THREE BIT SUB-BAND CHANNEL QUALITY INDICATOR FEEDBACK

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a mobile station may select a sub-band differential channel quality indicator (CQI) value from a plurality of sub-band differential CQI values based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets. In some aspects, a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points. The mobile station may transmit an indication of the selected sub-band differential CQI value. Numerous other aspects are described.

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for three bit sub-band channel quality indicator (CQI) feedback.

BACKGROUND

SUMMARY

Some aspects described herein relate to a method of wireless communication performed by a mobile station. The method may include selecting, by the mobile station, a sub-band differential channel quality indicator (CQI) value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, where a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points. The method may include transmitting, by the mobile station, an indication of the selected sub-band differential CQI value.

Some aspects described herein relate to a method of wireless communication performed by a mobile station. The method may include selecting, by the mobile station, a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, where a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets, or where a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets. The method may include transmitting, by the mobile station, an indication of the selected sub-band differential CQI value.

Some aspects described herein relate to a method of wireless communication performed by a mobile station. The method may include determining, by a mobile station, whether a set of uplink resources to be used for transmitting a channel state information (CSI) communication is sufficient to permit a three bit sub-band differential CQI value to be transmitted in the CSI communication. The method may include selectively transmitting, by the mobile station, the three bit sub-band differential CQI value in the CSI communication based at least in part on the determination of whether the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

Some aspects described herein relate to a mobile station for wireless communication. The mobile station may include a memory and one or more processors coupled to the memory. The one or more processors may be configured to select a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, where a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points. The one or more processors may be configured to transmit an indication of the selected sub-band differential CQI value.

Some aspects described herein relate to a mobile station for wireless communication. The mobile station may include a memory and one or more processors coupled to the memory. The one or more processors may be configured to select a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, where a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets, or where a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets. The one or more processors may be configured to transmit an indication of the selected sub-band differential CQI value.

Some aspects described herein relate to a mobile station for wireless communication. The mobile station may include a memory and one or more processors coupled to the memory. The one or more processors may be configured to determine whether a set of uplink resources to be used for transmitting a CSI communication is sufficient to permit a three bit sub-band differential CQI value to be transmitted in the CSI communication. The one or more processors may be configured to selectively transmit the three bit sub-band differential CQI value in the CSI communication based at least in part on the determination of whether the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a mobile station. The set of instructions, when executed by one or more processors of the mobile station, may cause the mobile station to select a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, where a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points. The set of instructions, when executed by one or more processors of the mobile station, may cause the mobile station to transmit an indication of the selected sub-band differential CQI value.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a mobile station. The set of instructions, when executed by one or more processors of the mobile station, may cause the mobile station to select a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, where a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets, or where a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets. The set of instructions, when executed by one or more processors of the mobile station, may cause the mobile station to transmit an indication of the selected sub-band differential CQI value.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a mobile station. The set of instructions, when executed by one or more processors of the mobile station, may cause the mobile station to determine whether a set of uplink resources to be used for transmitting a CSI communication is sufficient to permit a three bit sub-band differential CQI value to be transmitted in the CSI communication. The set of instructions, when executed by one or more processors of the mobile station, may cause the mobile station to selectively transmit the three bit sub-band differential CQI value in the CSI communication based at least in part on the determination of whether the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for selecting a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, where a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points. The apparatus may include means for transmitting an indication of the selected sub-band differential CQI value.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for selecting a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, where a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets, or where a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets. The apparatus may include means for transmitting an indication of the selected sub-band differential CQI value.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for determining whether a set of uplink resources to be used for transmitting a CSI communication is sufficient to permit a three bit sub-band differential CQI value to be transmitted in the CSI communication. The apparatus may include means for selectively transmitting the three bit sub-band differential CQI value in the CSI communication based at least in part on the determination of whether the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

DETAILED DESCRIPTION

FIG.1is a diagram illustrating an example of a wireless network100, in accordance with the present disclosure. The wireless network100may be or may include elements of a 5G (e.g., NR) network and/or a 4G (e.g., Long Term Evolution (LTE)) network, among other examples. The wireless network100may include one or more base stations110(shown as a BS110a,a BS110b,a BS110c,and a BS110d), a user equipment (UE)120or multiple UEs120(shown as a UE120a,a UE120b,a UE120c,a UE120d,and a UE120e), and/or other network entities. A base station110is an entity that communicates with UEs120. A base station110(sometimes referred to as a BS) may include, for example, an NR base station, an LTE base station, a Node B, an eNB (e.g., in 4G), a gNB (e.g., in 5G), an access point, and/or a transmission reception point (TRP). Each base station110may provide communication coverage for a particular geographic area. In the Third Generation Partnership Project (3GPP), the term “cell” can refer to a coverage area of a base station110and/or a base station subsystem serving this coverage area, depending on the context in which the term is used.

