# US 12,003,321 B2 · Wireless communication system, wireless communication device, receiver, control circuit, and storage medium > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,003,321 B2 - Document ID: US12003321B2 - Status: Granted - Kind: B2 - Application number: 17/372,890 - Filed: 2021-07-12 - Published: 2021-11-04 - Granted: 2024-06-04 - Earliest claimed: 2019-02-22 - Assignees: Mitsubishi Electric Corporation - Applicants: Mitsubishi Electric Corporation - Inventors: Masatsugu Higashinaka - Web page: https://patentgrep.com/patent/US12003321B2 ## CPC - H03M 13/256: {with trellis coding, e.g. with convolutional codes and TCM} - H04L 1/0041: {Arrangements at the transmitter end} - H03M 13/19: Single error correction without using particular properties of the cyclic codes, e.g. Hamming codes, extended or generalised Hamming codes - H03M 13/6325: {Error control coding in combination with demodulation} - H03M 13/6362: {by puncturing} - H04L 1/0045: {Arrangements at the receiver end} - H04L 1/0054: {Maximum-likelihood or sequential decoding, e.g. Viterbi, Fano, ZJ algorithms} - H04L 1/0059: {Convolutional codes} - H04L 1/006: {Trellis-coded modulation} - 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 A system includes: a transmitter including: a coding unit generating a first bit sequence by convolutional coding on information bits based on a code rate; a bit erasing unit generating a second bit sequence by erasing one or more bits from the first bit sequence for every predetermined first number of bits; and a modulation unit generating a symbol by modulation using the second bit sequence; and a receiver including: a demodulation unit calculating first reliabilities that can be derived from the symbol; a likelihood extension unit generating extended bit sequences each composed of bits for the first number of bits, and generating a plurality of second reliabilities by assigning first reliabilities duplicated, as the reliabilities of the extended bit sequences; and a decoding unit creating a trellis diagram using the code rate and the extended bit sequences, and assigning the second reliabilities to branches of the trellis diagram. ## Claims ### Claim 1 A wireless communication system comprising: a transmitter comprising: a coder to generate a first bit sequence by performing convolutional coding on an information bit on the basis of a code rate; a bit eraser to generate a second bit sequence by erasing one or more bits from the first bit sequence for every predetermined first number of bits; and a modulator to generate a symbol by modulation using the second bit sequence; and a receiver comprising: a demodulator to calculate a plurality of first reliabilities that are reliabilities of a plurality of bit sequences that can be derived from the symbol; a likelihood extender to generate a plurality of extended bit sequences that are bit sequences each composed of bits for the first number of bits, and generate a plurality of second reliabilities that are reliabilities of the plurality of extended bit sequences by assigning a plurality of first reliabilities duplicated, as the reliabilities of the plurality of extended bit sequences; and a decoder to create a trellis diagram using the code rate and the plurality of extended bit sequences, and perform decoding by assigning the plurality of second reliabilities to a plurality of branches of the trellis diagram. ### Claim 2 (depends on 1) The wireless communication system according to claim 1, wherein the number of bits of the branch is equal to a common multiple of a reciprocal of the code rate and the first number of bits. ### Claim 3 (depends on 2) The wireless communication system according to claim 2, wherein the number of bits of the branch is equal to a least common multiple of the reciprocal of the code rate and the first number of bits. ### Claim 4 (depends on 1) The wireless communication system according to claim 1, wherein the number of bits of the symbol is equal to a multiple of the first number of bits. ### Claim 5 (depends on 2) The wireless communication system according to claim 2, wherein the number of bits of the symbol is equal to a multiple of the first number of bits. ### Claim 6 (depends on 3) The wireless communication system according to claim 3, wherein the number of bits of the symbol is equal to a multiple of the first number of bits. ### Claim 7 (depends on 1) The wireless communication system according to claim 1, wherein the number of bits of the symbol is equal to the first number of bits. ### Claim 8 (depends on 2) The wireless communication system according to claim 2, wherein the number of bits of the symbol is equal to the first number of bits. ### Claim 9 (depends on 3) The wireless communication system according to claim 3, wherein the number of bits of the symbol is equal to the first number of bits. ### Claim 10 A wireless communication device comprising: a transmitter comprising: a coder to generate a first bit sequence by performing convolutional