A system for a digital subscriber line (DSL) network with a DSL interface can operate with processing circuitry that can generate symbols in multicarrier communications with codewords for modulation of a parity check. The codewords can be aligned with symbol boundaries of the symbols in a continuous transmission of the multi-carrier communications. The processing circuitry reduces a number of parity bits by puncturing and a number of data bits for shortening of the codewords so that a codeword boundary is aligned with a symbol boundary for one or more symbols, or a transmission frame of symbols.

A system for a digital subscriber line (DSL) network with a DSL interface can operate with processing circuitry that can generate symbols in multicarrier communications with codewords for modulation of a parity check. The codewords can be aligned with symbol boundaries of the symbols in a continuous transmission of the multi-carrier communications. The processing circuitry reduces a number of parity bits by puncturing and a number of data bits for shortening of the codewords so that a codeword boundary is aligned with a symbol boundary for one or more symbols, or a transmission frame of symbols.

In a transmitter, first and second sets of discrete multitone (DMT) sub-carrier signals or tones are identified. First and second bit groups of a payload data frame corresponding to the first and second sets of tones are selected. The first bit group is then trellis encoded. The second bit group is not trellis encoded. The first trellis coded tone group and the second bit group are then constellation mapped to produce a DMT symbol for transmission. A receiver may use an estimate of signal-to-noise ratio (SNR) of each tone to determine whether to select the tone for inclusion in the first or second set of tones. The receiver may provide the transmitter with information indicating whether a tone is included the first or second set of tones.

In a transmitter, first and second sets of discrete multitone (DMT) sub-carrier signals or tones are identified. First and second bit groups of a payload data frame corresponding to the first and second sets of tones are selected. The first bit group is then trellis encoded. The second bit group is not trellis encoded. The first trellis coded tone group and the second bit group are then constellation mapped to produce a DMT symbol for transmission. A receiver may use an estimate of signal-to-noise ratio (SNR) of each tone to determine whether to select the tone for inclusion in the first or second set of tones. The receiver may provide the transmitter with information indicating whether a tone is included the first or second set of tones.