Method, user equipment and network node for wireless communication

Abstract

An aspect of the disclosure can provide a method for wireless communication. A UE can receive a CSI configuration from a network node. The UE can perform a CSI measurement based on the CSI configuration. The UE can determine assistance information based on the CSI measurement, where the assistance information can include a periodicity of a next CSI configuration from the network node. The UE can transmit the assistance information to the network node. By utilizing the disclosure, wireless communication can be better performed.

Description

Technical Field

[0001] This invention relates to wireless communication, and more particularly to assistance information and CSI reporting for Channel State Information (CSI). Background Technology

[0002] Wireless communication networks have grown exponentially over the years. Long-Term Evolution (LTE) systems can offer high peak data rates, low latency, higher system capacity, and lower operating costs due to a simplified network architecture. LTE systems (also known as 4G systems) also provide seamless integration with legacy wireless networks such as the Global System for Mobile Communications (GSM), Code Division Multiple Access (CDMA), and Universal Mobile Telecommunications System (UMTS). In LTE systems, the Evolved Universal Terrestrial Radio Access Network (E-UTRAN) consists of multiple evolved Node-Bs (eNodeBs or eNBs) communicating with multiple mobile stations (called User Equipment (UEs)). The 3rd Generation Partnership Project (3GPP) rd Generation Partner Project (3GPP) networks typically include a mix of 2G / 3G / 4G systems. The Next Generation Mobile Network (NGMN) committee has decided to focus future NGMN activities on defining the end-to-end requirements for 5G New Radio (NR) systems (5G System, 5GS).

[0003] In traditional 5G technology, the periodicity of periodic and semi-persistent CSI measurements and reporting is determined and configured by the gNB. Because of the significant uplink (UL) signaling overhead and the unavoidable compression loss due to discretization, obtaining complete channel information is challenging for the gNB.

[0004] Furthermore, in traditional 5G technology, the UE can better understand which configuration is more suitable for the current channel conditions based on CSI measurement results. For example, if the channel changes faster than the current configuration can tolerate, more frequent CSI measurements and reports are needed to avoid performance degradation. Conversely, if the channel changes slower than the current configuration can support, less frequent CSI measurements and reports can help save signaling overhead. Therefore, since the UE can better understand which configuration is more suitable for the current channel conditions, how the UE can assist the gNB in ​​determining the appropriate CSI configuration is worth discussing. Summary of the Invention

[0005] This invention proposes an apparatus and method for auxiliary information transmission and CSI reporting. A network node can assign a CSI configuration to a UE and send the CSI configuration to the UE. The UE can perform CSI measurements based on the CSI configuration from the network node, determine auxiliary information based on the CSI measurement results, and send the auxiliary information to the network node to improve downlink throughput and save signaling overhead for CSI measurement or CSI reporting.

[0006] A method for wireless communication includes: a user equipment receiving channel state information configuration from a network node; the user equipment performing channel state information measurement based on the channel state information configuration; the user equipment determining auxiliary information based on the channel state information measurement, wherein the auxiliary information includes a period of the next channel state information configuration from the network node; and the user equipment sending the auxiliary information to the network node.

[0007] A method for wireless communication includes: a network node configuring a channel state information report to a user equipment with a first periodic value and a second periodic value, wherein the first periodic value corresponds to a normal mode and the second periodic value corresponds to an aggressive mode, wherein the first periodic value is greater than the second periodic value; and the network node receiving a channel state information report from the user equipment based on the normal mode or the aggressive mode.

[0008] A method for wireless communication includes: a user equipment sending a scheduling request to a network node, the scheduling request indicating a first period value and a second period value configured for a channel state information report, wherein the first period value corresponds to a normal mode and the second period value corresponds to an aggressive mode, wherein the first period value is greater than the second period value; and the user equipment sending a channel state information report to the network node based on the normal mode or the aggressive mode.

[0009] By utilizing this invention, wireless communication can be improved.

[0010] Other embodiments and advantages will be described in the detailed description below. This invention is not intended to be defined. The invention is defined by the claims. Attached Figure Description

[0011] The accompanying drawings illustrate embodiments of the invention, wherein the same numbers may represent the same components.