coding on an information bit on the basis of a code rate; a bit eraser to generate a second bit sequence by erasing one or more bits from the first bit sequence for every predetermined first number of bits; and a modulator to generate a symbol by modulation using the second bit sequence; and a receiver comprising: a demodulator to calculate a plurality of first reliabilities that are reliabilities of a plurality of bit sequences that can be derived from the symbol; a likelihood extender to generate a plurality of extended bit sequences that are bit sequences each composed of bits for the first number of bits, and generate a plurality of second reliabilities that are reliabilities of the plurality of extended bit sequences by assigning a plurality of first reliabilities duplicated, as the reliabilities of the plurality of extended bit sequences; and a decoder to create a trellis diagram using the code rate and the plurality of extended bit sequences, and perform decoding by assigning the plurality of second reliabilities to a plurality of branches of the trellis diagram. ### Claim 11 A receiver comprising: a demodulator to calculate a plurality of first reliabilities that are reliabilities of a plurality of bit sequences that can be derived from the symbol transmitted by a transmitter including a coder to generate a first bit sequence by performing convolutional coding on an information bit on the basis of a code rate, a bit eraser to generate a second bit sequence by erasing one or more bits from the first bit sequence for every predetermined first number of bits, and a modulator to generate a transmission symbol by modulation using the second bit sequence; a likelihood extender to generate a plurality of extended bit sequences that are bit sequences each composed of bits for a predetermined number of bits, and generate a plurality of second reliabilities that are reliabilities of the plurality of extended bit sequences by assigning a plurality of first reliabilities duplicated, as the reliabilities of the plurality of extended bit sequences; and a decoder to create a trellis diagram using the plurality of extended bit sequences, and perform decoding by assigning the plurality of second reliabilities to a plurality of branches of the trellis diagram. ### Claim 12 A control circuit by which a transmitter and a receiver are controlled, the control circuit causing the transmitter to implement: a first step of generating a first bit sequence by performing convolutional coding on an information bit on the basis of a code rate; a second step of generating a second bit sequence by erasing one or more bits from the first bit sequence for every predetermined first number of bits; and a third step of generating a symbol by modulation using the second bit sequence, and the control circuit causing the receiver to implement: a fourth step of calculating a plurality of first reliabilities that are reliabilities of a plurality of bit sequences that can be derived from the symbol; a fifth step of generating a plurality of extended bit sequences that are bit sequences each composed of bits for the first number of bits, and generating a plurality of second reliabilities that are reliabilities of the plurality of extended bit sequences by assigning a plurality of first reliabilities duplicated, as the reliabilities of the plurality of extended bit sequences; and a sixth step of creating a trellis diagram using the code rate and the plurality of extended bit sequences, and performing decoding by assigning the plurality of second reliabilities to a plurality of branches of the trellis diagram. ### Claim 13 A non-transitory storage medium in which a program is stored, the program being configured to control a transmitter and a receiver, the program causing the transmitter to implement: a first step of generating a first bit sequence by performing convolutional coding on an information bit on the basis of a code rate; a second step of generating a second bit sequence by erasing one or more bits from the first bit sequence for every predetermined first number of bits; and a third step of generating a symbol by modulation using the second bit sequence, and the program causing the receiver to implement: a fourth step of calculating a plurality of first reliabilities that are reliabilities of a plurality of bit sequences that can be derived from the symbol; a fifth step of generating a plurality of extended bit sequences that are bit sequences each composed of bits for the first number of bits, and generating a plurality of second reliabilities that are reliabilities of the plurality of extended bit sequences by assigning a plurality of first reliabilities duplicated, as the reliabilities of the plurality of extended bit sequences; and a sixth step of creating a trellis diagram using the code rate and the plurality of extended bit sequences, and performing decoding by assigning the plurality of second reliabilities to a plurality of branches of the trellis diagram.