Multi-channel parallel/serial concatenated convolutional codes and trellis coded modulation encoder/decoder

A method for encoding data for transmission in a multichannel network, comprising the steps of:

• a. measuring a transmission characteristic of a said first channel of said multichannel network;
• b. measuring a transmission characteristic of a second channel of said multichannel network;
• c. encoding an information data stream to generate a parity bit stream;
• d. selecting a portion of said parity bit stream for transmission in said first channel responsively to a result of said steps a and b.

A method for transmitting turbo-encoded data in a multitone channel having multiple subchannels, comprising the steps of.

• calculating a lowest signal-to-noise ratio corresponding to each of number of information bits to be transmitted in each of said subchannels;
• storing a result of said step of calculating in a memory,
• encoding a data stream to generate a stream of parity bits;
• and
• transmitting a portion of said parity bits responsively to said result of said step of calculating.

A modem for communicating over a network having channels, comprising:

• a multichannel modulator connected to generate a respective symbol representing bits applied to said multichannel modulator on each of said channels;
• a controller;
• a turbo-encoder having first and second Recursive Systematic Convolutional encoders (RSC encoders) receiving data from an input data source and connected to apply to said multichannel modulator first parity bits from said first RSC encoder and second parity bits from said second RSC encoder under control of said controller;
• said controller having a memory for storing measured respective transmission characteristics of said channels;
• said controller being programmed to apply said information bits and only a portion of said first and second parity bits to said multichannel modulator responsively to said measured said respective transmission characteristics of said channels.

A method for allocating parity and information bits to bins, each bin corresponding to a respective channel of a multichannel communications link, comprising the steps of:

• preparing a list of signal-to-noise ratio data indicating the lowest signal-to-noise ratio and constellation size required to send a given number of information bits for a simulated channel;
• determining a respective channel characteristic of each of said channels;
• allocating a number of information bits for a first of said bins responsively to said list and said respective channel characteristic corresponding to said first of said bins;
• allocating a number of information bits for a second of said bins responsively to said list and said respective channel characteristic corresponding to said second of said bins.

A method for allocating information bits and first and second parity bits to bins, each bin corresponding to a respective channel of a multichannel communications link said first parity bits being generated by a first encoder and said second parity bits being generated by a second decoder, said second decoder receiving an interleaved version of an input data stream applied to said first encoder, said method comprising the steps of:

• preparing a list of signal-to-noise ratio data indicating the lowest signal-to-noise ratio and constellation size required to send a given number of information bits for a simulated channel;
• determining a respective channel characteristic of each of said channels;
• allocating at least one respective information bit of said information bits to each of said bins responsively to said list and said respective channel characteristic corresponding to said first of said bins;
• allocating said first and second parity bits among said bins such that the number of first parity bits allocated to all bins is substantially the same as the number of second parity bits.