In some aspects, a mobile station (e.g., a UE120) may include a communication manager140. As described in more detail elsewhere herein, the communication manager140may select a sub-band differential channel quality indicator (CQI) value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, wherein a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points; and transmit an indication of the selected sub-band differential CQI value. Additionally, or alternatively, the communication manager140may perform one or more other operations described herein.

In some aspects, a mobile station (e.g., a UE120) may include a communication manager140. As described in more detail elsewhere herein, the communication manager140may select a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, wherein a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets, or wherein a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets; and transmit an indication of the selected sub-band differential CQI value. Additionally, or alternatively, the communication manager140may perform one or more other operations described herein.

In some aspects, a mobile station (e.g., a UE120) may include a communication manager140. As described in more detail elsewhere herein, the communication manager140may determine whether a set of uplink resources to be used for transmitting a CSI communication is sufficient to permit a three bit sub-band differential CQI value to be transmitted in the CSI communication; and selectively transmit the three bit sub-band differential CQI value in the CSI communication based at least in part on the determination of whether the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication. Additionally, or alternatively, the communication manager140may perform one or more other operations described herein.

FIG.2is a diagram illustrating an example200of a base station110in communication with a UE120in a wireless network100, in accordance with the present disclosure. The base station110may be equipped with a set of antennas234athrough234t,such as T antennas (T≥1). The UE120may be equipped with a set of antennas252athrough252r,such as R antennas (R≥1).

In some aspects, a mobile station (e.g., a UE120) includes means for selecting a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, wherein a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points; and/or means for transmitting an indication of the selected sub-band differential CQI value. In some aspects, the means for the mobile station to perform operations described herein may include, for example, one or more of communication manager140, antenna252, modem254, MIMO detector256, receive processor258, transmit processor264, TX MIMO processor266, controller/processor280, or memory282.

In some aspects, a mobile station (e.g., a UE12) includes means for selecting a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, wherein a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets, or wherein a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets; and/or means for transmitting an indication of the selected sub-band differential CQI value. In some aspects, the means for the mobile station to perform operations described herein may include, for example, one or more of communication manager140, antenna252, modem254, MIMO detector256, receive processor258, transmit processor264, TX MIMO processor266, controller/processor280, or memory282.

In some aspects, a mobile station (e.g., a UE120) includes means for determining whether a set of uplink resources to be used for transmitting a CSI communication is sufficient to permit a three bit sub-band differential CQI value to be transmitted in the CSI communication; and/or means for selectively transmitting the three bit sub-band differential CQI value in the CSI communication based at least in part on the determination of whether the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication. In some aspects, the means for the mobile station to perform operations described herein may include, for example, one or more of communication manager140, antenna252, modem254, MIMO detector256, receive processor258, transmit processor264, TX MIMO processor266, controller/processor280, or memory282.

A CQI value allows a UE to quantify and report downlink radio channel conditions within a bandwidth part. A CQI value can be reported to a base station using a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH). The CQI value represents a signal to interference plus noise ratio (rather than a signal strength) and is reported based on a CQI table that corresponds to a set of physical downlink shared channel (PDSCH) MCSs (e.g., a 64 quadrature amplitude modulation (QAM) table, a 256 QAM table, and a low spectral efficiency table). In general, a CQI value is signaled using a set of four bits, which enables the CQI value to be in a range of integer values from 0 to 15. A higher CQI value indicates that the UE is able to receive higher order modulation with a high coding rate (i.e., relatively little channel coding redundancy).

In some wireless communication systems, a base station can request a UE to report wideband or sub-band CQI values. A wideband CQI provides a result which is derived from an entire bandwidth part. In contrast, a sub-band CQI provides a result which is derived from a specific section of bandwidth part (i.e., a sub-band of the bandwidth part). A size of sub-bands within a bandwidth part can be indicated by the base station and can also depend on the size of the bandwidth part. In some cases, a bandwidth part can include many sub-bands (e.g., up to 19 sub-bands). In such a case, if an absolute CQI value is signaled for each sub-band, a signaling payload for reporting CQI values may be undesirably large (e.g., since each sub-band CQI value is reported in four bits).

