Method, communication device, processing device, and storage medium for performing channel encoding, and method and communication device for performing channel decoding
A communication device: performs LBRM for storing, in a circular buffer having the length N_IR, N_IR coded bits from among coded bits obtained by performing encoding on the basis of a polar code; performs rate matching on coded bits stored in the circular buffer; and transmits the rate-matched coded bits to another communication device. The communication device stores, in the circular buffer, last N_IR bits from among the coded bits if a code rate is less than or equal to a predetermined value, and, if not, stores first N_IR bits in the circular buffer.
1 . A method performed by a communication device, the method comprising:
generating coded bits d_0, d_1, d_2, . . . , d_(N−1) by encoding an information block of length K based on a polar code of length N;
performing limited buffer rate matching (LBRM) to store N IR coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1) into a circular buffer of length N IR , where N is greater than N IR ;
performing rate matching on the N IR coded bits stored in the circular buffer to generate a rate matching output sequence of length E; and
transmitting the rate matching output sequence of length E,
wherein performing the rate matching on the N IR coded bits stored in the circular buffer comprises:
performing puncturing to exclude first (N IR −E) coded bits among the N IR coded bits stored in the circular buffer to generate the rate matching output sequence of length E, based on K/E being smaller than or equal to R and E being smaller than N IR ,
performing the rate matching comprises performing shortening to exclude last (N IR −E) coded bits among the N IR coded bits stored in the circular buffer to generate the rate matching output sequence of length E, based on K/E being greater than R and E being smaller than N IR , and
obtaining E coded bits by i) obtaining the N IR coded bits starting from a first coded bit among the N IR coded bits stored in the circular buffer and ii) cyclically repeating (E−N IR ) coded bits starting from the first coded bit among the N IR coded bits stored in the circular buffer, based on E being equal to greater than N IR .
2 . The method of claim 1 , comprising:
freezing bit indices corresponding to coded bits d_0 to d_(N−N IR −1) among the coded bits d_0, d_1, d_2, . . . , d_(N−1), among N input bit indices of the polar code, based on K/E being smaller than or equal to R.
3 . The method of claim 1 , comprising:
freezing bit indices corresponding to coded bits d_N IR to d_(N−1) among the coded bits d_0, d_1, d_2, . . . , d_(N−1), among N input bit indices of the polar code, based on K/E being greater than R.
4 . The method of claim 1 , wherein performing the LBRM to store the N IR coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1) into the circular buffer of length N IR comprises:
i) puncturing (N−N IR ) coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1) based on K/E being smaller than or equal to R; and
ii) shortening (N−N IR ) coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1) based on K/E being greater than R, where R is a predetermined value,
wherein puncturing the (N−N IR ) coded bits comprises excluding first (N−N IR ) coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1), and
wherein shortening the (N−N IR ) coded bits comprises excluding last (N−N IR ) coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1).
5 . A communication device comprising:
at least one transceiver;
at least one processor; and
at least one computer memory operably connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations comprising:
generating coded bits d_0, d_1, d_2, . . . , d_(N−1) by encoding an information block of length K based on a polar code of length N;
performing limited buffer rate matching (LBRM) to store N IR coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1) into a circular buffer of length N IR , where N is greater than N IR ;
performing rate matching on the N IR coded bits stored in the circular buffer to generate a rate matching output sequence of length E; and
transmitting the rate matching output sequence of length E,
wherein performing the rate matching on the N IR coded bits stored in the circular buffer comprises:
performing puncturing to exclude first (N IR −E) coded bits among the N IR coded bits stored in the circular buffer to generate the rate matching output sequence of length E, based on K/E being smaller than or equal to R and E being smaller than N IR ,
performing the rate matching comprises performing shortening to exclude last (N IR −E) coded bits among the N IR coded bits stored in the circular buffer to generate the rate matching output sequence of length E, based on K/E being greater than R and E being smaller than N IR , and
obtaining E coded bits by i) obtaining the N IR coded bits starting from a first coded bit among the N IR coded bits stored in the circular buffer and ii) cyclically repeating (E−N IR ) coded bits starting from the first coded bit among the N IR coded bits stored in the circular buffer, based on E being equal to greater than N IR .
6 . The communication device of claim 5 , wherein performing the LBRM to store the N IR coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1) into the circular buffer of length N IR comprises:
i) puncturing (N−N IR ) coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1) based on K/E being smaller than or equal to R; and
ii) shortening (N−N IR ) coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1) based on K/E being greater than R, where R is a predetermined value,
wherein puncturing the (N−N IR ) coded bits comprises excluding first (N−N IR ) coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1), and
wherein shortening the (N−N IR ) coded bits comprises excluding last (N−N IR ) coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1).
7 . The communication device of claim 5 , wherein the operations comprise:
freezing bit indices corresponding to coded bits d_0 to d_(N−N IR −1) among the coded bits d_0, d_1, d_2, . . . , d_(N−1), among N input bit indices of the polar code, based on K/E being smaller than or equal to R.
8 . The communication device of claim 5 , wherein the operations comprise:
freezing bit indices corresponding to coded bits d_N IR to d (N−1) among the coded bits d_0, d_1, d_2, . . . , d_(N−1), among N input bit indices of the polar code, based on K/E being greater than R.
9 . A communication device comprising:
at least one transceiver;
at least one processor; and
at least one computer memory operably connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations comprising:
receiving a rate matching output sequence of length E from another communication device;
determining N IR coded bits based on the rate matching output sequence of length E, where N IR is a length of a circular buffer of the other communication device;
determining coded bits d_0, d_1, d_2, . . . , d_(N−1) based on limited buffer rate matching (LBRM) and the N IR coded bits; and
decoding the coded bits d_0, d_1, d_2, . . . , d_(N−1) based on a polar code of length N to determine an information block of length K,
wherein the rate-matched sequence of length E is obtained by performing rate matching on the N IR coded bits stored in the circular buffer, and performing the rate matching on the N IR coded bits stored in the circular buffer comprises:
performing puncturing to exclude first (N IR −E) coded bits among the N IR coded bits stored in the circular buffer to generate the rate matching output sequence of length E, based on K/E being smaller than or equal to R and E being smaller than N IR ,
performing the rate matching comprises performing shortening to exclude last (N IR −E) coded bits among the N IR coded bits stored in the circular buffer to generate the rate matching output sequence of length E, based on K/E being greater than R and E being smaller than N IR , and
obtaining E coded bits by i) obtaining the N IR coded bits starting from a first coded bit among the N IR coded bits stored in the circular buffer and ii) cyclically repeating (E−N IR ) coded bits starting from the first coded bit among the N IR coded bits stored in the circular buffer, based on E being equal to greater than N IR .
10 . The communication device of claim 9 , wherein the LBRM is performed to store the N IR coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1) into the circular buffer of length N IR , and the LBRM comprises:
i) puncturing (N−N IR ) coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1) based on K/E being smaller than or equal to R; and
ii) shortening (N−N IR ) coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1) based on K/E being greater than R, where R is a predetermined value,
wherein puncturing the (N−N IR ) coded bits comprises excluding first (N−N IR ) coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1), and
wherein shortening the (N−N IR ) coded bits comprises excluding last (N−N IR ) coded bits among the coded bits d_0, d_1, d_2, . . . , d_(N−1).