Granted Patent B2

US 7,899,124 · App. 11/855,215 · Granted Mar 1, 2011

Abstract

Claims (33)

1. A method of selectively modifying impulse noise protection in a communication system, comprising:

adding a number of redundancy bits to blocks of data to form codewords, where the number of redundancy bits is capable of correcting up to a pre-determined number of bit errors within each block of data, and where the number of redundancy bits is selected as a function of an initial impulse noise protection value;

separating the codewords into interleaver blocks and interleaving the interleaver blocks to form an interleaved data stream; and

selecting an interleaver depth such that one symbol corresponds to an integer number of bytes of the interleaved data stream.

2. The method of claim 1 , where a number of redundancy bytes per interleaver block is selected to be equal to a value of impulse noise protection per symbol.

3. The method of claim 1 , where a number of bytes per interleaver block is selected to be identical to a maximum interleaver delay per symbol.

4. The method of claim 1 , further comprising:

seamlessly adjusting impulse noise protection from the initial impulse noise protection value to a modified impulse noise protection value.

5. The method of claim 4 , where seamlessly adjusting impulse noise protection comprises:

selectively adapting only the number of redundancy bits.

6. The method of claim 4 , where seamlessly adjusting impulse noise protection comprises:

altering an effective number of correctable bytes per interleaver block.

7. The method of claim 4 , where seamlessly adjusting impulse noise protection comprises:

altering a number of correctable bytes per codeword.

8. The method of claim 4 , where seamlessly adjusting impulse noise protection comprises:

altering the integer number of bytes of the interleaver block.

9. The method of claim 1 , where the impulse noise protection value is selected as a function of a ratio between a maximum impulse noise protection value and a maximum number of correctible bytes per codeword.

10. A communication device configured to transfer a block of data over a communication line, comprising:

a forward error correction encoder configured to form a codeword by adding a number of redundancy bits to the block of data; and

an interleaver configured to form an interleaved data stream by dividing the codeword into a plurality of interleaver blocks and interleaving the interleaver blocks;

wherein the communication device is configured to frame the interleaved data stream as a series of symbols over the communication line, wherein one symbol is framed to correspond to an integer number of bytes of one of the plurality of interleaver blocks.

11. The communication device of claim 10 , further comprising:

an analyzer configured to monitor the interleaved data stream during communication service and to determine a number of corrupted symbols within a codeword span associated with the codeword.

12. The communication device of claim 11 , wherein the communication device is configured to selectively adapt an impulse noise protection value as a function of the number of corrupted symbols.

13. The communication device of claim 12 , wherein selectively adapting the impulse noise protection value comprises altering the number of redundancy bits.

14. The communication device of claim 12 , wherein while the impulse noise protection value is selectively adapted, at least one of an interleaver block size, an interleaver depth, and a number of bits loaded per symbol remain constant.

15. The communication device of claim 10 , where the communication device is a DSL modem.

16. A communication device comprising:

an analyzer for monitoring impulse noise on a transmission line during communication service;

a signal processor for forming codewords having redundancy bits and for interleaving the codewords to form an interleaved data stream;

wherein the signal processor is adapted to adjust impulse noise protection by changing only the number of redundancy bits associated with codewords; and

wherein the signal processor is adapted to selectively distribute an integer number of bytes of a codeword over one symbol; wherein a byte boundary of the codeword is aligned to a boundary of the symbol, or

wherein the signal processor is adapted to selectively distribute an integer number of bytes of an interleaver block over one symbol; wherein a byte boundary of the interleaver block is aligned to a boundary of the symbol.

Assignments (12)