Therefore, in some wireless communication systems, differential CQI values can be used for sub-band CQI reporting. Typically, the differential CQI value is indicated in two bits (rather than four bits) to reduce signaling payload. A differential sub-band CQI value is defined relative to the wideband CQI value using the following expression:

Thus, when the UE is configured to report sub-band CQI feedback, the UE reports a wideband CQI value (used as a reference CQI) and, for each sub-band, the UE reports a difference (i.e., an offset) between a sub-band CQI value and the wideband CQI value. Typically, the difference between the sub-band CQI value and the wideband CQI value is quantized into two bits according to the following table:

As an example, if a difference between a sub-band CQI value and the wideband CQI value is 0 (e.g., sub-band CQI offset=0), then the sub-band CQI offset is quantized to a sub-band differential CQI value of 0. As another example, if a difference between a sub-band CQI value and the wideband CQI value is 5 (e.g., sub-band CQI offset=5), then the sub-band CQI offset is quantized to a sub-band differential CQI value of 2. As another example, if a difference between a sub-band CQI value and the wideband CQI value is −1 (e.g., sub-band CQI offset=−1), then the sub-band CQI offset is quantized to a sub-band differential CQI value of 3.

In some scenarios, however, it may be desirable to permit the sub-band CQI offset to be reported in three bits (rather than two bits). The use of three bits can improve accuracy of CQI feedback which may improve reliability, which may be desirable for some types of service (e.g., an ultra-reliable low-latency communication (URLLC) service), while still reducing payload (e.g., as compared to using four bits). To enable sub-band CQI offsets to be reported in three bits, a set of quantization points (e.g., a quantization table) should be configured to quantize possible sub-band CQI offsets which can range from −15 to 15 (e.g., a range corresponding to maximum possible difference of the sub-band CQI from the wideband CQI).

Some aspects described herein provide techniques and apparatuses for three bit sub-band CQI feedback. In some aspects, a UE may select a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets. In some aspects, a quantity of negative quantization points in the set of quantization points is different than (e.g., greater than or less than) a quantity of positive quantization points in the set of quantization points. In some aspects, a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets. In some aspects, a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets. The UE may then transmit an indication of the selected sub-band differential CQI value (e.g., in a three bit value corresponding to the selected sub-band differential CQI value). Additionally, in some aspects, a UE may determine whether a set of uplink resources to be used for transmitting a CSI communication is sufficient to permit a three bit sub-band differential CQI value to be transmitted in the CSI communication. Here, the UE may selectively transmit the three bit sub-band differential CQI value in the CSI communication based at least in part on the determination. Additional details are provided below.

FIGS.3A and3Bare diagrams illustrating examples associated with three bit sub-band CQI feedback, in accordance with the present disclosure. As shown inFIG.3A, an example300includes communication between a base station110and a UE120. In some aspects, base station110and UE120may be included in a wireless network, such as wireless network100. Base station110and UE120may communicate via a wireless access link, which may include an uplink and a downlink

As shown inFIG.3Aby reference305, a UE120may select a sub-band differential CQI value from a plurality of sub-band differential CQI values. In some aspects, the UE120selects the sub-band differential CQI value based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets. For example, the UE120may determine a wideband CQI value for a bandwidth part and a sub-band CQI value for a given sub-band of the bandwidth part. The UE120may then determine the sub-band CQI offset based on a difference between the sub-band CQI value and the wideband CQI value. Next, the UE120identifies a quantization point for the sub-band CQI offset according to a quantization table (e.g., a table associating each of a set of quantization points for a range of CQI offsets to a respective sub-band differential CQI value), and the UE120selects a sub-band differential CQI value from the quantization table based on the identified quantization point. In some aspects, the quantization table is designed such that each sub-band differential CQI value can be represented by a three bit value (e.g., the quantization table may include up to eight sub-band differential CQI values, each associated with a different quantization point).

