System and method for transmitting a low density parity check signal

1. A method for low density parity check (LDPC) encoding, comprising:

at a transmitting device, based on a number of information bits to be delivered in a packet, determining an initial number of orthogonal frequency division multiplexing (OFDM) symbols;

determining a space time block coding (STBC) value; and

determining a number of extra symbols value based on said initial number of OFDM symbols, wherein a final number of OFDM symbols is based on said initial number of OFDM symbols and said number of extra symbols value;

generating an LDPC extension value based on said STBC value and said number of extra symbols value for purposes of determining LDPC parameters associated with said packet;

encoding said LDPC extension value in a header of said packet,

wherein when said STBC value is 0 and said number of extra symbols value is 0, then said LDPC extension value is 0;

wherein when said STBC value is 0 and said number of extra symbols value is 1, then said LDPC extension value is 1;

wherein when said STBC value is 1 and said number of extra symbols value is 0, then said LDPC extension value is 0; and

wherein when said STBC value is 1 and said number of extra symbols value is 2, then said LDPC extension value is 1;

at a receiving device, when said LDPC extension value is 1,

determining said number of extra symbols value is 1 when said STBC value is 0; and

determining said number of extra symbols value is 2 when said STBC value is 1.

2. The method of claim 1 , wherein said determining said number of extra symbols value comprises:

performing shortening and puncturing operations to determine said final number of OFDM symbols; and

signaling said final number of OFDM symbols in said packet.

3. The method of claim 1 , further comprising:

at said receiving device, receiving said packet from said transmitting device;

parsing said LDPC extension value from said header of said packet;

parsing said final number of OFDM symbols from a signal field of said packet;

determining said number of extra symbols value based on said STBC value and said LDPC extension value; and

determining said initial number of OFDM symbols based on said LDPC extension value and said final number of OFDM symbols.

4. The method of claim 1 , wherein said packet is in compliance with an IEEE 802.11 ac standard or its derivatives.

5. The method of claim 1 , further comprising:

wherein said final number of OFDM symbols is an integer value; and

wherein a number of code words is an integer value.

6. The method of claim 1 , further comprising:

at said transmitting device, maximizing MAC padding to a maximum number of bytes to ensure one-to-one mapping between said initial number of OFDM symbols and a number of bits in a data structure (Npld).

7. A device handling a packet of information, wherein said packet comprises:

a number of orthogonal frequency division multiplexing (OFDM) symbols (Nsym) value;

a space time block coding (STBC) value;

a number of extra symbols for low density parity check (LDPC) parameter determination associated with said packet (Nldpc_ext) value based on said STBC value and a number of extra symbols (Nsym_ext) value determined for said packet based on an initial number of OFDM symbols (Nsym_init),

wherein when said STBC value is 0 and said Nsym_ext value is 0, then said Nldpc_ext value is 0;

wherein when said STBC value is 0 and said Nsym_ext value is 1, then said Nldpc_ext value is 1;

wherein when said STBC value is 1 and said Nsym_ext value is 0, then said Nldpc_ext value is 0; and

wherein when said STBC value is 1 and said Nsym_ext value is 2, then said Nldpc_ext value is 1.

8. The device of claim 7 , wherein said packet is in compliance with an IEEE 802.11 ac standard or its derivatives.

9. A device for interpreting a packet of information, wherein said packet comprises:

a number of orthogonal frequency division multiplexing (OFDM) symbols (Nsym) value; and

a space time block coding (STBC) value;

wherein when a number of extra symbols for low density parity check (LDPC) parameter determination associated with said packet (Nldpc_ext) value, based on said STBC value and a number of extra symbols (Nsym_ext) value, is 1 for said packet,

when said STBC value is 0, then said Nsym_ext value is 1, and

when said STBC value is 1, then said Nsym_ext value is 2.

10. A system for low density parity check (LDPC) encoding, comprising:

at a transmitting device, an LDPC encoder for determining an initial number of orthogonal frequency division multiplexing (OFDM) symbols (Nsym_init) value based on a number of information bits to be delivered in a packet, wherein said LDPC encoder determines a number of extra symbols (Nsym_ext) value based on said Nsym_init value, wherein an Nsym value is based on said Nsym_init value and said Nsym_ext value; and

at said transmitting device, an extension calculator for generating a number of extra symbols for LDPC parameter determination associated with said packet (Nldpc_ext) value based on a space time block coding (STBC) value and said Nsym_ext value,

wherein said LDPC encoder at said transmitting device encodes said Nldpc_ext value in a header of said packet;

wherein when said STBC value is 0 and said Nsym_ext value is 0, then said Nldpc_ext value is 0;

wherein when said STBC value is 0 and said Nsym_ext value is 1, then said Nldpc_ext value is 1;

wherein when said STBC value is 1 and said Nsym_ext value is 0, then said Nldpc_ext value is 0; and

wherein when said STBC value is 1 and said Nsym_ext value is 2, then said Nldpc_ext value is 1;

at a receiving device configured to receive said packet from said transmitting device, a parser for parsing said Nldpc_ext value from said header of said packet, and for parsing said Nsym value from a signal field of said packet; and

at said receiving device, an LDPC decoder for determining said Nsym_ext value based on said STBC value and said Nldpc_ext value and for determining said Nsym_init value based on said Nldpc_ext value and said Nsym value, wherein at said receiving device, said LDPC decoder determines that said Nsym_ext value is 1 when said Nldpc_ext value is 1 and said STBC value is 0; and said LDPC decoder determines that said Nsym_ext value is 2 when said Nldpc_ext value is 1 and said STBC value is 1.

11. The system of claim 10 , wherein said LDPC encoder performs shortening and puncturing operations to determine said Nsym_ext value, and signals said Nsym value in said packet.

12. The system of claim 10 , wherein said extension calculator assigns said Nldpc_ext value to 1;

wherein when said STBC value is 0, then said Nsym_ext value is 1; and

wherein when said STBC value is 1, then said Nsym_ext value is 2.

13. The system of claim 10 , further comprising:

at said transmitting device, a MAC padder that maximizes MAC padding to a maximum number of bytes to ensure one-to-one mapping between said Nsym_init value and a number of bits in a data structure (Npld).