[0012] Figure 1 This is a simplified block diagram of network nodes and user equipment implementing some embodiments of the present invention.

[0013] Figure 2A This is a schematic diagram based on a novel aspect of differential CSI reporting.

[0014] Figure 2B This is a schematic diagram based on another novel aspect of the differential CSI report.

[0015] Figure 3A This is a diagram based on a subset of CSI reporting, which is a novel aspect.

[0016] Figure 3B This is a schematic diagram based on a subset of CSI reports from another novel aspect.

[0017] Figure 4A This is a schematic diagram based on a novel aspect of the CSI confidence indicator.

[0018] Figure 4B This is a schematic diagram of the CSI confidence indicator based on another novel aspect.

[0019] Figure 5 It is a flowchart based on a novel aspect of an auxiliary information transmission method.

[0020] Figure 6 This is a flowchart based on a novel aspect of CSI reporting methodology.

[0021] Figure 7 This is a flowchart based on another novel aspect of the CSI reporting methodology. Detailed Implementation

[0022] The present invention will now be described in detail with reference to some embodiments thereof, examples of which are illustrated in the accompanying drawings.

[0023] Figure 1This is a simplified block diagram of a network node and a UE implementing some embodiments of the present invention. Network node 101 may be a base station (BS) or gNB, but the invention is not limited thereto. UE 102 may be a smartphone, wearable device, Internet of Things (IoT) device, tablet computer, etc. Alternatively, UE 102 may be a laptop or personal computer (PC) with a data card inserted or installed, wherein the data card may include a modem and a radio frequency (RF) transceiver to provide wireless communication capabilities.

[0024] Network node 101 may have an antenna array 111, which may have multiple antenna elements for transmitting and receiving radio signals. One or more RF transceiver modules 112 coupled to the antenna array 111 may receive RF signals from the antenna array 111, convert the RF signals into baseband signals, and send the baseband signals to processor 113. The RF transceiver 112 may also convert the baseband signals received from processor 113 into RF signals and transmit them through the antenna array 111. Processor 113 may process the received baseband signals and invoke different functional modules 120 to execute the features of network node 101. Storage medium 114 may store program instructions and data 115 to control the operation of network node 101. Network node 101 may also include multiple functional modules for performing different tasks according to embodiments of the present invention.

[0025] Similarly, UE 102 may have an antenna array 131 for transmitting and receiving radio signals. An RF transceiver 132 coupled to the antenna can receive RF signals from the antenna array 131, convert the RF signals into baseband signals, and transmit the baseband signals to the processor 133. The RF transceiver 132 can also convert baseband signals received from the processor 133 into RF signals and transmit them to the antenna array 131. The processor 133 can process the received baseband signals and invoke different functional modules 140 to execute features in UE 102. Storage medium 134 can store program instructions and data 135 to control the operation of UE 102. UE 102 may also include multiple functional modules and circuits to perform different tasks according to embodiments of the present invention.

[0026] The aforementioned functional modules and circuits 120 and 140 can be implemented and configured by hardware, firmware, software, or any combination thereof. When executed by processors 113 and 133 (e.g., by executing program code 115 and 135), the aforementioned functional modules and circuits 120 and 140 can allow network node 101 and UE 102 to execute embodiments of the present invention.

[0027] exist Figure 1 In the example, network node 101 may include resource allocation circuitry 121 and configuration circuitry 122. Resource allocation circuitry 121 may allocate CSI configuration to UE 102. Configuration circuitry 122 may send CSI configuration to UE 102.

[0028] exist Figure 1 In the example, UE 102 may include a CSI measurement circuit 141, a determination circuit 142, and a reporting circuit 143. The CSI measurement circuit 141 may perform CSI measurements based on CSI configurations from network node 101. The determination circuit 142 may determine auxiliary information and a CSI report based on the CSI measurement results from the CSI measurement circuit 141. The reporting circuit 143 may send the auxiliary information and the CSI report to network node 101.