In some aspects, a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points. For example, in some aspects, the quantity of negative quantization points in the set of quantization points is greater than the quantity of positive quantization points in the set of quantization points. Put another way, in some aspects, a granularity of quantization points on a negative side of the range of sub-band CQI offsets is finer than a granularity of quantization points on a positive side of the range of sub-band CQI offsets. As a particular example, with reference to the example quantization table shown inFIG.3B, there are four quantization points (e.g., −8, −4, −2, and −1) on the negative side of the range of sub-band CQI offsets (e.g., the range from −15 to 15) and three quantization points (e.g., 1, 2, and 4) on the positive side of the range of sub-band CQI offsets. In some aspects, as illustrated inFIG.3B, at least three quantization points in the set of quantization points are on the negative side of the sub-band CQI offset range.

In some aspects, having more quantization points on the negative side of the range of sub-band CQI offsets improves accuracy of MCS selection performed based at least in part on CQI feedback, thereby improving reliability. As one example, the UE120may determine that a first sub-band has a sub-band CQI offset of −5, and that a second sub-band has a sub-band CQI offset of −10. Here, if the negative side of the range of CQI offsets had quantization points only at −1 and −4, then the UE120would quantize the sub-band CQI offset of the first sub-band to a sub-band differential CQI value of −4, and also would quantize the sub-band CQI offset of the second sub-band to the sub-band differential CQI value of −4. In such a case, the UE120may select an MCS for the first sub-band based on the sub-band differential CQI value of −4, and a transport block scheduled on the first sub-band might be able to be decoded by the UE120(e.g., since the actual sub-band CQI offset was −5). Additionally, the UE120may select an MCS for the second sub-band based on the sub-band differential CQI value of −4, but a transport block scheduled on the second sub-band is likely to fail (e.g., since the actual sub-band CQI offset was −10). In this example, if the set of quantization points also included a quantization point at −8 (in addition to −1 and −4), then the UE120would quantize the sub-band CQI offset of the second sub-band to the sub-band differential CQI value of −8 (rather than −4). In such a scenario, the UE120would select an MCS for the second sub-band based on the sub-band differential CQI value of −8 (rather than −4), and a transport block scheduled on the second sub-band is more likely be able to be decoded by the UE120(e.g., since the actual sub-band CQI offset was −10). In this way, having more quantization points on the negative side of the range of sub-band CQI offsets improves accuracy of MCS selection performed based at least in part on CQI feedback, thereby providing improved reliability.

As another example, in some aspects, the quantity of negative quantization points in the set of quantization points is less than the quantity of positive quantization points in the set of quantization points. Put another way, in some aspects, a granularity of quantization points on a positive side of the range of sub-band CQI offsets is finer than a granularity of quantization points on a negative side of the range of sub-band CQI offsets. As a particular example, there may be four quantization points (e.g., 8, 4, 2, and 1) on the positive side of the range of sub-band CQI offsets (e.g., the range from −15 to 15) and three quantization points (e.g., −1, −2, and −4) on the negative side of the range of sub-band CQI offsets. In some aspects, at least three quantization points in the set of quantization points are on the positive side of the sub-band CQI offset range. In some aspects, having more quantization points on the positive side of the range of sub-band CQI offsets improves accuracy of MCS selection performed based at least in part on CQI feedback, thereby enabling increased throughput.

In some aspects, a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets. That is, the set of quantization points may be unevenly distributed across the range of sub-band CQI offsets. In some aspects, a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets. As one example, in some aspects, the distribution of the set of quantization points may be non-linear (i.e., uneven) with respect to the range of sub-band CQI offsets and a granularity of the quantization points may be finer near a sub-band CQI offset of 0 than a sub-band CQI offset of ±15. In some aspects, a log-scale quantization can be used on the negative side of the range of sub-band CQI offsets or the positive side of the range of sub-band CQI offsets. In some aspects, non-linear distribution and/or a distribution with finer granularity near a middle sub-band CQI offset may be used because the distribution of actual sub-band CQI offset values is expected to be a Gaussian distribution with zero mean, meaning that sub-band CQI offsets near the middle of the range have a higher probability of occurring than sub-band CQI offsets at edges of the range. Therefore, non-linear distribution and/or distribution with finer granularity near the middle of the range may improve accuracy of MCS selection. As a particular example, with reference toFIG.3B, the distribution of the set of quantization points (e.g., −8, −4, −2, −1, 0, 1, 2, 4) is non-linear with respect to the range of sub-band CQI offsets. Further, in the example shown inFIG.3B, a granularity of the set of quantization points is finer near a middle sub-band CQI offset (e.g., 0) of the range of sub-band CQI offsets than near edges of the range of sub-band CQI offsets.

