Trellis encoder and decoder based upon punctured rate 1/2 convolutional codes

A method for decoding interleaved trellis modulated data comprising the steps of:

• receiving and decoding, in accordance with a first decoding format, said interleaved trellis modulated data to provide sets of three symbols;
• delaying for a predetermined first duration a first symbol of each set of three symbols;
• delaying for a predetermined second duration a second symbol of each set of three symbols;
• combining delayed first and second symbols with third symbols of said sets of three symbols to provide a set of n symbols;
• and
• decoding according to a decoding format said set of n symbols.

An apparatus for encoding data, comprising:

• encoding means for receiving user data and encoding said user data into a first number of encoded symbol streams;
• symbol grouping means for converting said first number of encoded symbol streams into a different second number of reordered encoded symbol streams, said symbol grouping means comprising a plurality of delay means wherein each of said plurality of delay means delays ones of said second number of reordered encoded symbol streams by different delays;
• and
• transmitter means for receiving successive sets of encoded symbols provided by said second number of reordered encoded symbol streams, and for modulating and transmitting said successive sets of encoded symbols in accordance with a predetermined encoding format.

A method for encoding data, comprising the steps of:

• receiving user data;
• encoding said user data in accordance with a predetermined coding format to provide a first number of encoded symbol streams;
• converting said first number of encoded symbol streams into a different second number of reordered encoded symbol streams, the step of converting further including the step of delaying ones of said second number of reordered encoded symbol streams by different delays;
• and
• transmitting symbol sets provided by said second number of reordered encoded symbol streams in accordance with a predetermined encoding format.

A system for encoding data, comprising:

• an encoder having an input for receiving user data and encoding said user data in accordance with a first predetermined coding format and having an output for providing encoded symbols;
• a symbol buffer having an input coupled to said encoder output for reordering said encoded symbols in accordance with a predetermined grouping format and having an output, said symbol buffer comprising a plurality of delay elements wherein each of said plurality of delay elements delays ones of said encoded symbols by different delays;
• and
• a transmitter having an input coupled to said symbol buffer output for modulating and transmitting sets of said reordered encoded symbols, said sets of said reordered encoded symbols each being mapped to a modulation value in accordance with a second predetermined coding format.

An apparatus for decoding data, comprising:

• demodulator means for receiving a transmitted signal and for demodulating said transmitted signal in accordance with a predetermined demodulation format to provide a first number of streams of symbol estimates;
• symbol grouping means for converting said first number of streams of symbol estimates into a different second number of streams of reordered symbol estimates, said symbol means comprising a plurality of delay means wherein each of said plurality of delay means delays ones of said first number of streams of symbol estimates by different delays;
• and
• decoder means for decoding symbol sets provided by said second number of streams of reordered symbol estimates.

A method for decoding data, comprising the steps of:

• receiving a transmitted signal;
• demodulating said transmitted signal in accordance with a predetermined demodulation format to provide a first number of streams of symbol estimates;
• converting said first number of streams of symbol estimates into a different second number of streams of reordered symbol estimates, said step of converting including the step of delaying ones of said first number of streams of symbol estimates by different delays;
• and
• decoding symbol sets provided by said second number of streams of reordered symbols estimates.

A system for decoding data, comprising:

• a demodulator having an input for receiving a transmitted signal and for demodulating said transmitted signal in accordance with a predetermined demodulation format and having an output to provide sets of symbol estimates, each of said sets of symbol estimates being associated with a modulation value based upon said predetermined demodulation format;
• a symbol buffer having an input coupled to said demodulator output, for reordering said sets of symbol estimates in accordance with a predetermined grouping format and having an output for providing sets of reordered symbol estimates, said symbol buffer comprising a plurality of delay elements wherein each of said plurality of delay elements delays ones of said symbol estimates within each of said sets of symbol estimates by different delay durations;
• and
• a decoder having an input coupled to said symbol buffer output for decoding said sets of reordered symbol estimates in accordance with a predetermined decoding format.

A system for encoding digital data for trellis modulation comprising:

• first means for receiving k input data bits;
• second means for encoding said k input data bits according to a first encoding format to provide n symbols;
• third means for converting said n symbols to provide said n symbols as a sequence of sets of at least three symbols;
• fourth means for delaying for a predetermined first duration a second symbol of each set of three symbols;
• fifth means for delaying for a predetermined second duration a third symbol of each set of three symbols;
• and
• sixth means for providing an interleaved symbol set including a first symbol of one of said sets of symbols with corresponding delayed second and third symbols of previous symbol sets.

A system for decoding interleaved trellis modulated data comprising:

• first means for receiving and decoding said interleaved trellis modulated data to provide sets of three symbols;
• second means for delaying for a predetermined first duration a first symbol of each set of three symbols;
• third means for delaying for a predetermined second duration a second symbol of each set of three symbols;
• fourth means for combining delayed first and second symbols with third symbols of said sets of three symbols to provide a set of n symbols;
• and
• fifth means for decoding according to a decoding format said set of n symbols.