and at least one of precoding information or rank indication. In addition, each channel state feedback may be associated with a timestamp.

[0158] UE 115 may also receive scheduling information including PMI, RI, and / or MCS from BS 105 based on the channel state report transmitted by UE 115 .

[0159] Information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0160] The various illustrative blocks and modules described in conjunction with the disclosure herein may be implemented or executed with a general purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0161] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, each function may be stored on or transmitted by a computer-readable medium as one or more instructions or codes. Other examples and implementations fall within the scope of this disclosure and the appended claims. For example, due to the nature of software, the functions described above may be implemented using software executed by a processor, hardware, firmware, hardwiring, or any combination thereof. Features implementing the functions may also be physically located in various locations, including being distributed so that parts of the functions are implemented at different physical locations. In addition, as used herein (including in the claims), "or" used in an enumeration of items (e.g., an enumeration of items with a phrase such as "at least one of" or "one or more of") indicates an inclusive enumeration, such that, for example, an enumeration of [at least one of A, B, or C] means A or B or C or AB or AC or BC or ABC (i.e., A and B and C).

[0162] As will be appreciated by those skilled in the art and depending on the specific application at hand, many modifications, substitutions, and variations can be made in the materials, devices, configurations, and methods of use of the apparatus of the present disclosure without departing from the spirit and scope of the present disclosure. In view of this, the scope of the present disclosure should not be limited to the specific embodiments illustrated and described herein (as these are merely examples of the present disclosure), but should be fully commensurate with the appended claims and their functional equivalents.

Claims

1. A method of wireless communication, comprising: transmitting, by a network entity, a channel state reporting configuration to a first user equipment (UE) among a plurality of UEs, the channel state reporting configuration including a potential precoder list for use by the first UE to estimate interference from other UEs among the plurality of UEs and indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources; transmitting a channel response reference signal to each of the plurality of UEs using a common pilot prior to precoding; receiving, by the network entity, a channel state report from the first UE, the channel state report including interference prediction information based on the channel response reference signal and the channel state report configuration; as well as A determination is made by the network entity based at least in part on the received channel state report to group at least the first and second UEs of the plurality of UEs for multi-user multiple input multiple output (MU-MIMO) scheduling.

2. The method of claim 1 , wherein transmitting one or more channel response reference signals using a common pilot prior to precoding comprises: transmitting a channel response reference signal in a channel response measurement resource different from the set of one or more interference measurement resources; And the method further comprises: refraining, by the network entity, from transmitting a second reference signal in the set of one or more interference measurement resources; Receiving the channel status report includes: The channel state report further based on the channel response reference signal is received by the network entity from the first UE.

3. The method of claim 2 , wherein transmitting the channel response reference signal comprises: A non-zero power channel state information reference signal (NZP-CSI-RS) is transmitted by the network entity to the first UE in the channel response measurement resource.

4. The method of claim 1 , wherein receiving the channel state report comprises: The channel state report including the interference prediction information is received by the network entity from the first UE, wherein the interference prediction information indicates at least one of a rank indicator (RI), a PMI, or an expected channel quality indicator (CQI) associated with the first UE based on a first predicted interference associated with a first interference measurement resource in the set of one or more interference measurement resources and a corresponding first precoding matrix indicator (PMI).

5. The method of claim 4, wherein receiving the channel state report comprises: The channel state report including the interference prediction information is received by the network entity from the first UE, wherein the interference prediction information indicates that the first predicted interference associated with the first interference measurement resource and the corresponding first PMI among the set of one or more interference measurement resources and the corresponding PMI provides a minimum amount of interference to the first UE.

6. The method of claim 1 , wherein transmitting the channel state report configuration comprises: A first precoding matrix indicator (PMI) associated with the first UE and the precoding information are transmitted by the network entity to the first UE, the precoding information including a second PMI associated with a first interference measurement resource in the set of one or more interference measurement resources.

