Multiplex communications – Pathfinding or routing – Switching a message which includes an address header
Reexamination Certificate
2008-05-20
2010-11-16
Pham, Chi H (Department: 2471)
Multiplex communications
Pathfinding or routing
Switching a message which includes an address header
Reexamination Certificate
active
07835368
ABSTRACT:
A method is described for reducing self-induced far end crosstalk (self-FEXT) in a multiple input multiple output (MIMO) digital subscriber line (xDSL) system. An initial value for an off-diagonal multiple input multiple output canceller (ODMC) is derived while the ODMC is inactive and while in data mode. The method includes activating the initial ODMC and converging towards an steady-state value for the ODMC by performing an adaptive algorithm to maximize the Shannon's capacity of the system and to reduce upstream self-FEXT. Bit loading is performed and a frequency domain equalizer (FEQ) is updated.
REFERENCES:
patent: 6292559 (2001-09-01), Gaikwad
patent: 6999583 (2006-02-01), Valenti et al.
patent: 7023908 (2006-04-01), Nordstrom et al.
patent: 7577209 (2009-08-01), Poon
patent: 2001/0004383 (2001-06-01), Nordstrom
patent: 2006/0002462 (2006-01-01), Park
patent: 2006/0056522 (2006-03-01), Tsatsanis
patent: 2006/0227815 (2006-10-01), Khan
patent: 2007/0004286 (2007-01-01), Hobbel
patent: 2007/0110135 (2007-05-01), Guess et al.
Duvaut, R, et al., Adaptive Off-Diagonal MIMO Pre-Coder (ODMP) for Downstream DSL Self FEXT Cancellation, proceedings of GlobeCom, Nov. 25-28, 2007, Washington-DC, USA.
Bliss, D.W.,et al.,“Environmental issues for MIMO Capacity”, IEEE transaction on Signal processing, vol-50, Issue 9, pp. 2128-2142, Sep. 2002.
G.993.2, Very High Speed Digital Subscriber Line Transceiver 2, VDSL2, Feb. 2006, ITU-T.
Wiese, B.R. & Chow, J.S., “Programmable Implementation of xDSL transceivers”, IEEE Communication Magazine, vol. 38, Issue 5, May 2000.
Cendrillon, R. et al., “Partial Crosstalk Cancellation for Upstream VDSL”, Eurasip Journal on Applied Signal Processing, 2004:10, pp. 1520-1535.
G. Ginis and J.M. Cioffi, “Vectored Transmission for Digital Subscriber Line Systems,” IEEE J. Select. Areas Commun., vol. 20, No. 5, pp. 1085-1124, Jun. 2002.
R. Cendrillon et al., “Improved Linear Crosstalk Precompensation for DSL,” in Proc. IEEE ICASSP, May 2004, pp. 1053-1056.
Actelis Networks, “Channel Estimation by ‘Abuse’ of Receivers,” NIPPNAI-098, Savannah, Georgia, 2006.
J. Louveaux and A.J. Van Der Veen, “Error Sign Feedback as an Alternative to Pilots for Tracking of FEXT Transfer Functions in Downstream VDSL,” EURASIP J. Applied Signal Processing, vol. 2006, pp. 1-14.
J. Louveaux and A.J. Van Der Veen, “Adaptive DSL Crosstalk Precancellation Design Using Low-Rate Feedback From End Users,” IEEE Signal Proc. Letters, vol. 13, No. 11, pp. 665-668, Nov. 2006.
Conexant Systems, “G.vdsl: Proposed Requirements on Back Channel for Estimating MIMO Channel in VDSL2”, CD-041, Denver, Colorado, Sep. 25-29, 2006.
E. Karipidis et al., “Crosstalk Models for Short VDSL2 Lines from 30MHz Measured Data”, Eurasip Journal on Applied Signal processing, vol. 2006, Article 85859, pp. 1-9.
Conexant Systems, “Updated Proposal for Construction of a MIMO Channel Model for Evaluation of FEXT Cancellation Systems,” NIPPNAI-2007-009R1, San Francisco, California, 2007.
Conexant Systems, “G.vdsl: Using Error Samples for Downstream Self FEXT Cancellation Pre-coding in VDSL2,” SD-052, San Diego, California, 2007.
A. Leshem and L. Youming, “A Low Complexity Coordinated FEXT Cancellation for VDSL” ICECS, Dec. 2004, pp. 338-341.
Upzide labs, “G.vdsl: Using orthogonal pilot sequences for assisting FEXT channel estimation in vector transmission.”, ITU SD-036, San Diego, California Jan. 15-19, 2007.
Benveniste, Albert, “Adaptive Algorithms for Stochastic Approximations,” Springer Verlag, New-York, 1990.
International Search Report and Written Opinion.
Biyani Pravesh
Duvaut Patrick
Mahadevan Amitkumar
Maheshwari Satyavardhan
Singh Shailendra
Ikanos Communications Inc.
Ng Fan
Pham Chi H
Thomas Kayden Horstemeyer & Risley LLP
LandOfFree
Systems and methods for mitigating the effects of upstream... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Systems and methods for mitigating the effects of upstream..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Systems and methods for mitigating the effects of upstream... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-4208557