[0029] According to a novel aspect, UE 102 can receive CSI configuration from network node 101. The CSI configuration may include a CSI-Reference Signal (CSI-RS), wherein the CSI-RS may be periodic or semi-persistent. In one embodiment, the CSI-RS may be configured for channel measurement. In another embodiment, the CSI-RS may be configured for interference measurement. Furthermore, in one embodiment, the CSI-RS may be a CSI-Interference Measurement (CSI-IM) for measuring inter-cell interference.

[0030] UE 102 can perform CSI measurements based on the CSI configuration from network node 101. Then, UE 102 can determine auxiliary information based on the results of the CSI measurements. UE 102 can send the auxiliary information to network node 101. In one embodiment, UE 102 can send the auxiliary information to network node 101 via a Medium Access Control-Control Element (MAC-CE) on the Physical Uplink Shared Channel (PUSCH). In one embodiment, network node 101 can determine restrictions to limit the number of times auxiliary information is sent or to limit the duration of auxiliary information transmission. These restrictions can be configured by network 101 for UE 102 or pre-set in UE 102. UE 102 can limit the number of times auxiliary information is sent or the duration of auxiliary information transmission based on the restrictions from network 101. In one example, the restrictions can indicate that a limited number of MAC-CEs can be sent within a time period. In another example, the constraint could instruct that once UE 102 has sent a MAC-CE with auxiliary information to network node 101, UE 102 cannot send another or a subsequent MAC-CE with auxiliary information to network node 101 for a certain period of time. In another embodiment, UE 102 can be configured with a timer. The timer can be enabled when UE 102 sends a MAC-CE with auxiliary information to network node 101. UE 102 cannot send another or a subsequent MAC-CE with auxiliary information to network node 101 before the timer expires.

[0031] According to a novel aspect, the auxiliary information may include the period of the next CSI configuration from network node 101. In one example, UE 102 may notify network node 101 of the desired periodicity of the CSI-RS for channel measurements or the desired periodicity of the CSI-RS for interference measurements, and network node 101 may send the next CSI-RS based on the period notified by UE 102. The desired periodicity of the CSI-RS for channel measurements and the desired periodicity of the CSI-RS for interference measurements may be the same or different. In one embodiment, network 101 may pre-configure a list for UE 102, and UE 102 may determine its desired periodicity from the list. For example, the list may include {4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 160, 320, 640} (time slots), and UE 102 may select the desired periodicity from the list. In another embodiment, network 101 may pre-configure a bitmap for UE 102, and UE 102 may determine its desired period from the bitmap. For example, the bitmap may include four codepoints 0, 1, 2, and 3, where codepoint "0" indicates a period length of less than 10 time slots, codepoint "1" indicates a period length of 10 time slots, codepoint "2" indicates a period length of 20 time slots, and codepoint "3" indicates a period length of more than 20 time slots. UE 102 may determine its desired period based on the bitmap.

[0032] According to a novel aspect, the auxiliary information may also include at least one of the following: Doppler information, bandwidth configuration, delay information, and the frequency of CSI reports.

[0033] Doppler information may include average Doppler shift, maximum Doppler shift, or Doppler spread. Network node 101 can determine whether to update the cycle based on the Doppler information from UE 102.

[0034] The bandwidth configuration can indicate whether the desired bandwidth configuration of UE 102 is wideband or subband. Furthermore, the bandwidth configuration may also include the subband size. In one embodiment, network 101 may pre-configure a list for UE 102, and UE 102 can determine its desired bandwidth configuration from that list. In another embodiment, network 101 may pre-configure a bitmap for UE 102, and UE 102 can determine its desired bandwidth configuration from that bitmap.

[0035] Latency information may include average latency offset, maximum latency offset, or latency spread. Network node 101 can determine whether to update the bandwidth configuration based on the latency information from UE 102.

