Method for efficient packet framing in a communication network
Techniques to reduce the transmission overheads in a communication system are disclosed. In an embodiment, a method described herein relates to the elimination of redundant padding to realize an integer number of FEC code-words during the FEC-encoding process of transmission as well as the reduction/elimination of redundant padding to realize an integer number of transmission symbols during the subcarrier modulation mapping process of transmitting OFDM/ACMT/DMT symbols. The techniques are described in the context of a communication system based on the MoCA specification. Furthermore, techniques for channel-profiling, channel-estimation and bandwidth request/grant signaling that facilitate the realization of the method of reduction of transmission overheads in a MoCA system are also described.
1. A method, the method comprising:
encoding a data payload into a plurality of codewords using a hardware processor that is operable to execute a sequence of instructions stored in a memory;
for each codeword of the plurality of codewords:
selecting a corresponding multi-tone symbol from a plurality of multi-tone symbols, wherein the selection is according to a size of each of the plurality of codewords; and
modulating each of the plurality of codewords according to the corresponding multi-tone symbol; and
determining a signal-to-noise ratio for a last codeword of the plurality of codewords by interpolating corresponding signal-to-noise ratios for codewords of the plurality of codewords other than the last codeword of the plurality of codewords.
2. The method of claim 1 , wherein the plurality of codewords is a plurality of Forward Error Correction (FEC) codewords.
3. The method of claim 1 , wherein the plurality of multi-tone symbols is a plurality of adaptive constellation multi-tone (ACMT) symbols.
4. The method of claim 1 , wherein the method comprises communicating the plurality of multi-tone modulated codewords over a Multimedia Over Coax Alliance (MoCA) network.
5. The method of claim 1 , wherein a corresponding multi-tone symbol for a first codeword of the plurality of codewords is different than a corresponding multi-tone symbol for a last codeword of the plurality of codewords.
6. The method of claim 1 , wherein the method comprises adding a pad to a last codeword of the plurality of codewords.
7. The method of claim 1 , wherein the method comprises adding a pad to a portion of the data payload prior to encoding.
8. The method of claim 1 , wherein each codeword of the plurality of codewords comprises parity.
9. The method of claim 1 , wherein a corresponding multi-tone symbol for a last codeword of the plurality of codewords comprises a variable number of tones.
10. A system, the system comprising:
an encoder operable to encode a data payload into a plurality of codewords;
a modulator operable to modulate each codeword of the plurality of codewords according to a corresponding multi-tone symbol from a plurality of multi-tone symbols, wherein a selection of the corresponding multi-tone symbol is according to a size of each of the plurality of codewords; and
a receiver operable to determine a signal-to-noise ratio for a last codeword of the plurality of codewords by interpolating corresponding signal-to-noise ratios for codewords of the plurality of codewords other than the last codeword of the plurality of codewords.
11. The system of claim 10 , wherein the plurality of codewords is a plurality of Forward Error Correction (FEC) codewords.
12. The system of claim 10 , wherein the plurality of multi-tone symbols is a plurality of adaptive constellation multi-tone (ACMT) symbols.
13. The system of claim 10 , wherein the system comprises a transmitter operable to communicate the plurality of multi-tone modulated codewords over a Multimedia Over Coax Alliance (MoCA) network.
14. The system of claim 10 , wherein a corresponding multi-tone symbol for a first codeword of the plurality of codewords is different than a corresponding multi-tone symbol for a last codeword of the plurality of codewords.
15. The system of claim 10 , wherein the encoder is operable to add a pad to a last codeword of the plurality of codewords.
16. The system of claim 10 , wherein the encoder is operable to add a pad to a portion of the data payload prior to encoding.
17. The system of claim 10 , wherein each codeword of the plurality of codewords comprises parity.
18. The system of claim 10 , wherein a corresponding multi-tone symbol for a last codeword of the plurality of codewords comprises a variable number of tones.