# US 2022/0286341 A1 · Generalization of encoding for uplink transmissions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0286341 A1 - Document ID: US20220286341A1 - Status: Published application - Kind: A1 - Application number: 17/187,522 - Filed: 2021-02-26 - Published: 2022-09-08 - Earliest claimed: 2021-02-26 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Ahmed Elshafie; Yi Huang; Hwan Joon Kwon - Web page: https://patentgrep.com/patent/US20220286341A1 ## CPC - H04L 27/103: {Chirp modulation (for spread spectrum techniques H04B1/69)} - H04L 27/2628: {Inverse Fourier transform modulators, e.g. inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators (H04L27/2634 takes precedence)} - H04L 5/0048: {Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091)} - H04L 27/26035: {Maintenance of orthogonality, e.g. for signals exchanged between cells or users, or by using covering codes or sequences (using different training sequence per antenna H04B7/0684; code allocation H04J13/16)} - H04L 27/261: {Details of reference signals} - H04L 27/2639: {Modulators using other transforms, e.g. discrete cosine transforms, Orthogonal Time Frequency and Space [OTFS] or hermetic transforms} - H04W 72/21: in the uplink direction of a wireless link, i.e. towards the network - 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 Methods, systems, and devices for wireless communications are described. Generally, a user equipment (UE) may identify an angle parameter for encoding uplink messages using a fractional Fourier Transform (FrFFT). A base station may transmit a set of angle parameters or a single angle parameter that the UE is to use for encoding an uplink message. The UE may select an alpha value from the set of alpha values for the encoding. The UE may transmit an indication of a set of proposed angle parameters to the base station, and the base station may determine and indicate one of or a subset of the received set of proposed angle parameters to the UE. The base station may indicate a correspondence between angle parameters and beam configurations, and the UE may identify an alpha parameter value based on a subsequently indicated beam configuration. ## Claims ### Claim 1 A method for wireless communications at a user equipment (UE), comprising: receiving, from a base station, an indication of a first set of angle parameters for the UE to use for an inverse fractional Fourier transform; encoding an uplink message using the inverse fractional Fourier transform according to an angle parameter of the first set of angle parameters; and transmitting, to the base station on an uplink channel, the uplink message that is encoded using the fractional Fourier transform according to the indicated angle parameter. ### Claim 2 (depends on 1) The method of claim 1, further comprising: receiving, from the base station, an indication of the angle parameter of the first set of angle parameters for the UE to use for the inverse fractional Fourier transform. ### Claim 3 (depends on 1) The method of claim 1, further comprising: selecting, by the UE, a second set of angle parameters comprising the angle parameter; and transmitting, to the base station, an indication of the selected second set of angle parameters, wherein receiving the indication of the first set of angle parameters is responsive at least in part to the first set of angle parameters. ### Claim 4 (depends on 1) The method of claim 1, further comprising: transmitting, to the base station, an indication of a second set of angle parameters comprising the angle parameter, wherein the indication of the first set of angle parameters is received at least in part in response to the transmitted indication of the second set of angle parameters; selecting, from the first set of angle parameters, a plurality of angle parameters comprising the angle parameter; transmitting, to the base station, an indication of the selection; and receiving an indication of the angle parameter at least in part in response to the transmitted indication of the selection. ### Claim 5 (depends on 1) The method of claim 1, wherein receiving the indication of the first set of angle parameters comprises: receiving a configuration indicating a correspondence between a set of beam configurations and the first set of angle parameters. ### Claim 6 (depends on 5) The method of claim 5, further comprising: receiving, from the base station, an indication of a beam configuration associated with the uplink message; and selecting the angle parameter from the first set of angle parameters based at least in part on receiving the indication of the beam configuration and the correspondence, wherein encoding the uplink message is based at least in part on the selecting. ### Claim 7 (depends on 1) The method of claim 1, wherein receiving the indication of the first set of angle parameters comprises: receiving a configuration indicating a correspondence between a set of quasi co-location configurations and the first set of angle parameters. ### Claim 8 (depends on 7) The method of claim 7, further comprising: receiving, from the base station, an indication of a quasi co-location configuration associated with the uplink channel; and selecting the angle parameter from the first set of angle parameters based at least in part on receiving the indication of the quasi co-location configuration and the correspondence, wherein encoding the uplink message is based at least in part on the selecting. ### Claim 9 (depends on 1) The method of claim 1, wherein receiving the indication of the first set of angle parameters comprises: receiving a configuration indicating a correspondence between a set of channel conditions and the first set of angle parameters. ### Claim 10 (depends on 9) The method of claim 9, further comprising: determining channel state conditions at the UE; and selecting the angle parameter from the first set of angle parameters based at least in part on determining the channel state conditions and the correspondence, wherein encoding the uplink message is based at least in part on the selecting. ### Claim 11 (depends on 1) The method of claim 1, further comprising: transmitting, to the base station, an indication of a Doppler estimate, wherein the indication of the first set of angle parameters is received at least in part in response to the transmitted indication of the Doppler estimate. ### Claim 12 (depends on 1) The method of claim 1, further comprising: receiving an index value corresponding to the angle parameter, wherein receiving the indication of the first set of angle parameters comprises receiving a list of angle parameters, each angle parameter