Abstract: In general, the present invention provides an efficient usage of Far End Crosstalk (FEXT) coefficient memory in a G.fast vectoring system. According to certain aspects, embodiments of the invention provide a simple scheme for efficient management of the Discontinuous (DO) and Regular Operation (RO) FEXT coefficient memories to handle the complexity of lines joining/leaving the system in both regular and DO groups. In embodiments, by disabling the power-efficient, Discontinuous Operation, a G.fast system according to the invention first frees up the DO coefficient memory. Next, the system uses this memory as the staging area to manage joining/leaving events. Finally the system re-enables to the power-efficient Discontinuous Operation and re-populates the DO coefficient memory.

Abstract: According to certain aspects, the present invention improves upon the conventional TCAM scheme by allowing a traditional TCM scheme to be used while in RCM mode. In a RCM mode according to embodiments of the invention, the system uses traditional TCM+SNR margin (i.e. SNRM) with a receiver controlled bit allocation table (BAT) and tone ordering table (TOT). In a TCAM mode according to embodiments of the invention, the system uses uncoded hierarchical modulation similar to the modulation originally proposed for TCAM. According to certain aspects, the transmitter in RCM mode in embodiments of the invention can determine when line conditions require a switch to TCAM mode, and signal the transition to the receiver. Likewise, when in a TCAM mode according to embodiments of the invention, the receiver can request to switch back to RCM via a SRA mechanism, for example.

Abstract: The present invention is directed to methods and apparatuses for performing concurrent vectoring of systems having communications performed at different symbol rates. In embodiments, where a common binder includes different sub-groups of lines having corresponding different symbol rates, the invention includes methods and apparatuses for managing and concurrently vectoring all the lines of the different sub-groups.

Abstract: Embodiments of the invention provide a robust mechanism to isolate transceivers that attempt to train on a FEXT channel during the handshake phase and to abort a false activation. According to aspects of the invention, either or both transceiver acknowledges the unique identity of the other transceiver during the handshake phase. This ensures that the transceiver progresses to training and beyond with only one other remote transceiver.

Abstract: In general, the present invention is related to methods and apparatuses for performing an efficient update of Far-End Cross Talk (FEXT) coefficients for use with Discontinuous Operation (DO) in G.fast systems. In embodiments, to maintain separate FEXT coefficient matrices for both the Regular Operation (RO) group and the smaller DO group, the updates to the DO coefficient matrix are performed independently from the updates to the RO coefficient matrix. In these and other embodiments, the updates are performed using LMS updates and known data symbols, and with the same frequency as the LMS updates to the RO coefficient matrix.

Abstract: In general, the present invention provides an efficient usage of Far End Crosstalk (FEXT) coefficient memory in a G.fast vectoring system. According to certain aspects, embodiments of the invention provide a simple scheme for efficient management of the Discontinuous (DO) and Regular Operation (RO) FEXT coefficient memories to handle the complexity of lines joining/leaving the system in both regular and DO groups. In embodiments, by disabling the power-efficient, Discontinuous Operation, a G.fast system according to the invention first frees up the DO coefficient memory. Next, the system uses this memory as the staging area to manage joining/leaving events. Finally the system re-enables to the power-efficient Discontinuous Operation and re-populates the DO coefficient memory.

Abstract: According to certain aspects, the present invention improves upon the conventional TCAM scheme by allowing a traditional TCM scheme to be used while in RCM mode. In a RCM mode according to embodiments of the invention, the system uses traditional TCM+SNR margin (i.e. SNRM) with a receiver controlled bit allocation table (BAT) and tone ordering table (TOT). In a TCAM mode according to embodiments of the invention, the system uses uncoded hierarchical modulation similar to the modulation originally proposed for TCAM. According to certain aspects, the transmitter in RCM mode in embodiments of the invention can determine when line conditions require a switch to TCAM mode, and signal the transition to the receiver. Likewise, when in a TCAM mode according to embodiments of the invention, the receiver can request to switch back to RCM via a SRA mechanism, for example.

Abstract: The present invention is directed to methods and apparatuses for performing concurrent vectoring of systems having communications performed at different symbol rates. In embodiments, where a common binder includes different sub-groups of lines having corresponding different symbol rates, the invention includes methods and apparatuses for managing and concurrently vectoring all the lines of the different sub-groups.

Abstract: The present invention relates to methods and apparatuses for extending the benefits of vectoring technology to xDSL systems including disparate types of xDSL lines. In embodiments, the invention includes a scheme to match the symbol frequencies of ADSL2 and VDSL2 lines, to then enable vectoring of ADSL2 FEXT into VDSL2 lines.

Abstract: Embodiments of the invention provide a robust mechanism to isolate transceivers that attempt to train on a FEXT channel during the handshake phase and to abort a false activation. According to aspects of the invention, either or both transceiver acknowledges the unique identity of the other transceiver during the handshake phase. This ensures that the transceiver progresses to training and beyond with only one other remote transceiver.