7. The method of claim 6, wherein receiving the channel state report comprises: The channel state report including the interference prediction information is received by the network entity from the first UE, wherein the interference prediction information includes at least one of a rank indicator (RI) or an expected channel quality indicator (CQI) associated with the first UE based on the predicted interference associated with the first interference measurement resource and the second PMI.

8. The method of claim 1 , wherein determining to group at least the first and second UEs among the plurality of UEs for multi-user multiple input multiple output (MU-MIMO) scheduling further comprises: The MU-MIMO scheduling is determined by the network entity based on the received channel state report, the MU-MIMO scheduling including a first precoding matrix indicator (PMI) for the first UE, a first rank indicator (RI) for the first UE, a first modulation and coding scheme (MCS) for the first UE, a second PMI for the second UE, a second RI for the second UE, or at least one of a second MCS for the second UE.

9. The method of claim 1, wherein: Transmitting the channel state report configuration includes: transmitting, by the network entity, the channel state reporting configuration to the first UE via medium access control (MAC) signaling; and Receiving the channel state report includes: The channel state report is received by the network entity from the first UE via medium access control (MAC) signaling.

10. The method of claim 1 , wherein receiving the channel state report comprises: The channel state report including a timestamp is received by the network entity from the first UE.

11. A method of wireless communication, comprising: Receiving, by a user equipment (UE) from a network entity, a channel state reporting configuration, the channel state reporting configuration including a potential precoder list for the UE to use to estimate interference from other UEs of a plurality of UEs and indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources; receiving a channel response reference signal from the network entity using a common pilot prior to precoding; as well as A channel state report is transmitted by the UE to the network entity, where the channel state report includes interference prediction information based on the channel response reference signal and the channel state report configuration.

12. The method of claim 11 , wherein receiving the channel response reference signal comprises: Receiving, by the UE, a first reference signal from the network entity in a channel measurement resource different from the set of one or more interference measurement resources; The method further comprises: determining, by the UE, a channel response based on the received first reference signal; as well as The interference prediction information is determined by the UE based on the set of one or more interference measurement resources, the precoding information, and the determined channel response.

13. The method of claim 12, wherein receiving the first reference signal comprises: A non-zero power channel state information reference signal (NZP-CSI-RS) is received by the UE from the network entity in the channel measurement resource.

14. The method of claim 11 , wherein transmitting the channel state report comprises: The channel state report including the interference prediction information is transmitted by the UE to the network entity, wherein the interference prediction information indicates at least one of a rank indicator (RI), a PMI, or an expected channel quality indicator (CQI) associated with the UE based on a first predicted interference associated with a first interference measurement resource in the set of one or more interference measurement resources and a corresponding first precoding matrix indicator (PMI).

15. The method of claim 14, wherein transmitting the channel state report comprises: The channel state report including the interference prediction information is transmitted by the UE to the network entity, wherein the interference prediction information indicates that the first predicted interference associated with the first interference measurement resource and the corresponding first PMI among the set of one or more interference measurement resources and the corresponding PMI provides a minimum amount of interference to the UE.

16. The method of claim 15, further comprising: The UE selects the first interference measurement resource from the set of one or more interference measurement resources based on the first predicted interference associated with the first interference measurement resource and the first PMI having less interference to the UE than the second predicted interference associated with the second interference measurement resource and the corresponding second PMI in the set of one or more interference measurement resources.

17. The method of claim 11, wherein receiving the channel state report configuration further comprises: A first precoding matrix indicator (PMI) associated with the UE and the precoding information are received by the UE from the network entity, the precoding information including a second PMI associated with a first interference measurement resource in the set of one or more interference measurement resources.

18. The method of claim 17, wherein transmitting the channel state report comprises: The channel state report including the interference prediction information is transmitted by the UE to the network entity, wherein the interference prediction information includes at least one of a rank indicator (RI) or an expected channel quality indicator (CQI) associated with the UE based on the predicted interference associated with the first interference measurement resource and the second PMI.