FIG.3Bis a diagram illustrating an example of a quantization table that can be used in association with providing three bit sub-band CQI feedback. Notably, in the example shown inFIG.3B, a quantity of negative quantization points is different than a quantity of positive quantization points, the distribution of the set of quantization points is non-linear, and a granularity of the set of quantization points is finer near a middle sub-band CQI offset, as noted above.

In some aspects, a quantization table indicating the set of quantization points and the associated sub-band differential CQI values is stored or configured on the UE120(e.g., according to an applicable wireless communication standard).

In some aspects, a quantization table indicating the set of quantization points and the associated sub-band differential CQI values is configured by the base station110. That is, in some aspects, the set of quantization points may be configurable by the base station110(e.g., rather than being store or configured on the UE120according to an applicable wireless communication standard). In some implementations, permitting configuration by the base station110enables the base station110to customize or optimize the set of quantization points based at least in part on, for example, a profile of a channel, an interference metric of the channel, a system bandwidth, a size of the sub-band, or another characteristic, which may improve accuracy of MCS selection and, therefore, improve reliability.

In some aspects, the set of quantization points is one of a plurality of sets of quantization points configured on the UE120, and an indication to use the set of quantization points is received from the base station110. For example, the UE120may be configured (e.g., according to an applicable wireless communication standard) with a plurality of X (X>1) quantization tables (each associated with a different set of quantization points), and the base station110may signal the UE120which quantization table to use (e.g., for a given bandwidth part). As a particular example, the base station110may signal the partition of the quantity of quantization points for the positive and negative sides of the sub-band CQI offset range by signaling the UE120to use a quantization table including X quantization points on the positive side of the range and 8−X quantization points on the negative side of the range. In this example, each value of X is associated with a different quantization table configured on the UE120. In other words, the UE120may be configured with nine quantization tables, each associated with one of nine possible values of X (e.g., X=0, 1, 2, . . . , 8), and the base station110may indicate one of the nine quantization tables by signaling a value of X.

As shown by reference310, the UE120may transmit an indication of the selected sub-band differential CQI value. In some aspects, the indication of the selected sub-band differential CQI value is transmitted in a three bit value corresponding to the selected sub-band differential CQI value. An example set of three bit values corresponding to the selected sub-band differential CQI value is provided in the left column of the table inFIG.3B.

As indicated above,FIGS.3A and3Bare provided as examples. Other examples may differ from what is described with respect toFIGS.3A and3B.

FIG.4is a diagram illustrating an example400associated with three bit sub-band CQI feedback, in accordance with the present disclosure. As shown inFIG.4, the example400includes communication between a base station110and a UE120. In some aspects, base station110and UE120may be included in a wireless network, such as wireless network100. Base station110and UE120may communicate via a wireless access link, which may include an uplink and a downlink

As shown inFIG.4, by reference405, the UE120may determine whether a set of. uplink resources to be used for transmitting a channel state information (CSI) communication is sufficient to permit a three bit sub-band differential CQI value to be transmitted in the CSI communication. For example, the UE120may determine (e.g., based at least in part on a CSI configuration or resource allocation indicated by a base station110) whether resources to be used for transmitting a CSI communication that is to carry sub-band CQI feedback is sufficient to permit a three bit sub-band differential CQI value to be transmitted.

As shown by reference410, the UE120may selectively transmit the three bit sub-band differential CQI value in the CSI communication based at least in part on the determination of whether the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

For example, in some aspects, the UE120may determine that the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication. In such an example, selectively transmitting the three bit sub-band differential CQI value includes transmitting the three bit sub-band differential CQI value in the CSI communication. That is, the UE120may transmit the three bit sub-band differential CQI value (e.g., along with a wideband CQI value) in the CSI communication based at least in part on a determination that the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

As another example, in some aspects, the UE120may determine that the set of uplink resources is insufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication. In some aspects, if the UE120determines that the set of uplink resources is insufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication, then the UE120may refrain from transmitting a sub-band differential CQI value in the CSI communication. That is, in some aspects, the UE120may refrain from transmitting a sub-band differential CQI value in the CSI communication based at least in part on a determination that the set of uplink resources is insufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication. In such a case, the UE120may still transmit a wideband CQI value in the CSI communication.