[0036] According to a novel aspect, UE 102 may send a scheduling request to network node 101 on the Physical Uplink Control Channel (PUCCH) to request aperiodic CSI measurements or aperiodic CSI reports. In one example, the scheduling request for aperiodic CSI measurements may include at least one of the duration and interval of an aperiodic CSI-RS resource burst. In one embodiment, UE 102 may also send a scheduling request to network node 101 to request a change in the period or reporting configuration of the CSI resource for a short period of time.

[0037] In one embodiment, in an event where the average signal-to-interference-plus-noise ratio (SINR) of the Doppler spectrum at the boundary is greater than a threshold, UE 102 may send a scheduling request to network node 101 requesting an aperiodic CSI measurement. For example, when X% of the Doppler spectrum is located at the boundary and the average SINR of the X% Doppler spectrum at the boundary is greater than the threshold, UE 102 may send a scheduling request to network 101 requesting an aperiodic CSI measurement, where X and the threshold may be predetermined in UE 102 or configured by network node 101.

[0038] In another embodiment, in an event where updating the CSI can gain or increase more than a portion of the throughput, UE 102 may send a scheduling request to network node 101 requesting an aperiodic CSI report. For example, when updating the CSI can gain more than X% of the throughput, UE 102 may send a scheduling request to network node 101 requesting an aperiodic CSI report to update the CSI, where X can be predetermined in UE 102 or configured by network node 101.

[0039] According to a novel aspect, network node 101 can configure a first period value and a second period value for CSI report configuration to UE 102. Network node 101 can receive CSI reports from UE 102 based on normal mode or aggressive mode. The first period value can correspond to normal mode, the second period value can correspond to aggressive mode, and the first period value can be greater than the second period value.

[0040] According to another novel aspect, UE 102 can send a scheduling request to the network node to indicate a first period value and a second period value for CSI report configuration. UE 102 can then send a CSI report to network node 101 based on either a normal mode or an aggressive mode. The first period value may correspond to the normal mode, the second period value may correspond to the aggressive mode, and the first period value may be greater than the second period value.

[0041] In this invention, the normal mode means that network node 101 can receive a CSI report with complete information (e.g., all information or all parameters) from UE 102 based on a first period value, or UE 102 can send a CSI report with complete information (e.g., all information or all parameters) to network node 101 based on the first period value. The aggressive mode means that network node 101 can receive a CSI report with partial information (e.g., difference information or partial parameters) from UE 102 based on a second period value, or UE 102 can send a CSI report with partial information (e.g., difference information or partial parameters) to network node 101 based on the second period value.

[0042] In one embodiment, UE 102 can send a CSI report with complete information in normal mode and a CSI report with differential information between the CSI report and a previous CSI report in aggressive mode. The differential information can refer to the difference between the CSI report and the previous CSI report. Figure 2A For example, UE 102 can send CSI reports with complete information (such as CSI1 and CSI5) every four time units (i.e., the first cycle value is four time units). Otherwise, UE 102 may send CSI reports with differential information (e.g., CSI2 with differential information Δ2, CSI3 with differential information Δ3, CSI4 with differential information Δ4, CSI6 with differential information Δ6, CSI7 with differential information Δ7, and CSI8 with differential information Δ8) every time unit (i.e., the second period value is one time unit). Here, differential information Δ2 can represent the difference between CSI reports CSI1 and CSI2, differential information Δ3 can represent the difference between CSI reports CSI2 and CSI3, differential information Δ4 can represent the difference between CSI reports CSI3 and CSI4, differential information Δ6 can represent the difference between CSI reports CSI5 and CSI6, differential information Δ7 can represent the difference between CSI reports CSI6 and CSI7, and differential information Δ8 can represent the difference between CSI reports CSI7 and CSI8.

