Very short size LDPC coding for physical and/or control channel signaling
View Patent ↗A communication device is configured to encode and/or decode low density parity check (LDPC) coded signals. Such LDPC coded signals are characterized by LDPC matrices having a particular form. An LDPC matrix may be partitioned into a left hand side matrix and the right hand side matrix. The right hand side matrix can be lower triangular such that all of the sub-matrices therein are all-zero-valued sub-matrices (e.g., all of the elements within an all-zero-valued sub-matrix have the value of “0”) except for those sub-matrices located on a main diagonal of the right hand side matrix and another diagonal that is adjacently located to the left of the main diagonal. A device may be configured to employ different LDPC codes having different LDPC matrices for different LDPC coded signals. The different LDPC matrices may be based generally on a common form (e.g., with a right hand side matrix as described above).
1. A communication device comprising:
a communication interface; and
a processor, at least one of the processor or the communication interface configured to:
encode information bits using a low density parity check (LDPC) code to generate coded bits, wherein the LDPC code is characterized by an LDPC matrix that includes a plurality of sub-matrices arranged in a left hand side matrix and a right hand side matrix, wherein the right hand side matrix is lower triangular and includes all-zero-valued sub-matrices except for CSI (Cyclic Shifted Identity) sub-matrices located on a main diagonal of the right hand side matrix and another diagonal that is adjacently located to a left of the main diagonal; and
puncture a subset of the information bits and a subset of parity bits from the coded bits to generate a codeword; and
transmit a signal that includes the codeword to another communication device via a communication channel.
2. The communication device of claim 1 , wherein the at least one of the processor or the communication interface is further configured to:
add a plurality of zero-valued fill bits to the information bits before encoding using the LDPC code; and
shorten the plurality of zero-valued fill bits from the coded bits before puncturing the subset of the information bits and the subset of parity bits.
3. The communication device of claim 1 , wherein the at least one of the processor or the communication interface is further configured to:
transmit the signal via a Physical Layer (PHY) Link Control (PLC) sub-channel used for ranging or a Next Codeword Pointer (NCP) sub-channel used for locating at least one additional codeword, wherein the communication channel includes the PLC sub-channel and the NCP sub-channel.
4. The communication device of claim 1 , wherein the at least one of the processor or the communication interface is further configured to:
add a plurality of zero-valued fill bits to other information bits to generate filled bits;
encode the filled bits using another LDPC code to generate other coded bits;
shorten the plurality of zero-valued fill bits from the other coded bits; and
puncture a subset of information bits and a subset of parity bits from the other coded bits to generate another codeword;
transmit the signal via a Physical Layer (PHY) Link Control (PLC) sub-channel of the communication channel; and
transmit another signal that includes the other codeword to the ether another communication device via a Next Codeword Pointer (NCP) sub-channel of the communication channel.
5. The communication device of claim 1 , wherein the at least one of the processor or the communication interface is further configured to:
encode other information bits using an forward error correction (FEC) code to generate data bits; and
the communication interface configured to transmit another signal that includes the data bits to the another communication device via a data sub-channel of the communication channel.
6. The communication device of claim 1 , wherein the at least one of the processor or the communication interface is further configured to:
generate another codeword;
generate cyclic redundancy check (CRC) bits based on the codeword and the other codeword; and
transmit one or more signals that include the codeword, the other codeword, and the CRC bits to the another communication device via the communication channel.
7. The communication device of claim 1 further comprising:
a cable modem, wherein the another communication device is a cable headend transmitter or a cable modem termination system (CMTS).
8. The communication device of claim 1 , wherein the at least one of the processor or the communication interface is further configured to:
support communications within at least one of a satellite communication system, a wireless communication system, a wired communication system, a fiber-optic communication system, or a mobile communication system.
