# US 12,191,993 B2 · Bit replacing for low density parity check encoding > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,191,993 B2 - Document ID: US12191993B2 - Status: Granted - Kind: B2 - Application number: 18/261,982 - Filed: 2021-03-18 - Published: 2024-03-21 - Granted: 2025-01-07 - Earliest claimed: 2021-03-18 - Assignees: QUALCOMM Incorporated - Applicants: Qualcomm Incorporated - Inventors: Wei Liu; Thomas Joseph Richardson; Liangming Wu; Changlong Xu; Ori Shental; Hao Xu - Web page: https://patentgrep.com/patent/US12191993B2 ## CPC - H03M 13/6393: {Rate compatible low-density parity check [LDPC] codes} - H04L 1/0041: {Arrangements at the transmitter end} - H03M 13/1148: {Structural properties of the code parity-check or generator matrix} - H03M 13/116: {Quasi-cyclic LDPC [QC-LDPC] codes, i.e. the parity-check matrix being composed of permutation or circulant sub-matrices} - H03M 13/1185: {wherein the parity-check matrix comprises a part with a double-diagonal} - H03M 13/616: {Matrix operations, especially for generator matrices or check matrices, e.g. column or row permutations} - H03M 13/6362: {by puncturing} - H04L 1/0045: {Arrangements at the receiver end} - H04L 1/0057: {Block codes (H04L1/0061, H04L1/0064 take precedence)} - H04L 1/0068: {by puncturing} - H03M: CODING; DECODING; CODE CONVERSION IN GENERAL (using fluidic means F15C4/00; optical analogue/digital converters G02F7/00; coding, decoding or code conversion, specially adapted for particular applications, see the relevant subclasses, e.g. G01D, G01R, G06F, G06T, G09G, G10L, G11B, G11C, H04B, H04L, H04M, H04N; ciphering or deciphering for cryptography or other purposes involving the need for secrecy G09C) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Methods, systems, and devices for wireless communication are described to support replacing values of one or more information bit vectors with one or more corresponding sets of parity bits. A first wireless device may replace an information bit vector with a parity bit vector, using a set of information bits of the information bit vector and based on a parity check matrix, which may result in generating the set of information bits at an information bit vector corresponding to a parity bit column of the parity check matrix, during encoding. The first wireless device may perform a transmission to a second wireless device, which may receive the transmission, decode the set of information bits to the information bit vector corresponding to the parity bit column. The second wireless device may replace other bit estimates of a vector corresponding to an information bit column with the set of information bits. ## Claims ### Claim 1 A method for wireless communication, comprising: generating a first plurality of vectors each comprising a respective set of information bits having a first quantity, wherein each vector of the first plurality is associated with a respective index indicating an order of the first plurality of vectors with respect to a lifted parity check matrix; replacing a first set of information bits of a first vector of the first plurality of vectors with a first set of parity bits having the first quantity, wherein the first set of parity bits is based at least in part on the first set of information bits; encoding the first plurality of vectors according to the lifted parity check matrix and the replacing; and performing, at a first wireless device, a transmission to a second wireless device based at least in part on the encoding. ### Claim 2 (depends on 1) The method of claim 1, further comprising: replacing a second set of information bits of a second vector of the first plurality of vectors with a second set of parity bits having the first quantity, wherein the second set of parity bits is based at least in part on the second set of information bits. ### Claim 3 (depends on 2) The method of claim 2, further comprising: determining the second set of parity bits based at least in part on the second set of information bits and the first set of parity bits, wherein replacing the second set of information bits is based at least in part on determining the second set of parity bits. ### Claim 4 (depends on 2) The method of claim 2, further comprising: determining the second set of parity bits based at least in part on the second set of information bits, the first set of parity bits, and a group of one or more third sets of information bits each corresponding to a respective vector of the first plurality of vectors, wherein replacing the second set of information bits is based at least in part on determining the second set of parity bits. ### Claim 5 (depends on 2) The method of claim 2, wherein encoding the first plurality of vectors comprises: generating a second plurality of vectors each comprising a respective set of bits having the first quantity, the second plurality of vectors including a third vector that comprises the second set of information bits based at least in part on replacing the second set of information bits of the second vector. ### Claim 6 (depends on 5) The method of claim 5, wherein the transmission comprises the second set of information bits based at least in part on generating the second plurality of vectors. ### Claim 7 (depends on 5) The method of claim 5, further comprising: puncturing the second vector after generating the second plurality of vectors. ### Claim 8 (depends on 1) The method of claim 1, further comprising: determining the first set of parity bits based at least in part on the first set of information bits and a group of one or more second sets of information bits each corresponding to a respective vector of the first plurality of vectors, wherein replacing the first set of information bits is based at least in part on determining the first set of parity bits. ### Claim 9 (depends on 1) The method of claim 1, wherein encoding the first plurality of vectors comprises: generating a second plurality of vectors each comprising a respective set of bits having the first quantity, the second plurality of vectors including a fourth vector that comprises the first set of information bits based at least in part on replacing the first set of information bits of the first vector. ### Claim 10 (depends on 9) The method of claim 9, further comprising: puncturing the first vector after generating the second plurality of vectors. ### Claim 11 (depends on 1) The method of claim 1, wherein encoding the first plurality of vectors comprises: performing a low density parity check encoding process on the first plurality of vectors. ### Claim 12 (depends on 1) The method of claim 1, wherein the transmission comprises the first set of information bits based at least in part on the encoding. ### Claim 13 (depends on 1) The method of claim 1, wherein generating the first plurality of vectors comprises: performing an amplitude shaping process on the first plurality of vectors. ### Claim 14 (depends on 1) The method of claim 1, wherein the lifted parity check matrix comprises: a set of first columns, each first column associated with a respective index corresponding to a vector of the first plurality of vectors; a set of second columns, each second column