19. The method of claim 11, further comprising: Scheduling information based on the received channel state report is received by the UE, the scheduling information including at least one of a precoding matrix indicator (PMI), a rank indicator (RI), or a modulation and coding scheme (MCS).

20. The method of claim 11, wherein Receiving the channel state report configuration includes: Receiving, by the UE, the channel state report configuration from the network entity via medium access control (MAC) signaling; and Transmitting the channel state report includes: The channel state report is transmitted by the UE to the network entity via medium access control (MAC) signaling.

21. The method of claim 11, wherein transmitting the channel state report comprises: The channel state report including a timestamp is transmitted by the UE to the network entity.

22. A network entity comprising: A transceiver configured to: transmitting a channel state reporting configuration to a first UE among a plurality of user equipments (UEs), the channel state reporting configuration including a potential precoder list for the first UE to use to estimate interference from other UEs among the plurality of UEs and indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources; transmitting a channel response reference signal to each of the plurality of UEs using a common pilot prior to precoding; receiving a channel state report from the first UE, the channel state report including interference prediction information based on the channel response reference signal and the channel state reporting configuration; as well as A processor configured to: A determination is made based at least in part on the received channel state report to group at least the first and second UEs of the plurality of UEs for multi-user multiple input multiple output (MU-MIMO) scheduling.

23. The network entity of claim 22, wherein: The transceiver configured to transmit one or more channel response reference signals using a common pilot prior to precoding is further configured to: transmitting a channel response reference signal in a channel response measurement resource different from the set of one or more interference measurement resources; and the transceiver is further configured to: refraining from transmitting a second reference signal in the set of one or more interference measurement resources; and The transceiver configured to receive the channel state report is further configured to: The channel state report further based on the channel response reference signal is received from the first UE.

24. The network entity of claim 23, wherein the transceiver configured to transmit the channel response reference signal is further configured to: A non-zero power channel state information reference signal (NZP-CSI-RS) is transmitted to the first UE in the channel response measurement resource.

25. The network entity of claim 22, wherein The transceiver configured to receive the channel state report is further configured to: The channel state report including the interference prediction information is received from the first UE, wherein the interference prediction information indicates at least one of a rank indicator (RI), a PMI, and / or an expected channel quality indicator (CQI) associated with the first UE based on a first predicted interference associated with a first interference measurement resource in the set of one or more interference measurement resources and a corresponding first precoding matrix indicator (PMI).

26. The network entity of claim 25, wherein the transceiver configured to receive the channel state report is further configured to: The channel state report including the interference prediction information is received from the first UE, wherein the interference prediction information indicates that the first predicted interference associated with the first interference measurement resource and the corresponding first PMI among the set of one or more interference measurement resources and the corresponding PMI provides a minimum amount of interference to the first UE.

27. The network entity of claim 22, wherein the transceiver configured to transmit the channel state report configuration is further configured to: A first precoding matrix indicator (PMI) associated with the first UE and the precoding information are transmitted to the first UE, the precoding information including a second PMI associated with a first interference measurement resource in the set of one or more interference measurement resources.

28. The network entity of claim 27, wherein the transceiver configured to receive the channel state report is further configured to: The channel state report including the interference prediction information is received from the first UE, wherein the interference prediction information includes at least one of a rank indicator (RI) or an expected channel quality indicator (CQI) associated with the first UE based on the predicted interference associated with the first interference measurement resource and the second PMI.

29. The network entity of claim 22 , wherein the processor configured to determine to group at least the first and second UEs of the plurality of UEs for multi-user multiple input multiple output (MU-MIMO) scheduling is further configured to: The MU-MIMO scheduling is determined based on the received channel state report, and the MU-MIMO scheduling includes at least one of a first precoding matrix indicator (PMI) for the first UE, a first rank indicator (RI) for the first UE, a first modulation and coding scheme (MCS) for the first UE, a second PMI for the second UE, a second RI for the second UE, or a second MCS for the second UE.