As another example, in some aspects, the UE120may determine that the set of uplink resources is insufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication. In some aspects, the UE120may then determine whether the set of uplink resources is sufficient to permit a two bit sub-band differential CQI value to be transmitted in the CSI communication. Here, if the UE120determines that the set of uplink resources is sufficient to permit the two bit sub-band differential CQI value to be transmitted in the CSI communication, then the UE120may determine a two bit sub-band differential CQI value (e.g., using a two bit sub-band differential CQI value quantization table configured on the UE120), and the UE120may transmit the two bit sub-band differential CQI value (e.g., along with a wideband CQI value) in the CSI communication accordingly. Conversely, if the UE120determines that the set of uplink resources is insufficient to permit the two bit sub-band differential CQI value to be transmitted in the CSI communication, then the UE120refrain from transmitting a sub-band differential CQI value in the CSI communication. Thus, in some aspects, the UE120may refrain from transmitting a sub-band differential CQI value in the CSI communication based at least in part on a determination that the set of uplink resources is insufficient to permit the three bit sub-band differential CQI value or the two bit sub-band differential CQI value to be transmitted in the CSI communication. In such a case, the UE120may still transmit a wideband CQI value in the CSI communication.

In some aspects, the UE120may determine whether the set of uplink resources is sufficient for all of multiple three bit sub-band differential CQI values (e.g., each associated with a different sub-band) to be transmitted in the CSI communication, and may selectively transmit all of the multiple three bit sub-band differential CQI values accordingly. That is, in some aspects, the UE120may determine whether the set of uplink resources is sufficient for all three bit sub-band differential CQI values to be transmitted and may selectively transmit all of the multiple three bit sub-band differential CQI values accordingly (e.g., the UE120may not transmit any three bit sub-band differential CQI values when the set of uplink resources is insufficient to transmit all of the three bit sub-band differential CQI values).

Alternatively, in some aspects, the UE120may determine whether the set of uplink resources is sufficient for each of multiple three bit sub-band differential CQI value to be transmitted in the CSI communication on an individual basis and may selectively transmit each of the multiple three bit sub-band differential CQI values accordingly. That is, in some aspects, the UE120may determine whether the set of uplink resources is sufficient for a first three bit sub-band differential CQI value to be transmitted, then determine whether a remaining portion of the set of uplink resources is sufficient for a second three bit sub-band differential CQI value to be transmitted, and so on. In some aspects, the UE120may make similar determinations for a two bit sub-band differential CQI value (e.g., after determining that a three bit sub-band differential CQI value cannot be transmitted in the set of uplink resources). In such a case, the UE120may transmit one or more three bit sub-band differential CQI values and/or one or more two bit sub-band differential CQIs based at least in part on these determinations. In some aspects, an order in which the UE120determines whether three bit sub-band differential CQI values can be transmitted in the set of uplink resources may be based at least in part on priorities of the sub-bands of the bandwidth part.

FIG.5is a diagram illustrating an example process500performed, for example, by a mobile station, in accordance with the present disclosure. Example process500is an example where the mobile station (e.g., a UE120) performs operations associated with three bit sub-band CQI feedback.

As shown inFIG.5, in some aspects, process500may include selecting a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, wherein a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points (block510). For example, the mobile station (e.g., using communication manager140and/or CQI feedback component808, depicted inFIG.8) may select a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, as described above. In some aspects, a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points.

As further shown inFIG.5, in some aspects, process500may include transmitting an indication of the selected sub-band differential CQI value (block520). For example, the mobile station (e.g., using communication manager140and/or transmission component804, depicted inFIG.8) may transmit an indication of the selected sub-band differential CQI value, as described above.

In a first aspect, the indication of the selected sub-band differential CQI value is transmitted in a three bit value corresponding to the selected sub-band differential CQI value.

In a second aspect, alone or in combination with the first aspect, a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets.

In a third aspect, alone or in combination with one or more of the first and second aspects, a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the set of quantization points is configured by a network entity (e.g., a base station).

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the set of quantization points is one of a plurality of sets of quantization points configured on the mobile station, and an indication to use the set of quantization points is received from a network entity (e.g., a base station).

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the quantity of negative quantization points in the set of quantization points is greater than the quantity of positive quantization points in the set of quantization points.

