# US 2023/0067166 A1 · Reporting below a minimum modulation and coding scheme > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2023/0067166 A1 - Document ID: US20230067166A1 - Status: Published application - Kind: A1 - Application number: 17/446,253 - Filed: 2021-08-27 - Published: 2023-03-02 - Earliest claimed: 2021-08-27 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Ahmed ELSHAFIE; Seyedkianoush HOSSEINI; Yi HUANG - Web page: https://patentgrep.com/patent/US20230067166A1 ## CPC - H04B 7/0626: {Channel coefficients, e.g. channel state information [CSI]} - H04L 1/0005: {applied to payload information} - H04L 1/001: {applied to control information} - H04L 1/0011: {applied to payload information} - H04L 1/0016: {involving special memory structures, e.g. look-up tables} - H04L 1/0025: {Transmission of mode-switching indication} - H04L 5/0057: {Physical resource allocation for CQI} - H04L 5/0094: {Indication of how sub-channels of the path are allocated} - H04W 72/21: in the uplink direction of a wireless link, i.e. towards the network - H04L 1/0017: {where the mode-switching is based on Quality of Service requirement} - H04L 1/0027: {Scheduling of signalling, e.g. occurrence thereof} - H04L 1/0029: {Reduction of the amount of signalling, e.g. retention of useful signalling or differential signalling (power control H04W52/04)} - H04L 1/1854: {Scheduling and prioritising arrangements} - H04B: TRANSMISSION - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may transmit, to a base station, channel state information (CSI) feedback indicating a modulation and coding scheme (MCS) associated with a spectral efficiency below a minimum MCS index in a spectral efficiency table. The UE may receive, from the base station, a downlink transmission including a number of resource blocks (RBs), wherein the number of RBs is based at least in part on the spectral efficiency associated with the MCS indicated in the CSI feedback. Numerous other aspects are described. ## Claims ### Claim 1 A method of wireless communication performed by a user equipment (UE), comprising: transmitting, to a base station, channel state information (CSI) feedback indicating a modulation and coding scheme (MCS) associated with a spectral efficiency below a minimum MCS index in a spectral efficiency table; and receiving, from the base station, a downlink transmission including a number of resource blocks (RBs), wherein the number of RBs is based at least in part on the spectral efficiency associated with the MCS indicated in the CSI feedback. ### Claim 2 (depends on 1) The method of claim 1, wherein the MCS indicated in the CSI feedback is mapped to an entry, in the spectral efficiency table, that is included among one or more entries associated with lower spectral efficiencies than the minimum MCS index. ### Claim 3 (depends on 1) The method of claim 1, wherein the MCS indicated in the CSI feedback is mapped to an entry in a very low spectral efficiency table that includes one or more entries associated with lower spectral efficiencies than the minimum MCS index in the spectral efficiency table. ### Claim 4 (depends on 3) The method of claim 3, wherein the CSI feedback includes a one-bit field to indicate that the very low spectral efficiency table is used to indicate the MCS. ### Claim 5 (depends on 3) The method of claim 3, wherein the entry in the very low spectral efficiency table mapped to the MCS is indicated in an uplink control information (UCI) field. ### Claim 6 (depends on 1) The method of claim 1, wherein the CSI feedback includes a delta MCS value to indicate the MCS associated with the spectral efficiency below the minimum MCS index in the spectral efficiency table. ### Claim 7 (depends on 1) The method of claim 1, wherein the MCS indicated in the CSI feedback is based at least in part on a physical downlink shared channel decoding result. ### Claim 8 (depends on 1) The method of claim 1, wherein the CSI feedback includes a first stage uplink control information (UCI) to indicate that the MCS is associated with the spectral efficiency below the minimum MCS index in the spectral efficiency table and a second stage UCI to indicate one or more parameters related to the number of RBs to be included in the downlink transmission from the base station. ### Claim 9 (depends on 8) The method of claim 8, wherein the one or more parameters indicated in the second stage UCI include a residual number of RBs to add to a number of RBs associated with the minimum MCS index in the spectral efficiency table. ### Claim 10 (depends on 8) The method of claim 8, wherein the one or more parameters indicated in the second stage UCI include a residual spectral efficiency to add to a spectral efficiency associated with the minimum MCS index in the spectral efficiency table. ### Claim 11 (depends on 1) The method of claim 1, wherein the MCS associated with the spectral efficiency below the minimum MCS index in the spectral efficiency table is selected to satisfy a target block error rate (BLER) for the downlink transmission. ### Claim 12 A method of wireless communication performed by a base station, comprising: receiving, from a user equipment (UE), channel state information (CSI) feedback indicating a modulation and coding scheme (MCS) associated with a spectral efficiency below a minimum MCS index in a spectral efficiency table; and transmitting, to the UE, a downlink transmission including a number of resource blocks (RBs), wherein the number of RBs is based at least in part on the spectral efficiency associated with the MCS indicated in the CSI feedback. ### Claim 13 (depends on 12) The method of claim 12, wherein the MCS indicated in the CSI feedback is mapped to an entry, in the spectral efficiency table, that is included among one or more entries associated with lower spectral efficiencies than the minimum MCS index. ### Claim 14 (depends on 12) The method of claim 12, wherein the MCS indicated in the CSI feedback is mapped to an entry in a very low spectral efficiency table that includes one or more entries associated with lower spectral efficiencies than the minimum MCS index in the spectral efficiency table. ### Claim 15 (depends on 14) The method of claim 14, wherein the CSI feedback includes a one-bit field to indicate that the very low spectral efficiency table is used to indicate the MCS. ### Claim 16 (depends on 14) The method of claim 14, wherein the entry in the very low spectral efficiency table mapped to the MCS is indicated in an uplink control information (UCI) field. ### Claim 17 (depends on 12) The method of claim 12, wherein the CSI feedback includes a delta MCS value to indicate the MCS associated with the spectral efficiency below the minimum MCS index in the spectral efficiency table. ### Claim 18 (depends on 12) The method of claim 12, wherein the MCS indicated in the CSI feedback is based at least in part on a physical downlink shared channel decoding result. ### Claim 19 (depends on 12) The method of claim 12, wherein the CSI feedback includes a first stage uplink control information (UCI) to indicate that the MCS is associated with the spectral efficiency below the minimum MCS index in the spectral efficiency table and a second stage UCI to indicate one or more parameters related to the number of RBs to be included in the downlink transmission from the base station. ### Claim 20 (depends on 19) The method of claim 19, wherein the one or more parameters indicated in the second stage UCI include a residual number of RBs to add to a number of RBs associated with the minimum MCS index in the spectral efficiency table. ### Claim 21 (depends on 19) The method of claim 19, wherein the one or more parameters indicated in the second stage UCI include a residual spectral efficiency to add to a spectral efficiency associated with the minimum MCS index in the spectral efficiency table. ### Claim 22 (depends on 12) The method of claim 12, wherein the MCS associated with the spectral efficiency below the minimum MCS index in the spectral efficiency table is selected to satisfy a target block error rate (BLER) for the downlink transmission. ### Claim 23 A user equipment (UE) for wireless communication, comprising: a memory; and one or more processors, coupled to the memory, configured to: transmit, to a base station, channel state information (CSI) feedback indicating a modulation and coding scheme (MCS) associated with a spectral efficiency below a minimum MCS index in a spectral efficiency table; and receive, from the base station, a downlink transmission including a number of resource blocks (RBs), wherein the number of RBs is based at least in part on the spectral efficiency associated with the MCS indicated in the CSI feedback. ### Claim 24 (depends on 23) The UE of claim 23, wherein the MCS indicated in the CSI feedback is mapped to an entry, in the spectral efficiency table, that is included among one or more entries associated with lower spectral efficiencies than the minimum MCS index. ### Claim 25 (depends on 23) The UE of claim 23, wherein the MCS indicated in the CSI feedback is mapped to an entry in a very low spectral efficiency table that includes one or more entries associated with lower spectral efficiencies than the minimum MCS index in the spectral efficiency table. ### Claim 26 (depends on 23) The UE of claim 23, wherein the CSI feedback includes a delta MCS value to indicate the MCS associated with the spectral efficiency below the minimum MCS index in the spectral efficiency table. ### Claim 27 A base station for wireless communication, comprising: a memory; and one or more processors, coupled to the memory, configured to: receive, from a user equipment (UE), channel state information (CSI) feedback indicating a modulation and coding scheme (MCS) associated with a spectral efficiency below a minimum MCS index in a spectral efficiency table; and transmit, to the UE, a downlink transmission including a number of resource blocks (RBs), wherein the number of RBs is based at least in part on the spectral efficiency associated with the MCS indicated in the CSI feedback. ### Claim 28 (depends on 27) The base station of claim 27, wherein the MCS indicated in the CSI feedback is mapped to an entry, in the spectral efficiency table, that is included among one or more entries associated with lower spectral efficiencies than the minimum MCS index. ### Claim 29 (depends on 27) The base station of claim 27, wherein the MCS indicated in the CSI feedback is mapped to an entry in a very low spectral efficiency table that includes one or more entries associated with lower spectral efficiencies than the minimum MCS index in the spectral efficiency table. ### Claim 30 (depends on 27) The base station of claim 27, wherein the CSI feedback includes a delta MCS value to indicate the MCS associated with the spectral efficiency below the minimum MCS index in the spectral efficiency table.