Analytical evaluation of the role of estimation and quantization errors in downstream vectored VDSL systems

We investigate the effect of non idealities in the diagonalizing precoder vectoring technique used for cancellation of the far-end crosstalk in downstream VDSL networks. By using analytical formulas, we estimate the average bit rate achievable as a function of both relative and absolute estimation errors. Several numerical examples are provided, in different scenarios and operation conditions. Results are presented covering an important aspect for practical applications: the transmitted power required to achieve a target bit rate, as a function of the line length. Finally, we provide some results on the impact of a smart quantization law, which limits the performance loss.

[1]  Alle-Jan van der Veen,et al.  Adaptive Precoding for Downstream Crosstalk Precancelation in DSL Systems Using Sign-Error Feedback , 2010, IEEE Transactions on Signal Processing.

[2]  P. Cardieri,et al.  Statistics of the sum of lognormal variables in wireless communications , 2000, VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026).

[3]  S. Schwartz,et al.  On the distribution function and moments of power sums with log-normal components , 1982, The Bell System Technical Journal.

[4]  Youming Li,et al.  A Low Complexity Linear Precoding Technique for Next Generation VDSL Downstream Transmission Over Copper , 2007, IEEE Transactions on Signal Processing.

[5]  P. Duvaut,et al.  Construction of a DSL-MIMO channel model for evaluation of FEXT cancellation systems in VDSL2 , 2007, 2007 IEEE Sarnoff Symposium.

[6]  Nikos D. Sidiropoulos,et al.  Finite Word Length Effects on Transmission Rate in Zero Forcing Linear Precoding for Multichannel DSL , 2009, IEEE Transactions on Signal Processing.

[7]  Joseph Musson,et al.  TITLE Maximum Likelihood Estimation of the Primary Parameters of Twisted Pair Cables , 1998 .

[8]  John M. Cioffi,et al.  Vectored transmission for digital subscriber line systems , 2002, IEEE J. Sel. Areas Commun..

[9]  Roberto Garello,et al.  On the Effect of Estimation and Quantization Errors in Downstream VDSL Systems , 2010, 2010 Third International Conference on Communication Theory, Reliability, and Quality of Service.

[10]  Roberto Garello,et al.  Simple Statistical Analysis of the Impact of Some Nonidealities in Downstream VDSL with Linear Precoding , 2010, EURASIP J. Adv. Signal Process..

[11]  Ronen Yizhaq Gilad,et al.  Vectored VDSL from a practical perspective: ISmart FEXT cancellation performance , 2010, 2010 IEEE Sensor Array and Multichannel Signal Processing Workshop.

[12]  P. Turcza,et al.  RLS based MIMO channel identification for FEXT compensation in vectored xDSL system , 2005, Proceedings of the 2005 European Conference on Circuit Theory and Design, 2005..

[13]  Wei Yu.  Multiuser Water-filling in the Presence of Crosstalk , 2007, 2007 Information Theory and Applications Workshop.

[14]  Marc Moonen,et al.  A Near-Optimal Linear Crosstalk Precoder for Downstream VDSL , 2007, IEEE Transactions on Communications.

[15]  John M. Cioffi,et al.  The ITU-T's new g.vector standard proliferates 100 mb/s dsl , 2010, IEEE Communications Magazine.

[16]  Issam Wahibi,et al.  Channel Estimation Using Data and Pilots for a Coordinated DSL System , 2007, IEEE GLOBECOM 2007 - IEEE Global Telecommunications Conference.