[0043] In another embodiment, UE 102 can send a CSI report with all parameters in normal mode and a CSI report with partial parameters in aggressive mode. For example, each CSI report may include the following parameters: CSI-RS Resource Indicator (CRI), Rank Indicator (RI), Precoding Matrix Indicator (PMI), and Channel Quality Indicator (CQI). When UE 102 only needs to send a CSI report with partial parameters, UE 102 can send a CSI report including only the CQI. Figure 3A For example, UE 102 can send a CSI report with all parameters every four time units (i.e., the first period is four time units). This could be CSI1 (including CRI1, RI1, PMI1, and CQI1) and CSI5 (including CRI5, RI5, PMI5, and CQI5). Alternatively, UE 102 can send a CSI report with only some parameters every time unit (i.e., the second period is one time unit). This could be CSI2 (including only CQI2), CSI3 (including only CQI3), CSI4 (including only CQI4), CSI6 (including only CQI6), CSI7 (including only CQI7), and CSI8 (including only CQI8).

[0044] According to a novel aspect, network node 101 can configure UE 102 to send CSI reports with complete information (e.g., all information or all parameters) aperiodically. When network node 101 does not trigger a CSI report with complete information, UE 102 can send a CSI report with partial information (e.g., differential information or partial parameters) to network node 101.

[0045] According to another novel aspect, UE 102 can send scheduling requests aperiodically, which can indicate whether to send a CSI report with complete information (e.g., all information or all parameters). When UE 102 does not indicate a CSI report with complete information, UE 102 can send a CSI report with partial information (e.g., differential information or partial parameters) to network node 101.

[0046] In one embodiment, UE 102 can send a non-periodic CSI report with differential information based on the latest CSI report. Figure 2BFor example, UE 102 can send CSI report CSI1 with complete information, CSI report CSI4 with complete information, and CSI report CSI6 with complete information. Furthermore, UE 102 can send CSI report CSI2 with differential information Δ2 based on CSI report CSI1, CSI report CSI3 with differential information Δ3 based on CSI report CSI2, and CSI report CSI5 with differential information Δ5 based on CSI report CSI4.

[0047] In one embodiment, UE 102 can send a non-periodic CSI report with partial parameters based on the latest CSI report. Figure 3B For example, UE 102 can send CSI report CSI1, which includes CRI1, RI1, PMI1, and CQI1, and CSI report CSI5, which includes CRI5, RI5, PMI5, and CQI5. Additionally, UE 102 can send CSI report CSI3, which only includes CQI3, based on CSI report CSI1, and UE 102 can send CSI report CSI6, which only includes CQI6, based on CSI report CSI5.

[0048] Accordingly, in this invention, when the CSI changes smoothly over time, the UE 102 can flexibly send CSI reports without having to send all CSI reports with complete information.

[0049] According to a novel aspect, network node 101 can receive a CSI report with a CSI confidence indicator from UE 102.

[0050] In one embodiment, the CSI confidence indicator may include a bit, wherein in an event where the bit is a first value, the CSI confidence indicator may indicate that the CSI report is confident, and in another event where the bit is a second value, the CSI confidence indicator may indicate that the CSI report is unreliable. UE 102 may determine the CSI confidence indicator based on a bitmap. Figure 4A For example, when the bit of the CSI confidence indicator is "0", the CSI confidence indicator can indicate that the CSI report is credible, and when the bit of the CSI confidence indicator is "1", the CSI confidence indicator can indicate that the CSI report is not credible.

[0051] In another embodiment, the CSI confidence indicator may include a bit selected by the UE 102 from a plurality of bits, where each bit may correspond to a corresponding confidence level. The UE 102 may determine the CSI confidence indicator based on a bitmap. Figure 4BFor example, when the bit of the CSI confidence indicator is "0", the CSI confidence indicator can represent a confidence level of "0"; when the bit of the CSI confidence indicator is "1", the CSI confidence indicator can represent a confidence level of "1"; when the bit of the CSI confidence indicator is "2", the CSI confidence indicator can represent a confidence level of "2"; and when the bit of the CSI confidence indicator is "3", the CSI confidence indicator can represent a confidence level of "3".

[0052] Figure 5 This is a flowchart of an auxiliary information transmission method according to a novel aspect. In step 501, UE 102 can receive CSI configuration from network node 101.

[0053] In step 502, UE 102 can perform CSI measurements based on the CSI configuration.

[0054] In step 503, UE 102 may determine auxiliary information based on CSI measurements, wherein the auxiliary information may include the period of the next CSI configuration from network node 101.