corresponding to one index of the list. ### Claim 13 (depends on 1) The method of claim 1, wherein receiving the indication of the first set of angle parameters comprises: receiving a radio resource control message, a media access control (MAC) control element (CE), a downlink control information message, or any combination thereof, comprising the indication of the first set of angle parameters. ### Claim 14 (depends on 1) The method of claim 1, wherein encoding the uplink message comprises: converting a set of information bits associated with the uplink message to a decimal value based at least in part on the angle parameter; selecting a sequence from a pool of sequences based at least in part on the decimal value and the angle parameter; and mapping the selected sequence to one or more resource elements on the uplink channel. ### Claim 15 (depends on 1) The method of claim 1, wherein the uplink message on the uplink channel comprises an uplink control information message on an uplink control channel. ### Claim 16 (depends on 1) The method of claim 1, wherein the transmitted uplink message lacks an associated demodulation reference signal. ### Claim 17 A method for wireless communications at a base station, comprising: transmitting, to a user equipment (UE), an indication of a first set of angle parameters for the UE to use to encode uplink messages using an inverse fractional Fourier transform; receiving an uplink message from the UE on an uplink channel; and decoding the uplink message using a fractional Fourier transform according to an angle parameter of the first set of angle parameters. ### Claim 18 (depends on 17) The method of claim 17, further comprising: receiving, from the UE, an indication of a second set of angle parameters comprising the angle parameter; and selecting the first set of angle parameters based at least in part on the first set of angle parameters from the UE. ### Claim 19 (depends on 17) The method of claim 17, wherein transmitting the indication of the first set of angle parameters comprises: transmitting a configuration indicating a correspondence between a set of beam configurations and the first set of angle parameters. ### Claim 20 (depends on 17) The method of claim 17, wherein transmitting the indication of the first set of angle parameters comprises: transmitting a configuration indicating a correspondence between a set of quasi co-location configurations and the first set of angle parameters. ### Claim 21 (depends on 17) The method of claim 17, wherein transmitting the indication of the first set of angle parameters comprises: transmitting a configuration indicating a correspondence between a set of channel conditions and individual ones of a set of angle parameters. ### Claim 22 (depends on 17) The method of claim 17, further comprising: receiving, from the UE, an indication of a Doppler estimate, wherein the indication of the first set of angle parameters is transmitted based at least in part on receiving the indication of the Doppler estimate. ### Claim 23 An apparatus for wireless communications at a user equipment (UE), comprising: a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to: receive, from a base station, an indication of a first set of angle parameters for the UE to use for an inverse fractional Fourier transform; encode an uplink message using the inverse fractional Fourier transform according to an angle parameter of the first set of angle parameters; and transmit, to the base station on an uplink channel, the uplink message that is encoded using the fractional Fourier transform according to the indicated angle parameter. ### Claim 24 (depends on 23) The apparatus of claim 23, wherein the instructions are further executable by the processor to cause the apparatus to: receive, from the base station, an indication of the angle parameter of the first set of angle parameters for the UE to use for the inverse fractional Fourier transform. ### Claim 25 (depends on 23) The apparatus of claim 23, wherein the instructions are further executable by the processor to cause the apparatus to: selecting, by the UE, a second set of angle parameters comprise the angle parameter; and transmit, to the base station, an indication of the selected second set of angle parameters, wherein receiving the indication of the first set of angle parameters is responsive at least in part to the first set of angle parameters. ### Claim 26 (depends on 23) The apparatus of claim 23, wherein the instructions are further executable by the processor to cause the apparatus to: transmit, to the base station, an indication of a second set of angle parameters comprising the angle parameter, wherein the indication of the first set of angle parameters is received at least in part in response to the transmitted indication of the second set of angle parameters; select, from the first set of angle parameters, a plurality of angle parameters comprising the angle parameter; transmit, to the base station, an indication of the selection; and receive an indication of the angle parameter at least in part in response to the transmitted indication of the selection. ### Claim 27 (depends on 23) The apparatus of claim 23, wherein the instructions to receive the indication of the first set of angle parameters are executable by the processor to cause the apparatus to: receive a configuration indicating a correspondence between a set of beam configurations and the first set of angle parameters. ### Claim 28 (depends on 23) The apparatus of claim 23, wherein the instructions to receive the indication of the first set of angle parameters are executable by the processor to cause the apparatus to: receive a configuration indicating a correspondence between a set of quasi co-location configurations and the first set of angle parameters. ### Claim 30 (depends on 23) The apparatus of claim 23, wherein the instructions to receive the indication of the first set of angle parameters are executable by the processor to cause the apparatus to: receive a configuration indicating a correspondence between a set of channel conditions and the first set of angle parameters. ### Claim 30 An apparatus for wireless communications at a base station, comprising: a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to: transmit, to a user equipment (UE), an indication of a first set of angle parameters for the UE to use to encode uplink messages using an inverse fractional Fourier transform; receive an uplink message from the UE on an uplink channel; and decode the uplink message using a fractional Fourier transform according to an angle parameter of the first set of angle parameters.