Defining upstream power backoff for VDSL

Schelstraete, S.

doi:10.1109/jsac.2002.1007387

Cited by 21 publications

(8 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This unequal-length FEXT scenario would necessitate a power backoff scheme in order to ensure reasonably low crosstalk levels on our loop [40,41]. However, in case power backoff is employed, the nearby modem has to reduce its transmit power, thus limiting its own data rate.…”

Section: Example 1: Vdsl Upstream Transmission With Strong (Close) Sementioning

confidence: 99%

Information rate bounds in common‐mode aided wireline communications

Magesacher

Ödling

Börjesson

et al. 2005

Trans Emerging Tel Tech

View full text Add to dashboard Cite

SUMMARYCommunication over the copper twisted-pair channel is performed by transmitting and receiving differential-mode (DM) signals. In this paper, we extend the conventional DM receiver scheme by incorporating the common-mode (CM) signal, which is strongly correlated with the DM signal and can be extracted at the end of every wire pair. The wireline channel, including the CM receive signal, is modelled as a Gaussian vector (multiple-input multiple-output) channel with memory and an arbitrary number of disturbers that introduce interference which can be correlated both temporally and spatially. We investigate the potential of CM-aided reception in terms of information rate for single-user digital subscriber line systems (xDSL) operating on a single pair. Numerical results of information rate calculations using measured channel data are presented. The achievable information rate of the twisted-pair channel when incorporating the CM signal in practically relevant example scenarios can exceed the information rate of the conventional DM channel by a factor of up to two.

show abstract

Section: Example 1: Vdsl Upstream Transmission With Strong (Close) Sementioning

confidence: 99%

Information rate bounds in common‐mode aided wireline communications

Magesacher

Ödling

Börjesson

et al. 2005

Trans Emerging Tel Tech

View full text Add to dashboard Cite

show abstract

“…Further aspects of wireline transmission are upstream power back-off [19][20][21] to take care of the near-far problem, furthermore dynamic spectral management to allocate the available resources in a more dynamic way (e.g., iterative water filling [22,23], NRIA [24], a game-theoretic approach [25]], and finally, MIMO approaches in the form of two-sided and one-sided processing. We shortly introduce these approaches which make use of the FEXT functions additionally to the transfer function.…”

Section: Discrete Multitone (Dmt)mentioning

confidence: 99%

OFDM/DMT for Wireline Communications

Henkel

Mayrock

Haunstein

et al. 2011

Signals and Communication Technology

View full text Add to dashboard Cite

With wireline, we mean digital subscriber lines as well as optical transmission. Apart from the general aspects of multicarrier modulation, the channel properties are very different. It is thus unavoidable to go into some details of channel transfer characteristics and disturbances. In DSL, the channel characteristics are determined by the propagation constant, the characteristic impedance, and the loop structure, furthermore crosstalk from other loops and ingress (RFI, impulse noise) from outside. In copper loops, the frequency dependent transfer function of the twisted pairs together with possible reflections at splices lead to dispersion which we will also see in optical transmission. There, we distinguish chromatic dispersion and polarization mode dispersion. Optical transmission especially also suffers from non-linear characteristics (Kerr effect), which does not have a counterpart in copper cables. In copper transmission, non-linearities are especially due to the limitations of the D/A converters and power amplifiers, which may lead to clipping of the almost Gaussian distributed time-domain signal of OFDM. This holds for all OFDM transmission. Other nonlinearities may be due to baluns (transformers) used in DSL, but practically, they are of minor relevance.In the following two sections, we will study properties of the channel and specialties of the multicarrier transmission over twisted pairs and optical fibers. Thereafter, we consider a new approach for impulse noise cancellation in DSL and the simulation of optical multicarrier transmission. Discrete MultiTone (DMT) and WirelineChannel Properties W. Henkel, Jacobs University Bremen, GermanyThis chapter describes basic properties of the wireline twister-pair channel and introduces DMT (Discrete MultiTone), the baseband variant of OFDM. Further information can, e.g., be found in a student book project [1], or [2-5]. Properties of the Twisted-Pair ChannelThe twisted pair (TP) cable channel is characterized by a transfer function that is increasingly attenuating with frequency and cross-talk functions that increase with frequency, as well. Furthermore, ingress from radio interferers (RFI), e.g., amateur radio, and impulse noise have a strong impact. In the following, we describe the

show abstract

“…This well-known effect, which resembles the "near-far" problem in wireless communications, can be mitigated through the application of Upstream Power Back-Off (UPBO) [2], [3].…”

Section: Introductionmentioning

confidence: 99%

Dynamic upstream power back-off for mixtures of vectored and non-vectored VDSL

Chen¹,

Ginis²,

Mohseni³

2014

2014 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)

View full text Add to dashboard Cite

Far-end crosstalk severely degrades upstream rates in mixtures of vectored and non-vectored Very high-speed Digital Subscriber Loops (VDSL). As replacement of non-vectored VDSL systems by vectored VDSL systems is expected to be gradual, a crucial problem is the upstream rate optimization of vectored lines while maintaining the rate targets of nonvectored lines. To address this problem, this paper describes an algorithm that selects suitable Upstream Power Back-Off parameters for the vectored and the non-vectored lines. The algorithm has much lower computation requirements compared to Optimal Spectrum Balancing (OSB), yet simulation results show that the achievable vectored rates are very close to the OSB theoretical limits.Index Terms-Digital subscriber line, dynamic spectrum management, upstream power back-off, vectored VDSL

show abstract

Defining upstream power backoff for VDSL

Cited by 21 publications

References 8 publications

Information rate bounds in common‐mode aided wireline communications

Information rate bounds in common‐mode aided wireline communications

OFDM/DMT for Wireline Communications

Dynamic upstream power back-off for mixtures of vectored and non-vectored VDSL

Contact Info

Product

Resources

About