In a seventh aspect, alone or in combination with one or more of the first through fifth aspects, the quantity of negative quantization points in the set of quantization points is less than the quantity of positive quantization points in the set of quantization points.

FIG.6is a diagram illustrating an example process600performed, for example, by a mobile station, in accordance with the present disclosure. Example process600is an example where the mobile station (e.g., a UE120) performs operations associated with three bit sub-band CQI feedback.

As shown inFIG.6, in some aspects, process600may include selecting a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, wherein a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets, or wherein a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets (block610). For example, the mobile station (e.g., using communication manager140and/or CQI feedback component808, depicted inFIG.8) may select a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, as described above. In some aspects, a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets. In some aspects, a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets.

As further shown inFIG.6, in some aspects, process600may include transmitting an indication of the selected sub-band differential CQI value (block620). For example, the mobile station (e.g., using communication manager140and/or transmission component804, depicted inFIG.8) may transmit an indication of the selected sub-band differential CQI value, as described above.

In a first aspect, the indication of the selected sub-band differential CQI value is transmitted in a three bit value corresponding to the selected sub-band differential CQI value.

In a second aspect, alone or in combination with the first aspect, a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points.

In a third aspect, alone or in combination with one or more of the first and second aspects, the set of quantization points is configured on the mobile station by a network entity (e.g., a base station).

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the set of quantization points is one of a plurality of sets of quantization points configured on the mobile station, and an indication to use the set of quantization points is received from a network entity (e.g., a base station).

FIG.7is a diagram illustrating an example process700performed, for example, by a mobile station, in accordance with the present disclosure. Example process700is an example where the mobile station (e.g., a UE120) performs operations associated with three bit sub-band CQI feedback.

As shown inFIG.7, in some aspects, process700may include determining whether a set of uplink resources to be used for transmitting a CSI communication is sufficient to permit a three bit sub-band differential CQI value to be transmitted in the CSI communication (block710). For example, the mobile station (e.g., using communication manager140and/or CQI feedback component808, depicted inFIG.8) may determine whether a set of uplink resources to be used for transmitting a CSI communication is sufficient to permit a three bit sub-band differential CQI value to be transmitted in the CSI communication, as described above.

As further shown inFIG.7, in some aspects, process700may include selectively transmitting the three bit sub-band differential CQI value in the CSI communication based at least in part on the determination of whether the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication (block720). For example, the mobile station (e.g., using communication manager140and/or transmission component804, depicted inFIG.804) may selectively transmit the three bit sub-band differential CQI value in the CSI communication based at least in part on the determination of whether the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication, as described above.

In a first aspect, selectively transmitting the three bit sub-band differential CQI value comprises transmitting the three bit sub-band differential CQI value in the CSI communication based at least in part on a determination that the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

In a second aspect, alone or in combination with the first aspect, selectively transmitting the three bit sub-band differential CQI value comprises transmitting a two bit sub-band differential CQI value in the CSI communication based at least in part on a determination that the set of uplink resources is insufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

In a third aspect, alone or in combination with one or more of the first and second aspects, the two bit sub-band differential CQI value is transmitted in the CSI communication based at least in part on a determination that the set of uplink resources is sufficient to permit the two bit sub-band differential CQI value to be transmitted in the CSI communication.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, selectively transmitting the three bit sub-band differential CQI value comprises refraining from transmitting a sub-band differential CQI value in the CSI communication based at least in part on a determination that the set of uplink resources is insufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, refraining from transmitting the sub-band differential CQI value is further based at least in part on a determination that the set of uplink resources is insufficient to permit a two bit sub-band differential CQI value to be transmitted in the CSI communication.

In some aspects, the CQI feedback component808may select a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, wherein a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points. In some aspects, the transmission component804may transmit an indication of the selected sub-band differential CQI value.

In some aspects, the CQI feedback component808may select a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, wherein a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets, or wherein a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets. In some aspects, the transmission component804may transmit an indication of the selected sub-band differential CQI value.

In some aspects, the CQI feedback component808may determine whether a set of uplink resources to be used for transmitting a CSI communication is sufficient to permit a three bit sub-band differential CQI value to be transmitted in the CSI communication. In some aspects, the CQI feedback component808may selectively transmit, or may cause the transmission component804to selectively transmit, the three bit sub-band differential CQI value in the CSI communication based at least in part on the determination of whether the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

Aspect 1: A method of wireless communication performed by a mobile station, comprising: selecting, by the mobile station, a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, wherein a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points; and transmitting, by the mobile station, an indication of the selected sub-band differential CQI value.