30. The network entity of claim 22, wherein: The transceiver configured to transmit the channel state report configuration is further configured to: transmitting the channel state reporting configuration to the first UE via medium access control (MAC) signaling; and The transceiver configured to receive the channel state report is further configured to: The channel state report is received from the first UE via medium access control (MAC) signaling.

31. The network entity of claim 22, wherein the transceiver configured to receive the channel state report is further configured to: The channel state report including a timestamp is received from the first UE.

32. A user equipment (UE), comprising a processor and a transceiver, the transceiver configured to: receiving a channel state reporting configuration from a network entity, the channel state reporting configuration including a potential precoder list for the UE to use to estimate interference from other UEs of a plurality of UEs and indicating a set of one or more interference measurement resources and precoding information associated with the set of one or more interference measurement resources; receiving a channel response reference signal from the network entity using a common pilot before precoding; and A channel state report is transmitted to the network entity, the channel state report including interference prediction information based on the channel response reference signal and the channel state reporting configuration.

33. The UE of claim 32, wherein: The transceiver configured to receive the channel response reference signal is further configured to: receiving a first reference signal from the network entity in a channel measurement resource different from the set of one or more interference measurement resources; and The processor is further configured to: determining a channel response based on the received first reference signal; and The interference prediction information is determined based on the set of one or more interference measurement resources, the precoding information, and the determined channel response.

34. The UE of claim 33 , wherein the transceiver configured to receive the first reference signal is further configured to: A non-zero power channel state information reference signal (NZP-CSI-RS) is received from the network entity in the channel measurement resource.

35. The UE of claim 32, wherein The transceiver configured to transmit the channel state report is further configured to: and transmitting the channel state report including the interference prediction information to the network entity, wherein the interference prediction information indicates at least one of a rank indicator (RI), a precoding matrix indicator (PMI), or an expected channel quality indicator (CQI) associated with the UE based on a first predicted interference associated with a first interference measurement resource in the set of one or more interference measurement resources and a corresponding first precoding matrix indicator (PMI).

36. The UE of claim 35 , wherein the transceiver configured to transmit the channel state report is further configured to: The channel state report including the interference prediction information is transmitted to the network entity, wherein the interference prediction information indicates that the first predicted interference associated with the first interference measurement resource and the corresponding first PMI among the set of one or more interference measurement resources and the corresponding PMI provides a minimum amount of interference to the UE.

37. The UE of claim 36, wherein the processor is further configured to: The first interference measurement resource is selected from the set of one or more interference measurement resources based on that the first predicted interference associated with the first interference measurement resource and the first PMI has less interference to the UE than the second predicted interference associated with the second interference measurement resource and the corresponding second PMI in the set of one or more interference measurement resources.

38. The UE of claim 32, wherein the transceiver configured to receive the channel state report configuration is further configured to: A first precoding matrix indicator (PMI) associated with the UE and the precoding information are received from the network entity, the precoding information including a second PMI associated with a first interference measurement resource in the set of one or more interference measurement resources.

39. The UE of claim 38, wherein the transceiver configured to transmit the channel state report is further configured to: and transmitting the channel state report including the interference prediction information to the network entity, the interference prediction information including at least one of a rank indicator (RI) or an expected channel quality indicator (CQI) associated with the UE based on the predicted interference associated with the first interference measurement resource and the second PMI.

40. The UE of claim 32, wherein the transceiver is further configured to: Scheduling information based on the received channel state report is received, the scheduling information comprising at least one of a precoding matrix indicator (PMI), a rank indicator (RI), or a modulation and coding scheme (MCS).

41. The UE of claim 32, wherein The transceiver configured to receive the channel state reporting configuration is further configured to: receiving the channel state reporting configuration from the network entity via medium access control (MAC) signaling; and The transceiver configured to transmit the channel state report is further configured to: The channel state report is transmitted to the network entity via medium access control (MAC) signaling.

42. The UE of claim 32, wherein the transceiver configured to transmit the channel state report is further configured to: The channel state report including a timestamp is transmitted to the network entity.

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