[0055] In step 504, UE102 can send auxiliary information to network node 101.

[0056] In the auxiliary information transmission method, auxiliary information can be sent to network nodes via MAC-CE on the PUSCH.

[0057] In the auxiliary information transmission method, the auxiliary information may also include at least one of Doppler information, bandwidth configuration, delay information, and CSI reporting frequency.

[0058] Figure 6 This is a flowchart of a novel CSI reporting method. In step 601, network node 101 may configure a first period value and a second period value for CSI reporting configuration to UE 102, wherein the first period value may correspond to a normal mode, the second period value may correspond to an aggressive mode, and the first period value may be greater than the second period value.

[0059] In step 602, network node 101 may receive CSI reports from UE based on normal mode or aggressive mode.

[0060] Figure 7 This is a flowchart of a CSI reporting method according to another novel aspect. In step 701, UE 102 may send a scheduling request to network node 101, which may indicate a first period value and a second period value of the CSI reporting configuration, wherein the first period value may correspond to the normal mode and the second period value may correspond to the aggressive mode, and the first period value may be greater than the second period value.

[0061] In step 702, UE 102 may send a CSI report to network node 101 based on normal mode or aggressive mode.

[0062] While the present invention has been disclosed above with reference to specific embodiments for guidance purposes, the invention is not limited thereto. Accordingly, various modifications, adjustments, and combinations can be made to the various features of the above embodiments without departing from the scope set forth in the claims of the present invention.

Claims

1. A method for wireless communication, comprising: The user equipment receives channel state information from the network node for configuration. The user equipment is configured to perform channel state information measurement based on the channel state information; The user equipment determines auxiliary information based on the channel state information measurement, wherein the auxiliary information includes the period of the next channel state information configuration from the network node, and the user equipment determines the period from the list configured by the network node; as well as The user equipment sends the auxiliary information to the network node.

2. The method for wireless communication as described in claim 1, characterized in that, The sending includes: The auxiliary information is sent to the network node via the control unit of Media Access Control on the physical uplink shared channel.

3. The method for wireless communication as described in claim 1, characterized in that, Also includes: The user equipment receives restrictions from the network node to limit the number of times the auxiliary information is sent or to limit the duration of sending the auxiliary information.

4. The method for wireless communication as described in claim 1, characterized in that, The channel state information configuration includes a channel state information reference signal, wherein the channel state information reference signal is periodic or semi-persistent.

5. The method for wireless communication as described in claim 4, characterized in that, The channel state information reference signal is used for channel measurement or interference measurement.

6. The method for wireless communication as described in claim 4, characterized in that, The channel state information reference signal is a channel state information interference measurement.

7. The method for wireless communication as described in claim 1, characterized in that, The auxiliary information also includes at least one of the following: The frequency of reporting Doppler information, bandwidth configuration, delay information, and channel state information.

8. The method for wireless communication as described in claim 1, characterized in that, Also includes: The user equipment sends a scheduling request to the network node on the physical uplink control channel to request aperiodic channel state information measurement or aperiodic channel state information report.

9. The method for wireless communication as described in claim 8, characterized in that, In an event where the average signal-to-interference-plus-noise ratio of the Doppler spectrum at the boundary is greater than a threshold, the user equipment sends the scheduling request for the aperiodic channel state information measurement.

10. The method for wireless communication as described in claim 8, characterized in that, In an event where more than a portion of the throughput can be obtained by updating the channel state information, the user equipment sends the scheduling request for the aperiodic channel state information report.

11. The method for wireless communication as described in claim 8, characterized in that, The scheduling request for the aperiodic channel state information measurement includes at least one of the duration and interval of the aperiodic channel state information reference signal resource burst.

12. A user equipment for wireless communication, comprising: A processor, when executing program instructions stored in a storage medium, performs the steps of the method for wireless communication as described in any one of claims 1-11.

13. A storage medium storing program instructions that, when executed by a user equipment, cause the user equipment to perform the steps of the method for wireless communication according to any one of claims 1-11.

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