Boundary identification for probabilistic amplitude shaping
This disclosure provides methods, devices and systems for amplitude shaping encoding, and specifically, for indicating boundaries in bitstreams encoded using amplitude shaping encoding. In some aspects, a transmitting device may insert, into an bitstream to indicate a boundary, a sequence of amplitude bits not associated with any patterns of bit values in a lookup table used for the encoding. In some other aspects, a transmitting device may monitor a length of the amplitude bits in a bitstream during the encoding and stop the encoding on information bits at an end of a current data unit responsive to the length reaching a threshold. In some other aspects, a transmitting device may monitor the length of the information bits and, for each data unit, determine whether a boundary is or would be reached. Responsive to determining that a boundary is or would be reached, the transmitting device may not include, before the boundary, any amplitude bits generated based on the information bits in the data unit, and instead add padding bits after a last amplitude bit before the boundary.
1. A method for wireless communication by a wireless communication device, the method comprising:
receiving a wireless packet that includes a plurality of symbols associated with a plurality of data units, each symbol of the received plurality of symbols having an associated symbol amplitude of a set of possible symbol amplitudes, each symbol amplitude of the set of possible symbol amplitudes being associated with a respective sequence of amplitude bits of a set of possible sequences of amplitude bits, each sequence of amplitude bits of a subset of sequences of amplitude bits of the set of possible sequences of amplitude bits being associated with a respective pattern of bit values of a set of possible patterns of bit values associated with a prefix encoding operation, each sequence of amplitude bits of the set of possible sequences of amplitude bits that is not associated with any pattern of bit values of the set of possible patterns of bit values being associated with a boundary such that any sequence of amplitude bits, of the sequences of amplitude bits associated with the symbol amplitudes of the received plurality of symbols, that is not associated with any pattern of bit values of the set of possible patterns of bit values indicates a respective boundary between a respective pair of adjacent data units of the plurality of data units;
performing a prefix decoding operation on the sequences of amplitude bits associated with the symbol amplitudes of the received plurality of symbols after removing any sequences of amplitude bits, of the sequences of amplitude bits associated with the symbol amplitudes of the received plurality of symbols, that are not associated with any pattern of bit values of the set of possible patterns of bit values; and
processing information bits generated by the performance of the prefix decoding operation in accordance with the respective boundaries indicated by any sequences of amplitude bits, of the sequences of amplitude bits associated with the symbol amplitudes of the received plurality of symbols, that are not associated with any pattern of bit values of the set of possible patterns of bit values.
2. The method of claim 1 , wherein each data unit of the plurality of data units corresponds to a Medium Access Control (MAC) protocol data unit (MPDU), a group of multiple bytes of information bits of multiple groups of information bits within a single MPDU, or a group of information bits corresponding to an integer number of orthogonal frequency division multiplexing (OFDM) symbols.
3. The method of claim 1 , wherein the prefix encoding operation is a probabilistic amplitude shaping operation.
4. The method of claim 1 , further comprising performing a low density parity check (LDPC) decoding operation on the sequences of amplitude bits prior to performing the prefix decoding operation on the sequences of amplitude bits.
5. The method of claim 1 , wherein the set of possible patterns of bit values is associated with a probability mass function associated with the prefix encoding operation.
6. A wireless communication device, comprising:
one or more processors; and
one or more memories coupled with the one or more processors and storing processor-readable code that, when executed by the one or more processors, is configured to cause the wireless communication device to:
receive a wireless packet that includes a plurality of symbols associated with a plurality of data units, each symbol of the received plurality of symbols having an associated symbol amplitude of a set of possible symbol amplitudes, each symbol amplitude of the set of possible symbol amplitudes being associated with a respective sequence of amplitude bits of a set of possible sequences of amplitude bits, each sequence of amplitude bits of a subset of sequences of amplitude bits of the set of possible sequences of amplitude bits being associated with a respective pattern of bit values of a set of possible patterns of bit values associated with a prefix encoding operation, each sequence of amplitude bits of the set of possible sequences of amplitude bits that is not associated with any pattern of bit values of the set of possible patterns of bit values being associated with a boundary such that any sequence of amplitude bits, of the sequences of amplitude bits associated with the symbol amplitudes of the received plurality of symbols, that is not associated with any pattern of bit values of the set of possible patterns of bit values indicates a respective boundary between a respective pair of adjacent data units of the plurality of data units;
perform a prefix decoding operation on the sequences of amplitude bits associated with the symbol amplitudes of the received plurality of symbols after removing any sequences of amplitude bits, of the sequences of amplitude bits associated with the symbol amplitudes of the received plurality of symbols, that are not associated with any pattern of bit values of the set of possible patterns of bit values; and
process information bits generated by the performance of the prefix decoding operation in accordance with the respective boundaries indicated by any sequences of amplitude bits, of the sequences of amplitude bits associated with the symbol amplitudes of the received plurality of symbols, that are not associated with any pattern of bit values of the set of possible patterns of bit values.