Aspect 2: The method of Aspect 1, wherein the indication of the selected sub-band differential CQI value is transmitted in a three bit value corresponding to the selected sub-band differential CQI value.

Aspect 3: The method of any of Aspects 1-2, wherein a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets.

Aspect 4: The method of any of Aspects 1-3, wherein a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets.

Aspect 5: The method of any of Aspects 1-4, wherein the set of quantization points is configured by a base station.

Aspect 6: The method of any of Aspects 1-5, wherein the set of quantization points is one of a plurality of sets of quantization points configured on the mobile station, and an indication to use the set of quantization points is received from a network entity.

Aspect 7: The method of any of Aspects 1-6, wherein the quantity of negative quantization points in the set of quantization points is greater than the quantity of positive quantization points in the set of quantization points.

Aspect 8: The method of any of Aspects 1-6, wherein the quantity of negative quantization points in the set of quantization points is less than the quantity of positive quantization points in the set of quantization points.

Aspect 9: A method of wireless communication performed by a mobile station, comprising: selecting, by the mobile station, a sub-band differential CQI value from a plurality of sub-band differential CQI values, the sub-band differential CQI value being selected based at least in part on a sub-band CQI offset and a set of quantization points associated with the plurality of sub-band differential CQI values and a range of sub-band CQI offsets, wherein a distribution of the set of quantization points is non-linear with respect to the range of sub-band CQI offsets, or wherein a granularity of the set of quantization points is finer near a middle sub-band CQI offset, of the range of sub-band CQI offsets, than near an edge sub-band CQI offset of the range of sub-band CQI offsets; and transmitting, by the mobile station, an indication of the selected sub-band differential CQI value.

Aspect 10: The method of Aspect 9, wherein the indication of the selected sub-band differential CQI value is transmitted in a three bit value corresponding to the selected sub-band differential CQI value.

Aspect 11: The method of any of Aspects 9-10, wherein a quantity of negative quantization points in the set of quantization points is different than a quantity of positive quantization points in the set of quantization points.

Aspect 12: The method of any of Aspects 9-11, wherein the set of quantization points is configured on the mobile station by a network entity.

Aspect 13: The method of any of Aspects 9-12, wherein the set of quantization points is one of a plurality of sets of quantization points configured on the mobile station, and an indication to use the set of quantization points is received from a network entity.

Aspect 14: A method of wireless communication performed by a mobile station, comprising: determining, by a mobile station, whether a set of uplink resources to be used for transmitting a CSI communication is sufficient to permit a three bit sub-band differential CQI value to be transmitted in the CSI communication; and selectively transmitting, by the mobile station, the three bit sub-band differential CQI value in the CSI communication based at least in part on the determination of whether the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

Aspect 15: The method of Aspect 14, wherein selectively transmitting the three bit sub-band differential CQI value comprises transmitting the three bit sub-band differential CQI value in the CSI communication based at least in part on a determination that the set of uplink resources is sufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

Aspect 16: The method of Aspect 14, wherein selectively transmitting the three bit sub-band differential CQI value comprises transmitting a two bit sub-band differential CQI value in the CSI communication based at least in part on a determination that the set of uplink resources is insufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

Aspect 17: The method of Aspect 16, wherein the two bit sub-band differential CQI value is transmitted in the CSI communication based at least in part on a determination that the set of uplink resources is sufficient to permit the two bit sub-band differential CQI value to be transmitted in the CSI communication.

Aspect 18: The method of Aspect 14, wherein selectively transmitting the three bit sub-band differential CQI value comprises refraining from transmitting a sub-band differential CQI value in the CSI communication based at least in part on a determination that the set of uplink resources is insufficient to permit the three bit sub-band differential CQI value to be transmitted in the CSI communication.

Aspect 19: The method of Aspect 18, wherein refraining from transmitting the sub-band differential CQI value is further based at least in part on a determination that the set of uplink resources is insufficient to permit a two bit sub-band differential CQI value to be transmitted in the CSI communication.

Aspect 27: An apparatus for wireless communication, comprising at least one means for performing the method of one or more of Aspects 9-13.