| 1. |
- Acatauassu, Diogo, et al.
(författare)
-
Simple and Causal Copper Cable Model Suitable for G.fast Frequencies
- 2014
-
Ingår i: IEEE Transactions on Communications. - 0090-6778. ; 62:11, s. 4040-4051
-
Tidskriftsartikel (refereegranskat)abstract
- G.fast is a new standard from the International Telecommunication Union, which targets 1 Gb/s over short copper loops using frequencies up to 212 MHz. This new technology requires accurate parametric cable models for simulation, design, and performance evaluation tests. Some existing copper cable models were designed for the very high speed digital subscriber line spectra, i.e., frequencies up to 30 MHz, and adopt assumptions that are violated when the frequency range is extended to G.fast frequencies. This paper introduces a simple and causal cable model that is able to accurately characterize copper loops composed by single or multiple segments, in both frequency and time domains. Results using G.fast topologies show that, apart from being accurate, the new model is attractive due to its low computational cost and closed-form expressions for fitting its parameters to measurement data.
|
|
| 2. |
- Andersson, Jens A, et al.
(författare)
-
Analytic Model for Cross-Layer Dependencies in VDSL2 access networks
- 2014
-
Ingår i: 22nd International Conference on Software, Telecommunications and Computer Networks (SoftCOM), 2014. - 9781479964970 - 9789532900521 ; , s. 269-273
-
Konferensbidrag (refereegranskat)abstract
- Recent changes in user employment of Internet based services, new deployment technologies for mobile networks as well as an ongoing realisation of fixed and mobile converged networks e.g. the EU FP7 project COMBO, are significant examples of enablers for increasing demands on DSL links. Investigating cross-layer dependencies between all layers in the OSI reference model becomes increasingly important. In this paper we present an analytical model and experimental results for the relation between impulse noise on a VDSL2 link and the effect this have on the network layer packet loss. We show how the packet loss rate is dependent not only on the disturbance signal level and periodicity but also on the link utilisation.
|
|
| 3. |
- Gosselin, Stéphane, et al.
(författare)
-
Fixed and Mobile Convergence: Needs and Solutions
- 2014
-
Konferensbidrag (refereegranskat)abstract
- The drivers of Fixed and Mobile Convergence (FMC) are discussed. A reference framework for FMC proposed by European project COMBO is then presented. Some use cases of FMC are described, showing the needs for mutualization and convergence of fixed and mobile broadband networks. Five network scenarios providing technical solutions to FMC use cases are proposed. They target an optimal and seamless quality of experience for the end user together with an optimized network infrastructure ensuring increased performance, flexibility, reduced cost and reduced energy consumption.
|
|
| 4. |
- Müller, Francisco, et al.
(författare)
-
Optimizing Power Normalization for G.fast Linear Precoder by Linear Programming
- 2014
-
Ingår i: 2014 IEEE International Conference on Communications, ICC 2014. - 9781479920037 ; , s. 4060-4065
-
Konferensbidrag (refereegranskat)abstract
- The use of vectoring for crosstalk cancellation in the new ITU-T G.fast standard for next generation DSL systems becomes essential for efficient utilization of the extended bandwidth (up to 200 MHz). In VDSL2 (up to 30 MHz), a zero-forcing-based linear precoder is used in downstream which approaches single-line performance. However, at high frequencies, the linear precoder may amplify the signal power substantially since the crosstalk channel is much stronger than at lower frequencies. Performance could be significantly degraded by power normalization to keep the PSD below the mask. In this work, we extended a per-line power normalization scheme by linear programming (LP) optimization. By simulations using measured cable data it is shown how the LPbased scheme further improves the linear precoder and it is also capable of balancing the data rate between lines. Further, the simulations also show the non-linear Tomlinson-Harashima precoder performs better than the linear precoders.
|
|