9. A communication device comprising:
a communication interface; and
a processor, at least one of the processor or the communication interface configured to:
encode first information bits using a first low density parity check (LDPC) code to generate first coded bits;
encode second information bits using a second LDPC code to generate second coded bits, wherein at least one of the first or second LDPC codes is characterized by an LDPC matrix that includes a plurality of sub-matrices arranged in a left hand side matrix and a right hand side matrix, wherein the right hand side matrix is lower triangular and includes all-zero-valued sub-matrices except for CSI (Cyclic Shifted Identity) sub-matrices located on a main diagonal of the right hand side matrix and another diagonal that is adjacently located to a left of the main diagonal; and
puncture a first subset of the first information bits and a first subset of parity bits from the first coded bits to generate a first codeword; and
puncture a second subset of the second information bits and a second subset of parity bits from the second coded bits to generate a second codeword; and
transmit a first signal that includes the first codeword to another communication device via a Physical Layer (PHY) Link Control (PLC) sub-channel of a communication channel; and
transmit a second signal that includes the second codeword to the another communication device via a Next Codeword Pointer (NCP) sub-channel of the communication channel.
10. The communication device of claim 9 , wherein the at least one of the processor or the communication interface is further configured to:
add a plurality of zero-valued fill bits to the second information bits before encoding using the second LDPC code; and
shorten the plurality of zero-valued fill bits from the second coded bits before puncturing the second subset of information bits and the second subset of parity bits.
11. The communication device of claim 9 , wherein the at least one of the processor or the communication interface is further configured to:
encode third information bits using an forward error correction (FEC) code to generate data bits; and
transmit another signal that includes the data bits to the another communication device via a data sub-channel of the communication channel.
12. The communication device of claim 9 further comprising:
a cable modem, wherein the another communication device is a cable headend transmitter or a cable modem termination system (CMTS).
13. The communication device of claim 9 , wherein the at least one of the processor or the communication interface is further configured to:
support communications within at least one of a satellite communication system, a wireless communication system, a wired communication system, a fiber-optic communication system, or a mobile communication system.
14. A method for execution by a communication device, the method comprising:
encoding information bits using a low density parity check (LDPC) code to generate coded bits, wherein the LDPC code is characterized by an LDPC matrix that includes a plurality of sub-matrices arranged in a left hand side matrix and a right hand side matrix, wherein the right hand side matrix is lower triangular and includes all-zero-valued sub-matrices except for CSI (Cyclic Shifted Identity) sub-matrices located on a main diagonal of the right hand side matrix and another diagonal that is adjacently located to a left of the main diagonal;
puncturing a subset of the information bits and a subset of parity bits from the coded bits to generate a codeword; and
via a communication interface of the communication device, transmitting a signal that includes the codeword to another communication device via a communication channel.
15. The method of claim 14 further comprising:
adding a plurality of zero-valued fill bits to the information bits before encoding using the LDPC code; and
shortening the plurality of zero-valued fill bits from the coded bits before puncturing the subset of the information bits and the subset of parity bits.
16. The method of claim 14 further comprising:
transmitting the signal via a Physical Layer (PHY) Link Control (PLC) sub-channel used for ranging or a Next Codeword Pointer (NCP) sub-channel used for locating at least one additional codeword, wherein the communication channel includes the PLC sub-channel and the NCP sub-channel.
17. The method of claim 14 further comprising:
encoding other information bits using an forward error correction (FEC) code to generate data bits; and
transmitting another signal that includes the data bits to the another communication device via a data sub-channel of the communication channel.
18. The method of claim 14 further comprising:
generating another codeword;
generating cyclic redundancy check (CRC) bits based on the codeword and the other codeword; and
transmitting one or more signals that include the codeword, the other codeword, and the CRC bits to the another communication device via the communication channel.
19. The method of claim 14 , wherein the communication device is a cable modem, and the another communication device is a cable headend transmitter or a cable modem termination system (CMTS).
20. The method of claim 14 further comprising:
operating the communication interface of the communication device to support communications within at least one of a satellite communication system, a wireless communication system, a wired communication system, a fiber-optic communication system, or a mobile communication system.