associated with a respective index corresponding to a vector of a second plurality of vectors each comprising a respective set of parity bits having the first quantity; and a set of rows, each row corresponding to a parity check equation for generating a respective vector of the second plurality of vectors. ### Claim 15 A method for wireless communication, comprising: receiving a transmission from a first wireless device at a second wireless device; decoding the transmission into a first plurality of vectors each comprising a respective set of bits having a first quantity and a second plurality of vectors each comprising a respective set of bits having the first quantity, wherein each vector of the first plurality and the second plurality is associated with a respective index indicating an order of the first plurality of vectors and the second plurality of vectors with respect to a lifted parity check matrix; replacing a first set of bits of a first vector of the first plurality of vectors with a first set of information bits of a fourth vector of the second plurality of vectors, wherein the first set of information bits is associated with the first vector; and identifying a plurality of information bits of the transmission based at least in part on the replacing. ### Claim 16 (depends on 15) The method of claim 15, wherein decoding the transmission comprises: decoding the first set of information bits to the fourth vector; and setting a log-likelihood ratio of the first vector to a value of zero, wherein the first set of bits of the first vector is determined based at least in part on setting the log-likelihood ratio of the first vector to a value of zero. ### Claim 17 (depends on 15) The method of claim 15, wherein the fourth vector is associated with a first parity bit column of the lifted parity check matrix. ### Claim 18 (depends on 15) The method of claim 15, wherein decoding the transmission comprises: decoding a second set of information bits to a third vector of the second plurality of vectors. ### Claim 19 (depends on 18) The method of claim 18, wherein the third vector is associated with a second parity bit column of the lifted parity check matrix. ### Claim 20 (depends on 18) The method of claim 18, further comprising: replacing a second set of bits of a second vector of the first plurality of vectors with the second set of information bits. ### Claim 21 (depends on 20) The method of claim 20, wherein decoding the transmission comprises: setting a log-likelihood ratio of the second vector to a value of zero, wherein the second set of bits of the second vector is determined based at least in part on setting the log-likelihood ratio of the second vector to a value of zero. ### Claim 22 (depends on 15) The method of claim 15, wherein decoding the transmission comprises: performing a low density parity check decoding process on the transmission. ### Claim 23 (depends on 15) The method of claim 15, wherein the lifted parity check matrix comprises: a set of first columns, each first column associated with a respective index corresponding to a vector of the first plurality of vectors; a set of second columns, each second column associated with a respective index corresponding to a vector of the second plurality of vectors; and a set of rows, each row corresponding to a parity check equation for generating a respective vector of the second plurality of vectors. ### Claim 24 An apparatus for wireless communication, comprising: a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to: generate a first plurality of vectors each comprising a respective set of information bits having a first quantity, wherein each vector of the first plurality is associated with a respective index indicating an order of the first plurality of vectors with respect to a lifted parity check matrix; replace a first set of information bits of a first vector of the first plurality of vectors with a first set of parity bits having the first quantity, wherein the first set of parity bits is based at least in part on the first set of information bits; encode the first plurality of vectors according to the lifted parity check matrix and the replacing; and perform, at a first wireless device, a transmission to a second wireless device based at least in part on the encoding. ### Claim 25 (depends on 24) The apparatus of claim 24, wherein the instructions are further executable by the processor to cause the apparatus to: replace a second set of information bits of a second vector of the first plurality of vectors with a second set of parity bits having the first quantity, wherein the second set of parity bits is based at least in part on the second set of information bits. ### Claim 26 (depends on 25) The apparatus of claim 25, wherein the instructions to encode the first plurality of vectors are executable by the processor to cause the apparatus to: generate a second plurality of vectors each comprising a respective set of bits having the first quantity, the second plurality of vectors including a third vector that comprises the second set of information bits based at least in part on replacing the second set of information bits of the second vector. ### Claim 27 (depends on 24) The apparatus of claim 24, wherein the instructions to encode the first plurality of vectors are executable by the processor to cause the apparatus to: generate a second plurality of vectors each comprising a respective set of bits having the first quantity, the second plurality of vectors including a fourth vector that comprises the first set of information bits based at least in part on replacing the first set of information bits of the first vector. ### Claim 28 An apparatus for wireless communication, 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 a transmission from a first wireless device at a second wireless device; decode the transmission into a first plurality of vectors each comprising a respective set of bits having a first quantity and a second plurality of vectors each comprising a respective set of bits having the first quantity, wherein each vector of the first plurality and the second plurality is associated with a respective index indicating an order of the first plurality of vectors and the second plurality of vectors with respect to a lifted parity check matrix; replace a first set of bits of a first vector of the first plurality of vectors with a first set of information bits of a fourth vector of the second plurality of vectors, wherein the first set of information bits associated with the first vector; and identify a plurality of information bits of the transmission based at least in part on the replacing. ### Claim 29 (depends on 28) The apparatus of claim 28, wherein the instructions to decode the transmission are executable by the processor to cause the apparatus to: decode a second set of information bits to a third vector of the second plurality of vectors. ### Claim 30 (depends on 29) The apparatus of claim 29, wherein the instructions are further executable by the processor to cause the apparatus to: replace a second set of bits of a second vector of the first plurality of vectors with the second set of information bits.