7. The wireless communication device of claim 6 , wherein each data unit of the plurality of data units corresponds to a Medium Access Control (MAC) protocol data unit (MPDU), a group of multiple bytes of information bits of multiple groups of information bits within a single MPDU, or a group of information bits corresponding to an integer number of orthogonal frequency division multiplexing (OFDM) symbols.
8. The wireless communication device of claim 6 , wherein the prefix encoding operation is a probabilistic amplitude shaping operation.
9. The wireless communication device of claim 6 , wherein the code, when executed by the one or more processors, is further configured to cause the wireless communication device to perform a low density parity check (LDPC) decoding operation on the sequences of amplitude bits prior to performing the prefix decoding operation on the sequences of amplitude bits.
10. The wireless communication device of claim 6 , wherein the set of possible patterns of bit values is associated with a probability mass function associated with the prefix encoding operation.
11. A method for wireless communication by a wireless communication device, the method comprising:
performing a prefix encoding operation on a plurality of data units, each data unit including information bits, the performance of the prefix encoding operation including comparing sequences of consecutive bits of the information bits to one or more patterns of bit values of a set of possible patterns of bit values associated with the prefix encoding operation, each pattern of bit values of the set of possible patterns of bit values being associated with a respective sequence of amplitude bits of a set of possible sequences of amplitude bits, each sequence of amplitude bits of the set of possible sequences of amplitude bits being associated with a respective symbol amplitude of a set of possible symbol amplitudes;
inserting, at a boundary between adjacent data units of the plurality of data units, a sequence of amplitude bits of the set of possible sequences of amplitude bits that is not associated with any pattern of bit values of the set of possible patterns of bit values, the inserted sequence of amplitude bits indicating the boundary; and
transmitting a wireless packet that includes a plurality of symbols having respective symbol amplitudes associated with the sequences of amplitude bits generated by the performance of the prefix encoding operation and the sequence of amplitude bits indicating the boundary.
12. The method of claim 11 , wherein each data unit of the plurality of data units corresponds to a Medium Access Control (MAC) protocol data unit (MPDU), a group of multiple bytes of information bits of multiple groups of information bits within a single MPDU, or a group of information bits corresponding to an integer number of orthogonal frequency division multiplexing (OFDM) symbols.
13. The method of claim 11 , wherein the prefix encoding operation is a probabilistic amplitude shaping operation.
14. The method of claim 11 , further comprising performing a low density parity check (LDPC) encoding operation on the sequences of amplitude bits generated by the performance of the prefix encoding operation.
15. The method of claim 11 , wherein the set of possible patterns of bit values is associated with a probability mass function associated with the prefix encoding operation.
16. A wireless communication device, comprising:
one or more processors; and
one or more memories coupled with the one or more processors and storing processor-readable code that, when executed by the one or more processors, is configured to cause the wireless communication device to:
perform a prefix encoding operation on a plurality of data units, each data unit including information bits, the performance of the prefix encoding operation including comparing sequences of consecutive bits of the information bits to one or more patterns of bit values of a set of possible patterns of bit values associated with the prefix encoding operation, each pattern of bit values of the set of possible patterns of bit values being associated with a respective sequence of amplitude bits of a set of possible sequences of amplitude bits, each sequence of amplitude bits of the set of possible sequences of amplitude bits being associated with a respective symbol amplitude of a set of possible symbol amplitudes;
insert, at a boundary between adjacent data units of the plurality of data units, a sequence of amplitude bits of the set of possible sequences of amplitude bits that is not associated with any pattern of bit values of the set of possible patterns of bit values, the inserted sequence of amplitude bits indicating the boundary; and
transmit a wireless packet that includes a plurality of symbols having respective symbol amplitudes associated with the sequences of amplitude bits generated by the performance of the prefix encoding operation and the sequence of amplitude bits indicating the boundary.
17. The wireless communication device of claim 16 , wherein each data unit of the plurality of data units corresponds to a Medium Access Control (MAC) protocol data unit (MPDU), a group of multiple bytes of information bits of multiple groups of information bits within a single MPDU, or a group of information bits corresponding to an integer number of orthogonal frequency division multiplexing (OFDM) symbols.
18. The wireless communication device of claim 16 , wherein the prefix encoding operation is a probabilistic amplitude shaping operation.
19. The wireless communication device of claim 16 , wherein the code, when executed by the one or more processors, is further configured to cause the wireless communication device to perform a low density parity check (LDPC) encoding operation on the sequences of amplitude bits generated by the performance of the prefix encoding operation.
20. The wireless communication device of claim 16 , wherein the set of possible patterns of bit values is associated with a probability mass function associated with the prefix encoding operation.