Trellis interleaver and feedback precoder

1. A system for interleaving trellis codes, comprising:

a precoder state element configured to monitor a precoder state and to develop a series of precoder symbols;

an interleaver configured to receive and interleave the precoder symbols;

a trellis state element configured to receive the interleaved symbols and to develop a trellis state output; and

a trellis encoder configured to receive the trellis state output and to generate at least one redundant bit.

2. The system of claim 1 , further comprising a feedback precoder configured to maintain the magnitude of a transmit signal at a predefined level, wherein the precoder state is a state of the feedback precoder.

3. The system of claim 2 , wherein the precoder state defines changes in the transmit signal that occur as a result of feedback precoder actions.

4. The system of claim 1 , wherein the interleaver is configured to store the precoder symbols in a first sequence, and the trellis state element is configured to receive the precoder symbols from the interleaver in a second sequence.

5. The system of claim 1 , further comprising a constellation encoder configured to receive the redundant bit and at least one data bit and to generate a transmit signal based on the redundant bit and the data bit.

6. A modem that includes the system of claim 1 .

7. A method for interleaving trellis codes, comprising the steps of:

producing a series of precoder symbols;

interleaving the precoder symbols;

producing a trellis state output from the interleaved symbols; and

generating a redundant bit based upon the trellis state output.

8. The method of claim 7 , further comprising the step of:

maintaining a transmit signal magnitude at a predefined level.

9. The method of claim 8 , wherein the precoder state defines changes in the transmit signal that occur as a result of maintaining the transmit signal magnitude.

10. The method of claim 7 , further comprising the step of:

storing the precoder symbols in a first sequence; and

receiving the precoder symbols from the interleaver in a second sequence.

11. The method of claim 7 , further comprising the step of encoding a transmit signal using the redundant bit and at least one data bit.

12. A modem that implements the method of claim 7 .

13. A system for interleaving trellis codes, comprising:

means for producing a series of precoder symbols;

means for interleaving the precoder symbols;

means for producing a trellis state output from the interleaved symbols; and

means for generating a redundant bit based upon the trellis state output.

14. The system of claim 13 , further comprising a means for maintaining a transmit signal magnitude at a predefined level.

15. The system of claim 14 , wherein the precoder state defines changes in the transmit signal that occur as a result of actions by the means for maintaining the transmit signal magnitude.

16. The system of claim 13 , further comprising:

means for storing the precoder symbols in a first sequence; and

means for receiving the precoder symbols from the interleaver in a second sequence.

17. The system of claim 13 , further comprising means for encoding a transmit signal using the redundant bit and at least one data bit.

18. A modem that includes the system of claim 13 .

19. A system for interleaving trellis codes, comprising:

a precoder configured to receive a first constellation and to produce a precoder state associated with the first constellation;

a precoder state element configured to receive the precoder state and to produce a trellis symbol associated with a trellis state;

an interleaver configured to receive a first sequence of the trellis symbols and to produce a second sequence of the trellis symbols;

a trellis state element configured to receive the interleaved trellis symbols and to produce a trellis state for each of the interleaved symbols, where the trellis state is associated with the first constellation; and

a trellis encoder configured to receive the trellis state and to produce a redundant bit based on the trellis state.

20. The system of claim 19 , further comprising:

a constellation encoder configured to produce the first constellation based on the redundant bit.

21. The system of claim 19 , wherein the precoder is further configured to produce a second constellation with altered power characteristics.

22. A modem that includes the system of claim 19 .

23. A method for interleaving trellis codes in a data communications system comprising the steps of:

generating a trellis symbol representing a trellis state of a first signal constellation;

interleaving a plurality of the trellis symbols;

determining the trellis state associated with each of the trellis symbols; and

trellis encoding based on the trellis state to produce a redundant bit.

24. The method of claim 23 , further comprising the steps of:

precoding the first signal constellation to produce a second signal constellation; and

transmitting the second signal constellation.

25. The method of claim 23 , wherein the interleaving step further comprises:

receiving the plurality of trellis symbols in a first sequence; and

producing a second sequence of the plurality of trellis symbols.

26. The method of claim 23 , wherein the determining step further comprises:

slicing each of the trellis symbols to determine a vector y(n) associated with each of the trellis symbols.

27. A modem that implements the method of claim 23 .