Abstract: Residual FEXT resulting from intended and/or inherent partial cancellation of crosstalk in vectored DSL systems impairs upstream power back-off (UPBO) as traditionally implemented. By considering and taking into account the effects of residual crosstalk on vectored DSL system performance and operation, improved data rates and/or other vectored DSL system performance are realized through the use of UPBO parameters generated for a given residual FEXT environment.

Abstract: Residual FEXT resulting from intended and/or inherent partial cancellation of crosstalk in vectored DSL systems impairs upstream power back-off (UPBO) as traditionally implemented. By considering and taking into account the effects of residual crosstalk on vectored DSL system performance and operation, improved data rates and/or other vectored DSL system performance are realized through the use of UPBO parameters generated for a given residual FEXT environment.

Abstract: Improved techniques for acquiring symbol boundary timing at a receiver of a multicarrier data transmission system during a training sequence are disclosed. One aspect is symbol boundary determination at a receiver wherein minimal interference is used as a criterion in selecting from a plurality of potential symbol boundary timings. The symbol boundary determination at the receiver can be performed in a time domain or a frequency domain manner. Another aspect pertains to an improved training sequence wherein pairs of identical symbols are transmitted by a transmitter. These symbols can be supplied to the transmitter in a time domain or a frequency domain manner.

Abstract: Improved techniques for acquiring symbol boundary timing at a receiver of a multicarrier data transmission system during a training sequence are disclosed. One aspect is symbol boundary determination at a receiver wherein minimal interference is used as a criterion in selecting from a plurality of potential symbol boundary timings. The symbol boundary determination at the receiver can be performed in a time domain or a frequency domain manner. Another aspect pertains to an improved training sequence wherein pairs of identical symbols are transmitted by a transmitter. These symbols can be supplied to the transmitter in a time domain or a frequency domain manner.

Abstract: Residual FEXT resulting from intended and/or inherent partial cancellation of crosstalk in vectored DSL systems impairs upstream power back-off (UPBO) as traditionally implemented. By considering and taking into account the effects of residual crosstalk on vectored DSL system performance and operation, improved data rates and/or other vectored DSL system performance are realized through the use of UPBO parameters generated for a given residual FEXT environment.

Abstract: The memory storage, transmission and processing demands of a vectored DSL system are reduced by sampling a subset of DSL tones in the DSL tone range used in the vectored system. This data is smoothed (denoised) to further reduce the data's size, sacrificing some fidelity or precision as a result. Finally, lossless entropy coding or the like is performed to encode the FEXT cancellation data for storage and use. The resulting data is less likely to cause transmission bottlenecks in the vectored system, can be stored and used more efficiently for both on-chip and off-chip vectoring implementations, and can be readily updated in various ways.

Abstract: An improved training sequence for acquiring symbol boundary timing at a receiver of a data transmission system is disclosed. One aspect pertains to an improved training sequence wherein groups of identical symbols are transmitted by a transmitter. These symbols can be supplied to the transmitter in a time domain or a frequency domain manner. The improved training sequence facilitates symbol boundary determination at a receiver.