TY - GEN
T1 - Optimal transmit spectra for communication in the presence of crosstalk and imperfect echo cancellation
AU - Ahmed, N.
AU - Baraniuk, R. G.
AU - Shaver, D. P.
N1 - Funding Information:
This work was supported by the National Science Foundation, Texas ATP, and Texas Instruments Leadership University program. Email: {nahmed. richb}@rice.edu. shaver@ti.com. Web: http://www.dsp.rice.edu
Publisher Copyright:
© 2001 IEEE.
Copyright:
Copyright 2016 Elsevier B.V., All rights reserved.
PY - 2001
Y1 - 2001
N2 - In many communication systems, including Digital Subscriber Lines, performance is severely limited by crosstalk interference. Previous work has presented a general framework for designing optimal transmit spectra for crosstalk avoidance. The technique uses the channel, noise, and interference characteristics to setup and solve an optimization problem which maximizes the capacity of neighboring lines, while maintaining spectral compatibility with other services. This joint signaling and optimal power distribution technique yields significant performance gains over conventional fixed spectra in terms of bit-rates and performance margins. In general, the spectra that result from this scheme have both an echo cancelled and frequency division multiplexed region. To ease the analysis, this technique assumed that the echo canceller has perfect echo rejection capability, which in practice is not true. In this paper, we propose an extension to these techniques, in which we factor the performance of practical echo cancellers into the optimization procedure. When echo rejection is not perfect, as is generally the case, our technique shows significant performance gains over previous techniques. As the performance of the echo canceller increases, our technique converges to the same solution.
AB - In many communication systems, including Digital Subscriber Lines, performance is severely limited by crosstalk interference. Previous work has presented a general framework for designing optimal transmit spectra for crosstalk avoidance. The technique uses the channel, noise, and interference characteristics to setup and solve an optimization problem which maximizes the capacity of neighboring lines, while maintaining spectral compatibility with other services. This joint signaling and optimal power distribution technique yields significant performance gains over conventional fixed spectra in terms of bit-rates and performance margins. In general, the spectra that result from this scheme have both an echo cancelled and frequency division multiplexed region. To ease the analysis, this technique assumed that the echo canceller has perfect echo rejection capability, which in practice is not true. In this paper, we propose an extension to these techniques, in which we factor the performance of practical echo cancellers into the optimization procedure. When echo rejection is not perfect, as is generally the case, our technique shows significant performance gains over previous techniques. As the performance of the echo canceller increases, our technique converges to the same solution.
KW - Digital Subscriber Line (DSL)
KW - capacity
KW - crosstalk
KW - echo canceller
KW - power distribution
KW - transmit spectra
KW - waterfilling
UR - http://www.scopus.com/inward/record.url?scp=84963820811&partnerID=8YFLogxK
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U2 - 10.1109/ETS.2001.979412
DO - 10.1109/ETS.2001.979412
M3 - Conference contribution
AN - SCOPUS:84963820811
T3 - 2001 IEEE Emerging Technologies Symposium on BroadBand Communications for the Internet Era, ETS 2001 - Symposium Digest
SP - 17
EP - 21
BT - 2001 IEEE Emerging Technologies Symposium on BroadBand Communications for the Internet Era, ETS 2001 - Symposium Digest
A2 - Winson, Peter
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - IEEE Emerging Technologies Symposium on BroadBand Communications for the Internet Era, ETS 2001
Y2 - 10 September 2001 through 11 September 2001
ER -